Note: Descriptions are shown in the official language in which they were submitted.
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PACKAGING WITH THREE-DIMENSIONAL LOOP MATERIAL
BACKGROUND
[0001] Many fresh foods such as such as meat, poultry, fish, vegetables,
fruits, and berries
are packaged in plastic trays with a shrink wrap or stretch wrap film for
protection, unitization
and transportation. These trays are typically thermoformed trays made from
rigid- or semi-
rigid materials such as polystyrene or polypropylene sheets. The fresh food
item typically
contains liquid that drains or flows from the food item during storage. The
liquid accumulates
in the bottom of the package. Liquid accumulation increases the risk of
microbiological growth,
which can deteriorate the fresh food, rendering the food unsafe for
consumption. Liquid
accumulation in the fresh food package also negatively impacts the appearance
of the food
item, during consumers away from purchasing the food item.
[0002] Conventional fresh food packaging utilizes an absorbent pad between
the food
item and the tray. Absorbent pads are typically made of cellulose pulp and/or
super absorbent
polyacrylates, encased in a non-woven textile wrapping bag. Absorbent pads can
only retain
the drained liquid to a limited extent. Absorbent pads do not completely
eliminate
microbiological growth inside of the food package because the liquid remains
in contact with
the food item at the interface of the absorbent pad. Also, the liquid in the
absorbent pad
remains in either liquid form or hydrogel form, increasing the risk of
microbiological growth.
Biocides cannot typically be used inside of absorbent packages or absorbent
pads due to food
contact regulations. Further, absorbent pads are known to easily tear and/or
adhere to a food
item when consumers remove the food item from a package, forcing consumers to
contact the
absorbent pad.
[0003] The art therefore recognizes the need for a food package that is
capable of
preventing liquid accumulation and minimizing microbiological growth without
the need for an
absorbent pad.
SUMMARY
[0004] The present disclosure provides a packaging article. In an
embodiment, the
packaging article comprises (A) a rigid container having side walls and a
bottom wall, the walls
defining a compartment, and (B) a sheet of 3-dimensional random loop material
(3DRLM) in the
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compartment. A food item (C) may be located in the compartment, the food item
contacts the
sheet of 3DRLM.
DEFINITIONS AND TEST METHODS
[0005]
All references to the Periodic Table of the Elements herein shall refer to the
Periodic
Table of the Elements, published and copyrighted by CRC Press, Inc., 2003.
Also, any references
to a Group or Groups shall be to the Groups or Groups reflected in this
Periodic Table of the
Elements using the IUPAC system for numbering groups. Unless stated to the
contrary, implicit
from the context, or customary in the art, all components and percents are
based on weight.
For purposes of United States patent practice, the contents of any patent,
patent application,
or publication referenced herein are hereby incorporated by reference in their
entirety (or the
equivalent US version thereof is so incorporated by reference).
[0006]
The numerical ranges disclosed herein include all values from, and including,
the
lower value and the upper value. For ranges containing explicit values (e.g.,
1, or 2, or 3 to 5, or
6, or 7) any subrange between any two explicit values is included (e.g., 1 to
2; 2 to 6; 5 to 7; 3 to
7; 5 to 6; etc.).
[0007]
Unless stated to the contrary, implicit from the context, or customary in the
art, all
components and percents are based on weight, and all test methods are current
as of the filing
date of this disclosure.
[0008]
Apparent density. A sample material is cut into a square piece of 38 cm x 38
cm
(15 in x 15 in) in size. The volume of this piece is calculated from the
thickness measured at
four points. The division of the weight by the volume gives the apparent
density (an average of
four measurements is taken) with values reported in grams per cubic
centimeter, g/cc.
[0009]
Bending Stiffness. The bending stiffness is measured in accordance with DIN
53121 standard, with compression molded plaques of 550 p.m thickness, using a
Frank-PTI
Bending Tester. The samples are prepared by compression molding of resin
granules per ISO
293 standard. Conditions for compression molding are chosen per ISO 1872 ¨
2007 standard.
The average cooling rate of the melt is 15 C/min. Bending stiffness is
measured in 2-point
bending configuration at room temperature with a span of 20 mm, a sample width
of 15 mm,
and a bending angle of 40 . Bending is applied at 6 /second (s) and the force
readings are
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obtained from 6 to 600 s, after the bending is complete. Each material is
evaluated four times
with results reported in Newton millimeters ("Nmm").
[0010] "Blend," "polymer blend" and like terms is a composition of two or
more polymers.
Such a blend may or may not be miscible. Such a blend may or may not be phase
separated.
Such a blend may or may not contain one or more domain configurations, as
determined from
transmission electron spectroscopy, light scattering, x-ray scattering, and
any other method
known in the art. Blends are not laminates, but one or more layers of a
laminate can comprise
a blend.
[0011] 13C Nuclear Magnetic Resonance (NMR)
[0012] Sample Preparation
[0013] The samples are prepared by adding approximately 2.7 g of a 50/50
mixture of
tetrachloroethane-d2/orthodichlorobenzene that is 0.025M in chromium
acetylacetonate
(relaxation agent) to 0.21 g sample in a 10 mm NMR tube. The samples are
dissolved and
homogenized by heating the tube and its contents to 150 C.
[0014] Data Acquisition Parameters
[0015] The data is collected using a Bruker 400 MHz spectrometer equipped
with a Bruker
Dual DUL high-temperature CryoProbe. The data is acquired using 320 transients
per data file,
a 7.3 sec pulse repetition delay (6 sec delay+1.3 sec acq. time), 90 degree
flip angles, and
inverse gated decoupling with a sample temperature of 125 C. All measurements
are made on
non-spinning samples in locked mode. Samples are homogenized immediately prior
to
insertion into the heated (130 C) NMR Sample changer, and are allowed to
thermally
equilibrate in the probe for 15 minutes prior to data acquisition.
[0016] "Composition" and like terms is a mixture of two or more materials.
Included in
compositions are pre-reaction, reaction and post-reaction mixtures, the latter
of which will
include reaction products and by-products as well as unreacted components of
the reaction
mixture and decomposition products, if any, formed from the one or more
components of the
pre-reaction or reaction mixture.
[0017] The terms "comprising," "including," "having," and their
derivatives, are not
intended to exclude the presence of any additional component, step or
procedure, whether or
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not the same is specifically disclosed. In order to avoid any doubt, all
compositions claimed
through use of the term "comprising" may include any additional additive,
adjuvant, or
compound, whether polymeric or otherwise, unless stated to the contrary. In
contrast, the
term, "consisting essentially of" excludes from the scope of any succeeding
recitation any other
component, step or procedure, excepting those that are not essential to
operability. The term
"consisting of" excludes any component, step or procedure not specifically
delineated or listed.
[0018] Crystallization Elution Fractionation (CEF) Method
[0019] Comonomer distribution analysis is performed with Crystallization
Elution
Fractionation (CEF) (PolymerChar in Spain) (B Monrabal et al, Macromol. Symp.
257, 71-79
(2007)). Ortho-dichlorobenzene (ODCB) with 600 ppm antioxidant butylated
hydroxytoluene
(BHT) is used as solvent. Sample preparation is done with autosampler at 160 C
for 2 hours
under shaking at 4 mg/ml (unless otherwise specified). The injection volume is
300 p.m. The
temperature profile of CEF is: crystallization at 3 C/min from 110 C to 30 C,
the thermal
equilibrium at 30 C for 5 minutes, elution at 3 C/min from 30 C to 140 C. The
flow rate during
crystallization is at 0.052 ml/min. The flow rate during elution is at 0.50
ml/min. The data is
collected at one data point/second. CEF column is packed by the Dow Chemical
Company with
glass beads at 125 p.m + 6% (MO-SCI Specialty Products) with 1/8 inch
stainless tubing. Glass
beads are acid washed by MO-SCI Specialty with the request from The Dow
Chemical Company.
