High strength packages and packaging materials
View Patent ↗A package includes at least one closed end including a pair of opposed package panels, each face of the pair of opposed package faces including an interior side and an exterior face, at least one panel comprising a woven polymer material, wherein the interior faces of the package panels are joined to one another to define an interior joined area, the joined panels being folded towards and joined to the exterior face of the package to define a second joined area.
1. A package comprising:
a packaging material comprising a laminate, the laminate comprising a woven polymer substrate having opposite first and second faces, a first heat seal layer mounted to the first face of the substrate, and a second heat seal layer mounted to the second face of the substrate;
the packaging material being configured as a tubular structure so that a first panel of the packaging material and a second panel of the packaging material are in an opposed, facing relationship with one another, the first panel and the second panel each having an interior side, an exterior side, and an end edge, wherein the woven polymer substrate is positioned at least along the respective end edge of the first panel or the second panel;
at least one sealed closed end of the tubular structure, the sealed closed end comprising
a first sealed area comprising a portion of the first heat seal layer of the interior side of the first panel and a portion of the first heat seal layer of the interior side of the second panel being heat sealed to one another in a facing, contacting relationship with each other; and
a second sealed area comprising at least a portion of the first sealed area folded over and heat sealed to the exterior side of the first panel, such that a portion of the second heat seal layer of the exterior side of the first panel of the first sealed area and an adjacent portion of the second heat seal layer of the exterior side of the first panel are heat sealed to one another in a facing, contacting relationship with each other; and
the woven polymer substrate having a softening temperature at which the woven polymer substrate will soften, and each of the first and second heat seal layers having a heat seal temperature that is lower than the softening temperature of the woven polymer substrate,
wherein
the woven polymer substrate comprises woven polypropylene,
the first heat seal layer comprises low density polyethylene,
the first heat seal layer being mounted to the first face of the substrate comprises a tie layer of the laminate being positioned between the first heat seal layer and the first face of the substrate,
the tie layer comprises a polymer blend comprising linear low density polyethylene and low density polyethylene, and
the polymer blend includes more of the linear low density polyethylene than the low density polyethylene.
2. The package of claim 1 , wherein the first sealed area and the second sealed area are in an at least partially superposed configuration.
3. The package of claim 1 , wherein the first sealed area and the second sealed area each comprise the end edge of each of the first panel and the second panel.
4. The package of claim 1 , wherein the first sealed area comprises a pinch seal.
5. The package of claim 1 , wherein the second sealed area comprises a foldover seal.
6. The package of claim 1 , wherein
the first sealed area and the second sealed area each have a first dimension extending along the length of the package and a second dimension extending along the width of the package, and
the first dimension of the first sealed area is substantially the same as the first dimension of the second sealed area.
7. The package of claim 1 , wherein
the first sealed area and the second sealed area each have a first dimension extending along the length of the package and a second dimension extending along the width of the package, and
the first dimension of the first sealed area is greater than the first dimension of the second sealed area.
8. The package of claim 1 , wherein
the first sealed area and the second sealed area each have a first dimension extending along the length of the package and a second dimension extending along the width of the package, and
the second dimension of the first sealed area is greater than the second dimension of the second sealed area.
9. The package of claim 1 , further comprising a third sealed area, the third sealed area comprising the second sealed area folded over and joined to the second panel such that the exterior side of the second panel of the second sealed area is in a facing, contacting relationship with another portion of the exterior side of the second panel.
10. The package of claim 9 , wherein the second sealed area and the third sealed area are in an at least partially superposed relationship with one another.
11. The package of claim 10 , wherein
the second sealed area and the third sealed area each have a first dimension extending along the length of the package and a second dimension extending along the width of the package, and
the first dimension of the second sealed area is substantially the same as the first dimension of the third sealed area.
12. The package of claim 11 , wherein
the first sealed area has a first dimension extending along the length of the package and a second dimension extending along the width of the package, and
the first dimension of first sealed area is greater than the respective first dimensions of the second sealed area and the third sealed area.
13. The package of claim 12 , wherein the first sealed area includes a marginal area of the package proximate to the end of the package.
14. The package of claim 12 , wherein the second sealed area and the third sealed area are spaced from the end of the package.
