Guidance for the identification of polymers in multilayer films used in food contact materials : user guide of selected practices to determine the nature of layers.
Date: 2017-04-27
Institutions: Joint Research Centre
Subjects: food safety, packaging product, polymer, product safety, research method, research report, user guide

Guidance for the identification of 
polymers in multilayer films used 
in food contact materials   

User guide of selected 
practices to determine 
the nature of layers 

Anja Mieth, Eddo Hoekstra, Catherine 
Simoneau 

2016  

1 

EUR 27816 EN 

 
 
 
 
 
 
 
This publication is a Technical report by the Joint Research Centre, the European Commission’s in-house science 
service. It aims to provide evidence-based scientific support to the European policy-making process. The scientific 
output expressed does not imply a policy position of the European Commission. Neither the European 
Commission nor any person acting on behalf of the Commission is responsible for the use which might be made 
of this publication. 

Contact information 
Catherine Simoneau 
Address: Joint Research Centre, TP 260 
E-mail: JRC-FCM@ec.europa.eu  

JRC Science Hub 
https://ec.europa.eu/jrc 

JRC100835 

EUR  27816 EN 

ISBN 978-92-79-57561-7 (PDF) 

ISSN 1831-9424 (online) 

doi:10.2788/10593 (online) 

© European Union, 2016 

Reproduction is authorised provided the source is acknowledged. 

All images © European Union 2016 

How to cite:  
Anja Mieth, Eddo Hoekstra, Catherine Simoneau - Guidance for the identification of polymers in multilayer films 
used  in  food contact materials:  User guide  of  selected practices to determine the nature of  layers;  EUR  27816 
EN; doi:10.2788/10593 

2 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Table of contents  

Abstract ............................................................................................................................. 4 

1. Introduction ................................................................................................................ 4 

2. Terms and definitions ................................................................................................... 5 

3 Analysing the composition of a multilayer plastic film: Separation and identification of layers . 5 

3.1 Scope .................................................................................................................... 5 

3.2 Materials and reagents ............................................................................................. 6 

3.2.1 Organic solvents (all of reagent grade) ................................................................. 6 

3.2.2 Organic and inorganic acids ................................................................................ 6 

3.2.3 Reagents and materials for analytical tests ........................................................... 6 

3.2.4 Other materials ................................................................................................. 6 

3.3 Equipment .............................................................................................................. 6 

3.3.1 Microtome and polarization microscope ................................................................ 6 

3.3.2 ATR-FTIR system ............................................................................................... 6 

3.3.3 DSC system ...................................................................................................... 6 

3.3.4 Glassware and other laboratory equipment ........................................................... 6 

3.4 General composition of multilayer packaging films ....................................................... 7 

3.4.1 Plastic polymers ................................................................................................ 7 

3.4.2 Aluminium foil ................................................................................................... 8 

3.4.3 Bonding of the different layers ............................................................................ 8 

3.4.4 Coatings/lacquers ............................................................................................ 10 

3.4.5 Non-food contact printings ............................................................................... 11 

3.4.6 Direct food contact printings ............................................................................. 12 

3.5 Analysis of the composition of a Multilayer film ......................................................... 12 

3.5.1 Microtome sectioning and microscopy ................................................................ 12 

3.5.2 Identification of food contact layer and outside layer by ATR-FTIR ......................... 13 

3.5.3 Separation of layers ......................................................................................... 13 

3.5.3.1 Selection of solvents .................................................................................. 13 

3.5.3.2 Immersing the sample in solvent ................................................................. 15 

3.5.4 Identification of the layers peeled off and laid open (ATR-FTIR  spectroscopy) ........ 16 

3.5.5 Specification of layers with DSC ........................................................................ 19 

3.5.6 Special analytical tests for the identification of printing inks and coatings ............... 20 

3.6 Examples ............................................................................................................. 21 

References ....................................................................................................................... 34 

Annex 1: Example of protocol for operating a rotary microtome .............................................. 37 

Annex 2: Example of protocol for microscopy of microtome cross-sections ............................... 50 

Annex 3: Example of protocol for handling/maintenance of an ATR-FTIR spectrometer .............. 67 

3 

 
 
 
 
 
 
Abstract  

This guidance describes how to  characterize the composition of a multilayer plastic film 
for food packaging, with respect to the consecutive order of the layers and their identity. 
It  provides  background  information  on  the  general  composition  of  multilayer  plastic 
packaging and it illustrates in detail the separation of layers for some examples. It also 
provides  in  annexes  additional  information  related  to  the  use  of  a  microtome  and  of 
optical microscopy using one common instrument for illustrative purposes.  

1. Introduction  

Being  able  to  identify  the  composition  of  a  packaging  film  is  essential  to  confirm  the 
correctness of specifications given in the Declaration of Compliance that accompanies all 
food  contact materials made of plastic (see  EU 10/2011 Art. 15 and Annex  IV (3) [1]). 
Furthermore,  each  type  of  polymer,  printing,  coating  and  adhesive  contains  typical 
additives  and  monomers  or  oligomers  with  a  potential  for  migration, while  at  the  same 
time  certain  layers  can  act  as  functional  barriers  for  particular  migrants.  Therefore, 
knowing  the  composition  of  a  multilayer  film  enables  laboratories  to  predict  which 
migrants  can  be  expected  from  the  packaging  film  and  thus  also  helps  to  check  the 
plausibility of obtained migration results. 

A PT was organised in 2013 which for the first time aimed at estimating performance of 
qualitative  analysis.  The  aim  of  the  exercise  was  to  test  the  laboratories'  ability  to 
identify unknown plastics materials via quick screening tools. The results demonstrated a 
spread  and  some  level  of  difficulty  for  laboratories  to  identifying  particular  multilayer 
materials.  A  follow  up  was  organised  in  2014  specifically  for  multilayers,  in  order  to 
ensure improved laboratory performance.  

Considering  there  are  no  reference  methods  and  the  novelty  to  tackle  assessments  of 
qualitative  nature,  EU-RL  FCM  produced  a  number  of  methods  descriptions  to  assist 
NRLs in doing this type of analysis. The descriptions have been integrated in the present 
guidelines.  

4 

 
 
 
 
 
 
 
 
 
 
 
 
2. Terms and definitions 

AlOx 
ATR 
BOPP 
CN 
DMSO   
DSC 
EAA 
EB 
EMA 
EVA 
EVOH 
FTIR 
HDPE 
ionomers 
LDPE 
LLDPE   
PA 
PA6 
PA6/66 PA  
PA6/MXD6 
PA66 
PAMXD6 
PC 
PE 
PEN 
PET 
PET-G   
PMMA   
PP 
PS 
PTFE 
PUR 
PVC 
PVDC 
SiOx 
UV 

aluminium oxide 
attenuated total reflection 
biaxially-oriented polypropylene 
cellulose nitrate (nitrocellulose) 
dimethyl sulfoxide 
differential scanning calorimetry 
ethylene acrylic acid copolymer 
electron beam 
ethylene methyl acrylate copolymer 
ethylene vinyl acetate copolymer 
ethylene vinyl alcohol copolymer 
Fourier Transform Infrared 
high density polyethylene 
EAA or EMA neutralised with cations (e.g. Na+, Zn2+, Li+) 
low density polyethylene 
linear low density polyethylene 
polyamide 
PA homopolymer made from caprolactam 
copolymer made from caprolactam, hexamethylenediamine and adipinic acid 
PA copolymer made from caprolactam, m-xylylenediamine and adipinic acid 
PA homopolymer made from hexamethylenediamine and adipinic acid 
PA homopolymer made from caprolactam, m-xylylenediamine and adipinic acid 
polycarbonate 
polyethylene 
polyethylene naphthalate 
polyethylene terephthalate 
glycol-modified polyethylene terephthalate 
polymethyl methacrylate 
polypropylene 
polystyrene 
polytetrafluorethylene 
polyurethane 
polyvinylchloride 
polyvinylidene chloride 
silicon oxide 
ultraviolet. 

3  Analysing  the  composition  of  a  multilayer  plastic  film: 
Separation and identification of layers  

3.1 Scope  

This procedure describes how to characterize the composition of a multilayer plastic film 
for  food  packaging,  meaning  the  consecutive  order  of  the  layers  and  their  identity.  It 
provides  background  information  on  the  general  composition  of  multilayer  plastic 
packaging and it illustrates in detail the separation of layers for some examples. 

5 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3.2 Materials and reagents 

3.2.1 Organic solvents (all of reagent grade) 

Acetone, butyl acetate, carbon disulfide, chloroform, cyclohexanone, cycloheptanone, di-
n-butyl  sulfoxide,  N,N-dimethylacetamide,  N,N-dimethylformamide,  dimethyl  sulfoxide, 
ethyl  acetate,  methylene  chloride,  methyl  ethyl  ketone,  tetrahydrofuran,  toluene,  p-
xylene 

3.2.2 Organic and inorganic acids 

  Formic acid, reagent grade, ≥95% 
  Hydrochloric acid, reagent grade, 37% 
  Sulfuric acid, reagent grade, 95-98 % 

3.2.3 Reagents and materials for analytical tests 

  Sodium hydroxide, reagent grade, ≥98% 
  Diphenylamine 
  Copper wire 

3.2.4 Other materials 

  Cotton sticks 
  Paper towels 
  Glass beads 

3.3 Equipment 

3.3.1 Microtome and polarization microscope 

  Boeckeler S300 rotary microtome 
  Zeiss Axioskop 2 MAT, equipped with AxioCam MRc 

3.3.2 ATR-FTIR system 

  Perkin Elmer Spectrum One FT-IR Spectrometer 
  Perkin Elmer Universal ATR Sampling Accessory 
  Software: Spectrum Version 6.3.1, Perkin Elmer 

3.3.3 DSC system 

  TA Instruments DSC Q100 
  TA Instruments DSC Refrigerated Cooling System 
  Software: Advantage for Q Series Version 2.5, Thermal Advantage Release 4.7.3 

3.3.4 Glassware and other laboratory equipment 

  25 mL and 50 mL glass beakers 
  Watch glasses, diameter 4-5 cm 
  Glass test tubes 
  Tweezers 
  Scissors 
  Heating plate 
  Bunsen burner 

6 

 
 
 
 
 
3.4 General composition of multilayer packaging films 

3.4.1 Plastic polymers 

Several  plastic  polymers,  copolymers  and  blends  are  used  for  the  production  of 
multilayers.  The  most  important  polymers  are  polyethylene  (LDPE,  HDPE,  LLDPE), 
polypropylene,  polyamide  (PA6,  PA6/66,  PA6/MXD6),  polyethylene  terephthalate, 
polystyrene,  ethylene  vinyl  alcohol,  polyvinylidene  chloride,  ethylene  vinyl  acetate  and 
polycarbonate  ([2]-[14]).  Polyvinyl  chloride  may  also  be  used  as  a  plastic  layer  in 
multilayer  food  packaging  ([1]).  Table  1  lists  the  most  common  polymers  in  multilayer 
packaging materials, their functions in the packaging and some applications. 

Table 1 Plastic polymers used in multilayer food packaging ([1], [4], [5], [6], [8], [9], [18], [26], [27], [28], 

[35]) 

Plastic polymer 

Functions in multilayers 

Applications 

Polyethylene 
(PE) 

Polypropylene 
(PP) 

Polyamide 
(PA) 

heat-sealable food contact layer 
moisture barrier 
can be combined with gas/aroma barriers 
(e.g. PA, EVOH) 

moisture barrier 
to provide mechanical strength 
can be coated with heat seal coatings 
(PVDC, acrylate) 
can be combined with gas/aroma barriers 
(e.g. PVDC coatings, PA, EVOH) 

gas/aroma barrier 
to provide mechanical strength 
heat resistance 
can be used as outside layer of a heat seal 
film → film will not stick to the sealing bar 
surface 

Polyethylene 
terephthalate 
(PET) 

gas/aroma barrier 
moisture barrier 
to provide mechanical strength 
heat resistance 

Polystyrene 
(PS) 

Ethylene vinyl 
alcohol 
(EVOH) 

Polyvinylidene 
chloride 
(PVDC) 

gas permeability 
printability 
can be combined with gas/aroma barriers 
(coextruded or laminated) → commercially 
available structures: e.g. PS/PVDC/PS, 
PS/PVDC/PE, PS/EVOH/PE, PS/EVOH/PP 

oxygen barrier 
needs to be protected from moisture → 
often sandwiched (coextruded) between 
PE or PP, in some applications also 
sandwiched between PET, PA or PS 

gas/aroma and/or moisture barrier 
to protect the surface from scratches and 
abrasion 
heat-sealable food contact layer 
often copolymers of vinylidene chloride 
and ester-type monomers (e.g. ethyl 
acrylate) 

breathable packaging for fresh 
produce (LDPE, HDPE) 
carton liners (LLDPE) 

modified atmosphere packaging 
thermoformed containers for 
microwavable packaging, hot-
filled packaging 

boil-in-bag packaging 
thermoformed packaging 

plastic bottles for carbonated 
softdrinks, meat and cheese 
packaging, snack food wrapper 
boil-in-bag, sterilisable pouches, 
ovenware containers 

breathable packaging for fresh 
produce (e.g. fresh-meat 
packaging) 
printable outside layers 

modified atmosphere packaging 
packing of oxygen-sensitive 
food 

modified atmosphere packaging 
applied as coating or coextruded 
film 

7 

 
 
 
 
Plastic polymer 

Functions in multilayers 

Applications 

Ethylene vinyl 
acetate 
(EVA) 

moisture barrier 
adhesion layer (tie layer) for co-extrusion 
of polar (e.g. PA, PET-G) and non-polar 
(e.g. PE) polymers 
heat-sealable food contact layer; heat-
sealable extrusion coatings on PET or 
BOPP films 

Polycarbonate 
(PC) 

heat resistance 
mechanical strength 
moisture barrier 

Polyvinylchloride 
(PVC) 

gas/aroma barrier 
mechanical strength 

Polyethylene 
naphthalate 
(PEN) 

Glycol modified 
polyethylene 
terephthalate 
(PET-G) 

Ethylene acrylic 
acid 
(EAA) 

gas/aroma and moisture barrier 
heat resistance 

heat-sealable food contact layer 

extrusion coating tie layer between 
aluminium foil and other polymers 
heat-sealable food contact layer 

modified atmosphere packaging 
applied as coating or coextruded 
film 

microwavable packaging, hot-
filled packaging 
modified atmosphere packaging 
barriers for fruit juice cartons 

fresh food packaging (e.g. 
PVC/PE films) 
modified atmosphere packaging 
(e.g. PVC/EVOH/PE films) 

for hot refills, rewashing, reuse 
beverage bottles (e.g. beer) 

3.4.2 Aluminium foil 

Many  packaging  materials,  especially  for  high  value  foods  (e.g.  dried  soups,  herbs, 
spices),  contain  a  layer  of  aluminium  foil  as  it  is  an  effective  barrier  against  moisture, 
air, odours and UV light [26]. 

