Source: https://patents.google.com/patent/US20040256050
Timestamp: 2018-04-22 10:47:25
Document Index: 96652361

Matched Legal Cases: ['art 420', 'art 522', 'art 606', 'art 614', 'art 700', 'art 702']

US20040256050A1 - Forming evacuation channels during single and multi-layer extrusion process - Google Patents
US20040256050A1
US20040256050A1 US10801950 US80195004A US2004256050A1 US 20040256050 A1 US20040256050 A1 US 20040256050A1 US 10801950 US10801950 US 10801950 US 80195004 A US80195004 A US 80195004A US 2004256050 A1 US2004256050 A1 US 2004256050A1
US7517484B2 (en )
[0005]FIG. 1 illustrates a prior art production line 100 for manufacturing vacuum packaging film. Included is a roll of unprocessed vacuum packaging film 102, roller 104 and patterned wheel 106. Directional arrow 108 indicates how roll 102 is unfurled as roller 104 turns in the direction of arrow 110. As an unfurled sheet 111 of roll 102 passes between roller 104 and patterned wheel 106, wheel 106 also turns as indicated by direction arrow 112. As a result of mechanical pressure, the unfurled portion 111 is embossed with the pattern on patterned wheel 106 and formed into a patterned vacuum packaging film 114.
[0007]FIG. 2 illustrates another prior art manufacturing line 200 for manufacturing vacuum packaging film. Included in the manufacturing line 200 is a roll of substrate 202, a single layer extruder 204, a roller 206 and a cooling roller 208 embedded with a reverse pattern. As unfurled substrate 210 is drawn out from roll 202 by rollers 206 and 208, indicated by directional arrows 212, 214 and 216, a plastic melt 218 is exuded from single layer extruder 204 onto the unfurled substrate 210. As the melt 218 and unfurled substrate 210 passes over cooling roller 208, the melt 218 solidifies and is simultaneously embedded, along with the unfurled substrate 210, by the inverse pattern located on cooling roller 208. As a result, multi-layered/patterned vacuum packaging film 220 emerges.
[0018]FIG. 1 illustrates a prior art method for manufacturing vacuum packaging film.
[0019]FIG. 2 illustrates another prior art method for manufacturing vacuum packaging film.
[0020]FIG. 3 illustrates an apparatus for manufacturing vacuum packaging film utilizing a multi-layer extruder, in accordance with the present invention.
[0021]FIG. 4 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder, in accordance with the present invention.
[0022]FIG. 5 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder, in accordance with the present invention.
[0023]FIG. 6 illustrates an apparatus for manufacturing vacuum packaging film utilizing a multi-layer extruder and a cooling plank, in accordance with the present invention.
[0024]FIG. 7 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder and a cooling plank, in accordance with the present invention.
[0025]FIG. 8 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder and a cooling plank, in accordance with the present invention.
[0026]FIG. 9 illustrates an apparatus for manufacturing vacuum packaging film utilizing a multi-layer extruder and an air-knife, in accordance with the present invention.
[0027]FIG. 10 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder and an air-knife, in accordance with the present invention.
[0028]FIG. 11 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder and an air-knife, in accordance with the present invention.
[0029]FIG. 12 illustrates an apparatus for manufacturing vacuum packaging film utilizing a multi-layer extruder and an inverse-vacuum, in accordance with the present invention.
[0030]FIG. 13 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder and an inverse-vacuum, in accordance with the present invention.
[0031]FIG. 14 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder and an inverse-vacuum, in accordance with the present invention.
[0032]FIG. 15 is a flowchart illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder, a rotating roller and a pattern imparting means, in accordance with the present invention.
[0033]FIG. 16 illustrates a cross-section of a vacuum packaging film sheet in accordance with one embodiment of the present invention.
[0034]FIG. 17 illustrates a vacuum packaging film sheet having a zigzag pattern in accordance with yet another embodiment of the present invention.
[0035]FIG. 18 illustrates a bag roll of vacuum packaging material having a zigzag pattern in accordance with the present invention.
[0036]FIG. 19 illustrates a preformed vacuum packaging receptacle having a zigzag pattern in accordance with the present invention.
[0037]FIGS. 1-2 were described in reference to the prior art. The present invention provides a method and apparatus for economically producing a multi-layer, patterned vacuum packaging film. By utilizing a multi-layer extruder, as opposed to the single-layer extruder of the prior art, with a variety of patterning techniques, the desired vacuum packaging film is achieved. The patterning techniques include using a patterned cooling roll, a patterned cooling plank, an air-knife and an inverse-vacuum. These techniques will be now be described. It should be kept in mind that certain extraneous details were left out of the subsequent description in an effort to not unnecessarily obscure the true spirit and scope of present invention.
