Abstract:
A polyethylene tape including a first backing layer, a second backing layer, a third backing layer, and an adhesive layer in sequence. The first and the third backing layers are transparent polyethylene films which sandwich the second backing layer therebetween. The second backing layer is a colored polyethylene film. The adhesive layer is acrylic glue coated on the third backing layer. The first and the third backing layers isolate the second backing layer from the adhesive layer even if the polyethylene tape is reeled up into a roll.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention relates generally to a tape to be attached to an object for protection or fixing, and more particularly to a structure of a polyethylene tape. 
         [0003]    2. Description of Related Art 
         [0004]    As the improvement of industrial technology, adhesive tapes are widely used in ordinary and engineering fields. Typically, the conventional tapes are made of polyvinylchloride (PVC), which is cheaper and easy to be manufactured. 
         [0005]    The conventional PVC tape is reeled up into a roll for sale. For a roll of the PVC tape, the adhesive side of the tape is stuck on the back side of the tape, and the leaves some adhesive on the back side of the tape after a user pulled the tape out of the roll. This residual adhesive on the back side of the tape gives some bad effect on the use of the PVC tape, such as transfer to user&#39;s hand. 
         [0006]    Another problem of the conventional PVC tape is that plasticizer will come out from the backing material when the PVC tape is put in a high-temperature environment or in a large temperature-difference environment. It results some problems, such as sticky on the cross-sectional surface, adhesive flow, shifting of the tape in the roll, and poor anti-aging capacity. In other words, the conventional PVC tape has several drawbacks, such as not good for the user to operate it, clearing problem, and poor durability. 
         [0007]    In recent days, the development of environmentally friendly materials, so called eco-materials, is proceeding in many countries. In  2004 , European Union rejected any electrical device or industrial product containing lead and halogen. Therefore, it needs an alternated material to replace the PVC tape, which contains chloride. 
         [0008]    Some manufactures of the tapes starts to develop the backing material of the tape of single-layered polyethylene (PE) to fix the problems of above. 
         [0009]    However, when the PE tape is printed with texts or icons or colored, the ink will have an affinity with the adhesive on the tape. As a result, the ink will transfer to the adhesive and make the adhesive be colored or printed with texts or icons. 
         [0010]    In conclusion, the conventional PE tape still needs to be improved. 
       BRIEF SUMMARY OF THE INVENTION 
       [0011]    The primary objective of the present disclosure directs to a polyethylene tape, which has no drawback as described above. 
         [0012]    In order to achieve the objective of the present invention, the polyethylene tape of the present invention includes a first backing layer, which is made of polyethylene, and is transparent; a second backing layer, which is made of polyethylene, and is colored, wherein the second backing layer is attached to the first backing layer; a third backing layer, which is made of polyethylene, and is transparent, wherein the third backing layer is attached to the second backing layer, so that the second backing layer is between the first backing layer and the third backing layer; and an adhesive layer, which is acrylic glue, attached to the third backing layer, wherein the third backing layer is between the adhesive layer and the second backing layer. 
         [0013]    In an embodiment, the polyethylene tape further includes an ink layer on the first backing layer, wherein the first backing layer is between the ink layer and the second backing layer, and a color of the ink layer is different from that of the second backing layer. 
         [0014]    In an embodiment, the polyethylene tape further includes an antistatic layer and a release layer, wherein the antistatic layer is made of a conductive material, and is attached to the ink layer, so that the ink layer is between the first backing layer and the antistatic layer; the release layer contains a release agent, and is attached to the antistatic layer, so that the antistatic layer is between the release layer and the ink layer. 
         [0015]    In an embodiment, the polyethylene tape further includes a release layer, wherein the release layer contains a release agent, and is attached to the ink layer, so that the ink layer is between the release layer and the first backing layer. 
         [0016]    In an embodiment, the polyethylene tape further includes an antistatic layer and a release layer, wherein the antistatic layer is made of a conductive material, and is attached to the first backing layer, so that the first backing layer is between the second backing layer and the antistatic layer; the release layer contains a release agent, and is attached to the antistatic layer, so that the antistatic layer is between the release layer and the first backing layer. 
