Patent Publication Number: US-2004048103-A1

Title: Extruded plastic tape

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001] Not Applicable  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002] Not Applicable  
       REFERENCE TO MICROFICHE APPENDIX  
       [0003] Not Applicable  
       BACKGROUND OF THE INVENTION  
       [0004] 1. This invention is directed to an extruded plastic tape having a light reactive surface that may include a crenelated surface of irregular formation, and tapered edges; the tape having a wide range of visual, decorative and practical uses, with strong safety aspects.  
       [0005] 2. There exists a widespread need for convenient, how-cost safety markers, with particular emphasis on high visibility, particularly in conditions of darkness or poor lighting.  
       [0006] The fluorescent and reflective tapes presently available are mainly characterized by being self adhesive and being possessed of limited visibility, in that the orientation to the viewer of the surface to which such tape is adhered, is critical.  
       [0007] One of the major advantages of plastic is its flexibility and ease of fabrication by way of extrusion. However, one of the disadvantages of this is that an extremely uniform product is consistently produced, the uniformity of which diminishes its attraction for many decorative applications.  
       [0008] Furthermore, the production of plastics materials through a die has led to a longitudinally smooth surface, formed in conformity with the die surface. While in many uses this is favourable, in some instances this smooth surface is highly undesirable, as it may be very slippery, when positioned on the ground.  
       BRIEF SUMMARY OF THE INVENTION  
       [0009] It has been found that a group of plastics can be produced that include rare earth phosphors combined with fluorescent material, to provide a tape having unusual visibility in after-dark and in poor light conditions such as dusk and pre-dawn. The elastic nature of the selected plastics facilitates use of the tape as a marking medium, including use as a boundary or route marker, as well as a proximity marker for obstacles.  
       [0010] The cross-sectional profile form of one embodiment of the tape, by way of a tapered edge, facilitates its use upon the ground, and when freely suspended, promotes aerodynamic motion to enhance the visual prominence of the tape in a boundary or location marking function.  
       [0011] In one tape embodiment, when extruded through a die under carefully controlled conditions of temperature and extrusion rate, an irregular crenelated surface finish may be produced. In this case, while the ribbon width is constant, the surface between the ribbon edges is deformed out of the plane of the ribbon edges, in a non-repetitive pattern of random rib-like protrusions, interspersed with marked, non-protruding surface portions having a shirred ‘gekko’-like appearance, somewhat akin to the look of the skin of the foot of a Gecko lizard or of lace curtaining.  
       [0012] One use of this novel section is as a vertical venetian blind. Another contemplated use is as an an elastic tie, wherein both the gripping and the elastic properties are of high capability. When used on the ground, the rough face constitutes a non-skid surface. Giving the tape section a fine tapered edge has been found to convey unusual aerodynamic characteristics. Thus, by suspending a length of such tape in a slightly twisted, tensioned condition between a pair of spaced supports it has been found that a marked dynamic twisting action occurs under slightly breezy conditions, with the visually prominent point of twist moving rapidly up and down the length of the tape.  
       [0013] Other, more standard profiles may incorporate the phosphor and fluorescent materials. 
     
