Co-extruded multi-layer tube for use in forming flexible bags
11141965 · 2021-10-12
Assignee
Inventors
Cpc classification
B65B1/04
PERFORMING OPERATIONS; TRANSPORTING
Y10T428/1341
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B32B2597/00
PERFORMING OPERATIONS; TRANSPORTING
Y10T428/1393
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
Y10T428/31797
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B32B2553/00
PERFORMING OPERATIONS; TRANSPORTING
B29K2995/0012
PERFORMING OPERATIONS; TRANSPORTING
B29C48/21
PERFORMING OPERATIONS; TRANSPORTING
Y10T428/31743
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B29L2031/712
PERFORMING OPERATIONS; TRANSPORTING
B32B2270/00
PERFORMING OPERATIONS; TRANSPORTING
B32B7/12
PERFORMING OPERATIONS; TRANSPORTING
B32B27/306
PERFORMING OPERATIONS; TRANSPORTING
B32B2250/246
PERFORMING OPERATIONS; TRANSPORTING
Y10T428/3175
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B32B27/308
PERFORMING OPERATIONS; TRANSPORTING
Y10T428/1324
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B32B2274/00
PERFORMING OPERATIONS; TRANSPORTING
B32B27/327
PERFORMING OPERATIONS; TRANSPORTING
B32B2250/40
PERFORMING OPERATIONS; TRANSPORTING
Y10T428/1383
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
Abstract
A multilayer film including a barrier layer, a sealing layer, and an alcohol barrier layer. The alcohol barrier layer includes cyclic olefin copolymer and is positioned between the barrier layer and the sealing layer. The multilayer film can be used to form a pouch for containing an alcohol-based hand sanitizer.
Claims
1. A multilayer film comprising: a barrier layer; a sealing layer; and an alcohol barrier layer; wherein the alcohol barrier layer is positioned between the barrier layer and the sealing layer; wherein the alcohol barrier layer comprises a cyclic olefin copolymer; and wherein the alcohol barrier layer is positioned directly between two polyethylene layers.
2. The multilayer film according to claim 1, wherein the barrier layer has a higher melting temperature than the sealing layer; wherein the barrier layer comprises polyamide, copolyamide, nylon 6, nylon 66, polyethylene terephthalate, polyester, polypropylene, medium density polyethylene, a polyolefin plastomer, a polyolefin elastomer, high density polyethylene, low density polyethylene, cyclic olefin copolymer, or blends thereof; and wherein the barrier layer has a thickness of 5 to 20 microns.
3. The multilayer film according to claim 1, wherein the sealing layer comprises polyethylene, a copolymer of ethylene, polypropylene, a copolymer of propylene, a polyolefin elastomer, a polyolefin plastomer, ethylene-vinyl acetate, low density polyethylene, linear low density polyethylene, ethylene-methyl acrylate, ethylene-ethyl acrylate, ethylene butyl acrylate, or blends thereof; and wherein the sealing layer has a thickness of 1 to 200 microns.
4. The multilayer film according to claim 1, wherein the alcohol barrier layer substantially prevents alcohol from passing through the multilayer film.
5. The multilayer film according to claim 1, wherein the alcohol barrier layer has a thickness of 1 to 100 microns.
6. The multilayer film according to claim 1, further comprising a tie layer that is positioned between the barrier layer and the alcohol barrier layer; wherein the tie layer comprises maleic anhydride grafted polyethylene; a copolymer of ethylene; maleic anhydride grafted linear low-density polyethylene; or blends thereof; and wherein the tie layer has a thickness of 1 to 100 microns.
7. The multilayer film according to claim 1, wherein the multilayer film is formed as a tube, with the barrier layer forming an outer layer of the tube and the sealing layer forming an inner layer of the tube.
8. The multilayer film according to claim 1, wherein the multilayer film is produced by blown film extrusion.
9. The multilayer film according claim 1, wherein the multilayer film forms a pouch that contains alcohol.
10. The multilayer film according to claim 9, wherein the pouch is a fluid reservoir for a fluid dispenser and contains an alcohol-based hand cleaning fluid, the hand cleaning fluid comprising 70% to 100% alcohol.
11. The multilayer film according to claim 9, wherein the barrier layer forms an outer layer of the pouch and the sealing layer forms an inner layer of the pouch; and wherein the pouch is sealed by heating the multilayer film so that the sealing layer of a first portion of the pouch melts to form a seal with the sealing layer of a second portion of the pouch, without melting the barrier layer.
12. The multilayer film according to claim 1, wherein the multilayer film is transparent, flexible, and has a thickness of 110 to 160 microns.
13. The multilayer film according to claim 1, wherein the barrier layer comprises low density polyethylene, medium density polyethylene, high density polyethylene, a polyolefin plastomer, a polyolefin elastomer, cyclic olefin copolymer, or blends thereof; and wherein the barrier layer has a higher melting temperature than the sealing layer.