Column volume is 2.06 ml. Column temperature calibration is performed by using
a mixture of
NIST Standard Reference Material Linear polyethylene 1475a (1.0 mg/ml) and
Eicosane (2
mg/ml) in ODCB. Temperature is calibrated by adjusting elution heating rate so
that NIST linear
polyethylene 1475a has a peak temperature at 101.0 C, and Eicosane has a peak
temperature
of 30.0 C. The CEF column resolution is calculated with a mixture of NIST
linear polyethylene
1475a (1.0 mg/ml) and hexacontane (Fluka, purum, >97.0, 1 mg/ml ). A baseline
separation of
hexacontane and NIST polyethylene 1475a is achieved. The area of hexacontane
(from 35.0 to
67.0 C) to the area of NIST 1475a from 67.0 to 110.0 C is 50 to 50, the amount
of soluble
fraction below 35.0 C is <1.8 wt%. The CEF column resolution is defined in the
following
equation:
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Resolution
Peak temperature of NIST 1475a ¨ Peak Temperature of Hexacontane
= ________________________________________________________________________
Half ¨ height Width of NIST 1475a + Half ¨ height Width of Hexacontane
[0020] where the column resolution is 6Ø
[0021] Density is measured in accordance with ASTM D 792 with values
reported in grams
per cubic centimeter, g/cc.
[0022] Differential Scanning Calorimetry (DSC). Differential Scanning
Calorimetry (DSC) is
used to measure the melting and crystallization behavior of a polymer over a
wide range of
temperatures. For example, the TA Instruments 01000 DSC, equipped with an
RCS
(refrigerated cooling system) and an autosampler is used to perform this
analysis. During
testing, a nitrogen purge gas flow of 50 ml/min is used. Each sample is melt
pressed into a thin
film at about 175 C; the melted sample is then air-cooled to room temperature
(approx. 25 C).
The film sample is formed by pressing a "0.1 to 0.2 gram" sample at 175 C at
1,500 psi, and 30
seconds, to form a "0.1 to 0.2 mil thick" film. A 3-10 mg, 6 mm diameter
specimen is extracted
from the cooled polymer, weighed, placed in a light aluminum pan (ca 50 mg),
and crimped
shut. Analysis is then performed to determine its thermal properties. The
thermal behavior of
the sample is determined by ramping the sample temperature up and down to
create a heat
flow versus temperature profile. First, the sample is rapidly heated to 180 C,
and held
isothermal for five minutes, in order to remove its thermal history. Next, the
sample is cooled
to -40 C, at a 10 C/minute cooling rate, and held isothermal at -40 C for five
minutes. The
sample is then heated to 150 C (this is the "second heat" ramp) at a 10
C/minute heating rate.
The cooling and second heating curves are recorded. The cool curve is analyzed
by setting
baseline endpoints from the beginning of crystallization to -20 C. The heat
curve is analyzed by
setting baseline endpoints from -20 C to the end of melt. The values
determined are peak
melting temperature (Tm), peak crystallization temperature (Tc), onset
crystallization
temperature (Tc onset), heat of fusion (Hf) (in Joules per gram), the
calculated % crystallinity for
polyethylene samples using: % Crystallinity for PE = ((Hf)/(292 J/g)) x 100,
and the calculated %
crystallinity for polypropylene samples using: % Crystallinity for PP =
((Hf)/165 J/g)) x 100. The
heat of fusion (Hf) and the peak melting temperature are reported from the
second heat curve.
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Peak crystallization temperature and onset crystallization temperature are
determined from
the cooling curve.
[0023] Elastic Recovery. Resin pellets are compression molded following
ASTM D4703,
Annex Al, Method C to a thickness of approximately 5-10 mil. Microtensile test
specimens of
geometry as detailed in ASTM D1708 are punched out from the molded sheet. The
test
specimens are conditioned for 40 hours prior to testing in accordance with
Procedure A of
Practice D618.
[0024] The samples are tested in a screw-driven or hydraulically-driven
tensile tester using
flat, rubber faced grips. The grip separation is set at 22 mm, equal to the
gauge length of the
microtensile specimens. The sample is extended to a strain of 100% at a rate
of 100%/min and
held for 30s. The crosshead is then returned to the original grip separation
at the same rate
and held for 60s. The sample is then strained to 100% at the same 100%/min
strain rate.
[0025] Elastic recovery may be calculated as follows:
(Initial Applied Strain ¨ Permanent Set)
Elastic Recovery = __________________________________________ x 100%
Initial Applied Strain
[0026] An "ethylene-based polymer" is a polymer that contains more than 50
weight
percent polymerized ethylene monomer (based on the total weight of
polymerizable
monomers) and, optionally, may contain at least one comonomer. Ethylene-based
polymer
includes ethylene homopolymer, and ethylene copolymer (meaning units derived
from
ethylene and one or more comonomers). The terms "ethylene-based polymer" and
"polyethylene" may be used interchangeably. Nonlimiting examples of ethylene-
based polymer
(polyethylene) include low density polyethylene (LDPE) and linear
polyethylene. Nonlimiting
examples of linear polyethylene include linear low density polyethylene
(LLDPE), ultra low
density polyethylene (ULDPE), very low density polyethylene (VLDPE), multi-
component
ethylene-based copolymer (EPE), ethylene/a-olefin multi-block copolymers (also
known as
olefin block copolymer (OBC)), single-site catalyzed linear low density
polyethylene (m-LLDPE),
substantially linear, or linear, plastomers/elastomers, and high density
polyethylene (HDPE).
Generally, polyethylene may be produced in gas-phase, fluidized bed reactors,
liquid phase
slurry process reactors, or liquid phase solution process reactors, using a
heterogeneous
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catalyst system, such as Ziegler-Natta catalyst, a homogeneous catalyst
system, comprising
Group 4 transition metals and ligand structures such as metallocene, non-
metallocene metal-
centered, heteroaryl, heterovalent aryloxyether, phosphinimine, and others.
Combinations of
heterogeneous and/or homogeneous catalysts also may be used in either single
reactor or dual
reactor configurations.
[0027] "High density polyethylene" (or "HDPE") is an ethylene homopolymer
or an
ethylene/a-olefin copolymer with at least one C4¨C10 a-olefin comonomer, or
C4_C8 a-olefin
comonomer and a density from greater than 0.94 g/cc, or 0.945 g/cc, or 0.95
g/cc, or 0.955 g/cc
to 0.96 g/cc, or 0.97 g/cc, or 0.98 g/cc. The HDPE can be a monomodal
copolymer or a
multimodal copolymer. A "monomodal ethylene copolymer" is an ethylene/C4¨C10 a-
olefin
copolymer that has one distinct peak in a gel permeation chromatography (GPC)
showing the
molecular weight distribution. A "multimodal ethylene copolymer" is an
ethylene/C4¨C10 a-
olefin copolymer that has at least two distinct peaks in a GPC showing the
molecular weight
distribution. Multimodal includes copolymer having two peaks (bimodal) as well
as copolymer
having more than two peaks. Nonlimiting examples of HDPE include DOWTM High
Density
Polyethylene (HDPE) Resins (available from The Dow Chemical Company), ELITE"'
Enhanced
Polyethylene Resins (available from The Dow Chemical Company), CONTINUUM"'
Bimodal
Polyethylene Resins (available from The Dow Chemical Company), LUPOLENTM
(available from
LyondellBasell), as well as HDPE products from Borealis, lneos, and
ExxonMobil.