3.4.3 Bonding of the different layers 

Multilayer  films  can  be  prepared  by  co-extrusion  or  by  lamination.  Co-extrusion  can  be 
performed as blown film extrusion or cast extrusion [14]. In both cases, granules of the 
different  plastics  are  melted  separately  and  the  melts  are  brought  together  in  the 
extruder. The  combined plastics then are extruded as a single product in which the co-
extruded layers bond directly to each other. 

In order to achieve bonding of two molten polymer layers during co-extrusion, it can be 
necessary  to  apply  a  third  polymer  ("extrudable  adhesive")  in  between.  For  example, 
anhydride-modified  polyethylene  or  anhydride-modified  EVA  can  act  as  an  extrudable 
adhesive in the co-extrusion of PE and PA [9]. 

In  contrast  to  co-extrusion,  lamination  combines  two  or  more  plastic  or  non-plastic 
materials  (e.g.  aluminium  foil)  in  web-form  by  applying  a  certain  type  of  adhesive 
between  them.  Three  main  principles  of  lamination  can  be  distinguished.  These  are 
extrusion  lamination,  adhesive  lamination  and  wax/hot  melt  lamination.  In  extrusion 
lamination,  a  molten  polymer  (e.g.  LDPE)  is  applied  to  one  of  the  webs  and  a  second 
web  is  fed  from  the  top.  In  adhesive  lamination,  an  adhesive  is  applied  instead.  These 
can  be  solvent  based  adhesives  ("dry  bond  lamination"),  one-  or  two-component  water 

8 

 
 
 
 
 
 
 
 
based  adhesives  ("wet-bond  adhesion"),  two-component  solid  adhesives  ("solventless 
lamination"), UV-curing or electron beam-curing adhesives ([14], [25]). 

In  wax/hot  melt  lamination,  a  layer  of  molten  wax  or  hot  melt  is  applied  between  two 
webs and then cooled to bond them together. The wax remains heat sensitive. Therefore 
this technique is not suitable if the packaging will be heat-sealed afterwards or filled very 
hot ([9], [14]). 

Table 2 lists some of the most important adhesives for the different types of lamination 
and their applications. 

Table 2 Adhesives and waxes/hot melts used for lamination ([9], [14], [39], [40]) 

Type of 
lamination 

Adhesive 

extrusion 
lamination 

LDPE 

EVA 

acid-containing adhesives: 
EAA or EMA 
ionomers 
terpolymers of ethylene, acid and 
acrylate (e.g. methyl acrylate or 
isobutyl acrylate) 

anhydride modified polyolefins: 
terpolymers of ethylene, maleic 
anhydride and acrylates (e.g. ethyl 
acrylate, butyl acrylate) 

Examples of selected applications 

multilayer-multimaterial packaging 
(combination of plastic or aluminium 
foil with paper or paperboard → e.g. 
fruit juice cartons) 

bonding PE to PVC 

used to bond with aluminium foil 

dry bond 
lamination 

solvent based PUR adhesives 

flexible packaging → lamination of 
plastic films (bags, pouches, wraps for 
snack food, meat and cheese packs, 
boil-in-bag food pouches) 

wet-bond 
adhesion 

poly(vinyl acetate) emulsion (or 
coploymers of vinyl acetate and 
ethylene or acrylic esters) 

crosslinking acrylic-vinyl acetate 
copolymer emulsions  

acrylic emulsion pressure-sensitive 
adhesives 

polyurethane dispersions 

snack packages (e.g. potato chip bags) 

pressure-sensitive labels 

lamination of plastic films in medium-
performance flexible packaging where 
some chemical resistance is required 

UV-curing 

acrylics and acrylates, epoxies, 
polyurethanes, polyesters, silicones, 
and vinyl and vinyl esters 

flexible plastic packaging (at least one 
of the webs must be transparent to 
allow UV penetration) 

EB-curing 

see UV-curable adhesives 

solventless 
lamination 

hot-melt 
lamination 

polyurethanes 

EVA 

ethylene-butyl acrylate 

9 

 
 
 
 
 
 
 
 
 
 
 
 
Type of 
lamination 

Adhesive 

LDPE 

block copolymers of styrene, butadiene 
or isoprene 

moisture curing PUR hot melts 

Examples of selected applications 

for paper bonding constructions, case 
seaming, bag seaming and sealing 

hot-melt pressure-sensitive adhesives 
for tapes and labels, attachment of PE-
base cups to polyester soft-drink 
bottles, sealing of film-laminated 
frozen-food cartons 

3.4.4 Coatings/lacquers 

Coatings or lacquers can be applied to the inside (food contact layer), outside (non-food 
contact  layer)  or  in  between  layers  to  enhance  the  appearance  or  alter  the  physical 
properties of the packaging [17]. An overview of the most common types of coatings is 
given in Table 3. 

Table 3 Coatings used in multilayer plastic food packaging ([8], [14], [16], [17], [26], [31]). *Ionomers: EAA 

or EMA neutralised with cations (e.g. Na+, Zn2+, Li+) 

Type of 
coating 

Purpose 

protective 
coatings 

to protect the surface from mechanical 
damage 

heat-seal 
coatings 

primers 

cold seal 
coatings 

release 
lacquers 

antimists 

to allow heat sealability for non-sealable 
materials (e.g. flexible aluminium lids for 
yoghurt containers, polypropylene) 

to improve the bond between a substrate 
and an otherwise incompatible coating 

coatings that can be sealed self-to-self 
using just pressure (e.g. for flow-wrapping 
heat-sensitive products like chocolate or 
ice cream) 

applied to the opposite surface of a plastic 
film that is coated with coldseal to prevent 
sticking and to promote easy unwinding 
from the reel 

to prevent formation of condensate 
droplets/fogging on the food contact side 
(e.g. in fresh salad packaging) 

Substances in use 

nitrocellulose coatings, epoxy resins, 
reactive polyurethane systems, 
ionomers 

EAA, EVA, PVDC, PMMA, ionomers* 

polyethyleneimines, EAA 
dispersions, reactive polyethylene 
amines 

blends of acrylic resins and latex; 
synthetic rubber 

PA-based coatings 

PVDC coatings 

gloss/matt 
coatings 

to alter the visual perception of parts of 
the design 

PVDC, PMMA, nitrocellulose coatings 

gas and 
moisture 
barrier 

UV light 
barrier 

barrier to gases/odours/flavours and 
moisture 

PVDC, PMMA, SiOx, AlOx, aluminium 
vapour coating 

barrier to UV light 

aluminium vapour coating 

10 

 
 
 
 
 
 
 
3.4.5 Non-food contact printings 

Parts  of  the  sample  may  also  be  covered  with printings.  A  printing  can  be  applied  as  a 
surface printing on the outside (i.e. non-food contact side) of the multilayer packaging or 
as a reverse printing where it is trapped between two layers of the multilayer packaging 
([25],  [29]).  In  reverse  printing,  the  printing is  usually  applied  to  the  inside  surface  of 
the outermost plastic layer of the packaging ([25]) (see Figure 1). This way, the printing 
is best protected against mechanical damage (scratching, rubbing) and moisture, as well 
as  set-off  (i.e.  transfer  of  printing  ink  components  to  the  food  contact  layer  when  the 
packaging film is stored in staples or rolled) ([29]). 

Figure 1 Laminate with reverse printing (PA/print//PURPE) after boiling in ethyl acetate for 2 min 

To  protect  surface  printings  (e.g.  improve  rub  resistance)  and  to  provide  gloss  or  matt 
effects,  overprint  coatings  can  be  applied.  They  have  the  same  composition  as  the 
corresponding inks but do not contain pigments [15]. 

An  overview  on  the  main  compositions  of  the  most  commonly  used  ink  systems  is 
provided in Table 4. 

Table 4 Printing ink systems for non-food contact applications ([16], [19], [20], [21], [22]) 

Printing 
ink 
system 

Principle composition 

surface printing inks 

solvent-
based inks 

UV-curing 
inks (free 
radical 
curing) 

pigments 
binders: nitrocellulose, maleic resin, polyvinyl butyral, polyamide, polyurethane 
solvents: alcohols (ethanol, isopropanol), esters (ethyl acetate, isopropyl acetate), 
ethoxypropanol 
additives: plasticisers, slip additives (lubricants), adhesion promoters 

Pigments 
vehicles: 
oligomers: epoxy acrylates, polyester acrylates, polyether acrylates, urethane 
acrylates;  
monomers/reactive diluents: di-, tri-, tetrafunctional acrylates 
photoinitiators 
additives: waxes (PE/PTFE waxes), silicone oils, stabilisers 

cationic 
UV-curing 
inks 

pigments 
cationic photoinitiators: triarylsulphonium salts, diaryliodonium salts 
vehicles: diepoxide compounds and vinyl ethers 
additives 

electron 
beam-
curing inks 

pigments 
vehicles: 
oligomers: epoxy acrylates, polyester acrylates, polyether acrylates, urethane 
acrylates 

11 

 
 
 
 
 
 
Printing 
ink 
system 

Principle composition 

monomers/reactive diluents: di-, tri-, tetrafunctional acrylates 
additives 

water-
based inks 

pigments 
binders: styrene-acrylic co-polymers, acrylic co-polymers, maleic resins 
solvents: water, isopropanol, glycol ether, propylene glycol 
additives: amines, biocides, defoamers, wetting agents, waxes (PE, PTFE), slip 
agents 

Reverse printing inks 

solvent-
based inks 

pigments 
binders: vinyl resins, polyurethane, nitrocellulose, polyamide 
solvents: alcohols (ethanol, isopropanol), esters (ethyl acetate, isopropyl acetate), 
ethoxypropanol 
additives 

water-
based inks 

pigments 
binder: acrylic resin 
solvents: water 
additives 

3.4.6 Direct food contact printings 

For  promotional  reasons  (e.g.  special  campaigns),  sometimes  also  parts  of  the  food 
contact  layer  may  be  printed  (see  Figure  2).  For  this  purpose,  special  "direct  food 
contact  printing  inks"  are  used.  These  are  usually  pigmented  coatings  based  on  vinyl 
resins or modified cellulose ([16], [23], [24]). 

Figure 2 Chocolate packaging with printing on the food contact layer 

3.5 Analysis of the composition of a Multilayer film 

3.5.1 Microtome sectioning and microscopy 

It  is  recommended  to  prepare  a  microtome  section  (usually  of  5  µm  thickness)  of  the 
sample first and investigate it using a transmitted light microscope with polarized light. 
This will allow you to see  of how many layers  the sample consists  of  and whether they 
are  co-extruded  or  laminated.  Adhesives  in  laminated  samples  are  visible  in  the 
microtome section as thin layers of about 1-3 µm thickness between the polymer films. 

The coloration of the different layers in polarized light also gives a first idea about their 
identity.  Transparent  polyamide  layers  may  turn  green  in  polarized  light  and 
polyethylene terephthalate layers may appear in rainbow colours, while polyethylene or 
polypropylene remain colourless (see Figure 3). 

12 

 
 
 
 
 
 
 
Figure 3 Microtome sections of multilayer plastic laminates in polarised light 

3.5.2 Identification of food contact layer and outside layer by ATR-FTIR 

To identify the food contact layer (inside) and the outermost non-food contact (outside) 
layer of the sample, ATR-FTIR spectra of the inside and outside of the multilayer film are 
recorded. 

ATR-FTIR settings:  spectral range: 

4000-600 cm-1 

number of scans: 

4 

background:   

air (4 scans, 4000-600 cm-1) 

resolution: 

4 cm-1 

The  spectra  are  identified  by  comparison  to  the  spectra  database,  other  available 
standard spectra and the information provided in section 0 Table 8. 

3.5.3 Separation of layers 

The  separation  of  the  different  layers  can  be  achieved  by  taking  advantage  of  their 
different solubility properties. Having identified the food contact layer and the outermost 
layer (coating, printing ink or polymer film), a proper solvent or acid can be selected to 
dissolve  and  remove  these  outer  layers.  Alternatively,  it  is  possible  to  split  laminated 
layers  by  dissolving  the  adhesive  in  between  and  to  split  samples  that  contain  an 
aluminium layer by dissolving the aluminium. 

3.5.3.1 Selection of solvents 

Solvents for plastic polymers 

An  overview  about  the  solubility  of  the  most  common  plastic  polymers  used  for  the 
production of flexible packaging is given in Table 5. 

Table 5 Solvents and acids suitable to dissolve plastic polymers ([32], [33], [34]) 

Polymer/coating 

Soluble/decomposed in 

Polyethylene (PE) 

boiling p-xylene, boiling toluene, boiling dimethyl sulfoxide 

Polypropylene (PP) 

boiling toluene, boiling dimethyl sulfoxide 

Ethylene vinyl alcohol (EVOH) 

boiling N,N-dimethylformamide, hot concentrated sulfuric acid (turns 
black) 

13 

 
 
 
 
 
 
 
 
Polymer/coating 

Soluble/decomposed in 

Polyamide (PA) 

Polyethylene terephthalate 
(PET) 

Polystyrene (PS) 

hot concentrated formic acid, 37% hydrochloric acid, hot concentrated 
sulfuric acid (96 w%), boiling N,N-dimethylformamide 

boiling N,N-dimethylformamide (swells), hot concentrated sulfuric acid 

toluene, chloroform, cyclohexanone, butyl acetate, carbon disulfide, 
acetone, methylene chloride, ethyl acetate, boiling N,N-
dimethylformamide*, hot concentrated sulfuric acid (96 w%) (turns 
black) 

Polyvinylchloride (PVC) 

tetrahydrofuran, cyclohexanone, N,N-dimethylformamide, methyl ethyl 
ketone 

Polyvinylidene chloride (PVDC) 

boiling xylene, boiling N,N-dimethylacetamide, boiling cycloheptanone, 
di-n-butyl sulfoxide 

Polycarbonate (PC) 

methylene chloride, boiling N,N-dimethylformamide*, boiling 
dimethylsulfoxide*, hot concentrated sulfuric acid (96 w%) (turns 
black), acetone (swells), boiling toluene (swells) 

Ethylene vinyl acetate (EVA) 

toluene 

*requires strong heating and long time 

Solvents for adhesives in laminated samples (PUR adhesives, Polyester acrylates) 

Most  commonly  used  adhesives  in  the  manufacturing  of  flexible  food  packaging  are 
polyurethane (PUR) and acrylic or acrylate based adhesives. PUR adhesives can be easily 
dissolved in formic acid. Note that this procedure might also dissolve possible polyamide 
layers  and  others  soluble  in  formic  acid.  An  alternative  can  be  to  use  ethyl  acetate  or 
other suitable solvents instead (see Table 6).  