         [0017]    In an embodiment, the polyethylene tape further includes a release layer, wherein the release layer contains a release agent, and is attached to the first backing layer, so that the first backing layer is between the release layer and the second backing layer. 
         [0018]    No matter the polyethylene tape is reeled up into a roll or not, the first and the third backing layers may isolate the second backing layer from the adhesive layer to avoid the drawbacks of the conventional PVC tape. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0019]    The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which 
           [0020]      FIG. 1  is an exploded view of a first preferred embodiment of the present invention; 
           [0021]      FIG. 2  is a perspective view of the first preferred embodiment of the present invention, showing the roll of the polyethylene tape; 
           [0022]      FIG. 3  is an exploded view of a second preferred embodiment of the present invention; 
           [0023]      FIG. 4  is an exploded view of a third preferred embodiment of the present invention; 
           [0024]      FIG. 5  is an exploded view of a fourth preferred embodiment of the present invention; 
           [0025]      FIG. 6  is an exploded view of a fifth preferred embodiment of the present invention; and 
           [0026]      FIG. 7  is an exploded view of a sixth preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0027]    As shown in  FIG. 1 , a polyethylene tape of the first preferred embodiment of the present invention includes a first backing layer  11 , a second backing layer  12 , a third backing layer  13 , and an adhesive layer  14 . 
         [0028]    The first backing layer  11  is a polyethylene (PE) film, and is made by injection molding. The first backing layer  11  is transparent, and is not colored. The reason of why the first backing layer  11  is made of PE is that PE lacks an odor and nontoxic, and furthermore, PE is stable in low temperature, and has a superior performance in chemical stability and acid/alkali resistance. Moreover, PE will be brittle after exposure under the sun for a long time, and generate CO 2  and H 2 O after burning. In other words, PE generates less pollution, and is recyclable. 
         [0029]    The second backing layer  12  is a polyethylene (PE) film as well, and is bonded to the first backing layer  11  by injection molding. The second backing layer  12  is colored by a recyclable white dye. Except white, the second backing layer  12  can be any color, such as black, red, and yellow, to facilitate identification. 
         [0030]    The third backing layer  13  is a polyethylene (PE) film as well, and is bonded to the second backing layer  12  by injection molding. As a result, the second backing layer  12  is sandwiched by the first and the third backing layers  11 ,  13 . The third backing layer  13 , the same as the first backing layer  11 , is transparent, and is not colored. 
         [0031]    The adhesive layer  14  is recyclable acrylic glue coated on an exterior side of the third backing layer  13 . In other words, the third backing layer  13  is between the second backing layer  12  and the adhesive layer  14 . A thickness of the adhesive layer  14  is less than a sum of thicknesses of the first, the second, and the third backing layers  11 ,  12 ,  13 , and more preferable, the thickness of the adhesive layer  14  is less than the thicknesses of the first, the second, and the third backing layers  11 ,  12 ,  13  respectively. The reason of selecting recyclable acrylic glue is that acrylic glue has no solvent, and has a high affiliation with PE. With the thickness limitation of above, the adhesive layer  14  is firmly bonded to the third backing layer  13  without the adhesive flow problem. 
         [0032]    As a result, the third backing layer  13  isolates the second backing layer  12  from the adhesive layer  14  to avoid affiliation of the dye in the second backing layer  12  and the adhesive layer  14 . Besides, when the PE tape is reeled up into a roll, the adhesive layer  14  is attached to the first backing layer  11 . In this condition, the second backing layer  12  and the adhesive layer  14  are isolated by the first backing layer  11 , and the same function will arise to avoid affiliation of the dye in the second backing layer  12  and the adhesive layer  14 . Both the first and the third backing layers  11 ,  13  are transparent which may show the color of the second backing layer  12 . 
         [0033]    When the PE tape of the first preferred embodiment of the present invention is attached to an object, such as an aluminum window frame, the adhesive layer  14  will be not left on the object if the PE tape is torn off. 
