1
Flexible Packaging Laminates
Lesson 8
第 8课 软包装复合材料
2
Plasticating Extruder
Ex i t
p o rt
Gea r re d u c e r
V a ri a b l e spe e d mo to r
F e e d t h ro a t
F e e d h o p p e r
Ho p p e r th ro a t
Co o l i n g j a c k e t
Sc re w
He a t e r b a n d s
Fig,10.2
3
A dj us tabl e
D i e L i p s
E x tr us i on
D i e
A dj us tabl e P r es s ur e
( R es tr i c tor ) B ar
E x tr ude r
Cast Film and Sheet Extrusion
Fig.10.4
4
E x t ru de r # 1
E x t ru de r # 2
E x t ru de r # 3
M ate ri a l # 1
M ate ri a l # 2
M ate ri a l # 3
Three-Layer Coextrusion
Fig.10.9
5
Extrusion Cast Film Line Layout
E x t ruder
E x t rusi on d i e C hi l l ro l l
E dg e tri m me r
Ma teri al ro l l
Fig.10.5
6
Machine Direction Orientation
R ot a tion x 1 x 3x 2 X 4
F r om e xtr ud er
castin g r oll s
Fig.10.8
7
Ext rud er
C as ti ng Rol l s
Ann ea l i ng Z on e
Ext rus i on Di e
T e nt er C l i ps
Cross Direction Orientation
Fig.10.8
8
Bub b l e
Blo w -u p a i r i n l e t
Coo l i n g a i r Coo l i n g a i r
Pla s ti c fro m e x tru d e r
Die l i p a d j u s ti n g b o l ts
Die Bod y
Die c o re
Fro s t l i n e
Bub b l e c o n s ta n tl y p u l l e d u p
Blown-film Die Cross-Section
Fig.10.6
9
Three-layer Extrusion Blow Mold
Cut-away view
material 1
material 2
material 3
film bubble
10
Ex t ru d e r
Cir c u l a r
d i e
Ai r ri n g
In t e rn a l b u b b l e c o o l i n g
Pl a s ti c f i l m b u b b l e
Col l a p s i n g f ra m e
Upp e r n i p ro l l s
Sl i tt e r
Dua l ro l l
win d e r
Blown Film Line With Slitter
Fig.10.7
11
Blown Film Line Showing Die & Bubble
12
Aluminum Foil
Household foil is typically 17.5 mm (0.0007 inches)
Available in gauges as low as 7 mm (0.00028 inches)
Pin holing is present below 12 mm (0.0005 inches)
Foil is susceptible to flex cracking
Most foils are supported with plastic and/or paper
Unsupported foil used for some lid-stock & tablet
push-through packaging
13
Intact foil is a 100% barrier to all gases
Best deadfold properties
Easily punctured (tamper evidence)
Reflective of radiant heat
Conductive (induction sealing)
Decorative appeal,all reflective metallics are aluminum
Aluminum Foil Characteristics
14
Foil Packaging Applications
Unsupported foil,non-sealable
e.g,confection and cheese wraps
Unsupported foil,heat sealable
e.g,lidding stock,pharmaceutical tablet
backing material
Supported foil,non heat sealable
e.g,decorative wraps,label stock
Supported foil,heat sealable
e.g,high barrier pouches and sachets
lidding stock,retort pouches
15
Aluminum Vacuum Metallizing
Fig.14.1
V a cu u m l in e
Unwin d r o l l
A luminu m v a p o r
Cera mi c b o a t
Rewin d r o l l
A luminu m
wi r e Chill e d ro l l
16
Provides reflective metallic appearance
Improves moisture,aroma,light and oxygen barrier
Oxygen barrier improved,
up to fifty times for OPP,up to ten times for PET
Static dissipative applications
OPP,PET,& PA (nylon) most common packaging films
Aluminum Metallized Film
17
Why Laminate?
