U.S. patent application number 13/804304 was filed with the patent office on 2014-01-16 for film structures containing a biaxially oriented film with two extruded polyolefin layers.
This patent application is currently assigned to TORAY PLASTICS (AMERICA), INC.. The applicant listed for this patent is TORAY PLASTICS (AMERICA), INC.. Invention is credited to John HOLOVACH, Paige MANUEL, Jon Ian MONTCRIEFF, Scott NARKEVICIUS, Gordon Vincent SHARPS, Roberto SIU.
Application Number | 20140017474 13/804304 |
Document ID | / |
Family ID | 48748041 |
Filed Date | 2014-01-16 |
United States Patent
Application |
20140017474 |
Kind Code |
A1 |
NARKEVICIUS; Scott ; et
al. |
January 16, 2014 |
FILM STRUCTURES CONTAINING A BIAXIALLY ORIENTED FILM WITH TWO
EXTRUDED POLYOLEFIN LAYERS
Abstract
Film structures containing a biaxially oriented film with an
extruded polyolefin layer on each side of the biaxially oriented
film are obtained. One polyolefin layer may, for example, be fin
sealed to exhibit a peelable heat sealable performance. The other
polyolefin layer may exhibit a paper like appearance and may be lap
sealable.
Inventors: |
NARKEVICIUS; Scott; (South
Kingstown, RI) ; SHARPS; Gordon Vincent; (N.
Kingstown, RI) ; MONTCRIEFF; Jon Ian; (Foxborough,
MA) ; SIU; Roberto; (Providence, RI) ;
HOLOVACH; John; (N. Kingstown, RI) ; MANUEL;
Paige; (N. Kingstown, RI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TORAY PLASTICS (AMERICA), INC. |
N. KIingstown |
RI |
US |
|
|
Assignee: |
TORAY PLASTICS (AMERICA),
INC.
N. Kingstown
RI
|
Family ID: |
48748041 |
Appl. No.: |
13/804304 |
Filed: |
March 14, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61670028 |
Jul 10, 2012 |
|
|
|
Current U.S.
Class: |
428/220 ;
156/244.11; 156/244.24; 428/339; 428/349 |
Current CPC
Class: |
B32B 27/20 20130101;
B32B 2439/70 20130101; B32B 2250/24 20130101; Y10T 428/2826
20150115; B32B 2250/03 20130101; B32B 2307/31 20130101; B32B
2307/518 20130101; B32B 7/06 20130101; B32B 2307/41 20130101; B32B
27/32 20130101; Y10T 428/269 20150115; B32B 27/205 20130101; B32B
27/08 20130101; B65D 65/40 20130101 |
Class at
Publication: |
428/220 ;
428/349; 428/339; 156/244.11; 156/244.24 |
International
Class: |
B65D 65/40 20060101
B65D065/40 |
Claims
1. A film structure comprising: a biaxially oriented film
comprising a first side and a second side; an extruded peelable,
heat sealable polyolefin layer on the first side of the biaxially
oriented film; and an extruded paper-like polyolefin layer on the
second side of the biaxially oriented film.
2. The film structure of claim 1, wherein the extruded peelable,
heat sealable polyolefin layer is directly on the first side of the
biaxially oriented film.
3. The film structure of claim 1, wherein the extruded paper-like
polyolefin layer is directly on the second side of the biaxially
oriented film.
4. The film structure of claim 1, wherein the extruded peelable,
heat sealable layer has a 200-3000 gm/in peelable heat seal
strength when fin sealed at 350.degree. F., 0.5 sec, and 30
psia.
5. The film structure of claim 1, wherein the extruded paper-like
polyolefin layer has an opacity value in the 40-80 range.
6. The film structure of claim 1, wherein the extruded peelable,
heat sealable polyolefin layer is 5-300 microns thick.
7. The film structure of claim 1, wherein the extruded paper-like
polyolefin layer is 5-200 microns thick.
8. The film structure of claim 1, wherein the film structure has a
total thickness of less than 20 mils.
9. The film structure of claim 1, wherein the extruded paper-like
polyolefin layer is extrusion coated on a matte chill roll to
enhance the opacity.
10. A method of making a film structure comprising: extrusion
coating a first side of a biaxially oriented film with a peelable,
heat sealable polyolefin layer; and extrusion coating a second side
of the biaxially oriented film with a paper-like polyolefin
layer.