[0038]FIG. 3 illustrates an apparatus 300 for manufacturing vacuum packaging film in accordance with one embodiment of the present invention. The apparatus 300 includes a multi-layer extruder 302 and a patterned cooling roller 308 embedded with a reverse pattern. The multi-layer extruder 302 is capable of extruding layers as required by the specific application. One suitable layer configuration is described below in more detail with reference to FIG. 15. although at least one improved pattern is described below with reference to FIG. 16. As the multi-layer extruder 302 extrudes a plastic melt 304, the plastic melt 304 flows into contact with the cooling roller 208 turning in the direction of an arrow 214. As the melt 304 is cooled, a pattern is also formed on the melt 304 at the same time due to the presence of the inverse-pattern. As a result, a multi-layer vacuum packaging film 306 emerges.
[0042]FIG. 4 is a flowchart illustrating a method 310 for manufacturing vacuum packaging film utilizing a multi-layer extruder, in accordance with the present invention. As will be appreciated, multi-layer films of the prior art were formed through embossing multiple layers together. In the method 310, multi-layer films are formed through a multi-layer extrusion process. After a start operation 312 prepares material as necessary, a plastic melt is flowed from a multi-layer extruder onto a rotating cooling roller, at step 314. At step 316, the plastic cools on the rotating cooling roller and turns into the vacuum packaging film. The process then ends at a step 318 where additional manufacturing may be performed. As will be appreciated, patterning can be performed later if desired, or as next described in FIG. 5, the cooling roller can be patterned and thus the film is formed with a pattern during the extrusion process.
[0043]FIG. 5 is a flowchart illustrating a method 320 for manufacturing a patterned vacuum packaging film utilizing a multi-layer extruder, in accordance with the present invention. After a start step 322, a plastic melt, generated by a multi-layer extruder, is flowed onto a patterned rotating cooling roller at step 324. The rotating roller has an inverse pattern embedded on it. As the melt is cooled on the cooling roller, the inverse pattern imparts a pattern onto the congealing melt that solidifies into a patterned multi-layer vacuum packaging film, at step 326. The process then ends at step 328.
[0044]FIG. 6 illustrates an apparatus 400 for manufacturing a multi-layer patterned vacuum packaging film in accordance with another embodiment of the present invention. The apparatus 400 includes a multi-layer extruder 302, a patterned cooling plank 402, and a cooling roller 404 that rotates in the direction of arrow 406. As the plastic melt 304 flows along cooling plank 402, the melt 304 congeals and is simultaneously imprinted with the inverse of the pattern present on the cooling plank 402. As a result, a multi-layered, patterned vacuum packaging film 306 emerges, as roller 404 pulls along the film 306. Again, the apparatus 400 may include a laminating roll applied on the plank 402 and/or on the cooling roller 404. There may also be additional temperature and/or speed controls.
[0045]FIG. 7 is a flowchart illustrating a method 408 for manufacturing vacuum packaging film utilizing a multi-layer extruder and a cooling plank, in accordance with the present invention. After a beginning step 410, a plastic melt is flowed from a multi-layer extruder onto a cooling plank at step 412. The melt cools as it flows over the cooling plank and forms a vacuum packaging, at step 414. As will be appreciated, a roller or other source of motion must be used to maintain flow of the plastic melt across the cooling plank. The process finishes at step 416.
[0046]FIG. 8 is a flowchart illustrating a method 418 for manufacturing a multi-layer patterned vacuum packaging film utilizing a multi-layer extruder and a cooling plank, in accordance with the present invention. After start 420, a multi-layer extruder forms a plastic melt that flows out onto a patterned cooling plank, at step 422. The cooling plank has an inverse pattern on it that imparts a pattern onto the melt as it flows over the plank and forms a vacuum packaging film, at step 424. The process terminates at step 426.
[0047]FIG. 9 illustrates an apparatus 500 for manufacturing vacuum packaging film utilizing a single or multi-layer extruder and an air-knife, in accordance with the present invention. The apparatus 500 includes a single or multi layer extruder 508, an airknife 504, and a cooling roller 404 that turns in the direction of arrow 406. As the plastic melt 304 flows onto roller 404, the air-knife 504 selectively etches a pattern onto the melt 304 with controlled blasts of air 506. Additionally, blasts of air 506 also cause the melt 304 to congeal into multi-layered, patterned vacuum packaging film 306 that is pulled along by roller 404, in the instance where extruder 508 is a multi-layer extruder 508. If a single layer extruder 508 is used, a single layer, patterned vacuum packaging film 306 is produced.
