eval™ resins the better barrier for food resins – the better barrier for food...
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EVAL™ Resins – The Better Barrier for Food Applications
EVAL™ Resins – Keeping Flavors In and Quality High
EVAL™
UsEd in Food AppLicAtionsKuraray EVALTM manufactures industry-leading ethylene vinyl alcohol (EVOH)
copolymer resins in the United States and market them in the Americas. EVAL™
resins are characterized by their outstanding gas barrier properties; resistance
to solvents, chemicals and hydrocarbons; and excellent barrier to odor and
flavor permeation, making them an outstanding solution for a variety of food
packaging applications. Their exceptional gas barrier properties make EVAL™
resins an excellent choice for flexible and rigid food packaging applications.
EVAL™ is normally used as a discrete layer in multilayer structures. EVAL™ resins
help keep oxygen out and flavor and quality in.
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• Outstanding oxygen barrier
• Preserves flavor and locks in aroma
• Retains a modified atmosphere
• Prevents flavor scalping
• Preserves oxygen sensitive vitamins and antioxidants
• Extends shelf life
• Protects food from developing off-odor and off-flavor due to penetration of volatile contaminants
• Can be used to make transparent structures
• Allows for metal detector inspection
thE BEnEFits
EVAL™ Resins – Keeping Flavors In and Quality High
EVAL™ REsins Food AppLicAtions
incLUdE
FLExIBLE Food PAcKAgIng
RIgId conTAInERs
THERmoFoRmEd sHEETs
coATIngs
TuBEs
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pRocEssing MEthod
EVAL™ can be processed using common polymer processing techniques including co-extrusion blow molding, thin wall co-injection molding, sheet co-extrusion, pipe and tube co-extrusion, multilayer cast or blown film, and co-extrusion coating.
conVEntionAL And spEciALty gRAdEs
grade selection depends on the primary and secondary processing methods as well as the required performance of the final product. Kuraray manufactures EVAL™ grades for food packaging with ethylene content ranging from 27 – 48 mol%. conventional grades cover the vast majority of packaging and processing needs. specialty products are also available to meet more demanding secondary processes such as reheat stretch blow molding, solid phase pressure thermoforming, and double or triple bubble shrink film.
polyolefin permebility @ 20˚c, 65%Rh
EVAL™ F series 0.4
EVAL™ E series 1.5
PVdc copolymer (extrusion grade) 2.6
oriented nylon 38.0
oriented PET 54.0
HdPE 2300.0
cast PP 3000.0
Pc 5000.0
LdPE 10000.0
EVA 18000.0
Unit: cc•20µm/m2•day•atm
in FLEXiBLE pAckAging, An EVALtM BARRiER LAyER oFFERs:
UsEd in Food AppLicAtions
• Oxygen, flavor and aroma barrier
• Extended shelf life and reliable barrier
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pRopERtiEs oF BARRiER MAtERiALs in FLEXiBLE Food pAckAging
EVAL™
FLEXiBLE Food pAckAging
Food manufacturers want packaging that extends shelf life and is aesthetically pleasing to the consumer.
Material density g/cc
permeability @ 20˚c, 65%RH Unit: cc•20µm/m2•day•atm
typical thickness in Flexible packaging µm
EVAL™ F series 1.14 0.4 5
EVAL™ E series 1.19 1.5 5
PVdc copolymer (extrusion grade) 1.7 2.6 10
Aluminum Foil 2.7 — 7–9
• Transparency and metal detection
• Economic, sustainable packaging
0
0 50
0.5
1
1.5
2
2.5
3
3.5
4
Oxy
gen
Tran
smis
sion
Rat
e(c
c/10
0sq
.in.d
ay.a
tm -
20
C/6
5%R
H)
Gelbo Flex Cycles (n)
38mol% EVOHmet PET
met BOPP
dURABiLity oF BARRiER MAtERiALs in FLEXiBLE Food pAckAging
Food packaging must also withstand a considerable amount of abuse that is inherent to the fabrication and actual use of the package. mechanical abuse can reduce the barrier properties of the packaging resulting in a decrease in shelf life. coextrusions of EVAL™ resins can provide more reliable food protection than traditional metalized films and foil laminations. gelbo flex is an industry standard (AsTm F193-92) used to measure the abuse resistance of barrier films.
Figure 1 shows the OTR dependency on gelbo flex cycles of three different structures. The data demonstrates the superior abuse resistant of the EVAL coextrusion relative to two different foil laminations.
A similar behavior is observed in Figure 2 when the abuse resistance of an EVAL coextrusion is compared to two different metalized film laminations.
