METAL DETECTABLE POLYURETHANE FILM
20180281264 ยท 2018-10-04
Inventors
Cpc classification
B29C48/78
PERFORMING OPERATIONS; TRANSPORTING
B29L2007/008
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A metal and X-Ray detectable polyurethane film having metallic particles blended into the polyurethane when in a liquid form and then having the film extruded so as to fully embed the metallic particles, such as iron oxide, across all areas of the film, which can be used in protective clothing, such as reusable aprons and sleeve covers, for example, in food processing applications. In this manner, the film permits easy detection, and thus removal of, damaged film portions that become detached from the protective garment and inadvertently introduced into the food being processed, before the final processing and packaging thereof.
Claims
1. A metal detectable polyurethane film comprising: polyurethane heated to assume a form of a liquid film; a mixture having metallic particles therein blended into the liquid film, the mixture being extruded to embed the metallic particles across a length and width of the liquid film.
2. The metal detectable polyurethane film of claim 1, wherein the mixture further comprises from about 4% to 6% by weight percentage the metallic particles.
3. The metal detectable polyurethane film of claim 1, wherein the mixture further comprises from about 2% to 7% by weight percentage the metallic particles.
4. The metal detectable polyurethane film of claim 1, wherein the mixture further comprises resins, barium, pigments, lubricants, chromium, calcium, silicon, carbon, titanium and colorants.
5. The metal detectable polyurethane film of claim 1, wherein the film is X-Ray detectable.
6. The metal detectable polyurethane film of claim 5, wherein the metallic particles are iron oxide.
7. A method for manufacturing a metal detectable polyurethane film, the method comprising: heating polyurethane to become a liquid film; blending a mixture having metallic particles therein into the liquid film; and extruding the mixture to embed the metallic particles across a length and width of the liquid film.
8. The method for manufacturing a metal detectable polyurethane film of claim 7, further comprising the step of providing the mixture with from about 4% to 6% by weight percentage of the metallic particles.
9. The method for manufacturing a metal detectable polyurethane film of claim 7, further comprising the step of providing the mixture with from about 2% to 7% by weight percentage of the metallic particles.
10. The method for manufacturing a metal detectable polyurethane film of claim 7, further comprising the step of providing the mixture with quantities of resins, barium, pigments, lubricants, chromium, silicon, carbon and titanium.
11. The method for manufacturing a metal detectable polyurethane film of claim 7, wherein the metallic particles are iron oxide.
12. The method for manufacturing a metal detectable polyurethane film of claim 7, wherein the film is X-Ray detectable.
13. A method for manufacturing a metal detectable polyurethane film, the method comprising: heating polyurethane to become a liquid film; blending a mixture having metallic particles therein into the liquid film; and extruding the mixture to embed the metallic particles across a length and width of the liquid film, the mixture having from about 2% to 7% by weight percentage of the metallic particles.
14. The method for manufacturing a metal detectable polyurethane film of claim 13, wherein the metallic particles are iron oxide.
15. The method for manufacturing a metal detectable polyurethane film of claim 14, wherein the film is X-Ray detectable.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The embodiments of the present invention will now be described by reference to the following figure, and in which:
[0010]
DETAILED DESCRIPTION OF THE INVENTION
[0011] The invention will be described for the purposes of illustration only in connection with certain embodiments; however, it is to be understood that other objects and advantages of the present invention will be made apparent by the following description of the drawings according to the present invention. While a preferred embodiment is disclosed, this is not intended to be limiting. Rather, the general principles set forth herein are considered to be merely illustrative of the scope of the present invention and it is to be further understood that numerous changes may be made without straying from the scope of the present invention.
[0012] The present invention relates to a metal and X-Ray detectable polyurethane film for use in protective garments or clothing, such as reusable aprons and sleeve covers, ideally in food processing facilities and food manufacturing sites, though it will be understood that variations as this use are possible. In an exemplary embodiment, solid forms of polyurethane are heated to assume the form of a liquid film, and then a mixture having metallic particles, such as (but not limited to) iron oxide, therein is blended into the liquid film. The mixture is then extruded, such as by conventional means which would be known to one skilled in the art, to embed the metallic particles in the mixture across a length and width of the liquid film.
[0013] In an exemplary embodiment, the mixture, in addition to the metallic particles (such as iron oxide) therein, can also further contain, but is not limited to, quantities of resins, pigments, barium lubricants, calcium, chromium, silicon, carbon, titanium and colorants (which may be present in a letdown ratio of about 15%, so this too can be varied). It will be understood that variations to this ratio are possible, and that quantities of each of these components in the mixture can be varied. In a further embodiment, the mixture comprises from about 4% to 6% by weight percentage of metallic particles, such as iron oxide, though variations to this are possible, such as the mixture having about 2% to 7% by weight percentage of metallic particles.
[0014] Referring to
[0015] In manufacturing the film of the present invention, a base polyether polyurethane resin is sent to a compounder, which re-pelletizes the resin, and encapsulating metallic particles, such as iron oxide powder, into these polyurethane pellets.
[0016] Once a detectable film is desired, along with an indication the approximate active percentage of detectable material desired in the final film to be processed, a calculation is done to determine how many pounds of metallic particles (such as iron oxide) must be blended in to, for example, each 100 lbs. of resin (along with other additives) to achieve a desired final percentage of detectable materials in the film to be processed.
[0017] The base polyether polyurethane resin (and the additives) is then blended with the metallic particles (such as iron oxide) at the desired ratio together in a large batch blender. This is then blended for a specified period and then vacuum loaded into a drying hopper above an extruder.
[0018] As the blend is being loaded into the drying hopper, and after the loading is complete, the batch is then dehumidified by desiccant dryers at elevated temperatures until the blend reaches a certain dew point, indicating that it is dry enough to then be fed into the extruder to make film. A gate at the bottom of the hopper is then opened and the batch is gravity fed into the extruder.
[0019] It will be apparent to those skilled in this art that various modifications and variations may be made to the embodiments disclosed herein. Other embodiments consistent with the present invention will become apparent from consideration of the specification and the practice of the invention disclosed therein.
[0020] Accordingly, the specification and the embodiments are to be considered exemplary only, with a true scope of the invention being disclosed by the following claims.