There is no perfect,universal packaging material
Laminates assemble materials with individually
desirable properties to create an optimum material
Laminate,A product made by bonding together
two or more materials
18
Mechanical properties
tensile strength stiffness
coefficient of friction use temperatures
elongation formability
Laminate Properties
Barrier properties as required
oxygen barrier essential oil barrier
water vapor barrier light barrier
19
Laminate Properties
Sealability
most flexible packaging is heat sealed
most heat seals are polyethylene based
other polymers used more critical applications
Aesthetic appearance
clarity
surface gloss
reflective metallics
20
Describing Packaging Laminate
Note,
Packaging laminate plies are always
listed from the outside to the inside
21
Gravure Coating
Fig,14.8
22
Wet Bond Laminator
Fig,14.10
23 Fig,14.11
Dry Bond Laminating
24
Solventless Laminating
Solventless laminating uses catalyzed or or two-part
reactive adhesives
25
Extrusion Laminating
Fig,14.9
E xt r u si o n d ie
C h i ll r o l l
S u b s t r a t e A
S u b s t r a t e B
S t r i p - o f f r o ll
P r e ssu r e
r o ll
N ip r o ll
E xt r u d a t e Th r e e p ly
la m in a t e
26
Hot Tack
The bond strength of the seal while still hot
Critical for most form-fill-seal machines
Determines how quickly product can be dropped
into a pouch
27
Common Heat- Seal Materials
cost
bond quality
ionomer (e.g,Surlyn,seals through contaminants )
acid copolymer (good foil bond,chemical resistance)
metallocene polyethylene (low temp,fast seal)
LLDPE (good hot tack,tough,wide seal temp.)
PE/EVA (soft film,low seal temperature)
medium-density polyethylene (stiffer,better barrier)
cast polypropylene (stands higher temperatures)
low-density polyethylene
Table 14.5
28
Source,M,Lutterotti,DuPont
Sealing Mediums Compared
30 00
25 00
20 00
15 00
10 00
50 0
12 0 12 5 13 0 13 5 14 0 15 014 5 16 0 17 0 18 0
LD P E
O ct,LL D P E
mP E
Fo rce
g/ i nc h
T e mp eratu re (de grees C )
H ot T ack S tr engt h
Figure 14.6
29
Heat Sealing Parameters
Fig,14.7
Inc r eas i ng T emper atur e
H
e
a
t
-
S
e
a
l
S
t
r
e
n
g
t
h
H i gh bar
pr es s ur e
Medi um bar
pr es s ur e
30
foil
polyethylene
poly(ethylene terephthalate)
foil
sealing medium
printed paper
sealing medium
Retort pouch Aseptic box
sealing medium
printed polypropylene
metallized polypropylene
Snack food bag
saran-coated nylon
sealing medium (Surlyn)
Luncheon meat tray
Example Laminations
See Figures 14.13 & 14.14
31
printed polyethylene
polyethylene
Ethylene-vinyl alcohol
High oxygen barrier
polyethylene
poly(ethylene terephthalate)
sealing medium (vinyl)
overlacquer
Single-service lidding stock
printed foil
Example Laminations
See Figures 14.13,14.14
(For barrier applications
foil to the inside)
surface print
paper
polyethylene
sealing medium
foil
Basic food pouch laminate
32
Laminate
roll stock
High
barrier
insert
Finished
tube1
Injected molded tip
Laminated Collapsible Tube Construction
Formed body
Foil
Clear LDPE
paper
Sealing medium
Printed white PE
EAA
33
Vertical Form-Fill-Seal (VFFS)
Fig,14.2
Unwi n d
Prod u c t fl o w
Dr a w- d o w n b e l ts
L o n g i t u d i n a l s e a l i n g j a w
Cr o s s -s e a l i n g a n d c u t-o f f
Fo rm i n g
c o l l a r
CoF is critical!
34
VFFS Pouch Seals Compared
Fig,14.5
Fin seal Lap Seal
Seals inside surfaces
Uses more material
Don’t cover UPC!
