Abstract:
A Mat ( 1 ) in the form of a liner or pad for sanitary installations is formed of a carrier ( 3 ) of flexible plastic with suction cups ( 5 ) located on its bottom ( 4 ) and a layer of nonwoven fabric ( 2 ) on its top ( 1.1 ) is constructed to enable the mat ( 1 ) to be efficiently produced and for the mat to have good adhesion between the nonwoven fabric ( 2 ) and the carrier ( 3 ) even when experiencing high squeezing stress. This is achieved by making the carrier ( 3 ) of a thermoplastic elastomer (TPE) injecting the elastomer onto the back of nonwoven fabric ( 2 ) in an injection mold.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a mat in the form of a liner or pad for sanitary facilities, such as bathtubs, shower stalls, washstands, or the like. In particular, the invention relates to such mats as are made of a carrier of flexible plastic with suction cups on its bottom and a layer of nonwoven fabric on its top. Additionally, the invention also relates to an injection mold comprised of at least two mold parts which can be moved towards and away from one another for producing such a mat. 
     2. Description of Related Art 
     A mat of the type to which the present invention is directed is known from German Patent Application DE 3028661 A1. This mat has a lattice-like carrier to which suction cups are attached on one side. On the side of the carrier opposite the suction cups, a layer of textile material, for example, a nonwoven fabric, is attached. As a result of the lattice-like nature of the carrier, there are openings which are covered by nonwoven fabric, but which enable easy, rapid sinking, for example, in a filled bath, as a result of the permeability of the nonwoven fabric. The openings are therefore covered by a layer to make the mat kind to the skin. 
     A mat with a network-like carrier is also known from German Patent Application DE 241294 A2. The network-like carrier of this mat is jacketed with a foamed plastic such that the openings remain open. This is intended to avoid subsequent production of openings and thus enable efficient manufacture. 
     Finally, German Utility Model DE-GM 7721240 discloses a mat with a rubbing or cleaning coating on its carrier in the form of flexible pegs or bristles. Thus, for example, cleaning or massaging of the back when showering or bathing will be enabled, the mat being attached by means of molded suction cups to the bathtub or the wall of the shower stall. 
     SUMMARY OF THE INVENTION 
     A primary object of this invention is to be able to efficiently produce a mat of the initially mentioned type. 
     In conjunction with foregoing object, it is a further object of the invention to, at the same time, obtain good adhesion between the nonwoven fabric and carrier to an extent which will be permanently ensured even under high squeezing stress. 
     These objects are achieved in accordance with embodiments of the invention by forming the carrier of a thermoplastic elastomer (TPE) which has been back-injected onto a nonwoven fabric. 
     With the invention, the nonwoven fabric has such a high wear resistance that the carrier will tear before the nonwoven fabric will come loose from the carrier. This is due to the fact that the nonwoven fabric is covered over a very large surface by thermoplastic elastomer material. The elastic penetrates deep into the nonwoven fabric, but not through it, so that the anti-slip property of the nonwoven fabric is essentially preserved. Nor does the nonwoven fabric lose the ability to prevent formation of water puddles on its surface. 
     These and further objects, features and advantages of the present invention will become apparent from the following description when taken in connection with the accompanying drawings which, for purposes of illustration only, show several embodiments in accordance with the present invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1 and 2 each show a perspective view of section through a piece of a mat in accordance with the present invention; 
     FIGS. 3 through 8 each show a cross section through a mat segment of a respective different embodiment of the mat in accordance with the present invention; 
     FIG. 9 is a schematic representation of one advantageous two-part injection mold for producing the mat of the invention; 
     FIG. 10 shows a mold with a special design of the shaping surface for the nonwoven fabric for forming elevations and/or depressions; and 
     FIG. 11 shows a mold with retaining elements for the nonwoven fabric to be inserted. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 shows a section of a mat  1  which is formed of a nonwoven fabric  2  which having an exposed surface  1 . 1  to which a carrier  3  of thermoplastic elastomer (TIE) has been back-injected. Suction cups  5  are molded onto the bottom  4  of the carrier  3 , so that they form a homogenous structural unit with the carrier  3 . 
     Nonwoven fabric  2  can be made colorless, monocolored or multicolored. Nonwoven fabric  2  can also be imprinted with one or more decorations  6 , one or more patterns, one or more graphics, or the like. 
     In the embodiment shown in FIG. 2, the nonwoven fabric  2  is plastically deformed so that elevations  7  and depressions  8  result at the top and bottom sides thereof. This is done during application of the carrier  3  to the fabric  2  as described more fully below. 