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Figure 2 EVoH and metallized PET or BoPP 38mol% EVoH = coextrusion of PE/tie/EVoH/tie/PE = 20/7/7/7/38 µm
met PET = lamination of PE/met-PET//PE = 22/15/32 µm
met BoPP = lamination of PE/met-BoPP/PE = 39/18/51 µm
Figure 1 EVoH and foil 32mol% EVoH = coextrusion of PE/tie/EVoH/tie/PE = 65/5/12/5/65 µm
nylon/Foil = lamination of oPA/PE/foil/tie/PE = 20/12/8/12/100 µm
nylon = lamination of PE/tie/foil/tie/PE= 65/12/8/12/38 µm
FLEXiBLE Food pAckAging
0
0 10 30 50
0.02
0.04
0.06
0.08
0.1
0.12
0.14
Oxy
gen
Tran
smis
sion
Rat
e(c
c/10
0sq
.in.d
ay.a
tm -
20
C/6
5%R
H)
Gelbo Flex Cycles (n)
32mol% EVOHNylon/Foil
Foil
FigURE 1 oXygEn BARRiER Vs. FLEX cRAck cycLEs
FigURE 2 oXygEn BARRiER Vs. FLEX cRAck cycLEs
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Application typical structure (out/in)
standup pouch (beef jerky, trail mix, mayonnaise) PET/PE/tie/EVAL™/tie/PE
microwavable standup pouch (tomato sauce) PET/PE/tie/PA/EVAL™/PA/tie/coPP
Pillow pouch (potato chips and other snacks)PP/tie/cavitated EVAL™/BoPP
PP/tie/EVAL™/metal/BoPP
Pillow pouch (uHT milk, water, juice, vegetable oil) PE/tie/EVAL™/tie/PE
Bag-in-box (wine, cola syrup, smoothie, olive oil) PE/tie/EVAL™/tie/PE/PE
Vacuum pouch (meat, processed meat)PE/tie/EVAL™/tie/PE
PE/tie/EVAL™/tie/Ionomer
Forming film (processed meat, cheese)
coPP/PP/tie/PA/EVAL™/PA/tie/PE/mLL
coPP/PP/tie/PA/EVAL™/PA/tie/PE/mLL
PP/tie/PA/EVAL™/PA/tie/PE
PA/tie/PA/EVAL™/PA/tie/PE
PE/tie/PA/EVAL™/PA/tie/PE
PA/EVAL™/PA/tie/PE
Lidding film for lamination (typically to PET)mLL/PE/tie/PA/EVAL™/PA/tie/PE/mLL
mLL/PE/tie/ EVAL™/tie/PE/mLL
PE/tie/EVAL™/tie/PE
shrink films (double bubble process)
PET/tie/PE/tie/PA/EVAL™/PA/tie/Ionomer
PE/tie/PA/EVAL™/PA/tie/Ionomer
PE/tie/PA/EVAL™/PA/tie/PE
PA/ EVAL™/PA/tie/PE
PE/tie/EVAL™/tie/PE
EVA/tie/EVAL™/tie/EVA
pRocEssing MEthods
cast film, blown film, biaxially (tenter frame) oriented films, biaxially (double bubble) oriented films.
typicAL gRAdEs
EVALtM Ethylene content
Brown Film
cast Films
tenter Frame oriented Films
solid-phase pressure Forming
shrink Films
27 mol% L171 L171
32 mol% F171 F171, F104 F104 for nylon J171 sP482, xEP-1297
38 mol% H171 H171 xEP-1035 xEP-1232
44 mol% E171 E171, E105 sP292 sP292
48 mol% g176 g176 for PP g176
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EVAL™
Rigid contAinERsRigid containers such as blow molded bottles and canisters and injection molded bottles and thin wall containers must prevent oxygen ingress and maintain flavor, aroma and vitamins while being aesthetically pleasing and convenient to the consumer.
Application typical structure (out/in)
Ketchup, juices, health supplements
PP/tie/Regrind/EVALTm/Regrind/tie/PP
PP/tie/EVALTm/Regrind/tie/PP
uHT milk HdPE/tie/EVALTm/tie/HdPE
coffee, nuts, dry snacks
HdPE/tie/EVALTm
Application typical structure (out/in)
Beer, carbonated beverages
PET/EVAL™/PET/EVAL™/PET
Juices PET/EVAL™/PET
Pet food, baby food, diced fruit
PP/EVAL™/PP
CO-INJECTION
typicAL gRAdEs
EVALtM Ethylene content
pp/EVoh or hdpE/EVoh Extrusion blow molding
pEt/EVoh coinjection
pp/EVoh coinjection
27 mol% L171
32 mol% F171 sP434 xEP-1248
All standard EVAL™ grades are used in typical thermal processing methods of food. However, in the case of retort sterilization, Polypropylene based structures must be used. specific maximum EVoH layer thickness and minimum Polypropylene layer thickness requirements are outlined on the food compliance letters for each product. High performance grades have also been developed for continued aluminum foil, metal can and glass substitution. clear oxygen scavenging EVAL™ can be used to extend the shelf life of retort and non-retort food packages. desiccant-containing EVAL™, suitable for opaque containers, can suppress the typical retort shock of EVoH experienced during steam sterilization.