Seals outside to inside
Both surfaces need
sealing medium
Use less material
35
Horizontal Form-Fill-Seal (HFFS)
Fig,14.3
U nw i n d
T e ns i on c on trol
Form i n g p l ow
T o p s ea l
C ut-o f f
O pe n po uc h
Fi l l er #1
Fi l l er #2
Fi l l er #3
C l os e p ou c h
S i d e s e al
36
Common HFFS Pouch Styles
Fig,14.5
Conventional pouch has three-side seal
Can be made into various stand-up designs
Some stand-up pouches are pre-made in a separate
operation
Three-side
sealed pouch
Gusseted
designs
37
Multi-Lane Form-Fill-Seal
Fig,14.4
V e rt i c a l h e a t s e a l s H o ri z o n t a l h e a t s e a l s
Prod u c t d i s p e n s e rs
Fo u r-s i d e d s e a l p o u c h e s
(s e p a ra te d )
38
Stand-Up Pouch Examples
39
Stand-Up Pouch Examples
40
Film Thickness Measurement
Inch Gauge Mil Micrometre
0.001inch = 100 gauge = 1 mil = 25 mm
0.0005 inch = 50 gauge = 1/2 mil = 13 mm
ISO metric notes,
,Micron” is a depreciated term for micrometre
one inch = 25.4 millimetres and
0.001 inch = 25.4 micrometres
41
Early Universal Barriers
PVDC is original high universal barrier polymers
EVOH laminated between high moisture barrier
polymers can also provide good universal barrier
But not high enough barrier for critical applications
Metallizing also produces a high universal barrier
But aluminum metallized films are not transparent
42
Recent Advances in Achieving Barrier
Monolayer polymers
poly(ethylene naphthalate) ($)
liquid crystal polymer ($$$)
Multilayered constructions
PET/PA/PET
PET/EVOH/PET
PET/MXD6/PET/ MXD6/PET
43
Recent Advances in Achieving Barrier
Interior coatings
SiOx (glass) coating (Glaskin)
AlOx aluminum oxide coating
carbon coating (DLC and Actis)
Exterior coatings and interior laminates
epoxy-amine coating (Sealica and Bairocade)
copolyester (Amosorb,interior layer)
Nanocomposites
extremely fine mineral additions
Flexible Packaging Laminates
Lesson 8
第 8课 软包装复合材料
2
Plasticating Extruder
Ex i t
p o rt
Gea r re d u c e r
V a ri a b l e spe e d mo to r
F e e d t h ro a t
F e e d h o p p e r
Ho p p e r th ro a t
Co o l i n g j a c k e t
Sc re w
He a t e r b a n d s
Fig,10.2
3
A dj us tabl e
D i e L i p s
E x tr us i on
D i e
A dj us tabl e P r es s ur e
( R es tr i c tor ) B ar
E x tr ude r
Cast Film and Sheet Extrusion
Fig.10.4
4
E x t ru de r # 1
E x t ru de r # 2
E x t ru de r # 3
M ate ri a l # 1
M ate ri a l # 2
M ate ri a l # 3
Three-Layer Coextrusion
Fig.10.9
5
Extrusion Cast Film Line Layout
E x t ruder
E x t rusi on d i e C hi l l ro l l
E dg e tri m me r
Ma teri al ro l l
Fig.10.5
6
Machine Direction Orientation
R ot a tion x 1 x 3x 2 X 4
F r om e xtr ud er
castin g r oll s
Fig.10.8
7
Ext rud er
C as ti ng Rol l s
Ann ea l i ng Z on e
Ext rus i on Di e
T e nt er C l i ps
Cross Direction Orientation
Fig.10.8
8
Bub b l e
Blo w -u p a i r i n l e t
Coo l i n g a i r Coo l i n g a i r
Pla s ti c fro m e x tru d e r
Die l i p a d j u s ti n g b o l ts
Die Bod y
Die c o re
Fro s t l i n e
Bub b l e c o n s ta n tl y p u l l e d u p
Blown-film Die Cross-Section
Fig.10.6
9
Three-layer Extrusion Blow Mold
Cut-away view
material 1
material 2
material 3
film bubble
10
Ex t ru d e r
Cir c u l a r
d i e
Ai r ri n g