Note that all samples which contain an aluminium foil or an aluminium vapour coating as 
well as reverse printed samples are somehow laminated to bond the aluminium layer or 
reverse  printed  film,  respectively,  to  the  other  plastic  layers.  In  conclusion,  one  can 
always try to immerse any sample containing an aluminium layer or any reverse printed 
sample  in  formic  acid  or  ethyl  acetate  (or  other  suitable  solvents)  to  dissolve  the 
adhesive layers (see Figure 4). 

Figure  4  Sample  (PET/print//PURAl  foil//PURPE)  before  and  after  boiling  in  HCOOH  for  5  min.  Resulting  3 

separated layers: PET/print, Al foil, PE (top and bottom view shown) 

Table 6 Solvents and acids suitable to dissolve adhesive ([32], [33]) 

Polymer/coating 

Soluble/decomposed in 

Polyurethane (PUR) 

formic acid, methylene chloride (swells), acetone (swells), ethyl acetate 
(swells) 

Polyacrylates 

boiling xylene, toluene, methylene chloride, acetone, ethyl acetate 

14 

 
 
 
 
 
 
 
 
Dissolving aluminium foil or aluminium vapour coatings 

An aluminium foil or an aluminium vapour coating (i.e. a thin aluminium layer applied by 
thermal  evaporation)  itself  can  be  dissolved  by  immersion  in  concentrated  hydrochloric 
acid (37 % w/w). If the complete sample is immersed, the sample will split in two parts, 
the one above and the one below the aluminium layer (see Figure 5). 

Figure  5  Sample  with  an  inner  aluminium  foil  before  and  after  boiling  in  conc.  HCl  for  4  min  (Al  is  partly 

dissolved) and 5 min (Al is completely dissolved) 

Removal of printings and coatings 

Ink films and coatings often can be wiped off with a paper towel or cotton stick soaked in 
a suitable solvent. For example, acrylate and nitrocellulose coatings usually can be wiped 
off  with  ethyl  acetate.  If  this  is  not  successful,  the  sample  can  be  immersed  in  solvent 
and,  if  necessary,  heated  until  the  coating  is  completely  dissolved  (NOTE:  sometimes 
additional rubbing with a paper towel is required). 

An overview about suitable solvents for the most common coatings and printing ink films 
is provided in Table 7. 

Table 7 Solvents and acids suitable to dissolve binders of printing inks and coatings ([32], [33], [34]) 

Polymer/coating 

Soluble/decomposed in 

Polyvinylidene chloride (PVDC) 

boiling xylene, boiling N,N-dimethylacetamide, boiling 
cycloheptanone, di-n-butyl sulfoxide 

Ethylene vinyl acetate (EVA) 

toluene 

Nitrocellulose (CN) 

ethyl acetate, acetone 

Polyacrylates 

boiling xylene, toluene, methylene chloride, acetone, ethyl acetate 

Polymethyl methacrylate (PMMA) 

toluene, methylene chloride, acetone, ethyl acetate 

Polyurethane (PUR) 

formic acid, methylene chloride (swells), acetone (swells), ethyl 
acetate (swells) 

Aluminium metallisation 

37% hydrochloric acid 

3.5.3.2 Immersing the sample in solvent 

Cut  a  sample  piece  of  about  1  cm  x  3  cm.  It  should  be  of  asymmetric  shape  (e.g. 
trapezoid) to distinguish between the inner and outer side of the multilayer (and later on 
the layers peeled off) (see Figure 6). 

15 

 
 
 
 
 
 
 
 
 
Outer side 

(non-food contact) 

Figure 6 Sample preparation 

Inner side 
(food conact) 

Approximately 5 to 10 mL of solvent or acid (selected according to 0) are filled into a 25 
or 50 mL glass beaker. To prevent boiling retardation later on, add 2-3 glass beads. The 
sample  piece  is  added  (use  tweezers!)  and  the  beaker  is  covered  with  a  watch  glass. 
Never put more than 1 sample piece into the beaker at the same time. Otherwise  there 
is a risk to lose track of which sample eventually split off layers belong. 

The  beaker  is  placed  on  a  hot  plate  and  heated  carefully  to  make  the  solvent  boil. 
Depending  on  the  type  of  plastic,  it  may  take  up  to  10-15  min  until  the  respective 
sample layer is dissolved completely in the boiling solvent. However, often it is useful to 
immerse the sample only for a short time until parts of the respective layer are dissolved 
and then to tear or peel off the upper layer. Therefore, check every 1-2 minutes whether 
parts  of  the  sample  are  already  swollen  or  dissolved  (especially  at  the  edges  of  the 
sample  piece).  If  so,  take  out  the  sample  with  a  pair  of  tweezers,  rinse  it  with  a  non-
toxic  solvent  (e.g.  ethanol)  or  distilled  water  to  remove  adhering  solvent  and  acid, 
respectively,  dry  it  with  a  paper  towel  and  then  try  to  peel  off  the  upper  layer  using 
some  tweezers.  Do  not  forget  to  remove  the  beaker  from  the  hot  plate  when  you  are 
finished. Heating can also be performed in glass test tubes using a Bunsen burner. This 
process is faster but more difficult to control. 

Some coatings and adhesives as well as aluminium foil or aluminium vapour coatings are 
dissolvable already at room temperature but the process may take 1-24 h. By additional 
heating (hot plate or Bunsen burner), the process can be accelerated and shortened to a 
couple of minutes. 

3.5.4  Identification  of  the  layers  peeled  off  and  laid  open  (ATR-FTIR  
spectroscopy) 

Once  a  layer  is  peeled  off,  record  an  ATR-FTIR  spectrum  of  the  surface  laid  open.  It  is 
advisable to record also ATR-FTIR spectra of top and bottom of the layer peeled off. This 
will help to make sure that the layer peeled off was a monolayer. 

If the respective layers were laminated, the adhesive was laid open. It may stick to both 
sides, i.e. the upper layer peeled off and also to the remaining multilayer (see Figure 7). 

PUR adhesive 

Figure 7 PUR adhesive sticks to the aluminium foil and partly also to the PA layer after separation 

16 

 
 
 
 
 
 
 
 
 
ATR-FTIR settings: 

spectral range: 

4000-600 cm-1 

number of scans: 

4 

background:   

air (4 scans, 4000-600 cm-1) 

resolution: 

4 cm-1 

The  spectra  are  identified  by  comparison  to  the  spectra  database  or  other  available 
standard  spectra.  An  overview  on  characteristic  bands  in  FTIR  spectra  of  some  plastic 
polymers, binders for printing inks and adhesives is also provided in Table 8. 

Table 8 Characteristic bands in FTIR spectra ([32], [37], [41], [42]). 

Polymer 

ATR-FTIR spectrum 

Vibration* 

νaCH2 and νsCH2 
δCH2 

Wave number** 
[cm-1] 
3000-2840 
1463 

ρCH2 

725 

νaCH2 and νsCH2 
νaCH3 and νsCH3 
δCH2 and δaCH3 
δsCH3 
ρCH3 
νC-C 

3000-2840 
3000-2840 
1459 
1376 
1167 
998, 973 

ρCH2 

840 

3150-3000 
3000-2840 
1718 
1600-1325 

ν=CH 
νaCH2 and νsCH2 
νC=O 
νPh 
νC(=O)O and δ=CH  1260 
1100 
νO-C and δ=CH 
1018 
δ=CH 
971, 872 
γ=CH 

γPh 

726 

ν=CH 
νaCH2 and νsCH2 
overtones 
νPh 

δ=CH 

γ=CH 

γPh 

3150-3000 
3000-2840 
2000-1660 
1600-1375 
1180, 1154, 1069, 
1028 
906, 842, 758 

700, 540 

Polyethylene 

100

90

80

70

]

T
%

[

60

50

40

30

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

Polypropylene 

100

90

80

]

%

[

Polyethylene 
terephthalate 

Polystyrene 

70

60

50

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

105

95

85

75

65

]

T
%

[

55

45

35

25

15

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

100

]

%

[

90

80

70

60

50

40

30

20

10

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

17 

CH2CH2  nCHCH2  CH3n OOOCH2CH2 OnCHCH2  n 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Polymer 

ATR-FTIR spectrum 

Vibration* 

105

100

95

90

85

Polycarbonate 

]

%

[

80

75

70

65

60

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

Polyamide 6 

100

90

80

70

]

T
%

[

60

50

40

30

20

4000

3500

3000

2500

2000

[cm-1] 

1500

1000

500

Ethylene  vinyl 
acetate 

100

90

80

]

T
%

[

70

60

50

40

Nitrocellulose 
(cellulose 
nitrate) 

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

100

]

%

[

90

80

70

60

50

40

30

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

Polyvinylidene 
chloride 

105

100

95

90

85

]

T
%

[

80

ν=CH 
νaCH3 and νsCH3 
νC=O 
νPh 
νaC-O-C 

δ=CH 

γ=CH 

νNH 
νaCH2 
νsCH2 
νC=O 
δNH and νCN 
δCH2 
ωCH2 and τCH2 
γNH and γC=O 

νaCH2 and νsCH2 
νaCH3 and νsCH3 
νC=O 
δCH2 and δaCH3 
δsCH3 
νC(=O)O 
νO-C and ρCH3 
ρCH2 

νOH...O 
νaCH2 and νsCH2 
νaNO2 
νsNO2 
νC-O 
ρCH2 
νC(=O)O 
νO-C 
νN-C 
ρCH2 
νaCH2 and νsCH2 
δCH2 
γCH2 
νsC-C 
νCCl2 

Wave number** 
[cm-1] 
3150-3000 
3000-2840 
1773 
1506 
1228 
1192, 1162, 1126, 
1015 

831 

3303 
2935 
2860 
1635 
1539, 1276 
1465 
1200 

690 

3000-2840 
3000-2840 
1740 
1469 
1371 
1241 
1020 
720 

3400 
3000-2840 
1654 
1279 
1063 
841 
1223 
1111 
1000 
809 
3000-2840 
1405 
1064 
1044 
600, 655 

75

70

65

60

55

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

18 

 OCH3CH3O OnNH  On CH2CH2CH2 OCH3OnmOHOHHHHOOOOOHOHHHHOOO  O2NNO2NO2O2NNO2NO2nCH2C  ClCln 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Polymer 

ATR-FTIR spectrum 

Vibration* 

Polyester 
acrylate 

aromatic 

R: 
polyester 

105

95

85

75

]

T
%

[

65

55

45

35

25

4000

3500

3000

2500

2000

1500

1000

500

[cm-1] 

ν=CH (aryl) 
νaCH2 and νsCH2 
νC=O 
νC=C (vinyl ester) 
νPh 
δCH2 
δC=C (vinyl ester) 
νC(=O)O 
νasC(=O)-O-C 
(acrylate polymer) 
γC=C (vinyl ester) 
γPh 

number** 

Wave 
[cm-1] 
3150-3000 
3000-2840 
1728 
1636***, 1610*** 
1600-1325 
1453 
1408*** 
1242 
1163 

810*** 
726 

*: 
out-of-plane, ρ: rocking vibration, ω: wagging vibration, τ: twisting vibration 

νa: antisymmetric stretching vibration, νs: symmetric stretching vibration, δ: in-plane deformation, γ: 

**: 
measurement.) 

The wave numbers given refer to transmission spectra and differ slightly from those obtained by ATR 

***: 
The  characteristic  vinyl  ester  moieties  CH2=CH-C(=O)-O~  of  UV/EB  curable  acrylate  printings  or 
adhesives  react  upon  curing  and  form  the  acrylate  polymer  backbone.  As  a  consequence,  the  respective 
characteristic  vinyl  ester  bands  at  1636  (νC=C),  1610  (νC=C),  1408  (δC=C)  and  810  (γC=C)  cm-1  decrease 
and are no longer present/barely-there if the printing ink or adhesive was well cured ([41], [42], [43], [44]). 

3.5.5 Specification of layers with DSC 

The  separated  polymer  layers  can  be  further  characterised  by  their  melting  points  with 
differential scanning calorimetry (DSC) to confirm the results obtained by ATR-FTIR and 
to specify the findings. DSC will enable to distinguish between LDPE, LLDPE and HDPE as 
well  as  PA  6,  PA  66  and  PA  MXD6  and  blends  of  different  polymers  [30].  You  can  also 
perform a DSC of the complete laminate. This will give an idea about the types of plastic 
polymers that are contained in the multilayer sample (see Figure 8). 

]
g
/
W

[

w
o
l
F

t
a
e
H

2

0

-2

-4

-6

-8

-10

-12

-14

-16

-18

-20

ML2_complete

ML2_PE

ML2_PET

ML2_PA

112.78°C 

(LDPE) 

0

50

100

109.84°C 

117.19°C 
150

Temperature [°C] 

219.78°C 

(PA6) 

252.87°C 
(PET) 

253.24°C 

(PET) 

220.88°C 

(PA6) 

200

250

300

Figure 8 DSC diagrams of a laminate (PET/acrylate printing//PURAl foil//PURPA//PURPE) and its single polymer 

layers (PET, PA, PE) after separation 

19 

 CH2 OORn 
 
 
 
 
 
 
 
 
 
 
 
 
 
DSC settings:  

Start temperature:  50°C 

End temperature: 

300°C 

Heating rate:   

20°C/min 

Reference: 

air 

Amount of sample: 

for separated monolayers: 0.5-2.5 mg 

for multilayer samples: 10 mg 

An  overview  about  melting  temperatures  of  some  common  plastic  polymers  in  flexible 
packaging is provided in Table 9. 

