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Flashcards in Laminates Deck (18):
1

objectives of lamination

combine properties
mechanical
barriers
heat sealing
optical
printability
stretch
machinability

2

use of laminate to

long shelf life
high profit product
very sensitive product

3

method of lamination

adhesive lamination
extrusion coating
co-extrusion
vacuum metallization

4

adhesive lamination

adhesive applied to one web combined with other
solvent or water based type values with heat requirements, bond strength
it is cured = dried = because excess solvent cause delamination
coated web combined with uncoated using pressure/heat
process continues until laminate complete

5

extrusion coating

with PE, PP, PET, paper
advantages
- handling thin PE difficult
- Extrusion Temperature impregnate plastic onto paper
- cheap
- less pollution
need pretreatment for foil
extradite acts as a glue

6

co-extrusion

two or more extrusion feeders
low cost
less delamination
flexiblility

7

vacuum metallization

metallized films
- reflectance, metallic look, attractive
- tough
- converts mw NRJ into radiant heat = susceptor
good barrier to moisture, flavor, light, gaz
pretreatment before vacuum = mechanical treatment = high voltage and high frequency and corona generates film surface by introducing polar groups
metal is vaporized in vacuum chamber
coated with varnish to seal, smooth surface

8

functionality of laminate layer

print/abraison resistance
mechanical structure
barrier
heat sealability
product compatibility

9

example juice box

PE = outer protection
printed paper
PE = improves puncture resistance of foil
foil = excellent barrier to moisture and flavor
PE = improves foil heat sealibility

10

heat seal

depends on melt T, machine P, contact time
desirable = low melt T, strong seal, low cost
common heat seal = LDPE (low T fast seal), EVA (ethylene vinyl acetate), Ionomer like surlyn (seals through crumbs grease)

11

barriers

nylon = outer often = poor water, high gaz barrier
LDPE = heat sealing barrier
PVDC = excellent water/gaz barrier
LDPE + ionomer = coextruded heat sealing layer
OP = breathable layer = high water barrier low gaz barrier

12

types of composite cans

convolute wind
spiral wind
linear draw
single wrap

13

design variations

shape
size
paperboard and body layers
opening and closing systems
label

14

function of paper layer in can body

strength
structure
printability
Kraft
recylced

15

function of PE layer in can body

protect paper form moisture, tear, scratches
heat seal other layers
barrier to moisture (low gaz barrier)

16

function of foil layer in can body

barrier to light, moisture, gaz
printable

17

emerging tech

sorbents incorporated into liner layers

18

what to consider for opening/closing systems

product characteristics
ease of use
protection needed
dispensing needs
hermetic needs
reclosability needs