In t e rn a l b u b b l e c o o l i n g
Pl a s ti c f i l m b u b b l e
Col l a p s i n g f ra m e
Upp e r n i p ro l l s
Sl i tt e r
Dua l ro l l
win d e r
Blown Film Line With Slitter
Fig.10.7
11
Blown Film Line Showing Die & Bubble
12
Aluminum Foil
Household foil is typically 17.5 mm (0.0007 inches)
Available in gauges as low as 7 mm (0.00028 inches)
Pin holing is present below 12 mm (0.0005 inches)
Foil is susceptible to flex cracking
Most foils are supported with plastic and/or paper
Unsupported foil used for some lid-stock & tablet
push-through packaging
13
Intact foil is a 100% barrier to all gases
Best deadfold properties
Easily punctured (tamper evidence)
Reflective of radiant heat
Conductive (induction sealing)
Decorative appeal,all reflective metallics are aluminum
Aluminum Foil Characteristics
14
Foil Packaging Applications
Unsupported foil,non-sealable
e.g,confection and cheese wraps
Unsupported foil,heat sealable
e.g,lidding stock,pharmaceutical tablet
backing material
Supported foil,non heat sealable
e.g,decorative wraps,label stock
Supported foil,heat sealable
e.g,high barrier pouches and sachets
lidding stock,retort pouches
15
Aluminum Vacuum Metallizing
Fig.14.1
V a cu u m l in e
Unwin d r o l l
A luminu m v a p o r
Cera mi c b o a t
Rewin d r o l l
A luminu m
wi r e Chill e d ro l l
16
Provides reflective metallic appearance
Improves moisture,aroma,light and oxygen barrier
Oxygen barrier improved,
up to fifty times for OPP,up to ten times for PET
Static dissipative applications
OPP,PET,& PA (nylon) most common packaging films
Aluminum Metallized Film
17
Why Laminate?
There is no perfect,universal packaging material
Laminates assemble materials with individually
desirable properties to create an optimum material
Laminate,A product made by bonding together
two or more materials
18
Mechanical properties
tensile strength stiffness
coefficient of friction use temperatures
elongation formability
Laminate Properties
Barrier properties as required
oxygen barrier essential oil barrier
water vapor barrier light barrier
19
Laminate Properties
Sealability
most flexible packaging is heat sealed
most heat seals are polyethylene based
other polymers used more critical applications
Aesthetic appearance
clarity
surface gloss
reflective metallics
20
Describing Packaging Laminate
Note,
Packaging laminate plies are always
listed from the outside to the inside
21
Gravure Coating
Fig,14.8
22
Wet Bond Laminator
Fig,14.10
23 Fig,14.11
Dry Bond Laminating
24
Solventless Laminating
Solventless laminating uses catalyzed or or two-part
reactive adhesives
25
Extrusion Laminating
Fig,14.9
E xt r u si o n d ie
C h i ll r o l l
S u b s t r a t e A
S u b s t r a t e B
S t r i p - o f f r o ll
P r e ssu r e
r o ll
N ip r o ll
E xt r u d a t e Th r e e p ly
la m in a t e
26
Hot Tack
The bond strength of the seal while still hot
Critical for most form-fill-seal machines
Determines how quickly product can be dropped
into a pouch
27
Common Heat- Seal Materials
cost
bond quality
ionomer (e.g,Surlyn,seals through contaminants )
acid copolymer (good foil bond,chemical resistance)
metallocene polyethylene (low temp,fast seal)
LLDPE (good hot tack,tough,wide seal temp.)