[0048]FIG. 10 is a flowchart illustrating a method 510 for manufacturing vacuum packaging film utilizing a multi-layer extruder and an air-knife, in accordance with the present invention. The method begins at step 512 and proceeds to step 514 where a plastic melt is flowed from a multi-layer extruder, in the vicinity of an air-knife. At step 516, the air-knife cools the plastic melt and a vacuum packaging film results. Step 518 terminates the process.
[0049]FIG. 11 is a flowchart illustrating a method 520 for manufacturing patterned multi-layer vacuum packaging film utilizing a multi-layer extruder and an air-knife, in accordance with the present invention. After start 522, a plastic melt flows from a multi-layer extruder in the vicinity of an air-knife at step 524. A pattern is then formed in the melt by the air-knife as it is cooled into a vacuum packaging film, at step 526. The process then ends at 528.
[0050]FIG. 12 illustrates an apparatus 600 for manufacturing vacuum packaging film utilizing in accordance with one embodiment of the present invention. The apparatus 600 includes a multi-layer extruder 302 and a cooling roller 404 having an inverse-vacuum 602. As the plastic melt 304 flows onto the cooling roller 404, the inverse-vacuum 602 selectively “pulls” a pattern onto the melt 304. Additionally, inverse vacuum 602 causes the melt 304 to congeal into multi-layered, patterned vacuum packaging film 306 that is pulled along by roller 404 in the direction of the rotation 406. Alternatively, the pattern may be formed geometrically on the cooling roller 404 and the inverse vacuum 602 may simply hold the plastic melt 304 onto the patterned roller 404.
[0051]FIG. 13 is a flowchart illustrating a method 604 for manufacturing vacuum packaging film utilizing a multi-layer extruder and an inverse-vacuum, in accordance with the present invention. After start 606, a plastic melt is flowed from a multi-layer extruder onto a roller with an inverse vacuum at step 608. The melt then cools as it flows over the roller and turns into a vacuum packaging film at step 610. At 612, the process ends.
[0052]FIG. 14 is a flowchart 614 illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder and an inverse-vacuum, in accordance with the present invention. The method begins at 616 and proceeds to step 618 where a plastic melt is produced from a multi-layer extruder onto a roller with an inverse-vacuum. The melt then cools as it flows over the roller and is simultaneously imprinted with a pattern due to the presence of the inverse vacuum at selected points of the roller. As a result of the preceding, a vacuum packaging film is formed at step 622. The process then terminates at step 622.
[0053]FIG. 15 is a flowchart 700 illustrating a method for manufacturing vacuum packaging film utilizing a multi-layer extruder, a rotating roller and a pattern imparting means, in accordance with the present invention. After start 702, a multi-layer extruder forms a plastic melt that is flowed over a roller at step 704. The melt is then cooled and simultaneously imprinted with a pattern, at step 706, to form a vacuum packaging film. The pattern is delivered via a pattern imprinting means. The process then ends at step 708.
[0057]FIG. 18 illustrates a bag roll 820 of vacuum packaging material in accordance with yet another embodiment of the present invention. The bag roll 820 includes a first sheet of patterned film 800, a second sheet of film 822, and heat sealed opposing sides 824. The bag roll 820 is useful by those such as end consumers in creating vacuum packaging bags of varying sizes. The patterned film sheet 800 may have a zigzag or other type of pattern. The second film sheet 822 may be formed with or without patterns, either way the pattern of the film sheet 800 aids in evacuation by forming airchannels during vacuum evacuation.
[0058]FIG. 19 illustrates vacuum packaging receptacle 830 in accordance with yet another embodiment of the present invention. The vacuum packaging receptacle 830 includes a patterned film sheet 800, a second film sheet 832, and three sealed edges 834. The patterned film sheet 800 may have a zigzag or other type of pattern. The second film sheet 832 may be formed with or without patterns, either way the pattern of the film sheet 800 aids in evacuation by forming airchannels during vacuum evacuation.