CO-EXTRUSION BLOW MOLDING
pRocEssing MEthods
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crystal-clear and attractive, plastic barrier cups and trays represent a fast-growing segment in the packaging market. The most important requirement for this kind of thermoformed sheet packaging is that it protects the flavor of the contents, keeping it fresh for long periods of time, even in non-refrigerated conditions. designed especially for this market, various grades of EVAL™ provides excellent oxygen barriers and superior transparency in a variety of PP- and Ps-based structures. Even under deep forming conditions, these EVAL™ types provide uniform layer distribution.
co-extruded multilayer thermoformed cups with an oxygen barrier layer of EVAL™ can easily be pasteurized and show remarkable resistance against deformation upon thermal treatment.
EVAL™
thERMoFoRMEd shEEt
Applicationtypical structure (out/in)
soup, pet food, baby food, peanut butter, diced fruit, applesauce, seafood, ready-to-eat meals
PP/tie/EVAL™/tie/PP
Pudding, gelatin dessert, marmalades, baby food, coffee pods, creamers
Ps/tie1/EVAL™/tie2/PE
Fresh pasta, deli, refrigerated food
PET/tie1/EVAL™/tie2/PE
deli, cheese, snacks PLA/tie1/EVAL™/tie2/PE
typicAL gRAdEs
The selection of grades will depend on the structural polymer used in the co-extruded sheet and the draw ratio of the specific package.
EVALtM Ethylene content pp ps, pEt,
pLA, coc
27 mol% LT171, sP521 sP521
32 mol% J171 J171
38 mol% H171, xEP-1035 H171, xEP-1035
ShEET CO-EXTRUSION aND ThERMOfORMING
pRocEssing MEthods
EVAL™
tUBEs
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In coating applications, an EVAL™ layer provides significant advantages over conventional aluminum foil while providing good formability of the board and coating composition.
Tube packaging offers a welcome alternative for many food products traditionally packaged in glass bottles. One of the many advantages of plastic tubes containing an EVAL™ layer is that they provide excellent gas barrier. The tubes are also flexible and easy to squeeze without losing their shape, even after frequent usage.
Application typical structure (out/in)
Table top juice PE/paper/PA/EVAL™/tie/PE
oatmeal, condiment pouches, tea
Paper/PE/tie/EVAL™/tie/PE Paper/tie/EVAL™/tie/PE Paper/tie/EVAL™/tie
Application typical structure (out/in)
Peanut butter, sauces PE/tie/EVAL™/tie/PE
typicAL gRAdEs
High melt index grades are recommended for extrusion coating processes. The workhorse of the industry is the 35 mol% ethylene EVAL™ c109 grade. EVAL™ LT174 is a 27 mol% ethylene option for higher barrier.
typicAL gRAdEs
EVAL F171 (32 mol% et.) and EVAL E105 (44 mol% et.) are predominantly used in squeezable tube applications. E105 provides a balance of flexibility and barrier for numerous cosmetic applications. of the two grades, F171 is used to meet the requirements for the packaging of more oxygen sensitive and chemically aggressive food and non-food products.
pRocEssing MEthods
pRocEssing MEthods
EVAL™
coAtings
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EVAL™ ethylene vinyl alcohol (EVOH) copolymer resins are characterized by their outstanding gas barrier properties and by their excellent process ability.
The key to this balance of characteristics is the combination of the proper copolymerization ratio of ethylene to vinyl alcohol. Kuraray’s unique proprietary manufacturing process has produced the world’s widest available range of EVOH grades.
EVAL™ M type offers superior barrier performance for automotive applications.
EVAL™ L type has very low ethylene content and is suitable as an ultra-high barrier grade in several applications.
EVAL™ F type offers superior barrier performance and is widely used for automotive, bottle, film, tube and pipe applications.
EVAL™ c type can be used for high-speed co-extrusion coating and cast flexible applications.
EVAL™ h type has a perfect balance between high barrier properties and long-term run stability and is especially suitable for blown film.
EVAL™ E type has a higher ethylene content which allows for greater flexibility and even easier processing. different versions have been specially designed for cast and blown film as well as for pipe.
EVAL™ g type has the highest ethylene content, making it the best candidate among standard EVAL™ grades for stretch and shrink film applications.
EVAL™ sp resins are a new family of resins that combine the gas barrier performance of traditional EVoH resins with improved orientability. This “softer” EVoH is ideal for applications where orientation is key and more flexible barrier polymer is needed.
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48 mol%
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44 mol%
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38 mol%
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35 mol%
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32 mol%
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27 mol%
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24 mol% M
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EVAL™ is a registered trademark of Kuraray co. Ltd.
hEAdqUARtERs
2625 Bay Area Blvd., suite 600 Houston, Tx 77058
Tel: (800) 423-9762 Fax: (281) 204-4622
REsEARch & tEchnicAL cEntER
11500 Bay Area Blvd. Pasadena, Tx 77507
www.kuraray.us.com
Rev 8/2012