14. The multilayer film according to claim 1, wherein the barrier layer comprises nylon 6 or polyethylene terephthalate; and wherein the sealing layer comprises low density polyethylene.
15. A multilayer film comprising: a barrier layer; a sealing layer; and an alcohol barrier layer; wherein the alcohol barrier layer is positioned between the barrier layer and the sealing layer; wherein the alcohol barrier layer comprises a cyclic olefin copolymer; wherein the barrier layer comprises nylon 6 or polyethylene terephthalate; wherein the sealing layer comprises low density polyethylene; wherein the multilayer film further comprises a tear resistance layer that is positioned between the barrier layer and the alcohol barrier layer; and wherein the tear resistance layer comprises low density polyethylene.
16. A multilayer film comprising: a barrier layer; a sealing layer; and an alcohol barrier layer; wherein the alcohol barrier layer is positioned between the barrier layer and the sealing layer; wherein the alcohol barrier layer comprises a cyclic olefin copolymer; wherein the barrier layer has a higher melting temperature than the sealing layer; wherein the multilayer film further comprises a tear resistance layer that is positioned between the barrier layer and the alcohol barrier layer; wherein the tear resistance layer comprises low density polyethylene; wherein the barrier layer comprises a blend of high density polyethylene and low density polyethylene, or a blend of high density polyethylene, cyclic olefin copolymer, and low density polyethylene; and wherein the sealing layer comprises low density polyethylene.
17. The multilayer film according to claim 15, wherein the barrier layer has a higher melting temperature than the sealing layer; wherein the barrier layer has a thickness of 5 to 20 microns; wherein the sealing layer has a thickness of 1 to 200 microns; wherein the alcohol barrier layer substantially prevents alcohol from passing through the multilayer film; wherein the alcohol barrier layer has a thickness of 1 to 100 microns; wherein the multilayer film is produced by blown film extrusion; and wherein the multilayer film is transparent, flexible, and has a thickness of 110 to 160 microns.
18. The multilayer film according to claim 17, wherein the multilayer film forms a pouch that contains alcohol; and wherein the pouch is a fluid reservoir for a fluid dispenser and contains an alcohol-based hand cleaning fluid, the hand cleaning fluid comprising 70% to 100% alcohol.
19. The multilayer film according to claim 16, wherein the barrier layer has a thickness of 5 to 20 microns; wherein the sealing layer has a thickness of 1 to 200 microns; wherein the alcohol barrier layer substantially prevents alcohol from passing through the multilayer film; wherein the alcohol barrier layer has a thickness of 1 to 100 microns; wherein the multilayer film is produced by blown film extrusion; and wherein the multilayer film is transparent, flexible, and has a thickness of 110 to 160 microns.
20. The multilayer film according to claim 19, wherein the multilayer film forms a pouch that contains alcohol; and wherein the pouch is a fluid reservoir for a fluid dispenser and contains an alcohol-based hand cleaning fluid, the hand cleaning fluid comprising 70% to 100% alcohol.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Further aspects and advantages of the invention will appear from the following description taken together with the accompanying drawings, in which:
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DETAILED DESCRIPTION OF THE DRAWINGS
(21)
(22) As shown in
(23) The barrier layer 14 is formed from polyamide, and has a thickness of about 10 to 20 microns. The alcohol barrier layer 16 is formed from cyclic olefin copolymer, and has a thickness of about 20 microns. The sealing layer 18 is formed from polyethylene, and has a thickness of about 80 microns.
(24) The film 10 is thin, transparent, and flexible, and can be used to produce products such as the gusseted pouch 20 shown in
(25) The sealing layer 18 has a relatively low melting temperature of between 105 degrees Celsius and 115 degrees Celsius, which allows the sealing layer 18 to be melted to, for example, produce heat sealed top 22 and bottom 24 edges of the pouch 20 shown in
(26) The barrier layer 14 has a higher melting point than the sealing layer 18, preferably above 150 degrees Celsius. In some embodiments, the melting temperature of the barrier layer 14 is 220 degrees Celsius or more. This higher melting temperature allows heat to be applied to the film 10 via the barrier layer 14, such as by the heat sealing device 26, so as to melt the sealing layer 18 without also melting the barrier layer 14. The barrier layer 14 and the film 10 itself is thus prevented from adhering to the heat sealing device 26. The barrier layer 14 is also puncture resistant, which further enhances the film's 10 usefulness as packaging for liquid materials, such as alcohol and alcohol based solutions, which would leak out of even minute holes in the film 10. The melting temperature of the barrier layer 14 is preferably at least about 20 to 80 degrees Celsius above the melting temperature of the sealing layer 18.