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
     [0014] Certain embodiments of the invention are described by way of illustration, without limitation thereto other than as set forth in the accompanying claims, reference being made to the accompanying drawings, wherein:  
     [0015]FIG. 1 is a plan view of a first embodiment extruded tape in accordance with the present invention;  
     [0016]FIG. 1G is a plan view of a first embodiment extruded tape portraying the subject ‘gecko’ appearance;  
     [0017]FIG. 2 is a perspective view of a length of a second embodiment extruded tape in accordance with the present invention; and  
     [0018]FIG. 3 is a cross section of a third tape embodiment.  
     [0019]FIGS. 4 and 5 are cross-section views of further embodiments; and,  
     [0020]FIG. 6 is an elevational view of a support post for use with a driveway marker tape. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     [0021] Referring to the FIG. 1 embodiment, a short length of tape  10  is shown, having plain, substantially planar edge portions  12 . Irregular, randomly spaced raised “island” portions  14  arc distributed upon the surface of the centre portion  16  of the tape  10 , the portions  14  being substantially solid. The intervening spaces between the islands  14  arc covered with a series of very fine closely spaced ripple-like transversely extending protrusions  18 , giving a shirred lace-like visual appearance. FIG. 1G shows a series of very fine closely spaced ripple-like transversely extending larger protrusions  19 , giving a Gecko&#39;s foot-like visual appearance.  
     [0022] Turning to FIG. 2, a length of tape  20  having a cross sectional profile as shown in FIG. 3, with tapered edges  22  and a substantially planar intermediate portion  24 , is shown tied in tensioned relation between a pair of support posts.  
     [0023] The tape  20  has a twist  28  imparted by the supporting oords  29 . In use, the effect of a slight breeze is to cause twist  28  to displace up and down, along the length of the tape  20 .  
     [0024] The tapered-edge tape  20  or the tape  10  embodiment can be laid out on the ground and secured in place, to mark paths, pitches, dc, (or suspended to form a barrier) so as to delineatc or mark off designated or embargoed locations and areas.  
     [0025] The subject tapes may be extruded from plastic elastomers such as DuPont polyolefin “Engage” (T.M.)-8003, which is extremely weather resistant.  
     [0026] The introduction of phosphorescent pigments, such as GTA Inc, PL, S, R or M series or Lunbo Photo luminescent pigments to the mix results in tapes of long term light emissivity, up to as much as 12 hours to 20 hours duration, The phosphors include colours of light yellow, Light green, light White, red, orange, green and blue.  
     [0027] These phosphorescent pigments are non-toxic, non-radioactive, being free of any radioactive additives; and consist of alkaline aluminate, activated by rare earth ions.  
     [0028] The addition of a small percentage of fluorescent material or LISA-Light Collecting Plastics by Bayer AG significantly enhances the brightness of the lighte emission—particularly under poor light conditions of less than total darkness.  
     [0029] The addition of a small percentage aluminum “giitter niblets” to the surface of the tape provides an effective reflective characteristic to the tape, when illuminated such as by vehicle headlights.  
     [0030] In one polyolefin embodiment, the addition of a U/V stabilizer, such as 1% by weight of a hundred amine, combined with 20-weight percent of rare earth yellow-green phosphorescent, plus one half weight percent of a green fluorescent, produced a tape with a high degree of brightness and extended emissivity.  
     [0031] Giving the tape section a fine tapered edge has been found to convey unusual aerodynamic characteristics. By suspending a length of such tape in a slightly twisted, tensioned condition between a pair of spaced supports it has been found that a most dynamic twisting action occurs under slightly breezy conditions with the visually prominent point of twist moving rapidly up and down along the tape.  
     [0032] The inclusion of a phosphorescent element into the melt from which the extrusion is made results in a visually prominent locator/indicator marker, readily identified in the dark.  
     [0033] One use, with safety implications, is as a route or boundary marking means, which can include the corridors of hospitals, nursing homes, resident&#39;s rooms a line from bed to bathroom, the aisles of an aircraft, emergency exit routes, or the sidelines of sports fields, soccer pitches, etc.  
     [0034] Other uses include wearing by cyclist, pedestrians, road workers; the marking of boats and docks, marker buoys defining safe swimming pool boundaries. Such uses are greatly facilitated by the elastic nature of the tape.  
     [0035] The addition of a small percentage of fluorescent material to supplement the phosphorescent material has been found to significantly enhance the visual prominence of the tape under intermediate lighting conditions, such as at dusk or dawn.  
     [0036] Use of the material as a low level light source, such as emergency and night tight when applied to lamp shades/ceiling light fixtures, telephones or a route or boundary assistance for the visually impaired, is contemplated, particularly in view of the long period of emissivity achieved by the use of phosphorescent rare earth.  
     [0037] Light reflectivity of the material can be promoted by the addition of a small amount of aluminum glitter material. Protection against ultra-Violet (u/v) damage is generally incorporated. The use of phosphors combined with fluorescent material provide a tape having unusual visibility in-after-dark and poor light conditions such as at dusk and pre-dawn times.  
     [0038] The elastic nature of the selected plastics facilitates use of the tape as a marking medium, including use as a boundary or route marker, as well as a proximity marker for obstacles.  
     [0039] The cross sectional profile form of one embodiment of the tape, by way of a tapered edge, facilitates its use upon the ground and when freely suspended, promotes aerodynamic motion to enhance the visual prominence of the tape in a boundary or location marking function.  
     [0040] In one tape embodiment, when extruded through a die under carefully controlled conditions of temperature and extrusion rate, an irregular crenulated surface finish may be produced. In this case, while the ribbon width is constant, the surface between the ribbon edges is deformed out of plane of the ribbon, in a non-repetitive pattern of random rib-like protrusions, interspersed with marked, non-protruding surface portions having a shirred-like appearance, somewhat akin to the look of lace curtaining and rib-like folds similar to the skin of a Gecko.  
     [0041] One novel use is as a vertical Venetian blind. Another contemplated use is as an elastic tie and handle cushion grip wrap, which eliminates abrasive hardness &amp; vibration, for canes, walkers, tool handles, including motorized equipment such as chain saw and gas trimmers. etc wherein both the self-gripping and elastic properties are well utilized.  
     [0042] When used on the ground as a ground marker, the rough face of the tape forms a non-skid surface.  
     [0043]FIG. 4 shows a more standard, trim profile, and FIG. 5 shows a trim or tie profile, both of which may incorporate the phosphors and fluorescent materials.  
     [0044]FIG. 6 shows a ground spike having a split top-ring, into which the tape of FIG. 2 may be slid laterally. This enables the tape to be laid out on the ground, the ground spikes positioned as desired and driven into the ground, and the tape then slid laterally in supported relation within the split ring. The tape ends may be tied-off to the rings of the respective ground spikes.