[0028] An "interpolymer" is a polymer prepared by the polymerization of at
least two
different monomers. This generic term includes copolymers, usually employed to
refer to
polymers prepared from two different monomers, and polymers prepared from more
than two
different monomers, e.g., terpolymers, tetrapolymers, etc.
[0029] "Low density polyethylene" (or "LDPE") consists of ethylene
homopolymer, or
ethylene/a-olefin copolymer comprising at least one C3¨C10 a-olefin,
preferably C3¨C4that has a
density from 0.915 g/cc to 0.940 g/cc and contains long chain branching with
broad MWD.
LDPE is typically produced by way of high pressure free radical polymerization
(tubular reactor
or autoclave with free radical initiator). Nonlimiting examples of LDPE
include MarFlexTM
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(Chevron Phillips), LUPOLENTM (LyondellBasell), as well as LDPE products from
Borealis, lneos,
ExxonMobil, and others.
[0030] "Linear low density polyethylene" (or "LLDPE") is a linear
ethylene/a-olefin
copolymer containing heterogeneous short-chain branching distribution
comprising units
derived from ethylene and units derived from at least one C3¨C10 a-olefin
comonomer or at
least one C4¨C8 a-olefin comonomer, or at least one C6¨C8 a-olefin comonomer.
LLDPE is
characterized by little, if any, long chain branching, in contrast to
conventional LDPE. LLDPE has
a density from 0.910 g/cc, or 0.915 g/cc, or 0.920 g/cc, or 0.925 g/cc to
0.930 g/cc, or 0.935
g/cc, or 0.940 g/cc. Nonlimiting examples of LLDPE include TUFLIN"' linear low
density
polyethylene resins (available from The Dow Chemical Company), DOWLEXTM
polyethylene
resins (available from the Dow Chemical Company), and MARLEXTM polyethylene
(available from
Chevron Phillips).
[0031] "Ultra low density polyethylene" (or "ULDPE") and "very low density
polyethylene"
(or "VLDPE") each is a linear ethylene/a-olefin copolymer containing
heterogeneous short-
chain branching distribution comprising units derived from ethylene and units
derived from at
least one C3¨C10 a-olefin comonomer, or at least one C4¨C8 a-olefin comonomer,
or at least one
C6¨C8 a-olefin comonomer. ULDPE and VLDPE each has a density from 0.885 g/cc,
or 0.90 g/cc
to 0.915 g/cc. Nonlimiting examples of ULDPE and VLDPE include ATTANE"' ultra
low density
polyethylene resins (available form The Dow Chemical Company) and FLEXOMERTm
very low
density polyethylene resins (available from The Dow Chemical Company).
[0032] "Multi-component ethylene-based copolymer" (or "EPE") comprises
units derived
from ethylene and units derived from at least one C3¨C10 a-olefin comonomer,
or at least one
C4¨C8 a-olefin comonomer, or at least one C6¨C8 a-olefin comonomer, such as
described in
patent references USP 6,111,023; USP 5,677,383; and USP 6,984,695. EPE resins
have a density
from 0.905 g/cc, or 0.908 g/cc, or 0.912 g/cc, or 0.920 g/cc to 0.926 g/cc, or
0.929 g/cc, or 0.940
g/cc, or 0.962 g/cc. Nonlimiting examples of EPE resins include ELITE"'
enhanced polyethylene
(available from The Dow Chemical Company), ELITE Arm advanced technology
resins (available
from The Dow Chemical Company), SURPASSTM Polyethylene (PE) Resins (available
from Nova
Chemicals), and SMART"' (available from SK Chemicals Co.).
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[0033] "Single-site catalyzed linear low density polyethylenes" ( or "m-
LLDPE") are linear
ethylene/a-olefin copolymers containing homogeneous short-chain branching
distribution
comprising units derived from ethylene and units derived from at least one
C3¨C10 a-olefin
comonomer, or at least one C4¨C8 a-olefin comonomer, or at least one C6¨C8 a-
olefin
comonomer. m-LLDPE has density from 0.913 g/cc, or 0.918 g/cc, or 0.920 g/cc
to 0.925 g/cc,
or 0.940 g/cc. Nonlimiting examples of m-LLDPE include EXCEEDTM metallocene PE
(available
from ExxonMobil Chemical), LUFLEXENTM m-LLDPE (available from LyondellBasell),
and ELTEX"'
PF m-LLDPE (available from lneos Olefins & Polymers).
[0034] "Ethylene plastomers/elastomers" are substantially linear, or
linear, ethylene/a-
olefin copolymers containing homogeneous short-chain branching distribution
comprising units
derived from ethylene and units derived from at least one C3¨C10 a-olefin
comonomer, or at
least one C4¨C8 a-olefin comonomer, or at least one C6¨C8 a-olefin comonomer.
Ethylene
plastomers/elastomers have a density from 0.870 g/cc, or 0.880 g/cc, or 0.890
g/cc to 0.900
g/cc, or 0.902 g/cc, or 0.904 g/cc, or 0.909 g/cc, or 0.910 g/cc, or 0.917
g/cc. Nonlimiting
examples of ethylene plastomers/ elastomers include AFFINITY"' plastomers and
elastomers
(available from The Dow Chemical Company), EXACT"' Plastomers (available from
ExxonMobil
Chemical), Tafmer"' (available from Mitsui), NexleneTM (available from SK
Chemicals Co.), and
LuceneTM (available LG Chem Ltd.).
[0035] Melt flow rate (MFR) is measured in accordance with ASTM D 1238,
Condition
280 C/2.16 kg (g/10 minutes).
[0036] Melt index (MI) is measured in accordance with ASTM D 1238,
Condition 190 C/2.16
kg (g/10 minutes).
[0037] "Melting Point" or "Tm" as used herein (also referred to as a
melting peak in
reference to the shape of the plotted DSC curve) is typically measured by the
DSC (Differential
Scanning Calorimetry) technique for measuring the melting points or peaks of
polyolefins as
described in USP 5,783,638. It should be noted that many blends comprising two
or more
polyolefins will have more than one melting point or peak, many individual
polyolefins will
comprise only one melting point or peak.
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[0038] Molecular weight distribution (Mw/Mn) is measured using Gel
Permeation
Chromatography (GPC). In particular, conventional GPC measurements are used to
determine
the weight-average (Mw) and number-average (Mn) molecular weight of the
polymer and to
determine the Mw/Mn. The gel permeation chromatographic system consists of
either a
Polymer Laboratories Model PL-210 or a Polymer Laboratories Model PL-220
instrument. The
column and carousel compartments are operated at 140 C. Three Polymer
Laboratories 10-
micron Mixed-B columns are used. The solvent is 1,2,4 trichlorobenzene. The
samples are
prepared at a concentration of 0.1 grams of polymer in 50 milliliters of
solvent containing 200
ppm of butylated hydroxytoluene (BHT). Samples are prepared by agitating
lightly for 2 hours
at 160 C. The injection volume used is 100 microliters and the flow rate is
1.0 ml/minute.
[0039] Calibration of the GPC column set is performed with 21 narrow
molecular weight
distribution polystyrene standards with molecular weights ranging from 580 to
8,400,000,
arranged in 6 "cocktail" mixtures with at least a decade of separation between
individual
molecular weights. The standards are purchased from Polymer Laboratories
(Shropshire, UK).