(27) The alcohol barrier layer 16 also preferably has a higher melting temperature than the sealing layer 18. This helps to keep the alcohol barrier layer 16 intact, with a uniform thickness, in the area where the film 10 is heat sealed, thereby maintaining the desired alcohol barrier properties of the film 10 in the heat sealed area.
(28) The layers 14, 16, 18 of the film 10 are preferably selected to adhere to each other, and to remain bonded under a wide range of conditions. For example, the layers 14, 16, 18 are preferably selected to remain bonded when the film 10 is heated, such as during heat sealing. The layers 14, 16, 18 are also preferably selected to remain bonded together when the film 10 is exposed to concentrated alcohol for extended periods of time.
(29) The process by which the pouch 20 is produced from the film 10 will now be described with reference to
(30) The open bottom end 32 of the cut section 28 of tube 12 is then placed in a heat sealing device 26, as shown in
(31) To heat seal the bottom end 32 of the cut section 28 of tube 12, the heated sealing bar 40 is pressed downwardly onto the bottom end 32 of the cut section 28, with the bottom end 32 positioned between the heated strip 42 of the base portion 38 and the heated strip 44 of the sealing bar 40. The heat from the heated strips 42, 44 is transferred by conduction into the sealing layer 18 through the barrier layer 14 and the alcohol barrier layer 16. Since the temperature is above the melting temperature of the sealing layer 18, this causes the sealing layer 16 to melt. When the cut section 28 of tube 12 is flattened by the downwards pressure of the sealing bar 40, the sealing layer 16 on a front portion 46 of the cut section 28 is moved into contact with the sealing layer 16 on a back portion 48 of the cut section 28. The heat from the heat sealing device 26 causes the sealing layer 16 on the front portion 46 of the cut section 28 to melt and adhere to the sealing layer 16 on the back portion 48, forming the heat sealed bottom edge 24 as shown in
(32) In addition to the cut section 28 of film 10, the finished pouch 20 also includes a spout 50, which is best shown in
(33) The sealing portion 56 of the spout body 52 has two tapered sealing surfaces 60, 62 that each carry a number of horizontal polyethylene ridges 64. A guide collar 66 extends outwardly from the spout body 52 immediately below the sealing portion 56.
(34) To assemble the pouch 20, the sealing portion 56 of the spout body 52 is placed into the open top end 30 of the cut section 28 of film 10. The guide collar 66 remains outside of the open top end 30, and helps to position the sealing portion 56 in place. The top end 30 of the cut section 28 is then heat sealed to produce the heat sealed top edge 22, as shown in
(35) As shown in
(36) The pouch 20 can be used to store alcohol or products containing alcohol, preferably in ranges in excess of 40%, or more preferably 70% to 95% or more, such as a concentrated alcohol-based hand sanitizer 72 containing ethanol or isopropanol. The hand sanitizer 72 is stored within the internal chamber 70 of the pouch 20. To fill the internal chamber 70, the hand sanitizer 72 can be delivered through the spout 50 by a filling device, not shown. Once full, the outlet opening 74 of the spout 50 is preferably sealed to prevent the hand sanitizer 72 from leaking out of the pouch 20, such as with a sealing cap, not shown. The filled pouch 20 can then be placed in storage or transported to another facility or location where the hand sanitizer 72 is needed.
(37) The alcohol barrier layer 16 in the film 10 helps to prevent the alcohol contained in the hand sanitizer 72 from evaporating or otherwise leaking out of the pouch 20. The spout body 52, which is formed from relatively thick polyethylene having a thickness of about 1 mm, also helps to prevent the alcohol from evaporating. In particular, the thickness of the polyethylene acts as a barrier that prevents the alcohol from passing through the spout body 52, despite the absence of cyclic olefin copolymer in this part of the pouch 20.
(38) As best seen in
(39) In other embodiments, the spout 50 may optionally incorporate a layer or a blend of cyclic olefin copolymer, to increase the alcohol barrier properties thereof. The top and bottom edges 22, 24 may also incorporate additional cyclic olefin copolymer, such as by applying a layer of cyclic olefin copolymer to the bottom surface 96 of the bottom edge 24.
(40) The pouch 20 can be used as a reservoir 76 for hand sanitizer 72 to be dispensed from a hand sanitizer dispenser 78, such as the dispenser 78 shown in
(41) The flexible nature of the film 10 allows the pouch 20 to collapse as the hand sanitizer 72 is dispensed therefrom. This allows the internal chamber 70 to remain airless, since the dispensed hand sanitizer 72 does not need to be replaced by air as it would in a rigid container. The cyclic olefin copolymer in the alcohol barrier layer 16 furthermore prevents the alcohol contained in the hand sanitizer 72 from evaporating or otherwise leaking out from the pouch 20 while the pouch 20 is held within the housing 80 of the dispenser 78. The hand sanitizer 72 is thus able to maintain a high alcohol concentration until it is dispensed.
(42) Reference is now made to
(43) The pouch 20 is formed from the multilayer film 10 shown in
(44) The fluid pump 100 is similar to the pumps described in U.S. Pat. No. 9,175,674 to Ophardt et al., issued Nov. 3, 2015, U.S. Pat. No. 8,365,954 to Ophardt et al, issued Feb. 5, 2013, U.S. Pat. No. 9,437,103 to Ophardt, issued Sep. 6, 2016, US 2008/0121664 to Ophardt et al., published May 29, 2008, U.S. Pat. No. 7,765,918 to Ophardt et al., issued Aug. 3, 2010, U.S. Pat. No. 7,798,369 to Ophardt, issued Sep. 21, 2010, US 2008/0112830 to Ophardt et al., published May 15, 2008, and U.S. Pat. No. 8,074,844 to Ophardt et al., issued Dec. 13, 2011, each of which is incorporated herein by reference.
(45) As best seen in
(46) The inlet tube 126 extends axially downwards from the piston chamber forming body 114 to a fluid inlet 106. A one-way fluid inlet valve 118 is interposed between the inlet tube 126 and the piston chamber 116, and prevents fluid from passing from the piston chamber 116 into the inlet tube 126, while permitting fluid to pass from the inlet tube 126 into the piston chamber 116.
(47) The elongated spout 102 extends laterally from the piston forming body 112 to a fluid outlet 104. The spout 102 extends horizontally for most of its length, with a slight downwards curve adjacent to the fluid outlet 104. A one-way fluid outlet valve 120 is interposed between the spout 102 and the piston chamber 116, and prevents fluid from passing from the spout 102 into the piston chamber 116, while permitting fluid to pass from the piston chamber 116 into the spout 102. The one-way fluid inlet valve 118 and the one-way fluid outlet valve 120 are shown in
(48) As best seen in
(49) As in the first embodiment, the pouch 20 can be used as a reservoir 76 for a hand sanitizer dispenser 78. The fluid pump 100 is adapted for use with the dispenser 78 shown in
(50) The pouch 20 is configured to sit within the housing 80 of the dispenser 78, with the fluid outlet 104 accessible at the front of the dispenser 78. An actuation bar 124 is operatively connected to the fluid pump 100 for activating the pump 100 and dispensing the hand sanitizer 72 from the pouch 20. When the actuation bar 124 is depressed, the piston forming body 112 is moved axially downwards relative to the piston chamber forming body 114, thereby reducing the volume of the piston chamber 116. This pressurizes hand sanitizer 72 contained in the piston chamber 116, causing the hand sanitizer 72 to move past the one-way fluid outlet valve 120 and through the spout 102 to be dispensed from the fluid outlet 104. The dispensed hand sanitizer 72 can be received, for example, by a user's hand positioned below the fluid outlet 104.
(51) When the actuation bar 124 is released, the dispenser 78 is configured to move the piston forming body 112 axially upwards relative to the piston chamber forming body 114, for example under the biasing force of a spring, not shown. This increases the volume of the piston chamber 116, creating a vacuum that draws hand sanitizer 72 from the pouch 20 past the one-way inlet valve 118 and into the piston chamber 116. The piston chamber 116 is thus primed for further dispensing of hand sanitizer 72 upon activation of the actuation bar 124. The fluid pump 100 typically needs to be primed when first installed in the dispenser 78 by depressing and releasing the actuation bar 124 one or more times, to fill the piston chamber 116 with hand sanitizer 72 and remove any air contained therein.
(52) As in the first embodiment, the flexible nature of the film 10 allows the pouch 20 to collapse as the hand sanitizer 72 is dispensed therefrom. This allows the internal chamber 70 to remain airless. Optionally, the capillary bar 108 is inserted into the pouch 20 to maintain an open pathway into the fluid inlet 106 as the pouch 20 collapses. In particular, the capillary bar 108 prevents the film 10 from covering and potentially sealing the fluid inlet 106 as the pouch 20 collapses. The ridges also help prevent the film 10 from forming a fluid tight seal against the capillary bar 108. The bar 108 thus holds the two sides of the pouch 20 apart along a region of the pouch 20 extending from the fluid inlet 106 towards the bottom edge 24, and provides a pathway for drawing hand sanitizer 72 into the fluid inlet 106 as the pouch 20 collapses. The effectiveness of the fluid pump 100 in drawing fluid from the pouch 20 is thereby improved, particularly for fluids with a higher viscosity.
(53) Reference is now made to
(54) The film 10 is produced by blown film coextrusion, as in the first embodiment, and can be used in exactly the same manner as in the first and second embodiments. For example, the film 10 can be used to produce the pouch 20 shown in
(55) In the third embodiment of the invention shown in
(56)
(57) As in the previously described embodiments, the film 10 is produced by blown film coextrusion, and can be used in exactly the same manner as in the previous embodiments. The film 10 can, for example, be used to produce the pouch 20 shown in
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(60) The film 10 shown in
(61) Optionally, in the embodiment shown in
(62) Although six specific exemplary embodiments of the invention have been illustrated and described, the invention is not limited to these specific embodiments. For example, the film 10 may include additional layers beyond those described above to provide additional functionality. Nor is it necessary for the film 10 to be extruded as a tube 12. The film 10 could instead be extruded as a flat sheet, which is then folded and/or heat sealed to form a reservoir 76 or other structure. In some embodiments of the invention, the film 10 can be produced by methods other than blown film extrusion, such as by lamination or coating.
(63) The barrier layer 14 is not limited to the specific composition and thickness described in the embodiments. Rather, the barrier layer 14 could have any suitable composition and thickness, and may comprise, for example, polyamide, copolyamide, polyester, polypropylene, nylon 6, nylon 66, PET, high density polyethylene, low density polyethylene, cyclic olefin copolymer, or blends thereof. In some embodiments, the barrier layer 14 has a thickness in the range of 1 to 100 microns, in the range of 1 to 10 microns, in the range of 10 to 20 microns, in the range of 5 to 10 microns, in the range of 2 to 10 microns, or about 10 microns. The barrier layer 14 is preferably selected to provide puncture resistance and/or to have a relatively high melting temperature relative to the sealing layer 18.
(64) The alcohol barrier layer 16 is also not limited to the specific composition and thickness described in the embodiments. Rather, any suitable composition and thickness incorporating a sufficient quantity of cyclic olefin copolymer to substantially prevent the movement of alcohol through the film 10 could be used. For example, in some embodiments the alcohol barrier layer 16 is 100% cyclic olefin copolymer, while in others it is a cyclic olefin copolymer blend. In some embodiments the alcohol barrier layer 16 has a thickness in the range of 1 to 100 microns, in the range of 5 to 20 microns, in the range of 10 to 20 microns, in the range of 2 to 20 microns, or about 20 microns. Manufacturers of cyclic olefin copolymer include TOPAS Advanced Polymers (trademark: TOPAS), MITSUI CHEMICALS (trademark: APEL), JSR Corporation (trademark: ARTON), and ZEON Corporation (trademarks: ZEONEX and ZEONOR). In some embodiments, the alcohol barrier layer 16 is formed from TOPAS 8007. The alcohol barrier layer 16 is preferably selected to provide the desired rate of alcohol loss and the desired flexibility of the film 10.
(65) The sealing layer 18 is also not limited to the specific composition and thickness described in the embodiments. Rather, any suitable composition and thickness could be used. The sealing layer 18 may comprise, for example, polyethylene, a copolymer of ethylene, polypropylene, a copolymer of propylene, a polyolefine elastomer, a polyolefine plastomer, ethylene-vinyl acetate, low-density polyethylene, linear low-density polyethylene, or blends thereof. In some embodiments, the sealing layer 18 has a thickness in the range of 1 to 200 microns, in the range of 60 to 100 microns, in the range of 20 to 100 microns, or about 80 microns. The sealing layer 18 is preferably selected to have a melting temperature that is significantly lower than the melting temperature of the barrier layer 14, and to have a sufficient thickness to provide a robust seal when heat sealed.
(66) The tie layer 82 also need not have the specific composition and thickness described in the embodiments. For example, the tie layer 82 may comprise maleic anhydride grafted polyethylene, a copolymer of ethylene, maleic anhydride grafted linear low-density polyethylene, or blends thereof. In some embodiments, the tie layer 82 has a thickness in the range of 1 to 100 microns, in the range of 10 to 20 microns, in the range of 2 to 20 microns, about 10 microns, or about 20 microns. The tie layer 82 is preferably selected to provide a strong bond between the barrier layer 14 and the alcohol barrier layer 16, even when exposed to concentrated alcohol for an extended period of time.
(67) The second alcohol barrier layer 84 also does not need to have the specific composition and thickness described in the embodiments. In some embodiments, the second alcohol barrier layer 84 has a thickness in the range of 1 to 50 microns, in the range of 1 to 10 microns, or about 5 microns. The second alcohol barrier layer 84 is preferably selected to help prevent alcohol from passing through the film 10. In some embodiments, the second alcohol barrier layer 84 is selected to reduce the amount of alcohol that diffuses through the film 10 to prevent or reduce the delamination and/or degradation of one or more layers of the film 10.
(68) The overall thickness 86 of the film 10 is, in some embodiments, in the range of 80 to 150 microns, or in the range of 110 to 160 microns. In other embodiments, the thickness 86 of the film 10 may be larger or smaller. The thickness 86 may be adjusted to suit the intended purpose of the film 10 and/or its desired properties. Preferably, the thickness 86 is selected to maintain flexibility and reduce costs, while also providing the desired functionality, including the desired protection against the loss of alcohol through the film 10. In some embodiments, the film 10 is selected to have a smaller thickness 86 in order to improve the transparency of the film 10.
(69) The layers may also have different melting temperatures than the exemplary melting temperatures described above. In embodiments of the invention that use heat sealing, the barrier layer 14 should have a higher melting temperature than the sealing layer 18, but the absolute values of the melting temperatures can vary depending on the composition and intended use of the film 10. For example, in some embodiments where the film 10 is exposed to very high temperatures during heat sealing, the barrier layer 14 preferably has a very high melting temperature. In other embodiments where the heat sealing is done at a lower temperature, it may be preferable for the barrier layer 14 to have a lower melting temperature, particularly if this allows for other desired properties such as increased flexibility, increased puncture resistance, and/or reduced costs. The alcohol barrier layer 16 also preferably has a higher melting temperature than the sealing layer 18.
(70) The composition and thickness of the layers 14, 16, 18, 82, 84 may be selected based on the desired properties of the film 10. For example, the tie layer 82 is preferably selected to maintain strong adhesion between the layers 14, 16, 18, 82, 84, even when exposed to concentrated alcohol for an extended period of time. The thickness and composition of the alcohol barrier layer 16 can also be adjusted to alter the alcohol barrier properties, flexibility, and other characteristics of the film 10. In some preferred embodiments, the film 10 is configured so that less than 1% by weight of the alcohol is lost by evaporation from the pouch 20 after 3 years. In other embodiments, the film 10 may be configured to be more or less effective as an alcohol barrier. For example, in embodiments where the pouch 20 is intended to carry alcohol for a shorter time period, or at a lower concentration, the film 10 may be configured to permit alcohol to escape at a faster rate, such as by reducing the amount of cyclic olefin copolymer. A person skilled in the art could, through routine testing, adjust the composition of the film 10 so as to arrive at the desired properties, including the rate of alcohol loss through the film 10. In some embodiments, the pouch 20 is configured so that less than 5% by weight of the alcohol is lost by evaporation through the film 10 after 6 months at 40 degrees Celsius and at 70% relative humidity, for example under lab conditions intended to test a 3 year shelf-time. The pouch 20 may also be configured so that less than 5% by weight of the alcohol is lost by evaporation through the film 10 after 3 years at room temperature, 20 degrees Celsius, and at 45-60% relative humidity.
(71) The layers 14, 16, 18, 82, 84 are preferably selected to remain intact and adhered to each other under a wide range of conditions. For example, the layers 14, 16, 18, 82, 84 are preferably selected to remain bonded when exposed to concentrated alcohol for an extended period of time, and under a wide range of temperatures, humidity levels, and physical stresses. Testing of some preferred embodiments has found that the pouch 20 is able to contain 70% alcohol for 4 weeks at 40 degrees Celsius and at 70% relative humidity without delamination or blistering. In other embodiments, the film 10 may be configured to remain bonded together for a different time period under different conditions, such as a different temperature, relative humidity, alcohol concentration, and duration. A person skilled in the art could, through routine testing, adjust the composition of the film 10 so as to arrive at the desired properties. For example, in some embodiments the composition of one or more of the layers 14, 16, 18, 82, 84 could be selected to reduce costs, though the resulting film 10 is more prone to delamination when exposed to concentrated alcohol for an extended period of time. This may be preferred, for example, in embodiments where the pouch 20 is used to contain alcohol at a low concentration or for a short period of time.
(72) In some preferred embodiments, the film 10 remains transparent and does not experience discoloration when exposed to concentrated alcohol for an extended period of time. For example, testing of some preferred embodiments has found that the pouch 20 is able to contain 70% alcohol for 4 weeks at 40 degrees Celsius and at 70% relative humidity without discoloration. Other embodiments of the invention may be more or less prone to discoloration. A person skilled in the art could, through routine testing, adjust the composition of the film 10 so as to arrive at the desired properties, including the rate of discoloration under various conditions.
(73) The layers 14, 16, 18, 82, 84 may also be selected to have more than one function. For example, in some embodiments of the invention the alcohol barrier layer 16 also serves as a tie layer 82, providing a strong bond between the barrier layer 14 and the sealing layer 18. The alcohol barrier layer 16 may, for example, be formed from a blend of cyclic olefin copolymer and another material with suitable adhesive properties, such as maleic anhydride grafted polyolefin, polyethylene, polypropylene, their copolymers, or blends thereof. In some embodiments, the alcohol barrier layer 16 is formed from a blend of cyclic olefin copolymer:maleic anhydride grafted polyolefin at a ratio of 80:20 or 70:30, or any other suitable ratio selected to provide the desired properties.
(74) The pouch 20 is not limited to use as a reservoir 76 for a hand sanitizer dispenser 78 as has been described in the examples. Rather, the pouch 20 could be used to contain alcohol-based products for any suitable purpose, including other hygiene, pharmaceutical, or medical applications. For example, the pouch 20 could be used to store an alcohol-based product for sterilizing medical equipment. The pouch 20 is not limited to the specific construction, shape, and dimensions as depicted in the drawings. Rather, any construction suitable for the pouch's 20 intended purpose could be used. The film 10 is also not limited to being used to produce a pouch 20. Rather, the film 10 could be used for any suitable purpose, including for forming an alcohol evaporation barrier on other containers or products.
(75) The pouch 20 may be used to contain any suitable product, including any liquid, gel, or emulsion containing a high or a low concentration of alcohol. The pouch 20 may contain, for example, products with an alcohol concentration of greater than 20%, greater than 40%, greater than 60%, greater than 70%, greater than 80%, or in the range of 20% to 95%, in the range of 40% to 100%, in the range of 70% to 100%, in the range of 70% to 95%, in the range of 80% to 90%, about 85%, or about 70%. In some embodiments, the pouch 20 contains up to 80% ethanol or isopropanol.
(76) The spout 50 is not limited to the construction described and illustrated in the exemplary embodiments, but rather could have any suitable construction that permits the hand sanitizer 72, or other product, to be dispensed from the pouch 20. In some embodiments, the pouch 20 may have no spout 50 at all. For example, in some embodiments the hand sanitizer 72 could be accessed by puncturing or tearing the film 10, rather than via a spout 50. The spout 50 could also incorporate a valve structure, not shown, to control the movement of fluid between the inlet opening 58 and the outlet opening 74. Any suitable valve structure known to a person skilled in the art could be used.
(77) Any suitable device and/or method for filling the pouch 20 with the hand sanitizer 72, or other product, could be used. Preferably, the device and/or method is selected to remove all air from the internal chamber 70 during the filling operation, so that there is no air within the internal chamber 70 during storage, during transportation, and/or during use of the pouch 20. Preferably, the pouch 20 is also configured to prevent air from entering the internal chamber 70. This may be achieved by placing a barrier over the outlet opening 74, such as a cap or a heat sealed section of the film 10; by providing a valve structure within the spout 50 that prevents air from entering the internal chamber; or by any other method known to a person skilled in the art.
(78) In embodiments of the invention where the pouch 20 is used as a reservoir for a dispenser 78, either the pouch 20 or the dispenser 78 should include a dispensing mechanism for dispensing the hand sanitizer 72, or other product, from the pouch 20. The dispensing mechanism is preferably configured to prevent air from entering the pouch 20 during the dispensing operation. The dispensing mechanism may be configured to break a seal and/or displace a cap from the pouch 20 to access the hand sanitizer 72. The dispensing mechanism may, for example, incorporate a mechanism for displacing a seal or a capping member as described in European Patent No. 2644280 to Ophardt et al., granted Dec. 13, 2017, which is incorporated herein by reference. The dispensing mechanism is preferably configured to prevent evaporation of alcohol from the hand sanitizer 72 through the dispensing mechanism, such as by being formed from a thick, air tight plastic.
(79) Any suitable dispensing mechanism as would be known to a person skilled in the art could be used. For example, the dispenser 78 may incorporate one or more pump mechanism as described in U.S. Pat. No. 8,816,860 to Ophardt et al., issued Aug. 26, 2014; U.S. Pat. No. 5,373,970 to Ophardt, issued Dec. 20, 1994; U.S. Pat. No. 8,976,031 to Ophardt, issued Mar. 10, 2015; U.S. Patent Application Publication No. 2016/0097386 to Ophardt et al., published Apr. 7, 2016; U.S. Patent Application Publication No. 2016/0256015 to Ophardt et al., published Sep. 8, 2016; U.S. Pat. No. 7,984,825 to Ophardt et al., issued Jul. 26, 2011; U.S. Pat. No. 8,684,236 to Ophardt, issued Apr. 1, 2014; U.S. Pat. No. 5,836,482 to Ophardt et al., issued Nov. 17, 1998; U.S. Pat. No. 8,113,388 to Ophardt et al., issued Feb. 14, 2012; and U.S. Patent Application Publication No. 2015/0190827 to Ophardt et al., published Jul. 9, 2015, each of which is incorporated herein by reference.