Table 9 Glass transition (Tg) and crystalline melting temperatures (Tm) of some common plastic polymers ([30], 

[36], [38]) 

Polymer 

Polyethylene 

Polypropylene 

Polyvinylchloride 

Polyvinylidene chloride 

Atactic polystyrene 

Isotactic polystyrene 

Polyethylene terephthalate 

Polycarbonate (made of Bisphenol A) 

Polyamide 6 

Polyamide 66 

Ethylene vinyl acetate 

Tg [°C] 

Tm [°C] 

-20 

5 

80 

-18 

95 

100 

67 

150 

50 

60 

105-113 (LDPE) 

120 (LLDPE) 

135 (HDPE) 

160 

- 

190 

- 

230 

256 

225 

215 

266 

80-110 (depends on EA content) 

3.5.6  Special  analytical  tests  for  the  identification  of  printing  inks  and 
coatings 

Besides  identification  with  ATR-FTIR  spectroscopy,  some  of  the  printing  inks  and 
coatings can also be identified by simple chemical tests. 

Nitrocellulose (cellulose nitrate, CN) - Diphenylamine test 

To  prepare  the  reagent,  0.1  g  diphenylamine  are  suspended  in  30  mL  water  and  then 
100  mL  concentrated  sulfuric  acid  are  added  carefully.  A  drop  of  the  freshly  prepared 
solution is applied to the sample surface. The reaction is positive for nitrocellulose if the 
reagent turns dark blue. [33] 

Polyvinylidene chloride (PVDC) – Reaction with pyridine and Beilstein test 

A  drop  of  pyridine  is  applied  to  the  sample  surface.  After  2-5  min,  a  drop  of  5%  w/v 
methanolic  sodium  hydroxide  solution  is  added  (1  g  sodium  hydroxide  dissolved  in  20 
mL  methanol).  The  reaction  is  positive  for  PVDC  if  the  surface  turns  brown-black 

20 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
immediately. PVC instead would show a red-brown colour first, and after approx. 5 min 
the colour would turn into black-brown. [33].  

In  addition,  the  Beilstein  test  can  be  performed  to  proof  the  presence  of  chlorine.  A 
copper wire is heated in a Bunsen flame until the flame is colourless. The wire is allowed 
to  cool  down.  Then  a  piece  of  the  sample  is  placed  on  it  (the  chlorine  containing  layer 
should  face  the  wire)  and  the  copper  wire  plus  sample  are  heated  at  the  edge  of  the 
colourless  part  of  the  Bunsen  flame.  A  green  or  blue-green  flame  will  indicate  the 
presence of chlorine when the sample burns. [33] 

3.6 Examples 

Laminate 1 (PET/polyester acrylate printing//PURAl foil//PURPA//PURPE) 

Sample: 

outside 

food contact side 

Step I: General observations 

  The sample is printed (not yet known whether it is a surface or reverse printing) 

  The  sample  contains  an  aluminium  layer  (not  yet  known  whether  it  is  an 

aluminium foil or an aluminium vapour coating). 

Step II: Microtome section (5 µm thickness) 

adh. 
adh. 

polymer film 1 
printing ink 
aluminium foil 
polymer film 2 
adhesive 

polymer film 3 

The microtome section displays that: 

  The  sample  consists  of  3  different  polymer  films  and  an  aluminium  foil. 
Polymer film 1 appears in rainbow colours in polarized light and therefore is likely 
to consist of PET. Polymer film 2 appears green, so it might be a polyamide layer. 

  The printing was applied as a  reverse  print on the bottom side of polymer film 

1. 

21 

 
 
 
 
 
 
 
 
 
  There are no co-extruded layers, all layers are laminated with adhesives. 

  schematic composition: 

polymer 1 
print 
adhesive 
aluminium foil 
adhesive 
polymer 2 
adhesive 
polymer 3 

Step III: ATR-FTIR of the inside (food contact layer) and outside (non-food contact)  

ATR-FTIR: 

PET 

ATR-FTIR: 
laminate(outside) = PET 

complete 

ATR-FTIR: 

PE 

ATR-FTIR: 
laminate(inside) = PE 

complete 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive 

polymer 2 

adhesive 

polymer 3 = PE 

Results: 

  The outside layer consists of PET. 

  The food contact layer consists of PE. 

Step IV: Separation of layers 

From  the  information  gained  in  step  I-III,  the  following  options  arise  to  start  the 
separation of the layers: 

1) 

2) 

The  food  contact  layer  consists  of  PE.  →  Try  to  dissolve/swell  the  PE  layer  in 
DMSO, toluene or xylene and remove it. 

The sample contains an aluminium foil. → Try to dissolve the aluminium in conc. 
HCl to split the sample. 

3+4)  The sample contains an aluminium foil. The plastic films on top of and below the 
aluminium foil must be somehow adhered to it. → Try to dissolve the adhesive on 
top  of  and  below  the  aluminium  foil  in  conc.  HCOOH  or  ethyl  acetate  to  split 
the sample. 

22 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
Step IV: Separation of layers – option 1 – start with DMSO 

1 

complete laminate 

Cut a piece of the sample (complete laminate) 
(approx. 1 cm x 3 cm) and boil it for 1-2 min in 
DMSO to partly dissolve/swell the PE layer. 

2 

3 

ATR-FTIR: 
- (Al) 

4 

5 

tear here! 

The edges of the PE layer are swollen and the 
adhesive that bonds polymer 2 to the aluminium 
foil is partly dissolved. 

→ Part B (adhesive/polymer 2/adhesive/PE) can 
be peeled off from the bottom side of the Al foil. 
Part A (PET/print/adhesive/Al) cannot be further 
separated yet. 

part A 

ATR-FTIR: 

PUR 
part B 

ATR-FTIR:  
part A (top) = PET, part A (bottom) = no 
polymer/coating (aluminium), 

part B (top) = polyester urethane (adhesive), 
part B (bottom) = PE 

Remove the PUR adhesive on top of part B to 
check what is below: 

Dip part B in cold HCOOH and take it out 
immediately(!) to dissolve the PUR adhesive. → 
Rub its top side with a paper towel to remove 
the remaining PUR adhesive. → ATR-FTIR: part 
B (top, PUR adh. removed) = PA 

NOTE: If you immerse part B for >5 s in cold 
HCOOH, the PA will be dissolved. If you 
immerse it in hot HCOOH, the PA will be 
dissolved immediately. 

ATR-FTIR: 

PA 

tear here! 

Separate the PA and PE layer of part B: 

Go back to step 3 → Having a closer look to 
the edges of part B, you can see that the PA 
layer (part B1) can be peeled off. 

6 
part B1 

tear here! 

part B2 

peel off part B1 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 

adhesive 

polymer 3 = PE 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive 

polymer 3 = PE 

part A 

part B 

part B 

23 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7 

part B1 

part B2 

8 

9 

10 

part B2 

part B1 

11 

ATR-FTIR: 
part B1 (top) = polyester urethane (adhesive), 
part B1 (bottom) = PA, 

part A 

part B2 (top) = polyester urethane (adhesive), 
part B2 (bottom) = PE 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

part B1 

part B2 

part B 

Separate the PA and PE layer of part B: 

Go  back  to  step  3  →  If  you  were  not  able  to 
peel off the PA layer (part B1) as shown in step 
5-7,  you  can  boil  part  B  for  2-3  min  in  ethyl 
acetate  →  the  PUR  adhesive  between  PA  and 
PE swells/is partly dissolved 

tear here! 

peel off the PA layer (part B1) 

ATR-FTIR: 

part B1 (top) = polyester urethane (adhesive), 
part B1 (bottom) = PA, 

part B2 (top) = polyester urethane (adhesive), 
part B2 (bottom) = PE 

Remove the PUR adhesive on top of part B2 to 
check what is below: 

boil part B2 for at least 15 min in HCOOH and/or 
acetone,  rub  its  top  side  with  a  paper  towel  to 
remove  the  remaining  PUR  adhesive  →  ATR-
FTIR: part B2 (top) = PE 

Characterisation of the adhesive that bonds the 
reverse printed PET-film to the Al foil: 
Go  back  to  step  3  →  boil  part  A  for  30  s  in 
conc. HCl 

The Al foil on the bottom of part A is completely 
dissolved.  →  ATR-FTIR:  part  A  (bottom,  Al  foil 
removed) = polyester urethane (adhesive) 

To confirm that the “white layer” on the bottom 
side of part A is a reverse printing and to check 
what is below, try to rub it off with a paper towel 
soaked in ethyl acetate (requires some force!). 
→ PUR adhesive and the printing are removed. 
→ ATR-FTIR: part A (bottom, print removed) = 
PET → same like outside → PET-monolayer 

Characterisation of the printing: 

Go  back  to  step  3  →  boil  part  A  for  3-5  min 
DMSO  →  PET  layer  can  be  removed,  printing 
remains  on  the  aluminium  foil  →  ATR-FTIR: 
aluminium 
(top)  =  polyester  acrylate 
(printing) 

foil 

24 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

part B1 

part B2 

part B2 

polymer 1 = PET 

print 

adhesive = PUR 

part A 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

polymer 1 = PET 

print 

adhesive = PUR 

part A 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

  polymer 1 = PET 
print = acrylate 

adhesive = PUR 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

part A 

12 

part A 

ATR-FTIR: 

PE 

13 

14 

15 

ATR-FTIR: 

PUR 

ATR-FTIR: 

PET 

ATR-FTIR: 

PET 

ATR-FTIR: 

polyester 
acrylate 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Step IV: Separation of layers – option 2 – start with conc. HCl 

1 

complete laminate 

Cut a piece of the sample (complete 
laminate) (approx. 1 cm x 3 cm) and boil it in 
conc. HCl to partly dissolve the aluminium 
foil 

2 

ATR-FTIR: PET 

part A 

ATR-FTIR: 

PUR 

part B 

after 30 s the adhesive that laminates part A 
(PET/print) to the aluminium foil is (partly) 
dissolved, while the aluminium foil is only 
dissolved at its edges 

→ peel off part A 

→ ATR-FTIR: part A (top) = PET, part A 
(bottom) = polyester urethane (adhesive) 

3 

ATR-FTIR: PUR 

part B* 

immerse part B again for 10 s in boiling 
conc. HCl → the aluminium layer is dissolved 
immediately → part B* (adhesive/polymer 
2/adhesive/PE) remains → ATR-FTIR: part 
B* (top) = polyester urethane (adhesive), 
part B*(bottom) = PE 

part B* 

Separate polymer 2 and the PE layer: 

boil part B* for 2 min in ethyl acetate to partly 
dissolve/swell the adhesive between polymer 
2 and the PE layer 

polymer 1 = PET 

print 

adhesive = PUR 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

polymer 1 = PET 

print 

adhesive = PUR 

Al foil 

adhesive 

polymer 2 

adhesive 

polymer 3 = PE 

polymer 1 = PET 

print 

adhesive = PUR 

Al foil 

adhesive = PUR 

polymer 2 

adhesive 

polymer 3 = PE 

part A 

part A 

part B 

part B* 

scratch/tear 

polymer 2 (part B1) became brittle already 
while boiling in conc. HCl → now it can be 
scratched off with a spatula 

ATR-FTIR: 
part B1 (top) = polyester urethane 
(adhesive), part B1 (bottom) = PA, 

part B2 (top) = polyester urethane 
(adhesive), part B2 (bottom) = PE 

ATR-FTIR: PA 

ATR-FTIR: 

PET 

Go back to step 2 – To confirm that the 
“white layer” on the bottom side of part A is a 
reverse printing and to check what is below, 
try to rub it off with a paper towel soaked in 
ethyl acetate (requires some force!). → PUR 
adhesive and the printing are removed. → 
ATR-FTIR: part A (bottom, print removed) = 
PET → same like outside → PET-monolayer 

part A 

polymer 1 = PET 

print 

adhesive = PUR 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

25 

4 

5 

6 

ATR-FTIR: PUR 

part B2 

7 

part B1 

part A 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Step IV: Separation of layers – option 3 – start with conc. HCOOH 

1 

complete laminate 

tear here! 

ATR-FTIR: PUR 

part B 

2 

3 

part A 

4 

5 

part B1 

ATR-FTIR: PA 

6 

part A 

Cut a piece of the sample (complete 
laminate) (approx. 1 cm x 3 cm) and boil it 
for 1 min in conc. HCOOH to partly 
dissolve the adhesives above and below 
the aluminium foil. 

(Attention: If you boil the sample for 
>5min, polymer 2 (PA) is dissolved as 
well.) 

Part A (PET/print/adhesive) can be peeled 
off from the top of the aluminium foil... 

tear here! 

ATR-FTIR: 

PUR 

part B 

...and part B (adhesive/polymer 
2/adhesive/PE) can be peeled off from the 
bottom of the aluminium foil. 

→ ATR-FTIR: 

part A (top) = PET, part A (bottom) = 
polyester urethane (adhesive), 

part B (top) = polyester urethane 
(adhesive), part B (bottom) = PE 

Separate polymer 2 and the PE layer: 

boil part B for 2 min in ethyl acetate to 
partly dissolve/swell the adhesive between 
polymer 2 and the PE layer 

tear here! 

ATR-FTIR: 

part B1 (top) = polyester urethane 
(adhesive), part B1 (bottom) = PA, 

part B2 (top) = polyester urethane 
(adhesive), part B2 (bottom) = PE 

part B2 

ATR-FTIR: 

PUR 

ATR-FTIR: 

PET 

Go back to step 3 – Remove the PUR 
adhesive and the acrylate printing on the 
bottom side of part A to check what is 
below and to confirm that the "white layer" 
is a reverse printing as described in 
option 2 step 7 

26 

polymer 1 = PET 

print 

adhesive = PUR 

Al foil 

adhesive = PUR 

polymer 2 

adhesive 

polymer 3 = PE 

part A 

part B 

polymer 1 = PET 

print 

adhesive = PUR 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

polymer 1 = PET 

print 

adhesive = PUR 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

part B1 

part B2 

part A 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Step IV: Separation of layers – option 4 – start with ethyl acetate 

1 

complete laminate 

Cut a piece of the sample (complete laminate) 
(approx. 1 cm x 3 cm) and boil it for 1 min in 
ethyl acetate to partly dissolve/swell the 
adhesives on top of and below the aluminium 
foil. 

ATR-FTIR: 

PUR 

The adhesive on the bottom of the aluminium 
foil is partly dissolved. → part B 
(adhesive/polymer 2/adhesive/PE) can be 
peeled off from the bottom side of the Al foil. 

part B 

→ ATR-FTIR: 

part A 

part A (top) = PET, part A (bottom) = no 
polymer/coating (aluminium foil), 

part B (top) = polyester urethane (adhesive), 
part B (bottom) = PE 

Separate polymer 2 and the PE layer: 

If necessary: Boil part B again for 1 min in ethyl 
acetate to partly dissolve/swell the adhesive 
between polymer 2 and the PE layer. 

polymer 2 (part B1) can be peeled off 

part B2 

ATR-FTIR: - (Al) 

part B 

tear here! 

part B1 

2 

3 

4 

5 

part B1 

ATR-FTIR: 

PA 

part B2 

ATR-FTIR: 

PUR 

ATR-FTIR: 
part B1 (top) = polyester urethane (adhesive), 
part B1 (bottom) = PA, 

part B2 (top) = polyester urethane (adhesive), 
part B2 (bottom) = PE 

6 

7 

8 

ATR-FTIR: PE 

ATR-FTIR: PA 

Remove the PUR adhesive on top of part B2 as 
described in option 1 step 11 

Go back to step 2 to remove the PUR adhesive 
on top of the PA layer and confirm that there is 
no more layer on top of the PA → follow step 4 
described in option 1 

NOTE: If you try to immerse the isolated PA 
layer (part B1) in HCOOH (cold or hot) to 
remove the PUR adhesive on its top, the whole 
PA layer will be dissolved immediately! You 
have to go back to step 2 first and immerse the 
PA/PE laminate (part B) instead! 

ATR-FTIR: 

PUR 

Characterisation of the adhesive that bonds the 
reverse printed PET-film to the Al foil: 

Go back to step 2 and follow step 12-13 
described in option 1 

27 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 

adhesive 

polymer 3 = PE 

part A 

part B 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

polymer 1 = PET 

print 

adhesive 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive 

polymer 3 = PE 

part B1 

part B2 

part B2 

part B 

polymer 1 = PET 

print 

adhesive = PUR 

part A 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
9 

10 

ATR-FTIR: 

PET 

To confirm that the “white layer” on the bottom 
side of part A is a reverse printing and to check 
what is below, follow the descriptions in option 
1 step 14 

Characterisation of the printing: 

ATR-FTIR: 

Go back to step 2 and follow step 15 
described in option 1 

ATR-FTIR: PET 

polyester 
acrylate 

part A 

polymer 1 = PET 

print = acrylate 

adhesive = PUR 

Al foil 

adhesive = PUR 

polymer 2 = PA 

adhesive = PUR 

polymer 3 = PE 

SUMMARY OF RESULTS: 

Identified composition of layers: 

PET/polyester acrylate printing//PURAl foil//PURPA//PURPE 

outside 

polymer 1 = PET 

print = polyester acrylate 

adhesive = polyester urethane 

aluminium foil 

adhesive = polyester urethane 

polymer 2 = PA 

adhesive = polyester urethane 

polymer 3 = PE 

food contact side 

28 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Laminate 2 (PA/polyester urethane printing//PURPE) 

Sample: 

outside 

food contact side 

Step I: General observations 

  The sample is partially printed (surface or reverse printing → not yet known). 

  The sample does not contain an aluminium layer. 

Step II: Microtome section - not available 

Step III: ATR-FTIR of the inside (food contact layer) and outside (non-food contact) 

ATR-FTIR: complete laminate (outside) = PA 

ATR-FTIR: complete laminate (inside) = PE 

Results:  

  The outside layer consists of PA. 

  The food contact layer consists of PE. 

Step IV: Separation of layers 

From  the  information  gained  in  step  I-III,  the  following  options  arise  to  start  the 
separation of the layers: 

1) 

2) 

The  food  contact  layer  consists  of  PE.  →  Try  to  dissolve/swell  the  PE  layer  in 
DMSO, toluene or xylene and remove it. 

The  outside  layer  consists  of  PA.  →  Try  to  completely  dissolve  the  PA  layer  in 
conc. HCOOH to check what is below. 

29 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Step IV: Separation of layers – option 1 – start with DMSO 

1 

complete laminate 

2 

3 

part A 

part B 

4 

5 

Cut a piece of the sample (complete laminate) (approx. 1 cm x 
3 cm) and boil it in DMSO to swell the PE layer on the bottom of 
the sample. 

After 1-2 min, the upper layer starts to separate (see edges) but 
cannot yet be peeled off. Therefore, boil the sample for another 2 
min in DMSO. 

Part A can be peeled off from the top of the sample. The printing 
is laid open, it sticks to the bottom of part A and the top of part B. 

part B 

ATR-FTIR: 

part A (bottom, unprinted) = PA, part A (bottom, green printing) = 
polyester urethane (printing), 

part B (top, unprinted) = polyester urethane (adhesive), part B 
(top, green printing) = polyester urethane (printing) 

Remove the printing from the bottom of part A and from the top of 
part B to check what is below: 
The printing can be rubbed off with a paper towel soaked in ethyl 
acetate. (If necessary, you can also boil the sample in ethyl 
acetate.) 

→ ATR-FTIR: part A (bottom, print removed) = PA, part B (top, 
print+adhesive removed) = PE 

part A 

part B 

part A 

6 

part A 

Check whether part A consists only of PA by dissolving it 
completely in cold HCOOH: 

Dip part A into cold HCOOH. 

30 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7 

8 

part B 

9 

10 

Part A is dissolved immediately. Only the green printing ink film 
remains in the beaker. → Part A seems to consist only of PA. 

Check whether part B is really a monolayer or whether it consists 
of coextruded layers, e.g. two PE layers with an EVOH layer in 
between: 
boil part B for 5 min in conc. H2SO4 → if there was an EVOH 
layer in between, it would be decomposed (turn black) and you 
would see a thin black-brown line at the edges of the sample 

Residues of the green printing on top of part B were decomposed 
(turned black). → Can be rubbed off with a paper towel. 

Having a closer look to the edges of part B after treatment with 
H2SO4, you can see that there is no black line visible. → There is 
no EVOH layer sandwiched between two PE layers. → The PE 
layer is probably a monolayer. 

31 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Step IV: Separation of layers – option 2 – start with HCOOH 

1 

complete sample 

Cut a piece of the sample (complete sample) (approx. 1 cm x 
3 cm) and boil it for 15 min in HCOOH to completely dissolve the 
PA layer on top of the sample 

ATR-FTIR: 

top 

top (PA removed, green printed parts) = polyester urethane 
(printing), 

top (PA removed, unprinted/clear parts) = polyester urethane 
(adhesive), 

bottom 

bottom = PE 

Remove the printing and adhesive to check what is below: 

The printing and adhesive can be rubbed off with a paper towel 
soaked in ethyl acetate. (If necessary, you can also boil the 
sample in ethyl acetate.) → ATR-FTIR: top (PA, print and 
adhesive removed) = PE 

Now that you know, that the sample is reverse printed, you should 
check that you did not dissolved anything else during step 1 apart 
from the PA layer. Therefore, try to separate the PA layer from the 
complete sample and check its bottom side: 

Take a piece of the complete sample and boil it for 2 min in ethyl 
acetate to partly dissolve/swell the adhesive that bonds the 
reverse printed PA film to the rest of the sample. 

2 

3 

4 

5 

part A 

part B 

The PA layer (part A) can be peeled off. The printing sticks to 
both sides (the bottom of part A and the top of part B). 

6 

part B 

part A 

part A 

7 

part B 

Remove the printing from the bottom of part A and from the top of 
part B to check what is below: 

The printing can be rubbed off with a paper towel soaked in ethyl 
acetate. (If necessary, you can also boil the sample in ethyl 
acetate.) → ATR-FTIR: part A (bottom, print removed) = PA, part 
B (top, print+adhesive removed) = PE 

part B 

Check whether part B is really a monolayer or whether it consists 
of coextruded layers, e.g. two PE layers with an EVOH layer in 
between: 
→ follow the descriptions in option 1 step 8-10 

32 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
8 

part A 

Check whether part A consists only of PA by dissolving it 
completely in cold HCOOH: 

Go back to step 6 and follow the descriptions in option 1 step 6-
7 

SUMMARY OF RESULTS: 

Identified composition of layers: 

PA/polyester urethane printing//PURPE 

outside 

PA 

print = polyester urethane 

adhesive = polyester urethane 

PE 

food contact side 

33 

 
 
 
 
 
 
 
 
 
 
 
 
 
References 

[1]  Alfatherm  SpA  (2014).  Packaging  Films.  Retrieved  April  24,  2014, 

from 

http://www.alfatherm.it/en/applications/packaging-films/ 

[2]  Sidwell  JA  (1992).  Food  Contact  Polymeric  Materials.  Rapra  Review  Reports.  Vol.  6 

(1), Report 61 

[3]  Anon. (1996). Understanding Plastic Film: Its Uses, Benefits and Waste Management 
from 

Options. 
http://plastics.americanchemistry.com/Understanding-Plastic-Film 

Retrieved 

2014, 

April 

24, 

[4]  Krohn JV, Todd WG, Culter JD (n.d.). Optimizing barrier performance of multi-layer 
from 

polyethylene 
http://www.lyondellbasell.com/techlit/techlit/Brochures/Barrier%20Performance%20
Multi-Layer%20Film%209366.pdf 

Retrieved 

2014, 

films. 

April 

24, 

[5]  Haux  V  (2006).  Multilayer  films:  a  solution  for  demanding  food  packaging 
from 

applications. 
http://www.kpfilms.com/de/news/pdfs/case%20studies/Multilayer%20films%20a%2
0solution%20for%20demanding%20food%20packaging%20applications%20English.
pdf 

19-22.  Retrieved  April 

2014, 

Food, 

24, 

3, 

p. 

[6]  Goetz W (2003). Polyamide for Flexible Packaging Film. 2003 PLACE Conference, 12-
from 

Italy. 
14  May 
http://www.tappi.org/content/enewsletters/eplace/2004/10-2goetz.pdf 

Retrieved 

Rome, 

2003, 

2014, 

April 

24, 

[7]  PolyOne Corporation (2013). Spartech Packaging Sheet Products. Retrieved April 24, 
from 

2014, 
http://www.spartech.com/packaging/products.html#productSummaryChart 

[8]  Kenneth  J.  Valentas,  Enrique  Rotstein,  R.  Paul  Singh  (1997).  Handbook  of  Food 

Engineering Practice. CRC Press LLC, p. 305 et seqq. 

[9]  Kit  L.  Yam  (ed.)  (2009).  The  Wiley  Encyclopedia  of  Packaging  Technology.  3rd 

edition, John Wiley & Sons, p. 974 

[10]  ILSI  Europe  Packaging  Material  Task  Force  (2000).  Packaging  Materials:  1. 
Polyethylene  Terephthalate  for  Food  Packaging  Applications.  ILSI  Europe  Report 
Series. 
from 
24, 
http://www.ilsi.org/Europe/Publications/R2000Pac_Mat1.pdf 

Retrieved 

Brussels. 

2014, 

April 

[11]  ILSI  Europe  Packaging  Material  Task  Force  (2002).  Packaging  Materials:  2. 
Polystyrene  for  Food  Packaging  Applications.  ILSI  Europe  Report  Series.  Brussels. 
Retrieved 
from 
http://www.ilsi.org/Europe/Publications/R2002Pac_Mat2.pdf 

2014, 

April 

24, 

[12]  Tice  P  (2002).  Packaging  Materials:  3.  Polypropylene  as  a  Packaging  Material  for 
Foods and Beverages. ILSI Europe Report Series. Brussels. Retrieved April 24, 2014, 
from http://www.ilsi.org/Europe/Publications/R2002Pac_Mat3.pdf 

[13]  Tice  P  (2003).  Packaging  Materials:  4.  Polyethylene 

for  Food  Packaging 
Applications.  ILSI  Europe  Report  Series.  Brussels.  Retrieved  April  24,  2014,  from 
http://www.ilsi.org/Europe/Publications/R2003Pac_Mat.pdf 

[14]  Dixon  J  (2011).  Packaging  Materials:  9.  Multilayer  Packaging  for  Food  and 
Beverages.  ILSI  Europe  Report  Series.  Brussels.  Retrieved  April  24,  2014,  from 
http://www.ilsi.org/Europe/Publications/ILSI-11-011%209%20pack%2003.pdf 

[15]  Sutter J, Dudler V, Meuwly R (2011). Packaging Materials: 8. Printing Inks for Food 
Packaging.  Composition  and  Properties  of  Printing  Inks.  ILSI  Europe  Report  Series. 
Brussels. Retrieved April 24, 2014, from http://www.ilsi.org/Europe/Documents/ILSI-
11-015%20printing%20inks_finallr.pdf 

34 

 
 
 
[16]  CEPE (2009). Code of Practice for Coated Articles where the Food Contact Layer is 
a  Coating.  Working  Document.  Edition  4.  2nd  February  2009  (available  at 
http://www.cepe.org/EPUB/easnet.dll/ExecReq/Page?eas:template_im=100087&eas:
dat_im=05043D) 

[17]  Americk  Primopost 

(2014).  Coatings.  Retrieved  April  24,  2014, 

from 

http://www.primopost.com/coatings.asp 

[18]  Paisley  K  (2007).  PVDC  –  New  Developments,  New  Opportunities.  2007  TAPPI 
PLACE  Conference,  19  September  2007,  St.  Louis,  USA.  Retrieved  April  24,  2014, 
from http://www.tappi.org/content/events/07place/papers/paisley.pdf 

[19]  Packflex  Flexible  Packaging  Inks  Division  (2012).  Rotogravure  Printing  Inks. 
Retrieved  April  24,  2014,  from  http://www.flexiblepackaginginks.com/rotogravure-
printing-inks.htm 

[20]  Packflex  Flexible  Packaging  Inks  Division  (2012).  Flexographic  Printing  Inks. 
Retrieved  April  24,  2014,  from  http://www.flexiblepackaginginks.com/flexographic-
printing-inks.htm 

[21]  Xiamen  Green  spring  environmental  Greenway  Technology  Materials  Co.  (2013). 
Rotogravure  reverse  printing  water  based  ink  for  laminating  plastic  film.  Retrieved 
April 24, 2014, from http://www.greenspring-ink.com/en/pd.jsp?id=653&_pp=2_351 

[22]  DIC  India  Limited  (n.d.).  Gravure  Ink.  Retrieved  April  24,  2014, 

from 

http://www.dicindialtd.co/pns-gravure-ink.html 

[23]  Colorcon  (2012).  No-Tox  Products.  Technical  Data.  No-Tox®  Gravure  Vinyl  Inks. 
from 

(02/12). 

2014, 

April 

24, 

NT14 
http://www.colorcon.com/notox/literature/sales/NT14-Gravure-
Offset%20Gravure%20Vinyl_2.pdf 

Retrieved 

[24]  Colorcon  (2012).  No-Tox  Products.  Technical  Data.  No-Tox®  Flexo/Gravure  Inks. 
from 

NT04 
http://www.colorcon.com/notox/literature/sales/NT04-Flexo-Gravure_2.pdf 

Retrieved 

(02/12). 

2014, 

April 

24, 

[25]  Lapin  SC  (2006).  Ink  Bonding  Properties  of  Electron  Beam  Cured  Adhesive 
Laminates  for  Flexible  Packaging.  2006  PLACE  Conference  17-21  September  2006, 
from 
Cinninati, 
http://www.tappi.org/content/enewsletters/eplace/2007/06PLA45.pdf 

Retrieved 

2014, 

Ohio, 

USA. 

April 

24, 

[26]  Marsh  K  and  Bugusu  B  (2007).  Food  Packaging  –  Roles,  Materials,  and 

Environmental Issues. Journal of Food Science. 72(3), pp. R39-R55 

[27]  Richter L, Biedermann-Brem S, Simat TJ, Grob K (2014). Internal bags with barrier 
layers  for  foods  packed  in  recycled  paperboard:  recent  progress.  Eur  Food  Res 
Technol. DOI 10.1007/s00217-014-2208-x 

[28]  Schut  JH  (2000).  Polystyrene  blown  film  starts  to  get  some  respect.  Plastics 
Technology, 
from 
http://www.ptonline.com/articles/polystyrene-blown-film-starts-to-get-some-respect 

November 

Retrieved 

2014, 

2000. 

April 

24, 

[29]  U.S. Environmental Protection Agency (2002). Flexographic Ink Options: A Cleaner 
Technologies Substitutes Assessment. Volume 1. Chapter 4:  Performance.  EPA 744-
R-02-001A. 
from 
April 
Retrieved 
http://www.epa.gov/dfe/pubs/flexo/ctsa/index.html 

2014, 

24, 

[30]  Forrest JM (2002). Analysis of Plastics. Rapra  Review Reports. Vol. 13 (5), Report 

149 

[31]  Dow  Wolff  Cellulosics  GmbH  (n.d.).  Nitrocellulose.  Retrieved  April  25,  2014,  from 
http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_08a6/0901b803808a6
80d.pdf?filepath=/822-00007.pdf&fromPage=GetDoc 

35 

 
 
 
[32]  Verleye GAL, Roeges NPG, De Moor MO (2001).  Easy Identification of Plastics and 

Rubbers. Shawbury, Shrewsbury, Shropshire (UK): Rapra Technology Limited. 

[33]  Braun  D  (1996).  Simple  Methods  for  Identification  of  Plastics.  With  the  Plastics 
Identification Table by Hansjürgen Saechtling (translated by Edmund Immergut). 3rd, 
revised edition. Cincinnati, Ohio : Hanser/Gardner Publications; Munich: Hanser 

[34]  Dow  Chemical  Company  (2000).  Vinylidene  Chloride  Monomer  and  Polymers.  A 
Technical  Report  on  VDC  and  PVDC.  (Reprinted  from  Kirk-Othmer:  Encyclopedia  of 
Chemical Technology, 4th  edition, vol. 24.  New York: John Wiley & Sons,  Inc. 1997, 
pp. 
from 
http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_005d/0901b8038005d
707.pdf?filepath=plastics_ap/pdfs/noreg/190-00347.pdf&fromPage=GetDoc 

882-923.) 

Retrieved 

2014, 

May 

3, 

[35]  Scheirs  J  (2000).  Compositional  and  Failure  Analysis  of  Polymers.  A  practical 

approach. Chichester: John Wiley & Sons, Ltd., p. 102 

[36]  Vasile  C,  Pascu  M  (2005).  Practical  Guide  to  Polyethylene.  Shrewsbury:  Rapra 

Technology Limited 

[37]  Bower  DI,  Maddams  WF  (1989).  The  vibrational  spectroscopy  of  polymers. 

Cambridge Solid State Science Series. Cambridge: Cambridge University Press 

[38]  Arsac  A,  Carrot  C,  Guillet  J  (2000).  Determination  of  primary  relaxation 
temperatures  and  melting  points  of  ethylene  vinyl  acetate  copolymers.  J.  Therm. 
Anal. Cal., 61(3): 681-685 

[39]  Jopko  L  (2004).  Flexible  Packaging  Adhesives  –  The  Basics.  Retrieved  May  08, 
2014, from http://www.tappi.org/content/enewsletters/eplace/2004/14-3Jopko.pdf 

[40]  Rolando  T.E.  (1998).  Solvent-Free  Adhesives.  Rapra  Review  Reports.  Vol.  9  (5), 

Report 101 

[41]  Bauer  F,  Decker  U,  Czihal  K,  Mehnert  R,  Riedel  C,  Riemschneider  M,  Schubert  R, 
Buchmeister  MR  (2009).  UV  curing  and  matting  of  acrylate  nanocomposite  coatings 
by 172 nm excimer irradiation. Prog. Org. Coat., 64: 474-481 

[42]  Photoinitiator-free  UV  curing  and  matting  of  acrylate-based  nanocomposite 

coatings: Part 3. Prog.Org. Coat., 77: 1085-1094 

[43]  Park  Y-J,  Lim  D-H,  Kim  H-J,  Park  D-S,  Sung  I-K  (2009).  UV-  and  thermal-curing 
behaviors of dua-curable adhesives based on epoxy acrylate oligomers. International 
Journal of Adhesion and Adhesives, 29: 710-717 

[44]  Lee  B-H,  Choi  J-H,  Kim  H-J  (2006).  Coating  performance  and  characteristics  for 
UV-curable  aliphatic  urethane  acrylate  coatings  containing  Norrish  Type  I 
photoinitiators. JCT Research, 3(3): 221-229 

36 

 
 
 
 
 
 
 
Annex 1: Example of protocol for operating a rotary microtome 

Note:  the  example  given  is  the  one  used  for  JRC  FCM  activities.  It  is  intended  as  an  illustrative 
example only and in no way constitutes a recommendation nor any commercial endorsement. 

Scope and field of application 

This procedure describes the activities to be carried out in order to properly handle and 
maintain the rotary microtome SLEE medical CUT 4062 accessible in the FIT-EURL group 
of  the  CAT  Unit,  Bld.  26,  Lab  017.  The  rotary  microtome  is  used  to  perform  cross-
sections of multilayer plastic films. Strict respect of this SOP is required to all operators 
within FIT-EURL laboratories. 

Materials and reagents 

Materials needed for cross-sectioning 

 

foldable plastic plates in which the multilayer plastic film is sandwiched during 
sectioning (e.g. 40 x 10 x 1.5 mm, polystyrene, white, purchasable from 
MicroKern (www.micro-kern.de), Art.no. MK99997); 

  sectioning tape (highly transparent, with low birefringence) (e.g. 21 x 14.8 cm, 
Avery GRAPHICS, purchasable from MicroKern (www.micro-kern.de), Art.no. 
MK99990_100B). 

Materials needed for embedding of cross-sections 

  microscope slides (76 x 26 mm); 
  cover slips (24 x 24 mm); 
  mounting medium for coverslipping of slides (e.g. LEICA CV Ultra, Art.no. 0709 

36261); 
  paper towels. 

Equipment 

Rotary microtome 

rotary microtome: SLEE medical CUT 4062 (SN: A 14 0017) 

 
  specimen holder: standard object clamp, orientable (SLEE medical, Art.no. 

10090006); 

  blade holder; 
  disposable blades (stainless steel, low profile, e.g. SLEE medical, Art.no. 

28407000). 

Other laboratory equipment 

  scissors (1 pair of ordinary scissors, 1 pair of dissecting scissors); 
  paint brush; 
 
tweezers; 
  dissecting needle; 
  permanent marker; 
  Allen key (size 3 x 100 mm, 4 x 150 mm, 6 x 100 mm). 

37 

 
 
 
 
 
 
 
 
 
Use of the equipment (Microtome sectioning) 

To  set  up  the  microtome  and  to  perform  the  microtome  sectioning,  carry  out  the 
following instructions in the given order. Please fill in the instrument table after use (see 
Annex 1). 

The  microtome  should  be  equipped  with 
the object orientation  (A).  If not, install 
it and fasten all 4 screws using an Allen 
key (size 4 x 150 mm). 

NOTE:  To  access  the  screws  of  the 
object  orientation,  it  may  be  necessary 
to  move  the  specimen  holder  towards 
you by turning the trimming hand wheel 
(B) on the left counterclockwise. 

Now take the standard object clamp and 
unscrew it. 

Install the corpus of the standard object 
clamp (C) at the object orientation. Use 
an Allen key (size 3 x 100 mm) to fasten 
the two screws. 

Install the orientable standard object clamp 

A 

B 

C 

38 

 
 
 
 
 
 
 
 
          
          
 
 
Reassemble  the  remaining  parts  of  the 
standard object clamp. 

Check  the  position  of  the  specimen 
holder. If it sticks out a lot, move it back 
inwards  by  turning  the  trimming  hand 
wheel  (B)  clockwise.  Otherwise  it  might 
be difficult later on to position the blade 
holder correctly and the limit for moving 
the  specimen  holder  outwards  might  be 
reached  during  trimming  or  sectioning. 
An  acoustic  noise  informs  you  that  the 
limit  to  move  the  specimen  holder 
inwards/outwards  was  reached.  Stop 
turning  the  trimming  hand  wheel  (B) 
immediately when you hear it. 

B 

Inserting a sample of a multilayer plastic film into the standard object clamp 

Cut a strip of approx. 0.8 cm x 1.5  cm, 
but  no  bigger  than  1  cm  x  2  cm,  from 
the  multilayer  plastic  film  sample.  Use 
the dissecting scissors to do so. With an 
ordinary  pair  of  scissor,  you  might 
squeeze the edges of the sample strip. 

Insert  the  sample  strip  in  between  one 
of  the 
foldable  plastic  plates.  Pay 
attention  whether  the  non-food  contact 
side  (outside)  of  the  sample  faces 
upwards  or  downwards.  To  avoid 
confusion, 
face 
upwards. 

should  always 

it 

39 

 
 
 
 
 
 
 
 
 
     
     
     
 
NOTE:  If  later  on  problems  appear  and 
the  sections  are  not  cut  off  completely 
from  the  specimen,  the  right  edge 
(which  will  be  the  upper  edge  when 
inserted into the standard object clamp) 
of  the  foldable  plate  with  the  sample 
strip  in  between  can  be  cut  off  with  a 
razor blade. 

Insert  the  folded  plastic  plate  into  the 
standard  object  clamp.  Again  the  non-
food  contact  side  (outside)  of  the 
sample should face upwards. 

(see 

If  necessary,  adjust  the  angle  of  the 
object  orientation  as  described  in  the 
Error! 
operation  manual 
eference  source  not  found.  p.  15 
section  7.3).  Adjusting  the  screws  on 
top  (D)  and  on  the  left  (E)  of  object 
the  sample  should  be 
orientation, 
oriented parallel to the x-z-plane. This is 
necessary  to  avoid  problems  in  setting 
the  blade  angle  in  a  later  stage.  Then 
loosen the metal arm (F) on the right to 
change  the  orientation in the  x-z-plane. 
The  sample  should  be  oriented  neither 
parallel  nor  perpendicular  to  the  blade 
(see  Error!  Reference  source  not 
ound.).  Best  is  an  oblique  angle  of 
about 15°-45° in the x-z-plane. 

F 

D 

outside 

E 

30° 

z 

y 

x 

Install the blade holder and adjust the blade angle 

G 

After having inserted the specimen and 
adjusted the object orientation, take out 
the blade holder from the plastic box. Be 
careful  when  handling  the  blade  holder. 
The  blade  is  very  sharp  and  you  can 
easily  injure  yourself  when  touching  it. 
The  red  metal  bar  ("finger  protection 
guard") (G)  should always be folded up 
to  shield  the  blade  and  to  prevent 
accidently touching it. 

40 

 
 
 
 
 
 
 
 
 
 
Put  the  blade  holder  on  the  metal  rail 
and  fasten  it  by  pulling  tight  the  metal 
arm (H) on the lower left. 

Set  the  blade  angle  by  loosening  the 
screw  on  the  lower  right  (I)  with  an 
Allen  key  (size  6  x  100  mm).  As  all 
blades  are  wedge  shaped,  the  correct 
blade  angle  should  always  be  set  in  the 
following  way  (see  Error!  Reference 
ource  not  found.):  The  lower  bevel 
face has to be positioned parallel to the 
specimen block and the plane of motion. 
Then the  angle should be slightly raised 
by  another  1/2  degree.  This  prevents 
the  lower  bevel  face  from  sliding  over 
the 
specimen  block  and  possibly 
producing  friction  damage.  Using  the 
low  profile  disposable  blades  made  of 
stainless  steel  (SLEE  medical  Art.no. 
28407000), an angle of about 2° should 
be suitable for use. 

H 

2° 

I 

Position the blade holder for trimming 

trimming,  check  again 

the 
Before 
position  of  the  blade  holder.  Loosen  the 
hand  wheel  stop  (J)  on  the  right  and 
slowly  turn  the  hand  wheel  (K)  on  the 
right  to  move  the  specimen  holder 
down.  

J 

K 

41 

 
 
 
 
 
 
 
 
 
are 

The  blade  holder  should  be  positioned 
close  to  the  specimen  but  the  blade 
should not yet touch the specimen. 0.5-
1  mm  of  distance  between  blade  and 
specimen 
enough.  Otherwise 
trimming  will  take  much  longer.  If 
necessary,  reposition  the  blade  holder 
by  loosening  the  metal  arm  (H)  on  the 
lower  left.  (NOTE:  Refasten  the  hand 
wheel  stop  (J)  before  you  readjust  the 
blade holder position.) 

L 

Select  a  virgin  part  of  the  blade  for 
cutting  by  shifting  the  blade  holder 
horizontally.  To  do  so,  loosen  the  metal 
arm  (L)  on  the  lower  right  of  the  blade 
holder block. 

Those parts of the blade that were used 
already for sectioning are marked with a 
small  dot.  Starting  from  the  last  mark 
on  the  blade,  move  the  blade  holder 
about  1  cm  further  left  to  arrive  at  a 
"virgin"  part  of  the  blade.  If  you  have 
reached  the  end  of  the  blade  already, 
change  the  blade  and  use  a  new  one 
(see 0) 

Mark 
the 
the  new  position  where 
specimen  will  touch  the  blade  with  a 
small  dot  on 
the  blade  using  a 
permanent marker. 

42 

 
 
 
 
 
 
 
 
 
 
Perform trimming 

M 

O 

N 

M 

G 

J 

Set the trimming thickness at the upper 
grey  knob  (M)  on  the  left  front  side  of 
the  microtome,  labelled  with  "TRIM".  It 
can be varied from 10 to 40 µm. Usually 
a trimming thickness of 30 µm is ok. 

To  set  the  cutting  thickness  for  the 
actual  microtome  sections,  turn  the 
lower, black/grey knob (N). The current 
setting  for  the  section  thickness  is 
shown  in  the  small  window  next  to 
"CUT"  (O).  For  the  analysis  of  plastic 
multilayers,  sections  of  5  µm  are 
generally  well  suited.  For  very  fragile 
samples,  also  thicker  sections  of  10  µm 
could be performed. 

To  start  trimming,  fold  down  the  finger 
protection  guard  (red  metal  bar)  (G), 
loosen  the  hand  wheel  stop  (J)  and 
slowly  turn  the  hand  wheel  (K)  on  the 
right  clockwise  while  pressing  the  grey 
"TRIM" knob (M) on the left. With every 
turn  of  the  hand  wheel,  the  specimen 
holder  will  move  30  µm  towards  you  as 
set before on the "TRIM" knob (M). 
NOTE:  If  you  turn  the  hand  wheel  (K) 
anticlockwise,  the  specimen  holder  will 
move 30 µm towards you as well. It will 
not move backwards. 

After some turns of the hand wheel (K), 
the  specimen  will  touch  the  blade  and 
sections  of  30 µm  thickness  will  be  cut 
from  the  specimen.  Continue  like  this 
until a plane and clear specimen surface 
is obtained (incl. the white plastic plates 
is 
in  between  which  the  specimen 
sandwiched).  Do  not  perform 
the 
trimming  sections  too  fast  to  avoid 
damage of the specimen surface. 

43 

 
 
 
 
 
 
 
 
 
Then perform another 5-10 sections of 5 
µm  without  pressing  the  "TRIM"  knob 
(M) to really obtain a smooth specimen 
surface.  When  finished,  fasten  the  hand 
wheel stop (J). 

Remove  section material from the blade 
and  the  specimen  holder  with  a  dry 
paint  brush.  Be  careful  not  to  cut 
yourself. 

The blade and specimen block should be 
completely  clean  before  you  proceed 
with the next steps. 

G 

After  cleaning,  fold  up  again  the  finger 
protection guard (G). 

44 

 
 
 
 
 
 
 
 
 
Perform sectioning 

Cut  a  piece  (approx.  1  cm  x  1.5  cm) 
from  the  sectioning  tape.  You  can  use 
an ordinary pair of scissors to do so. Do 
scissors, 
not  use 
otherwise they may become blunt. 

dissecting 

the 

tape  and  stick 

Remove  the  paper  from  the  backside  of 
the  sectioning 
the 
sectioning  tape  to  the  surface  of  the 
specimen.  Carefully  press  it  to  the 
specimen  surface,  e.g.  with  the  wooden 
backside  of  the  paint  brush.  Do  not 
touch  the  tape  with  your  fingers,  use 
tweezers instead. 

To  prepare  the  microtome  section,  fold 
down  the  finger  protection  guard  (G) 
and loosen the hand wheel stop (J). 

J 

G 

Turn  clockwise  the  hand  wheel  (K)  on 
the  right  with  your  right  hand  without 
stopping  until  the  specimen  completely 
passed  the  blade,  while  at  the  same 
time  you  keep  holding  the  sectioning 
tape  with  some  tweezers  in  your  left 
hand. 
(NOTE:  If  you  turn  the  hand  wheel  (K) 
anticlockwise,  the  specimen  will  also 
move  5  µm 
you,  not 
backwards.) 

towards 

45 

 
 
 
 
 
 
 
 
The  moment  the  blade  cuts  off  the 
section  of  the  specimen,  tear  off  the 
sectioning  tape  with  the  tweezers  in 
your left hand. To obtain a good section, 
the  cutting  has  to  be  performed  at  a 
continuous, average speed – neither too 
fast,  nor  too  slow.  It  will  need  some 
training  to  find  an  optimum  cutting 
speed and to coordinate all steps. 

G 

J 

Fasten the hand wheel stop (J) and fold 
up the finger protection guard (G) after 
the section. 

The  section  is  acceptable  from  a  first 
glance  when  the  white  strips  cut  off 
from  the  sandwich  plastic  plate  are 
straight,  homogeneous  and  eventual 
knife  marks  (periodic  waves)  are  only 
barely  visible.  Whether  the  section  is 
really  fine,  can  only  be  seen  afterwards 
during the microscopy. 

Prepare the microtome section for microscopy 

If  an  acceptable  section  was  obtained, 
take  a  microscope  slide  and  apply  some 
mounting  medium  with  the  dissecting 
needle. 

Spread  the  mounting  medium  and  put 
the  section  tape  on  it. The  sticky  surface 
of  the  tape  should  face  the  microscope 
slide. Gently press with the wooden shaft 
of  the  paint  brush  to  remove  eventually 
present air bubbles. 

46 

 
 
 
 
 
 
 
 
 
 
     
     
Change the blade 

P 

Q 

Apply  some  more  mounting  medium  on 
top  of  the  sectioning  tape  and  cover 
everything with a cover slip. Again gently 
press  with  the  wooden  shaft  of  the  paint 
brush  to  remove  eventually  present  air 
bubbles. Clean the dissecting needle with 
a paper towel. 

Label  the  microscope  slide  with  the 
sample  name,  date,  thickness  of  the 
section  and  the  initials  of  the  operator 
and  draw  an  arrow  on  the  cover  slip 
pointing  to  the  outside  of  the  multilayer 
sample. 

G 

For changing the blade, refer to the user 
manual  (see  Error!  Reference  source 
ot  found.,  chapter  7.5,  p.  17).  Fold 
down  the  finger  protection  guard  (G) 
and  loosen  the  metal  arm  on  the  left 
(P). 

Push  the  button  (Q)  on  the  left.  The 
blade  will  be  pushed  about  1  cm  out  of 
the  slot  on  the  right  side.  Then  pull  it 
out  completely.  Be  careful  not  to  injure 
yourself when handling the blade! 

There is a compartment for used blades 
in  the  bottom  of  the  blade  dispenser. 
Insert  the  used  blade  there  to  store  it 
safely. 
NOTE: When all blades of the dispenser 
are  finished  (and  the  "used  blades" 
compartment  is  full),  throw  away  the 
entire  dispenser  (incl.  the  used  blades) 
into  a  container  for  contaminated  solid 

47 

 
 
 
 
        
 
 
 
 
 
 
 
      
 
Q 

G 

Clean the microtome after use 

waste  without  opening 
blades" compartment. 

the 

"used 

Take  out  a  new  blade  from  the  upper 
part of the blade dispenser. 

Insert the blade in the blade holder. Use 
the  wooden  shaft  of  the  paint  brush  to 
push it in completely. 

When  finished,  refasten  the  metal  arm 
(Q)  on  the  left  and  fold  up  the  finger 
protection guard (G). 

Clean  the  blade  holder  with  a  dry  paint 
brush and put it back into the plastic box 
for  storage.  Be  careful  again  not  to 
injure yourself while handling the block. 

Remove  the  specimen  and  clean  the 
specimen holder with a dry paint brush. 

Take  a  paper  towel  and  remove  the 
section waste from the waste tray (R). 

R 

48 

 
 
 
 
 
 
 
 
 
 
 
 
 
Troubleshooting 

The following table lists some errors and possible sources of error  

Characteristics of the error 
periodic waves, different thicknesses along 
the section 

Possible origin 
  damaged or blunt knife edge 
 
  elastic sample 
 

improperly or loosely placed knife 

insufficiently fixed sample or sample 
holder 

changing thicknesses along the section 

strongly compressed section 

  sample is too soft 
 

inhomogeneities (i.e. hard and soft 
phases) in the sectioning area 

  wrong trimming 
  wrong knife angle 
  wrongly adjusted free angle (x-z-plane) 
  sample material is too soft 

In  case  of  a  malfunctioning  of  the  instrument,  open  a  non-conformity  in  LAD  and  if 
necessary  require  a  technical  assistance  by  an  external  company  and  register  the 
intervention in LAD. 

Maintenance 

A check of the instrument functions, lubricating of movable parts, a check of the driving 
system  and  a  complete  cleaning  should  be  performed  by  an  authorised  service 
technician when needed. 

Safety 

Blades for microtomes are extremely sharp and need to be handled with care to prevent 
any kind of injury. Please respect the following rules to prevent any injury of yourself or 
other persons in the laboratory when using the rotary microtome: 

  Before installing the blade holder, FIRST install the proper sample holder and 

insert your sample. 

  During use, ALWAYS remove the blade holder BEFORE changing the sample 

holder or the sample. 

  AFTER having finished your work, remove the blade holder and put it back into 

the plastic box for storage. 

References 

Charles W. Scouten, Ph.D., Leica Microsystems (2011). Tips & Tricks in Sample 

Microtome User Manual (SLEE medical GmbH (2014). Operating Instructions – 

[1] 
CUT 4062 / CUT 5062 / CUT 6062) 
[2] 
Preparation. Knife Angle in Microtomy. Retrieved January 19, 2015 from  
http://www.leica-microsystems.com/uploads/media/Knife_Angle_in_Microtomy.pdf 
[3] 
Verlag, p. 213 
[4] 
Springer 

Sawyer LC, Grubb DT, Meyers GF (2008). Polymer microscopy. 3rd edition. 

Michler GH (2008). Electron microscopy of polymers. Berlin/Heidelberg: Springer-

49 

 
 
 
 
 
 
 
 
 
 
Annex  2:  Example  of  protocol  for  microscopy  of  microtome  cross-
sections  

The protocol shown is for polarised light microscopy and digital imaging 

Note:  the  example  given  is  the  one  used  for  JRC  FCM  activities.  It  is  intended  as  an  illustrative 
example only and in no way constitutes a recommendation nor any commercial endorsement. 

Scope and field of application 

This  procedure  describes  how  to  analyse  microtome  cross-sections  of  multilayer  plastic 
laminates  in  plane  and  crossed  polarised  light  using  transmitted  polarised  light 
microscopy (incident light microscope Zeiss Axioskop 2 MAT available in the "PRODUCT 
SAFETY & INNOVATION" group of the CAT Unit, Bld. 26, Lab 023), how to perform digital 
imaging  and  how  to  determine  the  thickness  of  individual  layers.  Strict  respect  of  this 
SOP is required to all operators within FIT-EURL laboratories. 

Equipment 

Incident light microscope 

 

incident  light  microscope:  Zeiss  Axioskop  2  MAT  (SN:  005  007  249),  equipped 
with Moticam 10 (10.0 MP) 

  personal computer: Dell Optiplex 740MT  

  software: Motic Images Plus 2.0 

Other laboratory equipment 

  microscope slide with calibration and scale cross for calibration 

Microscopy 

Set  the  microscope  for  transmitted-light  brightfield  according  to  KÖHLER.  Refer  to  the 
instrument manual (0 section 4.3.6 (3) p. 89-90). 

Switch on the microscope. 

Place  a  high-contrast  specimen  on  the 
specimen  holder  (e.g.  the  calibration 
slide → circle with 0.15 mm diameter). 

NOTE: The calibration slide can be found 
in  one  of  the  drawers  labelled  as 
"Moticam accessories". 

50 

 
 
 
 
 
 
 
 
 
 
Switch  the  turret  disk  of  the  condenser 
to position "H" for brightfield. 

Swing in the 10x object lens and adjust 
the  focus  so  that  the  object  is  clearly 
visible. 

Close the luminous-field diaphragm until 
its  border  becomes  visible  (even  if  not 
in focus) in the field of view. 

Use  drive  to  lower  the  condenser  until 
the 
luminous-field 
diaphragm is in focus. 

edge 

the 

of 

the 
Use  both  centering  screws  of 
universal  condenser 
the 
to  centre 
luminous-field diaphragm and then open 
the  diaphragm  until 
just 
disappears from the field of view. 

its  edge 

51 

 
 
 
 
 
 
 
 
set 

the 

aperture 

To 
diaphragm 
(contrast),  remove  one  eyepiece  from 
the tube (it can be pulled out) and look 
into the tube with your naked eye. 

Calibration of the digital camera 

Use the sliding knob to set the aperture 
diaphragm  to  approx.  2/3  or  4/5  of  the 
diameter  of  the  objective  exit  pupils  as 
described  in  the  instrument  manual  0. 
Insert  the  eyepiece  in  the  tube  again 
when ready. 

Switch on the computer. 

the  microscope 

slide  with 
Take 
calibration  circles  and  scale  cross  and 
place it on the specimen holder. 

NOTE: The calibration slide can be found 
in  one  of  the  drawers  labelled  as 
"Moticam accessories". 