The polystyrene standards are prepared at 0.025 grams in 50 milliliters of
solvent for molecular
weights equal to or greater than 1,000,000, and 0.05 grams in 50 milliliters
of solvent for
molecular weights less than 1,000,000. The polystyrene standards are dissolved
at 80 C with
gentle agitation for 30 minutes. The narrow standards mixtures are run first
and in order of
decreasing highest molecular weight component to minimize degradation. The
polystyrene
standard peak molecular weights are converted to polyethylene molecular
weights using the
following equation (as described in Williams and Ward, J. Polym. Sci., Polym.
Let., 6, 621
(1968)):
M polypropylene=0.645(M polystyrene).
[0040] Polypropylene equivalent molecular weight calculations are performed
using
Viscotek TriSEC software Version 3Ø
[0041] An "olefin-based polymer," as used herein, is a polymer that
contains more than 50
weight percent polymerized olefin monomer (based on total amount of
polymerizable
monomers), and optionally, may contain at least one comonomer. Nonlimiting
examples of
olefin-based polymer include ethylene-based polymer and propylene-based
polymer.
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[0042] A "polymer" is a compound prepared by polymerizing monomers, whether
of the
same or a different type, that in polymerized form provide the multiple and/or
repeating
"units" or "mer units" that make up a polymer. The generic term polymer thus
embraces the
term homopolymer, usually employed to refer to polymers prepared from only one
type of
monomer, and the term copolymer, usually employed to refer to polymers
prepared from at
least two types of monomers. It also embraces all forms of copolymer, e.g.,
random, block, etc.
The terms "ethylene/a-olefin polymer" and "propylene/a-olefin polymer" are
indicative of
copolymer as described above prepared from polymerizing ethylene or propylene
respectively
and one or more additional, polymerizable a-olefin monomer. It is noted that
although a
polymer is often referred to as being "made of" one or more specified
monomers, "based on" a
specified monomer or monomer type, "containing" a specified monomer content,
or the like, in
this context the term "monomer" is understood to be referring to the
polymerized remnant of
the specified monomer and not to the unpolymerized species. In general,
polymers herein are
referred to has being based on "units" that are the polymerized form of a
corresponding
monomer.
[0043] A "propylene-based polymer" is a polymer that contains more than 50
weight
percent polymerized propylene monomer (based on the total amount of
polymerizable
monomers) and, optionally, may contain at least one comonomer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] FIG. 1 is an exploded perspective view of a packaging article in
accordance with an
embodiment of the present disclosure.
[0045] FIG. 1A is an enlarged perspective view of Area 1A of FIG. 1.
[0046] FIG. 2 is a perspective view of the packaging article of FIG. 1.
[0047] FIG. 2A is a sectional view taken along line 2A-2A of FIG. 2.
[0048] FIG. 3 is an exploded perspective view of a packaging article in
accordance with
another embodiment of the present disclosure.
[0049] FIG. 4 is a perspective view of the packaging article of FIG. 3.
[0050] FIG. 4A is a sectional view taken along line 4A-4A of FIG. 4.
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[0051] FIG. 5 is a perspective view of a packaging article in accordance
with another
embodiment of the present disclosure.
[0052] FIG. 5A is a sectional view taken along line 5A-5A of FIG.5.
DETAILED DESCRIPTION
[0053] The present disclosure provides a packaging article. In an
embodiment, the
packaging article includes (A) a rigid container having side walls and a
bottom wall. The walls
define a compartment. The packaging article also includes (B) a sheet of 3-
dimensional random
loop material (3DRLM) in the compartment.
A. Container
[0054] Referring to the drawings and initially to FIGS. 1-2, a packaging
article is indicated
generally by the reference numeral 10. The packaging article 10 includes a
container 12. The
container 12 includes sidewalls 14, a bottom wall 16 and an optional top wall
18. The sidewalls
14 extend between the bottom wall 16 and an optional top wall 18. Although
FIG. 1 shows
container 12 with four sidewalls 14, it is understood that the container can
have from, three, or
four, to five, or six, or seven, or eight, or more sidewalls.
[0055] The top wall 18 is optional. The container 12 can have an open
top¨void of a top
wall. When the top wall is present, the top wall 18 may or may not be attached
to one or more
sidewalls.
[0056] In an embodiment, the top wall is present and the top wall is a
discrete stand-alone
component, that is placed on the sidewalls, forming a closed compartment
(along with the
bottom wall). Attachment between the stand-alone top wall may be by way of
snap-fit,
friction-fit, and combinations thereof.
[0057] In an embodiment, the top wall 18 is present and is hingedly
attached to a sidewall
14, to provide a claimshell container as shown in FIGS. 1-2. A "clamshell
container" is a rigid
container with a top portion (top wall 18 wall) and a bottom portion (walls 14-
16), the top
portion heat formed to the bottom portion by way of a hinge 19. Clamshell
containers are
popular because they are inexpensive, versatile, provide excellent protection
to food items
such as produce, and present a pleasing consumer package. Clamshell containers
are most
often used with consumer packs of high value produce items like small fruit,
berries,
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mushrooms, etc., or items that are easily damaged by crushing. Clamshells
containers are used
extensively with precut produce and prepared salads.
[0058] The walls 14-16 (an optionally top wall 18) form a compartment 20.
The
compartment 20 is accessible by removing the top wall 18 (when present) from
the sidewalls
14.
[0059] The walls 14-18 are made of a rigid material. Nonlimiting examples
of suitable
material for the walls 14-18 include cardboard, corrugated cardboard,
polymeric material,
metal, wood, fiberglass, insulative material, and any combination thereof.
[0060] The container may comprise two or more embodiments disclosed herein.
B. Sheet of 3-dimensional random loop material
[0061] The packaging article 10 includes at least one sheet 22 of a 3-
dimensional random
loop material 30. As shown in FIG. 1A, a "3-dimensional random loop material"
(or "3DRLM") is
a mass or a structure of a multitude of loops 32 formed by allowing continuous
fibers 34, to
wind, permitting respective loops to come in contact with one another in a
molten state and to
be heat-bonded, or otherwise melt-bonded, at most of the contact points 36.
Even when a
great stress to cause significant deformation is given, the 3DRLM 30 absorbs
the stress with the
entire net structure composed of three-dimensional random loops melt-
integrated, by
deforming itself; and once the stress is lifted, elastic resilience of the
polymer manifests itself to
allow recovery to the original shape of the structure. When a net structure
composed of
continuous fibers made from a known non-elastic polymer is used as a
cushioning material,
plastic deformation is developed and the recovery cannot be achieved, thus
resulting in poor
heat-resisting durability. When the fibers are not melt-bonded at contact
points, the shape
cannot be retained and the structure does not integrally change its shape,
with the result that a
fatigue phenomenon occurs due to the concentration of stress, thus
unbeneficially degrading
durability and deformation resistance. In certain embodiments, melt-bonding is
the state
where all contact points are melt-bonded.
[0062] A nonlimiting method for producing 3DRLM 30 includes the steps of
(a) heating a
molten olefin-based polymer, at a temperature 10 C-140 C higher than the
melting point of the
polymer in a typical melt-extruder; (b) discharging the molten interpolymer to
the downward
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direction from a nozzle with plural orifices to form loops by allowing the
fibers to fall naturally
(due to gravity). The polymer may be used in combination with a thermoplastic
elastomer,
thermoplastic non-elastic polymer or a combination thereof. The distance
between the nozzle
surface and take-off conveyors installed on a cooling unit for solidifying the
fibers, melt
viscosity of the polymer, diameter of orifice and the amount to be discharged
are the elements
which decide loop diameter and fineness of the fibers. Loops are formed by
holding and
allowing the delivered molten fibers to reside between a pair of take-off
conveyors (belts, or
rollers) set on a cooling unit (the distance therebetween being adjustable),
bringing the loops
thus formed into contact with one another by adjusting the distance between
the orifices to
this end such that the loops in contact are heat-bonded, or otherwise melt-
bonded, as they
form a three-dimensional random loop structure. Then, the continuous fibers,
wherein contact
points have been heat-bonded as the loops form a three-dimensional random loop
structure,
are continuously taken into a cooling unit for solidification to give a net
structure. Thereafter,
the structure is cut into a desired length and shape. The method is
characterized in that the
olefin-based polymer is melted and heated at a temperature 10 C-140 C higher
than the
melting point of the interpolymer and delivered to the downward direction in a
molten state
from a nozzle having plural orifices. When the polymer is discharged at a
temperature less than
C higher than the melting point, the fiber delivered becomes cool and less
fluidic to result in
insufficient heat-bonding of the contact points of fibers.
[0063] Properties, such as, the loop diameter and fineness of the fibers
constituting the
cushioning net structure provided herein depend on the distance between the
nozzle surface
and the take-off conveyor installed on a cooling unit for solidifying the
interpolymer, melt
viscosity of the interpolymer, diameter of orifice and the amount of the
interpolymer to be
delivered therefrom. For example, a decreased amount of the interpolymer to be
delivered
and a lower melt viscosity upon delivery result in smaller fineness of the
fibers and smaller
average loop diameter of the random loop. On the contrary, a shortened
distance between the
nozzle surface and the take-off conveyor installed on the cooling unit for
solidifying the
interpolymer results in a slightly greater fineness of the fiber and a greater
average loop
diameter of the random loop. These conditions in combination afford the
desirable fineness of
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the continuous fibers of from 100 denier to 100000 denier and an average
diameter of the
random loop of not more than 100 mm, or from 1 millimeter (mm), or 2 mm, or 10
mm to 25
mm, or 50 mm. By adjusting the distance to the aforementioned conveyor, the
thickness of the
structure can be controlled while the heat-bonded net structure is in a molten
state and a
structure having a desirable thickness and flat surface formed by the
conveyors can be
obtained. Too great a conveyor speed results in failure to heat-bond the
contact points, since
cooling proceeds before the heat-bonding. On the other hand, too slow a speed
can cause
higher density resulting from excessively long dwelling of the molten
material. In some
embodiments the distance to the conveyor and the conveyor speed should be
selected such
that the desired apparent density of 0.005-0.1 g/cc or 0.01-0.05 g/cc can be
achieved.
[0064] In an embodiment, the 3DRLM 30 has, one, some, or all of the
properties (i) ¨ (iii)
below:
[0065] (i) an apparent density from 0.016 g/cc, or 0.024 g/cc, or 0.032
g/cc, or 0.040
g/cc, or 0.050 g/cc, or 0.060 to 0.070, or 0.080, or 0.090, or 0.100, or
0.150; and/or
[0066] (ii) a fiber diameter from 0.1 mm, or 0.5 mm, or 0.7 mm, or 1.0 mm
or 1.5 mm to
2.0 mm to 2.5 mm, or 3.0 mm; and/or
[0067] (iii) a thickness (machine direction) from 1.0 cm, 2.0 cm, or 3.0,
cm, or 4.0 cm, or
5.0 cm, or 10 cm, or 20 cm, to 50 cm, or 75 cm, or 100 cm, or more. It is
understood that the
thickness of the 3DRLM 30 will vary based on the type of product to be
packaged.
[0068] The 3DRLM 30 is formed into a three dimensional geometric shape to
form a sheet
(i.e., a prism). The 3DRLM 30 is an elastic material which can be compressed
and stretched and
return to its original geometric shape. An "elastic material," as used herein,
is a rubber-like
material that can be compressed and/or stretched and which expands/retracts
very rapidly to
approximately its original shape/length when the force exerting the
compression and/or the
stretching is released. The three dimensional random loop material 30 has a
"neutral state"
when no compressive force and no stretch force is imparted upon the 3DRLM 30.
The three
dimensional random loop material 30 has "a compressed state" when a
compressive force is
imparted upon the 3DRLM 30. The three dimensional random loop material 30 has
"a
stretched state" when a stretching force is imparted upon the 3DRLM 30.
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[0069]
The three dimensional random loop material 30 is composed of one or more
olefin-
based polymers. The olefin-based polymer can be one or more ethylene-based
polymers, one
or more propylene-based polymers, and blends thereof.
[0070]
In an embodiment, the ethylene-based polymer is an ethylene/a-olefin polymer.
Ethylene/a-olefin polymer may be a random ethylene/a-olefin polymer or an
ethylene/a-olefin
multi-block polymer. The a-olefin is a C3-C20 a-olefin , or a C4-C12 a-olefin
, or a C4-C8 a-olefin.
Nonlimiting examples of suitable a-olefin comonomer include propylene, butene,
methyl-1-
pentene, hexene, octene, decene, dodecene, tetradecene, hexadecene,
octadecene, cyclohexyl-1-
propene (allyl cyclohexane), vinyl cyclohexane, and combinations thereof.
[0071]
In an embodiment, the ethylene-based polymer is a homogeneously branched
random ethylene/a-olefin copolymer.
[0072]
"Random copolymer" is a copolymer wherein the at least two different monomers
are arranged in a non-uniform order. The term "random copolymer" specifically
excludes block
copolymers. The term "homogeneous ethylene polymer" as used to describe
ethylene
polymers is used in the conventional sense in accordance with the original
disclosure by Elston
in U.S. Pat. No. 3,645,992, the disclosure of which is incorporated herein by
reference, to refer
to an ethylene polymer in which the comonomer is randomly distributed within a
given
polymer molecule and wherein substantially all of the polymer molecules have
substantially the
same ethylene to comonomer molar ratio. As defined herein, both substantially
linear ethylene
polymers and homogeneously branched linear ethylene are homogeneous ethylene
polymers.
[0073]
The homogeneously branched random ethylene/a-olefin copolymer may be a
random homogeneously branched linear ethylene/a-olefin copolymer or a random
homogeneously branched substantially linear ethylene/a-olefin copolymer.
The term
"substantially linear ethylene/a-olefin copolymer" means that the polymer
backbone is
substituted with from 0.01 long chain branches/1000 carbons to 3 long chain
branches/1000
carbons, or from 0.01 long chain branches/1000 carbons to 1 long chain
branches/1000
carbons, or from 0.05 long chain branches/1000 carbons to 1 long chain
branches/1000
carbons. In contrast, the term "linear ethylene/a-olefin copolymer" means that
the polymer
backbone has no long chain branching.
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[0074] The homogeneously branched random ethylene/a-olefin copolymers may
have the
same ethylene/ a-olefin comonomer ratio within all copolymer molecules. The
homogeneity of
the copolymers may be described by the SCBDI (Short Chain Branch Distribution
Index) or CDBI
(Composition Distribution Branch Index) and is defined as the weight percent
of the polymer
molecules having a comonomer content within 50 percent of the median total
molar
comonomer content. The CDBI of a polymer is readily calculated from data
obtained from
techniques known in the art, such as, for example, temperature rising elution
fractionation
(abbreviated herein as "TREF") as described in U.S. Pat. No. 4,798,081
(Hazlitt et al.), or in U.S.
Pat. No. 5,089,321 (Chum et al.) the disclosures of all of which are
incorporated herein by
reference. The SCBDI or CDBI for the homogeneously branched random ethylene/a-
olefin
copolymers is preferably greater than about 30 percent, or greater than about
50 percent.
[0075] The homogeneously branched random ethylene/a-olefin copolymer may
include at
least one ethylene comonomer and at least one C3 -C20 a-olefin, or at least
one C4-C12 a-olefin
comonomer. For example and not by way of limitation, the C3-C20 a-olefins may
include but are
not limited to propylene, isobutylene, 1-butene, 1-hexene, 4-methyl-1-pentene,
1-heptene, 1-
octene, 1-nonene, and 1-decene, or, in some embodiments, 1-butene, 1-hexene, 4-
methyl-1-
pentene and 1-octene.
[0076] The homogeneously branched random ethylene/a-olefin copolymer may
have one,
some, or all of the following properties (i) ¨ (iii) below:
[0077] (i) a melt index (12) from 1 g/10 min, or 5 g/10 min, or 10 g/10
min, or 20 g/10
min to 30 g/10 min, or 40 g/10 min, or 50 g/10 min, and/or
[0078] (ii) a density from 0.075 g/cc, or 0.880 g/cc, or 0.890 g/cc to 0.90
g/cc, or 0.91
g/cc, or 0.920 g/cc, or 0.925 g/cc; and/or
[0079] (iii) a molecular weight distribution (Mw/Mn) from 2.0, or 2.5, or
3.0 to 3.5, or 4Ø
[0080] In an embodiment, the ethylene-based polymer is a heterogeneously
branched
random ethylene/a-olefin copolymer.
[0081] The heterogeneously branched random ethylene/a-olefin copolymers
differ from
the homogeneously branched random ethylene/a-olefin copolymers primarily in
their
branching distribution. For example, heterogeneously branched random
ethylene/a-olefin
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copolymers have a distribution of branching, including a highly branched
portion (similar to a
very low density polyethylene), a medium branched portion (similar to a medium
branched
polyethylene) and an essentially linear portion (similar to linear homopolymer
polyethylene).
[0082] Like the homogeneously branched random ethylene/a-olefin copolymer,
the
heterogeneously branched random ethylene/a-olefin copolymer may include at
least one
ethylene comonomer and at least one C3-C20 a-olefin comonomer, or at least one
C4-C12 a-
olefin comonomer. For example and not by way of limitation, the C3-C20 a-
olefins may include
but are not limited to, propylene, isobutylene, 1-butene, 1-hexene, 4-methyl-1-
pentene, 1-
heptene, 1-octene, 1-nonene, and 1-decene, or, in some embodiments, 1-butene,
1-hexene, 4-
methy1-1-pentene and 1-octene. In one embodiment, the heterogeneously branched
ethylene/a-olefin copolymer may comprise greater than about 50% by wt ethylene
comonomer, or greater than about 60% by wt., or greater than about 70% by wt.
Similarly, the
heterogeneously branched ethylene/a-olefin copolymer may comprise less than
about 50% by
wt a-olefin monomer, or less than about 40% by wt., or less than about 30% by
wt.
[0083] The heterogeneously branched random ethylene/a-olefin copolymer may
have one,
some, or all of the following properties (i) ¨ (iii) below:
[0084] (i) a density from 0.900 g/cc, or 0.0910 g/cc, or 0.920 g/cc to
0.930 g/cc, or 0.094
g/cc;
[0085] (ii) a melt index (12) from 1 g/10 min, or 5 g/10 min, or 10 g/10
min, or 20 g/10 min
to 30 g/10 min, or 40 g/10 min, or 50 g/10 min; and/or
[0086] (iii) an Mw/Mn from 3.0, or 3.5 to 4.0, or 4.5.
[0087] In an embodiment, the 3DRLM 30 is composed of a blend of a
homogeneously
branched random ethylene/a-olefin copolymer and a heterogeneously branched
ethylene/a-
olefin copolymer, the blend having one, some, or all of the properties (i) ¨
(v) below:
[0088] (i) a Mw/Mn from 2.5, or 3.0 to 3.5, or 4.0, or 4.5;
[0089] (ii) a melt index (12) from 3.0 g/10 min, or 4.0 g/10 min, or 5.0
g/10 min, or 10 g/10
min to 15 g/10 min, or 20 g/10 min, or 25 g/10 min;
[0090] (iii) a density from 0.895 g/cc, or 0.900 g/cc, or 0.910 g/cc, or
0.915 g/cc to 0.920
g/cc, or 0.925 g/cc; and or
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[0091] (iv) an 110/12 ratio from 5 g/10 min, or 7 g/10 min to 10 g/10 min,
or 15 g/10 min;
and/or
[0092] (v) a percent crystallinity from 25%, or 30%, or 35%, or 40% to 45%,
or 50%, or
55%.
[0093] According to Crystallization Elution Fractionation (CEF), the
ethylene/a-olefin
copolymer blend may have a weight fraction in a temperature zone from 90 C to
115 C or
about 5% to about 15% by wt., or about 6% to about 12%, or about 8% to about
12%, or greater
than about 8%, or greater than about 9%. Additionally, as detailed below, the
copolymer blend
may have a Comonomer Distribution Constant (CDC) of at least about 100, or at
least about
110.
[0094] The present ethylene/a-olefin copolymer blend may have at least two,
or three
melting peaks when measured using Differential Scanning Calorimetry (DSC)
below a
temperature of 130 C. In one or more embodiments, the ethylene/a-olefin
copolymer blend
may include a highest temperature melting peak of at least 115 C, or at least
120 C, or from
about 120 C to about 125 C, or from about from 122 to about 124 C. Without
being bound by
theory, the heterogeneously branched ethylene/a-olefin copolymer is
characterized by two
melting peaks, and the homogeneously branched ethylene/a-olefin copolymer is
characterized
by one melting peak, thus making up the three melting peaks.
[0095] Additionally, the ethylene/a-olefin copolymer blend may comprise
from about 10 to
about 90% by weight, or about 30 to about 70% by weight, or about 40 to about
60% by weight
of the homogeneously branched ethylene/a-olefin copolymer. Similarly, the
ethylene/a-olefin
copolymer blend may comprise from about 10 to about 90% by weight, about 30 to
about 70%
by weight, or about 40 to about 60% by weight of the heterogeneously branched
ethylene/a-
olefin copolymer. In a specific embodiment, the ethylene/a-olefin copolymer
blend may
comprise from about 50% to about 60% by weight of the homogeneously branched
ethylene/a-
olefin copolymer, and 40% to about 50% of the heterogeneously branched
ethylene/a-olefin
copolymer.
[0096] Moreover, the strength of the ethylene/a-olefin copolymer blend may
be
characterized by one or more of the following metrics. One such metric is
elastic recovery.
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Here, the ethylene/a-olefin copolymer blend has an elastic recovery, Re, in
percent at 100
percent strain at 1 cycle of between 50-80%. Additional details regarding
elastic recovery are
provided in US Patent 7,803,728, which is incorporated by reference herein in
its entirety.
[0097] The ethylene/a-olefin copolymer blend may also be characterized by
its storage
modulus. In some embodiments, the ethylene/a-olefin copolymer blend may have a
ratio of
storage modulus at 25 C, G' (25 C) to storage modulus at 100 C, G' (100 C) of
about 20 to
about 60, or from about 20 to about 50, or about 30 to about 50, or about 30
to about 40.
[0098] Moreover, the ethylene/a-olefin copolymer blend may also be
characterized by a
bending stiffness of at least about 1.15 Nmm at 6 s, or at least about 1.20
Nmm at 6 s, or at
least about 1.25 Nmm at 6 s, or at least about 1.35 Nmm at 6 s. Without being
bound by
theory, it is believed that these stiffness values demonstrate how the
ethylene/a-olefin
copolymer blend will provide cushioning support when incorporated into 3DRLM
fibers bonded
to form a cushioning net structure.
[0099] In an embodiment, the ethylene-based polymer is an ethylene/a-olefin
interpolymer
composition having one, some, or all of the following properties (i)-(v)
below:
[00100] (i) a highest DSC temperature melting peak from 90.0 C to 115.0
C; and/or
[00101] (ii) a zero shear viscosity ratio (ZSVR) from 1.40 to 2.10; and/or
[00102] (iii) a density in the range of from 0.860 to 0.925 g/cc; and/or
[00103] (iv) a melt index (12) from 1 g/10 min to 25 g/10 min; and/or
[00104] (v) a molecular weight distribution (Mw/Mn) in the range of from
2.0 to 4.5.
[00105] In an embodiment, the ethylene-based polymer contains a
functionalized commoner
such as an ester. The functionalized comonomer can be an acetate comonomer or
an acrylate
comonomer. Nonlimiting examples of suitable ethylene-based polymer with
functionalized
comonomer include ethylene vinyl acetate (EVA), ethylene methyl acrylate EMA,
ethylene ethyl
acrylate (EEA), and any combination thereof.
[00106] In an embodiment, the olefin-based polymer is a propylene-based
polymer. The
propylene-based polymer can be a propylene homopolymer or a propylene/a-olefin
polymer.
The a-olefin is a C2 a-olefin (ethylene) or a C4-C12 a-olefin, or a C4-C8 a-
olefin. Nonlimiting
examples of suitable a-olefin comonomer include ethylene, butene, methyl-1-
pentene, hexene,
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octene, decene, dodecene, tetradecene, hexadecene, octadecene, cyclohexy1-1-
propene (allyl
cyclohexane), vinyl cyclohexane, and combinations thereof.
[00107] In an embodiment, the propylene interpolymer includes from 82 wt% to
99 wt%
units derived from propylene and from 18 wt% to 1 wt% units derived from
ethylene, having
one, some, or all of the properties (i) ¨ (vi) below:
[00108] (i) a density of from 0.840 g/cc, or 0.850 g/cc to 0.900 g/cc;
and/or
[00109] (ii) a highest DSC melting peak temperature from 50.0 C to 120.0 C;
and/or
[00110] (iii) a melt flow rate (MFR) from 1 g/10 min, or 2 g/10 min to 50
g/10 min, or 100
g/10 min; and/or
[00111] (iv) a Mw/Mn of less than 4; and/or
[00112] (v) a percent crystallinity in the range of from 0.5 % to 45%;
and/or
[00113] (vi) a DSC crystallization onset temperature, Tc-Onset, of less
than 85 C.
[00114] In an embodiment, the olefin-based polymer used in the manufacture
of the 3DRLM
30 contains one or more optional additives. Nonlimiting examples of suitable
additives include
stabilizer, antimicrobial agent, antifungal agent, antioxidant, processing
aid, ultraviolet (UV)
stabilizer, slip additive, antiblocking agent, color pigment or dyes,
antistatic agent, filler, flame
retardant, and any combination thereof.
[00115] Returning to FIGS. 1-2, the packaging article 10 includes a sheet
22 made of
3DRLM 30 (hereafter "sheet 22"). The sheet 22 can move to/from a compressed
state, to/from
a neutral state, and to/from a stretched state. The composition, and/or the
size, and/or the
shape of the sheet 22 can be tailored to accommodate the size and shape of the
compartment
20.
[00116] In an embodiment, the sheet 22 extends between and contacts at
least two
opposing sidewalls 14 of the container 12. In a further embodiment, the sheet
22 extends
between and contacts four sidewalls 14. Although FIGS. 1-2 show a single sheet
22, it is
understood two, three, four or more sheets can be placed within the
compartment 20. In
addition to lining the bottom wall 16, one or more additional sheets may line
one, some, or all
of the sidewalls, 14, for example. Alternatively, a single sheet may be
configured to line each
wall¨sidewalls 14 and bottom wall 16.
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[00117] In an embodiment, sheet 22 is sized and shaped to friction fit
against the four
sidewalls 14 and is also sized to line the bottom wall 16. In a further
embodiment, sheet 22 is
removable from the container 10. Sheet 22 is thereby reusable and/or
recyclable.
C. Food Item
[00118] The packaging article 10 includes a food item 24 as shown in FIGS.
1-2. The food
item 24 can be a meat item, a poultry item, a fish item, a shellfish item, a
vegetable item, a fruit
item, a berry item, derivative thereofs (such as slices and/or portions of the
food item), and
combinations thereof. Nonlimiting examples of suitable meat items include
beef, pork, lamb, and
goat. Nonlimiting examples of suitable poultry items include chicken, turkey,
and duck. Nonlimiting
examples of suitable fish items include tuna, salmon, pollock, catfish,
swordfish, tilapia, and cod.
Nonlimiting examples of suitable shellfish items include shrimp, crab,
lobster, clams, mussels,
oysters, and scallops. Nonlimiting examples of suitable fruit items include
cherries, kiwi, peppers
and tomatoes. Nonlimiting examples of suitable vegetable items include
celery, lettuce,
cauliflower, broccoli, carrots, and eggplant.
[00118] Nonlimiting examples of suitable berry items include acai berry,
amalika, baneberry,
barbados cherry, barberry, bearberry, bilberry, bittersweet berry, blackberry,
blueberry, black
mulberry, boysenberry, buffalo berry, bunchberry, chokeberry, chokecherry,
cloudberry,
cowberry, cranberry, currant, dewberry, elderberry, farkleberry, goji berry,
gooseberry, grape,
holly berry, huckleberry, Indian plum, ivy berry, juneberry, juniper berry,
lingonberry, logan
berry, mulberry, nannyberry, persimmon, pokeberry, raspberry, salmonberry,
strawberry,
sugarberry, tayberry, thimbleberry, wineberry, wintergreen, an youngberry.
[00119] The food item 24 has a liquid 26 that accumulates on and/or flows
from the food
item 24 over time during storage, as shown in FIG. 2A. The liquid 26 emanates
from the food
item 24 and thereby includes components of the food item. Nonlimiting examples
of components
of the liquid 26 include water, microorganisms, proteins, fats, blood, small
particles of the food item
(water soluble particles and/or water insoluble particles), juice from the
food item, and
combinations thereof.
[00120] The liquid 26 may manifest as a result of injury to one or more
individual pieces of the
food item during handling and/or storage, the injury triggering liquid
drainage that emanates from
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the food item. Alternatively, the food item may naturally generate excess
liquid over time during
storage as is common with fresh cut meat, raw meat, fresh fish, or chicken,
for example.
Regardless of the origin of the liquid 26, it is known that prolonged contact
between the food
item 24 and the liquid 26 is detrimental to the freshness, consumption, and
viability of the food
item 24. Over time, microorganism growth in liquid 26 can degrade the food
item 24. In sum,
contact between the food item 24 and the liquid 26 increases the risk of
spoilage to the bulk
food item in the container 12.
[00121] FIGS. 1-2 show the food item as a raspberry 24a. During processing,
handling, and/or
storage, one or more individual raspberries may be injured, causing liquid, in
this case raspberry
juice 26a, to drain from the raspberry 24a. The open loop structure of the
3DRLM 30 enables the
liquid 26a to drain through the sheet 22 and away from food item 24a. In this
way, the sheet
separates the food item 24a from the liquid 26a thereby advantageously
increasing shelf life of
the food item (the raspberries 24a), reducing spoilage of the food item, and
protecting the food
item from the liquid 26a.
[00122] FIG. 2A shows the liquid 26, as raspberry juice 26a, flowing
through the 3DRLM 30.
After flowing from the raspberries 24a, and through the 3DRLM 30, the
raspberry juice 26a
accumulates on the bottom wall 16. The sheet 22 (vis-a-vis the open loop
structure of the
3DRLM 30) enables drainage of the raspberry juice 26a from the raspberries 24a
and
concomitantly the sheet 22 separates the raspberries 24a from the raspberry
juice 26a
accumulated on the bottom wall 16. The present packaging article provides the
following
synergistic advantages: (1) drainage of liquid 26 away from the food item 24,
(2) separation
between the food item and the liquid, and (3) prevention of contact between
the food item and
the accumulated liquid on the bottom wall. In this way, the sheet 22 separates
the food item
24 from the liquid 26 thereby advantageously increasing shelf life, reducing
spoilage, and
protecting the food item 24 from the liquid 26.
[00123] The sheet 22 may include an optional a coating or a film layer
containing an
antimicrobial material that kills microorganisms or inhibits microbial growth.
[00124] In an embodiment the thickness of the sheet 22 is configured so
that all, or
substantially all, of the liquid 26 drained from the food item 24 during
storage remains away
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from, and out of contact with, the food item 24. The sheet 22 separates the
food item 24 from
the liquid 26 on the bottom wall 16.
[00125] The container 10 may or may not include ports for draining the
liquid from the
compartment 20. In an embodiment, the container 10 includes ports 40 for
draining, or
otherwise removing, the accumulated liquid from the bottom wall 16.
D. Cold source
[00125] The present disclosure provides another packaging article as shown
in FIGS. 3-5A. In
an embodiment, a packaging article 110 is provided, the packaging article 110
including a
container 112 having sidewalls 114 and a bottom wall 116. The walls 114-116
define a
compartment 120. The container 112 may include an optional top wall (not
shown). The
packaging article includes a sheet 122 of 3DRLM 130 located in the compartment
120.
[00126] In an embodiment, the container 112 is an insulated container. An
"insulated
container," as used herein is a container that that prevents, or reduces, the
passage of heat.
Nonlimiting examples of an insulated container include a vacuum flask
(ThermosTm bottle), a
container with a thermal blanket or a thermal liner, a molded expanded
polystyrene (EPS)
container, a molded polyurethane foam container, a molded polyethylene foam
container, a
container with a liner of reflective material (metallized film), a container
with a liner of bubble
wrap, and any combination thereof.
[00127] In an embodiment, the sheet 122 extends between and contacts at
least two
opposing sidewalls 114 of the container 112 as disclosed above. In a further
embodiment, the
sheet 122 extends between and contacts four sidewalls 114 as disclosed above.
Sheet 122 may
be sized and shaped to friction fit against the four sidewalls 114 and also
sized to line the
bottom wall 116 as disclosed above. Sheet 122 is removable from container 112
and is thereby
reusable and/or recyclable.
[00128] A food item 124 is present in the compartment 120.
[00129] The packaging article 110 includes a cold source 128. A "cold
source," as used
herein, is an object that produces, or radiates, cold. Nonlimiting examples of
a suitable cold
source include a wet ice pack, ice, a bottle of ice, a dry ice (frozen CO2)
pack, a refrigerant pack
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(typically water and ammonium nitrate, and including a frozen gel pack), and
any combination
thereof.
[00130] The food item 124 contacts a surface of the sheet 122 and/or contacts
the cold
source 128. The cold source 128 is placed adjacent to, and/or on top of the
food item 124.
Alternatively, the cold source 128 is placed between the sheet 122 and the
food item 124.
[00131] In an embodiment, the food item is fresh fish 124a and the cold
source is ice 128a,
as shown in FIGS. 3-5A. The fresh fish 124a contacts a surface of the sheet
122. Alternatively,
the ice 128a is placed on the sheet 122, with the fresh fish 124a placed on
the ice 128a. The ice
128a lies below, adjacent to, and on top of the fresh fish 124a. As the ice
128a melts, the fresh
fish 124a eventually contacts the sheet 122.
[00132] As the ice 128a melts, liquid 126a is formed. The liquid 126a
includes water,
particles of the fish, microbes, and other organisms from the fish, and any
combination thereof.
The liquid 126a drains through the sheet 122 by way of the open loop structure
of the 3DRLM
130, as shown in FIG. 4A. The sheet 122 separates the fresh fish 124a from the
liquid 126a
(melted ice or water) that accumulates on the bottom wall 116. In an
embodiment, the sheet
122 is sized and shaped to have sufficient height to separate the fresh fish
124a from the
accumulated liquid 126a when all the ice 128a is melted. In other words, when
all the ice 128a
is melted, the sheet 122 is thick enough to prevent contact between the fresh
fish 124a (resting
on the top surface of the sheet 122) and the liquid 126a that is accumulated
on the bottom wall
116.
[00133] In an embodiment, the container 112 includes ports 140 for draining
the
accumulated liquid 126a from the container 112 as shown in FIG. 4A.
[00134] In an embodiment, the packaging article 110 includes two
containers¨container
112 and container 212. Container 212 is the same as, or substantially the same
as, container
112. Container 212 has sidewalls 214 and bottom wall 216 the same as, or
similar to, the
respective walls 114, 116 of container 112. Containers 112, 212 are stackable
with container
212 placed upon the container 112. Container 212 matingly fits on container
112, as shown in
FIGS. 5, 5A.
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[00135] The container 212 contains a sheet 222 of 3DRLM 230, and a second
batch of the
food item, in this case, a second batch of fresh fish 224a. It is understood
that the second batch
of the food item may be the same or different food item as the original food
item. The
container also contains a cold source, ice 228a.
[00136] In an embodiment, a third sheet of 3DRLM (not shown) is placed
between the top of
container 112 and the bottom of container 212. The third sheet provides
support and stability
to the container 212 as the ice 128 in the container 112 melts.
[00137] In an embodiment, the container 212 includes ports 240 which enable
the liquid
226a to drain from the container 212. The liquid 226a drains into the
container 112 and
continues to drain through the sheet 122 and eventually to the bottom wall 116
of the
container 112. The ports 140 enable the liquid 226a (from container 212) and
the liquid 126a
to drain from the container 112.
[00138] The packaging article 110 is scalable with the provision of one,
two, three or more
containers, each container having a respective sheet of 3DRLM, respective food
item, and
optional cold source. The present packaging article 110 provides the
synergistic advantages: (1)
drainage of liquid away from the food item 24 (located in multiple
containers), (2) separation
between the food item and the liquid, and (3) prevention of contact between
the food item and
the accumulated liquid on the bottom wall.
[00139] It is specifically intended that the present disclosure not be
limited to the
embodiments and illustrations contained herein, but include modified forms of
those
embodiments including portions of the embodiments and combinations of elements
of
different embodiments as come with the scope of the following claims.
26