1. A method for manufacturing a multi-layer film for use in vacuum packaging applications, said multi-layer film having a pattern that operates to form channels suitable for evacuation of gas when said multi-layer film is used in the creation of a vacuum packaging bag, said method comprising the acts of:
heat-extruding a second material onto said spinning cooling roll such that said first and second extruded materials bond and form first and second layers of said multi-layer film during a cooling of said first and second extruded materials; and
8. A method for manufacturing a multi-layer film as recited in claim 7, further including the act of positioning a laminating roll to apply pressure to the extruded materials in order to apply said pattern formed on the circumferential surface of said cooling roll onto said multi-layer film.
9. A method for manufacturing a multi-layer film as recited in claim 8 further including the act of controlling a temperature of said cooling roll in order to properly effectuate cooling and formation of said first and second layers.
10. A method for manufacturing a multi-layer film as recited in claim 1, wherein the act of applying a pattern to said extruded layers is accomplished by extruding said materials over a patterned cooling plank which in turn directs said extruded materials to flow over said cooling roll.
11. A method for manufacturing a multi-layer film as recited in claim 2, further including the act of controlling a temperature of said cooling plank to properly effectuate cooling and formation of said first and second layers.
13. A method for manufacturing a multi-layer film as recited in claim 1, wherein said channels formed by said pattern have a varying width thereby retarding fluid flow therethrough.
14. A method for manufacturing a vacuum packaging bag, said method comprising:
b) bonding a second film sheet onto said first film sheet via sealing opposing sides to form a pouch with two open ends,
19. A method for manufacturing a roll of vacuum packaging bag material, said method comprising:
21. An apparatus for manufacturing a multi-layer film for use in vacuum packaging applications, said multi-layer film having a pattern that operates to form channels suitable for evacuation of gas when said multi-layer film is used in the creation of a vacuum packaging bag, said apparatus comprising:
a cooling roll positioned with respect to said extruder such that said extruder applies said first and second materials onto a circumferential surface of said cooling roll such that said first and second extruded materials bond and form first and second layers of said multi-layer film during a cooling of said first and second extruded materials, and
22. An apparatus as recited in claim 21, wherein said extruder is a melt-extrusion extruder.
23. An apparatus as recited in claim 21, wherein said extruder further includes a nozzle arranged to apply said first and second materials.
24. An apparatus as recited in claim 21, wherein said first material is a heat-sealable resin and said apparatus further includes a source of said heat-sealable resin coupled to said multi-layer extruder.
26. An apparatus as recited in claim 21, wherein said pattern forming mechanism includes a patterned formed on said circumferential surface of said cooling roll.
27. An apparatus as recited in claim 26, wherein said pattern on said circumferential surface of said cooling roll is an uneven pattern.
28. An apparatus as recited in claim 26, wherein said pattern on said circumferential surface of said cooling roll is a wave pattern.
29. An apparatus as recited in claim 26, wherein said pattern on said circumferential surface of said cooling roll is a striped pattern.
31. An apparatus as recited in claim 21, wherein said pattern forming mechansim includes a patterned cooling ramp disposed between said multi-layer extruder and said cooling roll.
34. An apparatus as recited in claim 21 further comprising a laminating roll arranged to assist in holding said first material onto said cooling roll.
36. An apparatus as recited in claim 34, wherein a cooling roll diameter is about 1.5 to 3 times larger than a laminating roll diameter.
37. An apparatus as recited in claim 34 wherein said extruder, cooling roll, and laminating roll are arranged to accept an outer layer in conjunction with said extruded first material, such that said inner layer and said outer layer are laminated in between the cooling roll and the laminating roll to form said multi-layer film.
38. An apparatus for manufacturing a multi-layer film for use in vacuum packaging applications, said multi-layer film including an inner layer having a plurality of grooves which operate to form channels suitable for evacuation of gas when said multi-layer film is used in the creation of a vacuum packaging bag, said apparatus comprising:
a single layer heat-extruder having a nozzle for melt extruding a heat-sealable resin suitable for forming said inner layer of said multi-layer film,
a cooling roll positioned with respect to said extruder nozzle such that said extruder applies said heat-sealable resin onto a circumferential surface of said cooling roll, said cooling roll formed having a pattern on said circumferential surface of said cooling roll which gives shape to said plurality of grooves on said inner layer, said cooling roll including steel;
a temperature controller for controlling a temperature of said cooling roll in order to properly effectuate cooling and formation of said heat-sealable resin into said grooved inner layer;
a laminating roll arranged to assist in holding said first material onto said cooling roll, said laminating roll having a diameter smaller than a diameter of said cooling roll; and
wherein said extruder, cooling roll, and laminating roll are arranged to accept an outer layer in conjunction with said extruded first material, such that said inner layer and said outer layer are laminated in between the cooling roll and the laminating roll to form said multi-layer film.