15. The package of claim 13 , wherein the first sealed area comprises a cutout.
16. The package of claim 1 , wherein:
the tie layer is a first tie layer,
the laminate further comprises a second tie layer; and
the second heat seal layer being mounted to the second face of the substrate comprises the second tie layer being positioned between the second heat seal layer and the second face of the substrate.
17. The package of claim 1 , wherein the woven polymer substrate has a softening temperature of about 350 degrees Fahrenheit.
18. The package of claim 1 , wherein the heat seal temperature of each of the first and second heat seal layers is less than about 350 degrees Fahrenheit.
19. The package of claim 1 , wherein the heat seal temperature of each of the first and second heat seal layers is in a range from about 250 degrees Fahrenheit to about 300 degrees Fahrenheit.
20. The package of claim 19 , wherein the woven polymer substrate has a softening temperature of about 350 degrees Fahrenheit.
21. The package of claim 1 , wherein individual filaments of the woven polypropylene have a denier of from about 500 to about 1600.
22. The package of claim 1 , wherein for each heat seal layer of the first heat seal layer and the second heat seal layer, the heat seal layer:
comprises a thermoplastic polymer; and
has a thickness from about 0.4 mil to about 1.5 mil.
23. The package of claim 1 , wherein the first heat seal layer comprises a polymer blend comprising:
the linear low density polyethylene of the first heat seal layer,
low density polyethylene and
an ethylene methacrylic acid copolymer.
24. The package of claim 1 , wherein:
the low density polyethylene of the first heat seal layer is linear low density polyethylene; and
the polymer blend further comprises an ethylene methacrylic acid copolymer.
25. The package of claim 1 , wherein the end edge of the first panel and the end edge of the second panel are substantially straight.
26. A package comprising:
a packaging material comprising a laminate, the laminate comprising a woven polymer substrate having opposite first and second faces, a first heat seal layer mounted to the first face of the substrate, and a second heat seal layer mounted to the second face of the substrate;
the packaging material being configured as a tubular structure so that a first panel of the packaging material and a second panel of the packaging material are in an opposed, facing relationship with one another, the first panel and the second panel each having an interior side, an exterior side, and an end edge, wherein the woven polymer substrate is positioned at least along the respective end edge of the first panel or the second panel;
at least one sealed closed end of the tubular structure, the sealed closed end comprising
a first sealed area comprising a portion of the first heat seal layer of the interior side of the first panel and a portion of the first heat seal layer of the interior side of the second panel being heat sealed to one another in a facing, contacting relationship with each other; and
a second sealed area comprising at least a portion of the first sealed area folded over and heat sealed to the exterior side of the first panel, such that a portion of the second heat seal layer of the exterior side of the first panel of the first sealed area and an adjacent portion of the second heat seal layer of the exterior side of the first panel are heat sealed to one another in a facing, contacting relationship with each other; and
the woven polymer substrate having a softening temperature at which the woven polymer substrate will soften, and each of the first and second heat seal layers having a heat seal temperature that is lower than the softening temperature of the woven polymer substrate,
wherein
the woven polymer substrate comprises woven polypropylene,
the first heat seal layer comprises linear low density polyethylene,
the first heat seal layer being mounted to the first face of the substrate comprises a tie layer of the laminate being positioned between the first heat seal layer and the first face of the substrate,
the tie layer comprises a polymer blend comprising linear low density polyethylene, low density polyethylene and an ethylene methacrylic acid copolymer,
the laminate further comprises a core layer positioned between the first heat seal layer and the tie layer,
the core layer comprises polypropylene and low density polyethylene, and
the core layer includes more of the polypropylene than the low density polyethylene.
27. The package of claim 26 , wherein:
the tie layer is a first tie layer,
the laminate further comprises a second tie layer; and
the second heat seal layer being mounted to the second face of the substrate comprises the second tie layer being positioned between the second heat seal layer and the second face of the substrate.
28. The package of claim 26 , wherein the polymer blend includes more of the linear low density polyethylene than the low density polyethylene.
29. The package of claim 26 , wherein the end edge of the first panel and the end edge of the second panel are substantially straight.
30. The package of claim 29 , wherein:
the tie layer is a first tie layer,
the laminate further comprises a second tie layer; and
the second heat seal layer being mounted to the second face of the substrate comprises the second tie layer being positioned between the second heat seal layer and the second face of the substrate.