         [0034]    As shown in  FIG. 3 , a PE tape of the second preferred embodiment of the present invention, which is based on the first preferred embodiment, includes a first backing layer  11 , a second backing layer  12 , a third backing layer  13 , and an adhesive layer  14 . The PE tape of the second preferred embodiment further is printed with an ink layer  15  on an exterior side of the first backing layer  11 . The ink layer  15  is made of a recycle material, and the first backing layer  11  is between the first second backing layer  12  and the ink layer  15 . The ink layer  15  could texts, icons, warnings, and brand names for labeling, warning, and adverting. In the second preferred embodiment, the ink layer  15  has blue texts, and preferable, the color of the ink layer  15  is different from the color of the second backing layer  12 . 
         [0035]      FIG. 4  shows a PE tape of the third preferred embodiment of the present invention, which is based on the second preferred embodiment, including a first backing layer  11 , a second backing layer  12 , a third backing layer  13 , an adhesive layer  14 , and an ink layer  15 . Except that, the PE tape of the third preferred embodiment further includes a release layer  16 . The release layer  16 , which contains a release agent, is attached to the exterior side of the first backing layer  11  to cover the ink layer  15 , and therefore the ink layer  15  is sandwiched by the first backing layer  11  and the release layer  16 . The release layer  16  may be made of polyethylenimine (PEI), polyethylene terephthalate (PET), silicon oil, silicon rubber, or any material having a low affiliation with the adhesive layer  14 . 
         [0036]    When the PE tape is reeled up into a roll, the adhesive layer  14  is attached to the release layer  16  instead of the ink layer  15 . It could prevent the ink layer  15  from transferring to the adhesive layer  14 . In addition, the adhesive layer  14  will not left on the release layer  16  because of the low affiliation property while the PE tape is pulled out from the roll. It could keep the adhesion of the adhesive layer  14  as well as provide a good usage to the user. 
         [0037]      FIG. 5  shows a PE tape of the fourth preferred embodiment of the present invention, which is based on the third preferred embodiment, including a first backing layer  11 , a second backing layer  12 , a third backing layer  13 , an adhesive layer  14 , an ink layer  15 , and a release layer  16 . Except that, the PE tape of the third preferred embodiment further includes an antistatic layer  17  between the ink layer  15  and the release layer  16 . In the present embodiment, the antistatic layer  17  is made of a conductive material, such as polythiophene (PT), carbon nanotube (CNT), and grapheme. The antistatic layer  17  may eliminate electrostatics on the release layer  16  to keep the function of the release layer  16 . 
         [0038]      FIG. 6  shows a PE tape of the fifth preferred embodiment of the present invention, including a first backing layer  11 , a second backing layer  12 , a third backing layer  13 , an adhesive layer  14 , and a release layer  16 . The first backing layer  11  of the fifth preferred embodiment is not printed with the ink layer, so that the first backing layer  11  is between the second backing layer  12  and the release layer  16 .  FIG. 7  shows a PE tape of the sixth preferred embodiment of the present invention, including a first backing layer  11 , a second backing layer  12 , a third backing layer  13 , an adhesive layer  14 , a release layer  16 , and an antistatic layer  17 . The antistatic layer  17  is attached to the first backing layer  11 , and then the release layer  16  is attached to the antistatic layer  17 , so that the antistatic layer  17  is between the first backing layer  11  and the release layer  16 . It may avoid the problems of adhesive flow and residual adhesive. It also may avoid the dye from transferring to the adhesive layer  14 . 
         [0039]    Moreover, the PE tapes of above preferred embodiments could be further provided with a release sheet (not shown) attached to the adhesive layer  14 , so that the adhesive layer  14  is between the third backing layer  13  and the release sheet. The release sheet gives the adhesive layer  14  a further protection. 
         [0040]    In conclusion, the PE tape of the present invention is recyclable, and has no drawback of the conventional PVC tape. It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent structures which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention.