AU2020204052B2 - Thermoplastic Liner - Google Patents

Abstract

- 13 A thermoplastic liner for use as a moisture barrier comprises a hollow tubular body made from a woven thermoplastic comprising material configured to substantially block the ingress of moisture; and an opening at one end of the hollow tubular body for intake into the hollow of the hollow tubular body. In one aspect a closed opposite end forms a base configured to substantially block the ingress of moisture external to the hollow tubular body. - - 13 - - Abstract2020 2020204052 17 Jun 1/2 Figure 1 Figure 2 10 16 14 12 18 20 22 26 24 18 10 16 12 14 26 24 20 20 20 40 52 1 7 Ju n 20 20 20 20 20 40 52 1 7 Ju n 20 20 1/2 10 16 14 2020204052 26 24 18 10 14 12 26 24 22 18 20

Description

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2020 Thermoplastic Liner

2020204052 17 Jun of the Field of Field Invention the Invention

[1] The present invention relates to a thermoplastic liner, including but not limited to a liner for for use as aa moisture use as barrier. moisturebarrier.

Background

[2] Polymer liners are known to be used in the packaging industry for protecting moisture sensitive materials, such as washing powders, cements and rice. The liners are used as moisture barriers to prevent or block the ingress of moisture external to the liner from interacting with their contents.

[3] The polymer liners are typically in the form of a woven tube. The tube is fabricated by first forming a parent material by weaving thin polymer strands in the vertical and horizontal weave planes, and laminating a thin polymer laminate either as an inner material and/or the outer material. Typically, the polymer strands are polypropylene and the polymer laminate are polyethylene / Biaxial oriented polypropylene (BOPP). It is generally recognised by industry that liners need to be sealed at the base to prevent any water ingress. As such, the openings of the tube are typically closed by the use of stitching or adhesives. However, these methods do not produce a water tight seal and would not enable the polymer liner to be suitable for submergence in water.

[4] In specialist applications wherein the liner is exposed to high levels of moisture, for example a blast hole liner, it is necessary to use another method of closing the tube. In some cases, the tube is tied closed sometimes with waste material therein to form a weight. Welding the opening of the polymer liner closed is an alternate method for producing a water tight seal. However, with welding the polymer liner, a number of disadvantages are produced which makes the method unviable for use. At the welding area, the joint will have very little mechanical strength as the polymer laminate is extremely thin and the parent woven material may not bond sufficiently to the laminate, due to the differences in polymer groups and the differences in melting points.

[5] Any references to documents that are made in this specification are not intended to be an admission that the information contained in those documents form part of the common general knowledge known to a person skilled in the field of the invention, unless explicitly stated as stated assuch. such.

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Summary of the Invention

[6] According to a first aspect of the invention, there is provided a thermoplastic liner for use as a moisture barrier, comprising: a hollow tubular body made from a woven thermoplastic material configured to substantially 2020204052 17 block the ingress of moisture; an opening at one end of the hollow tubular body for intake into the hollow of the hollow tubular body;and a closed opposite end to form a base configured to substantially block the ingress of moisture external to the hollow tubular body; wherein the woven thermoplastic material is comprised of a parent material and at least one laminate material; and wherein the parent material is comprised of polymer components; and the polymer components are configured as a plurality of strands in the vertical direction comprising at least one type of polyethylene or polypropylene or a blend thereof, and as a plurality of strands in the horizontal direction comprising at least one type of polyethylene or polypropylene or a blend thereof.

[7] In a preferred embodiment of the invention, the polymer components of the parent material comprise one or more types of polyethylene or polypropylene or a blend thereof. In an embodiment an embodiment the the horizontal horizontal strands strands aresame are the the as same as the vertical the vertical strands. strands.

[8] In an embodiment of the invention, the type of polyethylene in the vertical direction is the same as the type of polyethylene in the horizontal direction. Types of polyethylene that may comprise the polymer components may be selected or blended from the group comprising: High-Density Polyethylene, Low-Density Polyethylene, Linear Low-Density Polyethylene, Ultrahigh Molecular Weight Polyethylene, Medium-Density Polyethylene, High molecular-weight polyethylene, Ultra-low-molecular-weight polyethylene, High-density cross linked polyethylene, Chlorinated polyethylene, Cross-linked polyethylene, and Very-low density polyethylene, amongst other types of polyethylene.

[9] In an embodiment of the invention, the type of polypropylene in the vertical direction is the same as the type of polypropylene in the horizontal direction. Types of polypropylene that may comprise the polymer components may be selected or blended from the group comprising: High-Density Polypropylene, Low-Density Polypropylene, Linear Low-Density Polypropylene, Ultrahigh Molecular Weight Polypropylene, Medium-Density Polypropylene, High-molecular-weight polypropylene, Ultra-low-molecular-weight polypropylene, High-density cross-linked polypropylene, Chlorinated polypropylene, Cross-linked polypropylene, and Very 2020204052 17 Jun 2020 low-density polypropylene, amongst other types of polypropylene.

[10] In an embodiment of the invention, the at least one laminate material is configured to be an be an internal internal laminate laminateand/or and/or an an external external laminate. laminate.

[11] In an embodiment of the invention, the at least one laminate material is comprised of the same thermoplastic material as the polymer components of the parent material.

[12] In an embodiment of the invention, the hollow body is configured in a gusseted format.

[13] In an embodiment of the invention, the thermoplastic material comprises electrically conductive additives.

[14] In an embodiment of the invention, the parent material comprises electrically conductive additives.

[15] In an embodiment of the invention, the laminate material comprises electrically conductive additives.

[16] In an embodiment of the invention, the electrically conductive material grounds the thermoplastic liner so as to prevent creation of a static charge.

[17] In an embodiment of the invention, the thermoplastic material comprises electrically conductive thread woven through the thermoplastic material.

[18] In an embodiment of the invention the closed end is welded closed.

[19] According to a second aspect of the invention, there is provided a method of producing a thermoplastic liner for use as a moisture barrier, comprising: manufacturing a woven thermoplastic material configured to substantially block the ingress of moisture; producing a hollow body having at least two openings within the woven thermoplastic material; creating a base on the hollow body by closing one of the at least two openings, preferably by welding; wherein the manufacturing of the woven thermoplastic material is comprised of weaving a 2020204052 17 Jun 2020 plurality of strands running in a vertical direction comprising at least one type of polyethylene or polypropylene or a blend thereof, and a plurality of strands running in a horizontal direction comprising at least one type of polyethylene or polypropylene or a blend thereof to form a parent material; and wherein the manufacturing of the woven thermoplastic material further comprises laminating an internal laminate material and/or an external laminate material to the parent material.

[20] In an embodiment of the method of the invention, the woven thermoplastic material comprises an electrically conductive additive formed in one or more thermoplastics of the thermoplastic material.

[21] In an embodiment of the method of the invention, the thermoplastic material comprises electrically conductive additive formed in one or more thermoplastics of the thermoplastic material. material.

[22] In an embodiment of the method of the invention, the electrically conductive additive comprises a powdered conductor.

[23] In an embodiment of the method of the invention, the electrically conductive additive comprises carbon.

[24] In an embodiment of the method of the invention, the electrically conductive additive comprises an electrically conductive thread/yarn woven through the thermoplastic material.

[25] In an embodiment of the method of the invention, the electrically conductive additive comprises an electrically conductive metallic strip laminated to or woven through the thermoplastic material.

[26] In an embodiment of the method of the invention, the hollow tubular body is configured to comprise a gusset in at least one side of the hollow tubular body such that the hollow tubular body is able to be flattened with the respective gussets formed from folds of the hollow tubular body, such that in the flattened state the tube is more readily stored in a narrow form, but is expandable when the gusset is unfolded.

[27] According to a further aspect of the invention, there is provided a thermoplastic liner for use as a moisture barrier, comprising:

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a hollow tubular body made from a woven thermoplastic material configured to substantially 2020204052 17 Jun 2020

block the ingress of moisture; an opening at one end of the hollow tubular body for intake into the hollow of the hollow tubular body;and an electrically conducting strip running substantially the length of the body; wherein the woven thermoplastic material is comprised of a parent material and at least one laminatematerial. laminate material.

[28] According to a yet further aspect of the invention, there is provided a method of lining a bore hole comprising: providing a thermoplastic liner having a hollow tubular body made from a woven thermoplastic material configured to substantially block the ingress of moisture; an opening at one end of the hollow tubular body for intake into the hollow of the hollow tubular body; and an electrically conducting strip running substantially the length of the body; wherein the woven thermoplastic material is comprised of a parent material and at least one laminate material; and closing an end of the thermoplastic liner; inserting the thermoplastic liner into the bore hole; whereby in use in the event of any electrical charge being generated along the length of the liner, the electrically conducting thread aiding in discharging of the electrical charge.

[29] In an embodiment the end is closed by welding.

[30] In this specification the terms "comprising" or "comprises" are used inclusively and not exclusively or exhaustively.

Brief Description of the Drawings

[31] In order to provide a better understanding, embodiments of the present invention will be described, by way of example only, with reference to the accompanying drawings, in which:

[32] Figure 1 is a perspective view of a thermoplastic liner.

[33] Figure 2 is a perspective view of the thermoplastic liner with an end welded closed.

[34] Figure 3 is a perspective view of the liner in a gusseted format.

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[35] Figure 4 is aperspective view of the thermoplastic liner having conductive material within.

[36] Figure 5 is a perspective view of a thermoplastic liner being inserted into a blast hole, 2020204052 17 with static electricity being created.

[37] Figure 6 is a perspective view of the thermoplastic liner of Figure 4 being inserted into a blast hole, and then grounded by the conductive material of the liner.

Detailed Description

[38] The present invention provides a thermoplastic liner and method for making the same. The liner comprises a woven thermoplastic material configured to substantially block the ingress of moisture, where the woven thermoplastic material is formed into a hollow tubular body. The hollow tubular body has an opening at one end of the hollow tubular body for intake into the hollow of the hollow tubular body. Another opposite end is welded closed to form a base configured to substantially block the ingress of moisture external to the hollow tubular body.

[39] Figure 1 illustrates a thermoplastic liner 10 for use as a moisture barrier according to an initial embodiment of the invention. The liner 10 comprises a woven thermoplastic material 12 configured to substantially block the ingress of moisture through its bulk. The woven material 12 is typically formed as a hollow body 14, typically with a pair of openings 16, 18. In this example, the hollow body 14 is in the shape of a tubular roll, however it would be appreciated by those skilled in the art that the hollow body 14 may be of any suitable shape.

[40] Figure 2 illustrates the thermoplastic liner 10 according to a final embodiment of the invention. The hollow body 14 is made water proof by sealing the opening 18 to form a base 20 configured to substantially block the ingress of moisture into the hollow body 14. The method of sealing the opening 18 is by welding a designated weld area 22, which is located next to the opening 18. This ensures that the base 20 becomes a barrier, created by the weld, between the exterior of the liner 10 and the interior and contents of the liner 10.

[41] The woven material 12 is comprised of a parent material and at least one laminate material. material.

[42] The parent material is formed by the weaving of a plurality of strands running in the vertical direction, known as warp strands 24, with a plurality of strands running in the horizontal direction, known as weft strands 26. That is, the manufacturing of the woven thermoplastic material is comprised of weaving a plurality of strands running in a first direction, through a plurality of strands running in a direction substantially perpendicular to the first direction, to form a parent material. 2020204052 17

[43] The parent material is further comprised of at least one polymer component(s), with one polymer component being associated to the warp strands 24 and the same or another polymer component being associated to the weft strands 26. In this example, the warp strands 24 are made from one of more types of polyethylene, and the weft strands 26 are also made from the same or one or more different types of polyethylene. The main advantages provided by the polyethylene weave include the retention of mechanical strength acquired by the use of polyethylene, which importantly also enables the parent material to strongly bind to the at least one laminate material, whether it is in the form of an internal or external laminate. Various types of polypropylene can be used for the same reasons as above. Further the strands (either or both vertical and horizontal) may be a polyethylene and polypropylene blend (PE/PP blend).

[44] The laminate material is a thin material that is used as an internal material and/or an external material for providing waterproofing attributes. When the laminate material is used as the internal material, it acts as an inner wall of the liner 10. When the laminate material is used as an external material, it acts as an external wall of the liner 10. The laminate material acts as a further continuous physical barrier to block the ingress of moisture external to the liner 10. The laminate material is comprised of a polymer component that is preferably the same as one of the polymer components found in the parent material. In this example, the polymer component of the laminate material is one or more types of polyethylene. However, it would be appreciated by those skilled in the art that more than one laminate material may be used, so as to provide a reinforced inner or external material, or a woven material 12 that has both the internal material and the external material. Furthermore, those skilled in the art could appreciate suitable types of polypropylene or PE/PP blend in place of the polyethylene.

[45] The weld at the weld area 22 is used to seal the base of the liner 10 to prevent moisture ingress into the interior of the liner 10. In this example, the weld is conducted with an apparatus that receives and clamps the weld area 22 before subjecting the woven material 12 to a plurality of heating cycles.

[46] The advantage provided by the combination of the parent material and the laminate material is further demonstrated during the welding process. As the parent material contains a polymer component that is the same as that of the laminate material, the act of welding will enable the lamination to bind better to the parent material as heat transfer is improved and the

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2020 heated polymer components flow better. This ensures that the parent material and laminate material bind together with greater mechanical strength, resulting in the barrier created by the

2020204052 17 Jun weld between the exterior and interior of the liner 10 being superior.

[47] In a preferred embodiment, the hollow body 14 is configured in a gusseted format as illustrated by Figure 3. The gusseted format results in the hollow body 14 having four layers 28, 30, 32, 34 to be sealed on the edges and two layers in the middle 36, 38.

[48] The method of producing the liner 10 will now be described in more detail.

[49] The production of the thermoplastic liner 10 for use as a moisture barrier involves initially manufacturing a woven thermoplastic material 12. The woven material 12 is configured to substantially block the ingress of moisture due to its construction containing a parent material and a laminate material. The process of manufacturing the woven material 12 comprises weaving a plurality of strands comprising one or more types of polyethylene or polypropylene or PE/PP blend running in a vertical direction, and a plurality of strands comprising one or more types of polyethylene or polypropylene or PE/PP blend running in a horizontal direction, to form a parent material. Additionally, the woven material 12 contains a laminate material that is laminated to the parent material either as an internal laminate material or an external laminate material. However, it would be appreciated by those skilled in the art that more than one laminate material may be laminated to the parent material so that there is an internal laminate material and an external laminate material. A hollow body 14 is then produced using the woven material 12, so that the hollow body has two openings 16, 18. A base 20 is created on the hollow body 14 by welding closed one of the two openings by using pulsed application of heat to the weld area.

[50] Referring to Figure 4, there is shown a welded thermoplastic liner 10 having electrically conductive additives 40 within the parent or laminate material. The electrically conductive additives can include carbon or metal among others, and can be in the form of a strip such as thread, yarn or foil. Preferably there is at least one conductive thread running the length of the liner, more preferably several spaced around the cross-sectional circumference. In an embodiment there may be spaced apart conductive threads running around the cross-sectional circumference of the tube, more preferably intersecting so as to form an electrical connection with the lengthways extending thread(s).

[51] Referring to Figure 5, there is shown a welded closed thermoplastic liner 10 being inserted into a blast hole 42 and generating static electricity 44. This often occurs when the

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liner is inserted into a blast hole 42. In order to overcome this problem, conductive additives are inserted into the material of the liner within either the parent or the laminate material, as

2020204052 17 Jun shown in Figure 4. The welded closed thermoplastic liner of Figure 4 is then inserted into the blast hole 42 of Figure 6, and as shown, the thermoplastic liner is grounded 46 by the presence of the conductive additives and static electrical charges do not accumulate.

[52] Modifications may be made to the present invention within the context of that described and shown in the drawings. Such modifications are intended to form part of the invention described in this specification.

Claims (15)

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2020 Claims Claims

2020204052 17 Jun 1. 1. A thermoplastic liner for use as a moisture barrier, comprising: a hollow tubular body made from a woven thermoplastic material configured to substantially block the ingress of moisture; an opening at one end of the hollow tubular body for intake into the hollow of the hollow tubular body;and a closed opposite end to form a base configured to substantially block the ingress of moisture external to the hollow tubular body; wherein the woven thermoplastic material is comprised of a parent material and at least one laminate material; and wherein the parent material is comprised of polymer components; and the polymer components are configured as a plurality of strands in the vertical direction comprising at least one type of polyethylene or polypropylene or blend thereof, and as a plurality of strands in the horizontal direction comprising at least one type of polyethylene or polypropylene or blend thereof.

2. 2. A thermoplastic liner according to claim 1, wherein the at least one laminate material is configured to be an internal laminate and/or an external laminate.

3. 3. A thermoplastic liner according to claim 1 or claim 2, wherein the at least one laminate material is comprised of the same thermoplastic material as the parent material.

4. 4. A thermoplastic liner according to any one of claims 1 to 3, wherein the hollow tubular body is configured in a gusseted format.

5. 5. A thermoplastic liner according to any one of claims 1 to 4, wherein the thermoplastic material, parent material, and/or laminate material, comprises electrically conductive additives.

6. 6. A thermoplastic liner according to claim 5, wherein the electrically conductive material grounds the thermoplastic liner so as to prevent creation of a static charge.

7. A thermoplastic liner according to claim 5 or claim 6, wherein the thermoplastic material comprises electrically conductive thread woven through the thermoplastic material.

8. 8. A method of producing a thermoplastic liner for use as a moisture barrier, comprising: manufacturing a woven thermoplastic material configured to substantially block the ingress of moisture; producing a hollow body having at least two openings within the woven thermoplastic material; creating a base on the hollow body by closing one of the at least two openings; 2020204052 17 wherein the manufacturing of the woven thermoplastic material is comprised of weaving a plurality of strands running in a vertical direction comprising at least one type of polyethylene or polypropylene or blend thereof, and a plurality of strands running in a horizontal direction comprising at least one type of polyethylene or polypropylene or blend thereof, to form a parent material; and wherein the manufacturing of the woven thermoplastic material further comprises laminating an internal laminate material and/or an external laminate material to the parent material.

9. 9. A method of producing a thermoplastic liner according to claim 8, wherein the woven thermoplastic material comprises an electrically conductive additive formed in one or more thermoplastics of the thermoplastic material.

10. A method of producing a thermoplastic liner according to claim 9, wherein the electrically conductive additive comprises a powdered conductor.

11. A method of producing a thermoplastic liner according to claim 9 or claim 10, wherein the electrically conductive additive comprises an electrically conductive thread woven through the thermoplastic material.

12. A method of producing a thermoplastic liner according to any one of claims 8 to 11, wherein the hollow tubular body is configured to comprise a gusset in at least one side of the hollow tubular body such that the hollow tubular body is able to be flattened with the respective gussets formed from folds of the hollow tubular body, such that in the flattened state the tube is more readily stored in a narrow form, but is expandable when the gusset is unfolded.

13. A thermoplastic liner for use as a moisture barrier, comprising: a hollow tubular body made from a woven thermoplastic material configured to substantially block the ingress of moisture; an opening at one end of the hollow tubular body for intake into the hollow of the hollow tubular body; and an electrically conducting strip running substantially the length of the body; wherein the woven thermoplastic material is comprised of a parent material and at least one laminate material.

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14. A method of lining a bore hole comprising: providing a thermoplastic liner having a hollow tubular body made from a woven thermoplastic material configured to substantially block the ingress of moisture; an opening at one end of the hollow tubular body for intake into the hollow of the hollow tubular body; and an electrically conducting strip running substantially the length of the body; wherein the woven thermoplastic material is comprised of a parent material and at least one laminate material; and closing an end of the thermoplastic liner; inserting the thermoplastic liner into the bore hole; whereby in use in the event of any electrical charge being generated along the length of the liner, the electrically conducting thread aiding in discharging of the electrical charge.

15. A method according to claim 14, wherein the end is closed by welding.