PE/EVA (soft film,low seal temperature)
medium-density polyethylene (stiffer,better barrier)
cast polypropylene (stands higher temperatures)
low-density polyethylene
Table 14.5
28
Source,M,Lutterotti,DuPont
Sealing Mediums Compared
30 00
25 00
20 00
15 00
10 00
50 0
12 0 12 5 13 0 13 5 14 0 15 014 5 16 0 17 0 18 0
LD P E
O ct,LL D P E
mP E
Fo rce
g/ i nc h
T e mp eratu re (de grees C )
H ot T ack S tr engt h
Figure 14.6
29
Heat Sealing Parameters
Fig,14.7
Inc r eas i ng T emper atur e
H
e
a
t
-
S
e
a
l
S
t
r
e
n
g
t
h
H i gh bar
pr es s ur e
Medi um bar
pr es s ur e
30
foil
polyethylene
poly(ethylene terephthalate)
foil
sealing medium
printed paper
sealing medium
Retort pouch Aseptic box
sealing medium
printed polypropylene
metallized polypropylene
Snack food bag
saran-coated nylon
sealing medium (Surlyn)
Luncheon meat tray
Example Laminations
See Figures 14.13 & 14.14
31
printed polyethylene
polyethylene
Ethylene-vinyl alcohol
High oxygen barrier
polyethylene
poly(ethylene terephthalate)
sealing medium (vinyl)
overlacquer
Single-service lidding stock
printed foil
Example Laminations
See Figures 14.13,14.14
(For barrier applications
foil to the inside)
surface print
paper
polyethylene
sealing medium
foil
Basic food pouch laminate
32
Laminate
roll stock
High
barrier
insert
Finished
tube1
Injected molded tip
Laminated Collapsible Tube Construction
Formed body
Foil
Clear LDPE
paper
Sealing medium
Printed white PE
EAA
33
Vertical Form-Fill-Seal (VFFS)
Fig,14.2
Unwi n d
Prod u c t fl o w
Dr a w- d o w n b e l ts
L o n g i t u d i n a l s e a l i n g j a w
Cr o s s -s e a l i n g a n d c u t-o f f
Fo rm i n g
c o l l a r
CoF is critical!
34
VFFS Pouch Seals Compared
Fig,14.5
Fin seal Lap Seal
Seals inside surfaces
Uses more material
Don’t cover UPC!
Seals outside to inside
Both surfaces need
sealing medium
Use less material
35
Horizontal Form-Fill-Seal (HFFS)
Fig,14.3
U nw i n d
T e ns i on c on trol
Form i n g p l ow
T o p s ea l
C ut-o f f
O pe n po uc h
Fi l l er #1
Fi l l er #2
Fi l l er #3
C l os e p ou c h
S i d e s e al
36
Common HFFS Pouch Styles
Fig,14.5
Conventional pouch has three-side seal
Can be made into various stand-up designs
Some stand-up pouches are pre-made in a separate
operation
Three-side
sealed pouch
Gusseted
designs
37
Multi-Lane Form-Fill-Seal
Fig,14.4
V e rt i c a l h e a t s e a l s H o ri z o n t a l h e a t s e a l s
Prod u c t d i s p e n s e rs
Fo u r-s i d e d s e a l p o u c h e s
(s e p a ra te d )
38
Stand-Up Pouch Examples
39
Stand-Up Pouch Examples
40
Film Thickness Measurement
Inch Gauge Mil Micrometre
0.001inch = 100 gauge = 1 mil = 25 mm
0.0005 inch = 50 gauge = 1/2 mil = 13 mm
ISO metric notes,
,Micron” is a depreciated term for micrometre
one inch = 25.4 millimetres and
0.001 inch = 25.4 micrometres
41
Early Universal Barriers
PVDC is original high universal barrier polymers
EVOH laminated between high moisture barrier
polymers can also provide good universal barrier
But not high enough barrier for critical applications
Metallizing also produces a high universal barrier
But aluminum metallized films are not transparent
42
Recent Advances in Achieving Barrier
Monolayer polymers
poly(ethylene naphthalate) ($)
liquid crystal polymer ($$$)
Multilayered constructions
PET/PA/PET
PET/EVOH/PET
PET/MXD6/PET/ MXD6/PET
43
Recent Advances in Achieving Barrier
Interior coatings
SiOx (glass) coating (Glaskin)
AlOx aluminum oxide coating
carbon coating (DLC and Actis)
Exterior coatings and interior laminates
epoxy-amine coating (Sealica and Bairocade)
copolyester (Amosorb,interior layer)
Nanocomposites
extremely fine mineral additions