11. The method of claim 10, further comprising chilling the
extrusion coated second side of the biaxially oriented film on a
matte chill roll to enhance the opacity.
12. The method of claim 10, further comprising fin sealing the
peelable, heat sealable polyolefin layer.
13. The method of claim 10, further comprising lap sealing the
paper-like polyolefin layer.
14. The method of claim 10, further comprising using a finishing
process on the paper-like polyolefin layer to allow for a paper
like texture.
15. The method of claim 10, wherein the peelable, heat sealable
layer has a 200-3000 gm/in peelable heat seal strength when fin
sealed at 350.degree. F., 0.5 sec, and 30 psia.
16. The method of claim 10, further comprising coloring or tinting
the paper-like polyolefin layer to provide an opacity value in the
40-80 range.
17. The method of claim 10, wherein the peelable, heat sealable
polyolefin layer is 5-300 microns thick.
18. The method of claim 10, wherein the paper-like polyolefin layer
is 5-200 microns thick.
19. The method of claim 10, wherein the film structure has a total
thickness of less than 20 mils.
20. The method of claim 10, further comprising forming a food
package from the film structure.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Patent Application Ser. No. 61/670,028, filed Jul. 10, 2012, the
entirety of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to film structures containing a
biaxially oriented film with two extruded polyolefin layers which
can exhibit a peelable heat seal performance on one side of the
film structure and a paper-like appearance and feel on the other
side.
BACKGROUND OF THE INVENTION
[0003] The food packaging industry is constantly in search of
stronger, more durable bags that are easy to open and that provide
an old fashioned, traditional look, such as the look that paper
provides.
[0004] The food packaging industry is also searching for
compositions that enable bags to be made at a lower cost.
Accordingly, attempts have been made to reduce cost by using thin
films because bags fabricated from lower thickness films typically
require less materials to produce. The amount of thermoplastic
elastomer used to make a film directly correlates to the overall
cost of manufacturing the bag. Therefore, it is desirable to use
lower thickness films to reduce the amount of material used, and
thus the cost of the film. It is also desired to improve the seal
strengths of conventional bags in order to reduce the cost of
materials, while at the same time, make them peelable.
[0005] Furthermore, it is desired that some conventional bags form
a barrier to gases and moisture from the outside environment. Bags
that exhibit good barrier properties, such as being able to reduce
or eliminate moisture and gas migration though the bag, are also
desired. Oxygen migration in particular should be minimized because
any oxygen that enters the bag may cause the contents of the bag,
such as meat products, to spoil and/or discolor.
SUMMARY OF THE INVENTION
[0006] Described are film structures containing a biaxially
oriented film with two extruded polyolefin layers. The film
structure can exhibit both a peelable heat seal performance and a
paper-like appearance.
[0007] In one embodiment, the film structure may include a
biaxially oriented film. One side of the biaxially oriented film
may include an extruded peelable, heat sealable polyolefin layer.
On the side of the biaxially oriented film opposite the extruded
peelable, heat sealable polyolefin layer, there can be an extruded
paper-like polyolefin layer. The extruded peelable, heat sealable
polyolefin layer and/or the extruded paper-like polyolefin layer
may be directly on the side of the biaxially oriented film.
Preferably, the film structure has a total thickness of less than
20 mils.
[0008] The extruded peelable, heat sealable polyolefin layer may
have a 200-3000 gm/in peelable heat seal strength when fin sealed
at 350.degree. F., 0.5 sec, and 30 psia. Preferably, the extruded
peelable, heat sealable polyolefin layer is 5-300 microns
thick.
[0009] The extruded paper-like polyolefin layer may be extrusion
coated on a matte chill roll to enhance the opacity. Preferably,
the extruded paper-like polyolefin layer has an opacity value in
the 40-80 range. In addition, the extruded paper-like polyolefin
layer may be 5-200 microns thick.
[0010] A method of making a film structure can include extrusion
coating a first side of a biaxially oriented film with a peelable,
heat sealable polyolefin layer and extrusion coating a second side
of the biaxially oriented film with a paper-like polyolefin layer.
The method can further include chilling the extrusion coated second
side of the biaxially oriented film on a matte chill roll to
enhance the opacity.
[0011] In addition, a method of making a film structure may include
fin sealing the peelable, heat sealable polyolefin layer and/or lap
sealing the paper-like polyolefin layer. A finishing process can be
used on the paper-like polyolefin layer to allow for a paper like
texture. Preferably, the film structure can be formed into a food
package.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a cross sectional view of a film structure
containing a biaxially oriented film with two extruded polyolefin
layers.
DETAILED DESCRIPTION OF THE INVENTION
[0013] This invention relates to film structures containing a
biaxially oriented film with two extruded polyolefin layers. The
extrusion coated film structures can exhibit on one side a peelable
heat seal performance when fin sealed, whereas on the other side
they can exhibit a paper like appearance and feel, which can, for
example, be lap sealed. The described film structures allow for
cost effective and manufacturing efficient processing of value
added films to be used in variety of packaging applications. The
film structures can be expanded to include metalized films, barrier
films or extruded layers, tinted films or extruded layers, energy
management films or colored extruded layers. The extruded layer can
provide fin or lap seals to the ultimate package and those seals
can be peelable.
[0014] In some embodiments, the film structure can include a
biaxially oriented film on which polyolefin layers can be extruded
on either side of the biaxially oriented film. A cross sectional
view of such an embodiment containing a biaxially oriented film
with two extruded polyolefin layers is depicted in FIG. 1. One side
of the extrusion coated film structure can be fin sealed to exhibit
a peelable heat seal performance, whereas the other side can be lap
sealed.
[0015] The biaxially oriented film can be selected from a group
consisting of oriented polystyrene, oriented crystalline and
semi-crystalline polyester and copolyester, oriented amorphous
copolyester and polyester, oriented polypropylene, oriented
polyamide, oriented polylactic acid, acrylics, and
polycarbonates.
[0016] The polyolefin layers can include a polymer or blend of
polymers selected from a group consisting of low density
polyethylene, linear low-density polyethylene, medium density
polyethylene, high-density polyethylene, propylene-ethylene
copolymers; ethylene/vinyl acetate copolymer (EVA);
ethylene/methacrylate copolymer; ethylene/n-butyl acrylate;
ethylene/vinyl acetate/carbon monoxide; ethylene/acrylic acid
(EAA); ethylene/methacrylic acid (EMAA); ionomeric salts of
ethylene/carboxylic acid copolymers such as sodium, zinc or
potassium ionomers of EMAA or EAA; maleic anhydride grafted EVA;
maleic anhydride grafted linear low-density polyethylene; and
maleic anhydride grafted polypropylene.
[0017] The extruded polyolefin layers applied on either side of the
biaxially oriented film can have different thicknesses. One side
can be thicker for fin seal performance. That thickness is
typically in the 5 to 300 micron range. The fin sealable side
typically provides peelable seals in the 200 to 3,000 gm/in range
when sealed at 350.degree. F., 0.5 sec, and 30 psia. The other side
can be thinner for lap seal performance. That thickness is
typically in the 5 to 200 micron range. The lap sealable side is
typically colored or tinted to provide an opacity value in the 40
to 80 range. A finishing process can allow for a paper like texture
on the lap sealable layer. The side with the paper like surface can
be extrusion coated on a matte chill roll to enhance the opacity of
such surface.
[0018] The extrusion coated film used in the present invention can
have any total thickness desired, so long as the film provides the
desired properties for the particular packaging operation in which
the film is used. Preferably, the film has a total thickness of
less than about 20 mils, more preferably the film has a total
thickness of about 0.25 to 20 mils, still more preferably of about
0.25 to 10 mils, and yet still more preferably, of about 0.5 to 5
mils.
[0019] This application discloses several numerical ranges. The
numerical ranges disclosed inherently support any range or value
within the disclosed numerical ranges even though a precise range
limitation is not stated verbatim in the specification because this
invention can be practiced throughout the disclosed numerical
ranges.
[0020] The above description is presented to enable a person
skilled in the art to make and use the invention, and is provided
in the context of a particular application and its requirements.
Various modifications to the preferred embodiments will be readily
apparent to those skilled in the art, and the generic principles
defined herein may be applied to other embodiments and applications
without departing from the spirit and scope of the invention. Thus,
this invention is not intended to be limited to the embodiments
shown, but is to be accorded the widest scope consistent with the
principles and features disclosed herein. Finally, the entire
disclosure of the patents and publications referred in this
application are hereby incorporated herein by reference.
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