(80) The invention includes all methods and uses of the film 10 and pouch 20, whether explicitly described herein or implicit in the described structures and features. For example, the invention includes a method of producing a pouch 20, including the steps of extruding a tube 12 of the multilayer film 10, cutting the tube 12 transversely at spaced intervals, and heat sealing the tube transversely to form the pouch 20. The invention also includes a method of storing alcohol in a pouch 20 comprising the multilayer film 10, including the steps of extruding a tube 12 of the multilayer film 10, cutting the tube 12 transversely at spaced intervals, heat sealing the tube transversely to form the pouch 20, and filling the pouch 20 with alcohol, such as ethanol.
(81) The invention is not limited to the specific exemplary methods and uses that have been described, including the described order of steps. For example, in some embodiments of the invention the tube 12 could be heat sealed before being cut transversely. The pouch 20 could also be filled before it is heat sealed and/or cut in some embodiments. Nor is the invention limited to the specific manner of filling the pouch 20 that has been described. Rather, any suitable method of filling the pouch 20 that would occur to a person skilled in the art could be used. The invention is also not limited to the specific exemplary dispenser 78, spout 50, and heat sealing device 26 described and illustrated in the drawings. The invention also does not necessarily use heat to seal the pouch 20. In some embodiments, alternative sealing methods such as ultrasonic welding may be used instead. Testing has shown that, in some embodiments, ultrasonic welding may provide higher sealing efficiency and strength, in particular at the welding surface of the spout 50, which is a critical area during manufacturing to avoid leakage from the pouch 20.
(82) In some preferred embodiments, the alcohol barrier layer 16 is positioned between two polyethylene layers, and is preferably extruded between the two polyethylene layers. For example, optionally the barrier layer 14 and the sealing layer 18 are formed from polyethylene, and the alcohol barrier layer 16 is positioned directly between the barrier layer 14 and the sealing layer 18 to form a structure as follows: barrier layer 14/alcohol barrier layer 16/sealing layer 18. Alternatively, one or more of the two polyethylene layers on either side of the alcohol barrier layer 16 could correspond to an additional layer other than the barrier layer 14 and/or the sealing layer 18. For example, the barrier layer 14 could be formed from polyamide, and the film 10 could have a structure as follows: polyamide barrier layer 14/tie layer 82/polyethylene layer/cyclic olefin copolymer alcohol barrier layer 16/polyethylene sealing layer 18. Alternatively, the film 10 could have the following structure: polyamide barrier layer 14/ethylene vinyl alcohol layer/tie layer 82/polyethylene layer/cyclic olefin copolymer alcohol barrier layer 16/polyethylene sealing layer 18. The film 10 could also have a structure as follows, for example: polyethylene barrier layer 14/tie layer 82/ethylene vinyl alcohol layer/tie layer 82/polyethylene layer/cyclic olefin copolymer alcohol barrier layer 16/polyethylene sealing layer 18.
(83) In some preferred embodiments, the melting temperature of the barrier layer 14 is above 100 degrees Celsius, and the barrier layer 14 is formed from or includes polyethylene. The barrier layer 14 may, for example, include low density polyethylene, medium density polyethylene, high density polyethylene, polyolefin plastomers, polyolefin elastomers, or blends thereof. The film 10 may, for example, have a structure as follows: first polyethylene barrier layer 14/cyclic olefin copolymer alcohol barrier layer 16/second polyethylene sealing layer 18, where the first polyethylene barrier layer 14 is selected to have a higher melting temperature or glass temperature than the second polyethylene sealing layer 18.
(84) In other preferred embodiments, the glass transition temperature of the barrier layer 14 is above 50 degrees Celsius, and the barrier layer 14 is formed from or includes cyclic olefin copolymer or blends thereof. For example, the film 10 could have a structure as follows: cyclic olefin copolymer barrier layer 14/cyclic olefin copolymer alcohol barrier layer 16/polyethylene sealing layer 18, where the cyclic olefin copolymer barrier layer 14 is selected to have a higher melting temperature or glass temperature than the polyethylene sealing layer 18. In other embodiments, the functions of the barrier layer 14 and the alcohol barrier layer 16 could be combined in one layer, with the film for example having a structure as follows: cyclic olefin copolymer/polyethylene, where the cyclic olefin copolymer has a higher melting temperature or glass temperature than the polyethylene.
(85) In some embodiments, the sealing layer 18 is formed from or includes a copolymer of ethylene. The copolymer of ethylene may, for example, include ethylene-methyl acrylate, ethylene-ethyl acrylate, or ethylene butyl acrylate.
(86) Although this disclosure has described and illustrated certain preferred embodiments of the invention, it is to be understood that the invention is not restricted to these particular embodiments. Rather, the invention includes all embodiments which are functional, chemical or mechanical equivalents of the specific embodiments and features that have been described and illustrated herein.