     According to one advantageous embodiment of the invention, shown in FIG. 3, the nonwoven fabric  2  has at least one opening  9  that is filled with the material of carrier  3 . In this way, the surface  10  of mat  1 , preferably, acquires better anti-slip properties than when using nonwoven fabric  2  alone. In this embodiment, the nonwoven fabric  2  terminates at the outside edge  11  of the mat  1 , so that face  2 . 1  of edge  2 . 2  of nonwoven fabric  2  is exposed and is aligned with the outside edge  11 . 
     However, the nonwoven fabric  2  can also be smaller than the mat dimensions, so that the outside edge  11  of mat  1  is only partially covered by the nonwoven fabric  2 . The outside edge  11  can also be made staggered or stepped to the inside and outside, as shown in FIG.  4 . 
     In one advantageous aspect of the invention, a nonwoven fabric  2  can be used which, as is conventional, is provided on its underside with a heat-sealable layer  12 , as is illustrated in FIG.  5 . The material of heat-sealable layer  12 , preferably, has a melting point which is in the range of the melting point of the carrier material and which is preferably lower than it. 
     Advantageously, a nonwoven fabric  2  is used which is comprised of a hot-bonded or hot-bondable material and/or which contains this material, for example, in the form of a coating or impregnation. Thus, on the one hand, the stability of the surface shape of the nonwoven fabric  2  is guaranteed, and on the other hand, dimensionally-stable production of elevations  7  and/or depressions  8  during the injection molding process in the manufacture of carrier  3  is enabled. 
     Another development of the invention calls for providing the nonwoven fabric  2  with a cutout  13  into which at least one pattern  14  is inserted as represented in FIG.  6 . The shape of cutout  13  and/or inserted pattern(s)  14  can have different geometries or figures. Pattern(s)  14  can completely or only partially fill cutout  13  and thus may or may not touch nonwoven fabric  2 . 
     Pattern(s)  14  can be made of any material; but, preferably, a nonwoven fabric is likewise used. This nonwoven fabric can have the same or different properties as nonwoven fabric  2 . Thus, the inserted nonwoven fabric can have a different color, different decoration and/or different graphics and/or different thickness and/or different density or the like relative to the nonwoven fabric  2 . 
     According to the embodiments shown in FIGS. 7 &amp; 8, the pattern  14  can be made or located elevated and/or depressed (represented by broken lines). In this case, the face  14 . 1  of edge  14 . 2  of pattern  14  need not be surrounded by the material of carrier  3 , as FIG. 7 shows. On the other hand, the face  14 . 1  can also be covered by this material (FIG. 8) or the material can project over edge  14 . 1 . 
     The thickness of nonwoven fabric  2  and/or pattern  14  is roughly 0.1 mm to 1 mm, especially 0.2 mm to 0.6 mm. 
     FIG. 9 shows a two-part injection mold  15  for producing mat  1 . In first mold part  15 . 1 , there is depression  15 . 11  of the size of nonwoven fabric  2  to be inserted into the mold part  15 . 1 . 
     In the second mold part  15 . 2 , there are peripherally undercut depressions  15 . 21 ,  15 . 22  in which suction cups  5  are formed in the injection molding process. 
     Mold part  15 . 1  has, preferably, within depression  15 . 11 , other depressions  15 . 12  and/or projections  15 . 13  which form the shape of elevations  7  or depression  8  of nonwoven fabric  2  as shown in FIG.  10 . 
     So that nonwoven fabric  2  maintains its position when inserted into mold part  15 . 1 , especially in a vertical arrangement of injection mold  15 , as shown, the inner surface  15 . 4  of the mold part has, at least on upper edge  15 . 16 , retaining elements  16 . For example, the retaining elements  16  can ben knin the form of pins and/or hooks and/or teeth or the like. Retaining elements  16  can also be distributed over a major portion of surface  15 . 14  or over the entire surface  15 . 14 . Retaining elements  16 , when the nonwoven fabric  2  is inserted in to the mold, fit into or penetrate it, and thus, fix the fabric  2  in the position necessary for the injection molding process. The length or projecting height of retaining elements  16  can be chosen to be larger than the thickness of the nonwoven fabric  2  so that they can penetrate through it. The ends projecting on the other side are then molded into the material of carrier  3 . 
     In addition to or instead of retaining elements  16  and/or the depression  15 . 11 , the mold can be provided with suction openings  17 , for example, in the form of holes or passages, in at least one of mold part  15 . 1  and/or  15 . 2 , which are connected to a suction device  18 , for example, a vacuum pump, so that the negative pressure holds or assists in holding the nonwoven fabric  2  in position when a vacuum or negative pressure is applied by suction device  18 . 
     While various embodiments in accordance with the present invention have been shown and described, it is understood that the invention is not limted thereto, and is susceptible to numerous changes and modifications as known to those skilled in the art. Therefore, this invention is not limited to the details shown and described herein, and includes all such changes and modifications as are encompassed by the scope of the appended claims.