39. A multi-layer film suitable for use in forming a vacuum packaging bag, said multi-layer film comprising:
a patterned inner layer formed of a first material, said patterned inner layer having a plurality of grooves which operate to form channels suitable for evacuation of gas when said multi-layer film is used to form a vacuum packaging bag, said inner layer formed through heat extrusion of said first material onto a patterned cold roll, whereby said inner layer has a substantially uniform distribution of material, whereby said inner layer substantially lacks deformities typically present in an embossed film having a similar pattern formed by an embossing process; and
41. A multi-layer film as recited in claim 40, wherein said heat-sealable resin is a polyethylene resin.
43. A multi-layer film as recited in claim 39, wherein said pattern is a wave pattern.
47. A multi-layer film as recited in claim 39, wherein said pattern is a zigzag pattern.
48. A heat-sealable vacuum packaging bag for holding food or other product, said heat-sealable vacuum packaging bag comprising:
a patterned inner layer formed of a heat-sealable resin, said patterned inner layer having a plurality of grooves which operate to form channels suitable for evacuation of gas when said multi-layer film is used to form said vacuum packaging bag, said inner layer formed through heat extrusion of said first material onto a patterned cold roll, whereby said inner layer has a substantially uniform distribution of material substantially lacking deformities normally present in an embossed film having a pattern formed by an embossing process; and
a second sheet formed of said multi-layer plastic film, said second sheet having a footprint substantially similar to said first sheet; and
said first and second sheets arranged with respective patterned inner layers facing one another, said first and second sheets heat-sealed on opposing lateral sides and at an end side,
49. A heat-sealable vacuum packaging bag for holding food or other product, said heat-sealable vacuum packaging bag comprising:
a patterned inner layer formed of a heat-sealable resin, said patterned inner layer having an opposing zigzag pattern operable to form varying width channels suitable for evacuation of gas when said multi-layer film is used to form said vacuum packaging bag, whereby said varying width channels tend to retard fluid flow during vacuum evacuation of said vacuum packaging bag; and
an outer layer coupled to said patterned inner layer, said outer layer including a gas impermeable material,
said first and second sheets arranged with said patterned inner layer internal to said heat-sealable vacuum packaging bag, said first and second sheets sealed on opposing lateral sides and at an end side,
52. A vacuum packaging bag as recited in claim 49, wherein said first and second sheets are sealed via pressure sealing.
53. A heat-sealable vacuum packaging bag for holding food or other product, said heat-sealable vacuum packaging bag comprising:
an outer layer laminated onto said patterned inner layer, said outer layer including a gas impermeable material,
a second sheet including a gas impermeable material, said second sheet having a footprint substantially similar to said first sheet, said second sheet having an unpatterned inner layer made of a heat-sealable resin; and
said first and second sheets arranged with respective inner layers facing one another, said first and second sheets heat-sealed on opposing lateral sides and at an end side,
54. A bag roll suitable for forming heat-sealable vacuum packaging bags for holding food or other product, said bag roll comprising:
a second sheet formed of said multi-layer plastic film and having a shape and size substantially similar to said first sheet; and
said first and second sheets arranged with respective patterned inner layers facing one another, said first and second sheets heat-sealed on opposing lateral sides,
55. A method for making a multi-layer vacuum packaging film comprising:
flowing a plastic melt, from a multi-layer extruder, onto a rotating cooling roller; and
flowing a plastic melt, from a multi-layer extruder, onto a cooling plank;
cooling said plastic melt, as it flows over said cooling plank, into a vacuum packaging film.
flowing a plastic melt, from a multi-layer extruder, in said vicinity of an air-knife; and
cooling said plastic melt, as it flows in said vicinity of said air-knife, into a vacuum packaging film.
61. A method as recited in claim 60 wherein said air-knife is an inverse-vacuum.
62. A method as recited in claim 60 wherein said air-knife imparts a pattern onto said vacuum packaging film.
64. A method as recited in claim 60 wherein said multi-layer extruder is a single layer extruder.
65. An apparatus for producing a vacuum packaging film comprising:
a multi-layer extruder for producing a plastic melt; and
a pattern imparting means for imprinting a pattern onto said plastic melt as it congeals into said vacuum packaging film.
US20040256050A1 true true US20040256050A1 (en) 2004-12-23
US7517484B2 US7517484B2 (en) 2009-04-14