Select  the  object  lens  that  needs  to  be 
calibrated  and  adjust  the  microscope 
focus to view the appropriate calibration 
circle or the scale cross (see Table 10). 

NOTE:  The  calibration  circles  are  more 
suitable  if  round  shaped  items  need  to 
If  cross-sections  of 
be  measured. 
multilayer 
be 
analysed,  it  is  advised  to  perform  the 
calibration using the scale cross. 

plastic 

films 

shall 

52 

 
 
 
 
 
 
 
 
 
 
Table 10 Object lenses and the appropriate calibration circle or scale cross for calibration 

Object lens 

Calibration circle or scale cross 

10x/0.25 Ph1 

scale cross 0.01 mm OR circle Ø 0.15 mm (150 µm) 

20x/0.45 Ph2 

scale cross 0.01 mm OR circle Ø 0.15 mm (150 µm) or 0.07 mm (70 µm) 

40x/0.65 Ph2 

scale cross 0.01 mm OR circle Ø 0.07 mm (70 µm) 

Open  the  software  "Motic  Images  Plus 
2.0". 

Go  to  menu  "File"  and  select  "Capture 
Window". 

A  new  window  ("Motic  Live  Imaging 
Module") will open. 

Pull out the metal bar in the upper part 
of the microscope. Now the live picture 
of  the  camera  (Moticam  10)  can  be 
seen  on  the  screen  (in  the  "Motic  Live 
Imaging Module" window). 

53 

 
 
 
 
 
 
 
 
    
 
the  position  of 

Readjust  the  focus  again  if  necessary 
and  adjust 
the 
microscope  slide  to  see  the  entire 
calibration  circle  or  the  origin  of  the 
scale cross. The calibration circle or the 
origin  of  the  scale  cross,  respectively, 
should  be  in  the  centre  of  the  picture. 
To properly align the scale cross, it may 
the 
be  necessary 
camera. 

to  slightly 

turn 

If  necessary,  change  the  settings  for 
the contrast and sharpness. 

For 

calibrations  using 

NOTE: 
a 
calibration  circle,  a  sufficient  contrast 
between  the  circle  and  the  background 
is  needed.  Otherwise  the  automatic 
calibration  cannot  be  carried  out.  The 
settings shown here in the print screens 
should  be  sufficient.  In  addition,  the 
power  of  the  light  source  on  the 
microscope  should  be  no  higher  than 
"5". 

Then go to the tab "Video Capture" (see 
camera  symbol)  and  click  "Capture"  to 
take a snap shot of the current camera 
view. 

54 

 
 
 
 
 
 
 
files 

Each  snap  shot  is  saved  automatically 
and  can  be  seen  on  the  right  in  the 
window  "Motic  Images  Plus  2.0  ML". 
as 
The 
"Capture_xx.sfc"  with  numbers 
in 
chronological  order.  They  can  be  found 
in  the  folder  C:\Motic\Motic  Images 
Plus 2.0\Capture Folder. 

named 

are 

all 

Calibration with calibration circle 

NOTE:  Do  not  change  the  position  of 
the camera after having taken the snap 
shot  for  calibration.  Otherwise  a  new 
snap  shot  should  be  taken  to  carry  out 
the calibration. 

Go  to  window  "Motic  Images  Plus  2.0 
ML". Open the menu "Measure". Select 
"Calibration Wizard". 

The  window  "Calibration  Wizard"  will 
open.  Go 
tab  "Calibrate  with 
calibration  circle"  and  click  the  button 
"Load Image". 

to 

55 

 
 
 
 
 
 
 
A  dialog  box  opens.  Select  the  snap 
shot  file  of  the  calibration  circle  that 
you  want  to  use  for  calibration  and 
click "Open". 

NOTE:  All  snap  shots  taken  before  can 
be  found  in  the  folder  C:\Motic\Motic 
Images Plus 2.0\Capture Folder. 

the  diameter  [µm]  of 

Enter 
the 
selected  calibration  circle  and  specify 
the  object  lens  (e.g.  10x,  20x  or  40x) 
with  which  the  snap  shot  was  taken. 
Then  click  the  button  "Calibration"  and 
the calibration is done automatically. 

A  new  window  "Save  Sign"  will  open. 
Select  a  "Sign  Name"  from  the  column 
on the left (e.g. "40X (object lens)") or 
define a new one. Then click the button 
"Save". 

The calibration is finished now and you 
can  close  the  "Calibration  Wizard" 
window by clicking the button "Close". 

56 

 
 
 
 
 
 
 
 
Calibration with scale cross 

Go  to  window  "Motic  Images  Plus  2.0 
ML".  Open 
the  menu  "Measure". 
Select "Calibration Wizard". 

The  window  "Calibration  Wizard"  will 
open.  Go  to  tab  "Calibrate  with  scale 
cross"  and  click  the  button  "Load 
Image". 

A  dialog  box  opens.  Select  the  snap 
shot  file  of  the  scale  cross  that  you 
want  to  use  for  calibration  and  click 
"Open". 

NOTE: All snap shots taken before can 
be  found  in  the  folder  C:\Motic\Motic 
Images Plus 2.0\Capture Folder. 

The  selected  photo  will  be  opened  in 
the  "Calibration  Wizard"  window.  Use 
the scroll bars on the right and on the 
bottom  to  move  to  the  centre  of  the 
photo.  There  you  will  find  a  white 
circle  with  two  red  dots  and  a  dialog 
box that shows the current dimension 
of the white circle. 

57 

 
 
 
 
 
 
 
 
B 

A 

B 

A 

The  circle  must  be  positioned  in  the 
very centre (origin) of the scale cross. 
If  necessary,  reposition  it.  To  do  so, 
move  the  cursor  above  the  white 
circle. The cursor will transform into a 
cross. Now click on the circle with the 
left  mouse  button  and  drag  and  drop 
it. 

Move  the  cursor  to  the  upper  red  dot 
(B).  The  cursor  will  transform  into  a 
hand.  Now  click  on  the  red  dot  (B), 
drag  it  along  the  y-axis  of  the  scale 
cross  and  drop  it  exactly  at  a  certain 
scale  division/bar  (e.g.  5  bars  =  0.05 
mm  =  50  µm  away  from  the  origin). 
The circle will deform into an ellipse. 

Then move the cursor to the right red 
dot  (A).  Again 
the  cursor  will 
transform  into  a  hand.  Click  on  the 
red  dot  (A),  drag  it  along  the  x-axis 
of  the  scale  cross  and  drop  it  exactly 
at a certain scale division/bar. Use the 
same distance as before at the y-axis 
(e.g.  5  bars  =  0.05  mm  =  50  µm 
away from the origin). 

If you positioned each of the red dots 
(A,  B)  with  the  same  distance  to  the 
origin  of  the  scale  cross,  the  pixel 
number  for  the  x-  and  y-dimension 
("Major/Minor  half  axis")  of  the  circle 
must be the same. If not, readjust the 
positions  of  the  red  dots.  Sometimes 
it  can  be  necessary  to  reposition/re-
centre the entire circle. 

Specify the  object lens (e.g. 10x, 20x 
or 40x) with which the snap shot was 
taken and enter the x,y-dimensions of 
the  circle.  "Width"  and  "Height"  refer 

58 

 
 
 
 
 
 
 
 
 
 and  𝑂𝐵̅̅̅̅

the  distance  𝑂𝐴̅̅̅̅

, 
to 
respectively, with "O" being the origin 
of  the  circle.  In  the  present  example, 
the  dots  were  positioned  5  bars  (50 
the  origin  (O). 
µm)  away 
"Width" (𝑂𝐴̅̅̅̅) and "Height" (𝑂𝐵̅̅̅̅) of the 
circle are then 50 µm each. Then click 
the button "Calibration". 

from 

A  new  window  "Save  Sign"  will  open. 
Select a "Sign Name" from the column 
on  the  left  (e.g.  "40X  (object  lens)") 
or  define  a  new  one.  Then  click  the 
button "Save". 

The  calibration  is  finished  now  and 
you can close the "Calibration Wizard" 
window by clicking the button "Close". 

Set the microscope for transmitted-light polarisation 

Refer to the instrument manual (0 section 4.3.9.1 (3) p. 96). 

Take  the  microscope  slide  with  the 
microtome  section  of  the  sample  and 
place it on the specimen holder. 

59 

 
 
 
 
 
 
 
 
Push back in the metal bar to be able to 
view  the  sample  in  the  eyepiece  of  the 
microscope. 

Adjust  the  focus  so  that  the  sample  is 
clearly 
sufficient 
magnification use the 40x object lens. 

visible. 

For 

sample in crossed polarised light: 

To  view  the  object  in  plane  polarised 
light,  swing  the  polariser  in  the  beam 
path. 

To  view  the  object  in  crossed  polarised 
light,  swing  in  the  analyser  module 
(filter  No.  2  "Epi  Pol")  on  the  reflector 
turret in addition.  

The  field  of  view  will  appear  dark  now 
because the polarisers are crossed. Only 
birefringent  (i.e.  anisotropic)  objects 
(e.g.  polymer 
films  where  polymer 
chains  have  an  orientation,  e.g.  due  to 
shear  stress  in  the  die  or  due  to 
stretching  during  extrusion)  will  display 
a colour now (white or brightly coloured) 
(see 0, 0). 

NOTE:  Anisotropic  materials  may  also 
remain  dark  between  crossed  polars  if 
the sample is oriented so that it is being 

60 

 
 
 
 
 
 
 
 
 
sample in plane-polarised light: 

sample in crossed polarised light: 

viewed down an optic axis and therefore 
appears isotropic or the sample is in one 
of  4  possible  extinction  positions  (see 
0).  If  this  happens,  microscopy  should 
be carried out in plane-polarised light. It 
is  not  possible  to  make  the  specimen 
visible by rotating the specimen itself or 
the  direction  of 
by  changing 
the 
the  polariser 
rotating 
polarised  by 
because the microscope is equipped with 
a  non-rotatable  mechanical  stage  and  a 
non-rotatable polariser/analyser. 

sample in plane-polarised light: 

Carefully  "scan"  the  entire  microtome 
section from head to tail. It may happen 
that  certain  parts  are  damaged  and  one 
or more of the sample layers can be de-
laminated.  Try  to  find  an  intact  part  of 
the  section  to  continue.  Otherwise  you 
have to prepare a new section. 

Take a digital image of the sample 

Pull out the metal bar in the upper part of 
the  microscope.  Now  the  live  picture  of 
the camera (Moticam 10) can be seen on 
the  screen  (in  the  "Motic  Live  Imaging 
Module" window). 

61 

 
 
 
 
 
 
 
 
 
 
    
 
sample in crossed polarised light: 

sample in plane-polarised light: 

the  position  of 

Readjust  the  focus  again  if  necessary 
the 
and  adjust 
microscope slide to see all the layers of 
the  sample  in  the  live  picture  on  the 
screen.  Go  to  the  tab  "Video  Capture" 
(see 
click 
"Capture"  to  take  a  snap  shot  of  the 
current camera view. 

symbol) 

camera 

and 

files 

Each  snap  shot  is  saved  automatically 
and  can  be  seen  on  the  right  in  the 
window  "Motic  Images  Plus  2.0  ML". 
as 
The 
in 
"Capture_xx.sfc"  with  numbers 
chronological  order.  They  can  be  found 
in the folder C:\Motic\Motic Images Plus 
2.0\Capture Folder. 

named 

are 

all 

Measure the sample dimensions in the digital image 

62 

 
 
 
 
 
 
 
 
 
Go  to  the  window  "Motic  Images  Plus 
2.0  ML"  and  load  an  image.  You  can 
either  select  one  of  the  photos  taken 
before  from  the  right  side  of  the 
window  or  load  an  image  from  a  file. 
IN  the  latter  case,  open  the  menu 
"File" and select "Open". 

A  new  window  will  open.  Select  a  file 
and click the button "Open" to open it. 

Select  the  correct  object  lens  that  was 
used  to  take  the  image.  Open  the  tab 
"Measure"  on  the  lower  left  of  the 
window  and  select  an  object  lens  from 
the drop-down menu. 

NOTE: The object lens must have been 
calibrated  before  as  described 
in 
section  0.  Select  the  object  lens  name 
from  the  list  that  was  used  in  the 
calibration (here "40X (object lens)"). 

63 

 
 
 
 
 
 
 
 
the  picture,  open 

To measure the thickness of the layers 
in 
the  menu 
"Measure"  on  the  upper  left  of  the 
window  and  select  "Line"  from  the 
drop-down menu. 

You  can  draw  a  line  now.  To  do  so, 
click  and  hold  the  left  mouse  button 
while  dragging  the  line.  The  length  of 
the line will be shown immediately in a 
small text box. 

NOTE:  If  necessary,  move  the  scroll 
bars  on  the  right  and  the  bottom  to 
select the area of the image where you 
want to carry out the measurements. 

Start  and  end  point  of  the  line  can  be 
readjusted. Simply click on the start or 
end  point  with  the  left  mouse  button 
and  drag  and  drop  the  point.  Like  this 
you  can  also  elongate  a  line  if  the 
measurement  area  is  bigger  than  the 
actual area shown on the screen. 

Also  the  entire  line  as  well  as  the  text 
box  can  be  moved  via  drag  and  drop 
with the left mouse button. 

The  measurement  should  be  carried 
out perpendicular to the layers. 

● 

64 

 
 
 
 
 
 
 
 
 
If  you  want  to  add  more  lines,  just 
click  and  hold  the  left  mouse  button 
and  draw  the  line  as  described  before. 
There is no need to activate the "Line" 
function again in the "Measure" menu. 

A  table  that  lists  the  dimensions  of  all 
lines  drawn  can  be  accessed  via  the 
button  "Measure  Table"  in  the  lower 
left 
tab 
"Measure". 

corner  of 

screen, 

the 

A new  window ("Measure") opens. The 
tab "Measure Tables" shows the length 
of each drawn line. 

In  the  tab  "Options"  the  line  style  and 
the  format  of  the  text  boxes  can  be 
changed. 

When  you  are  finished,  save  the  file. 
To  do  so,  open  the  drop-down  menu 
"File"  in  the  upper  left  corner  of  the 
screen and select "Save As". 

65 

 
 
 
 
 
 
 
 
 
A  new  window  ("Save  Image")  will 
open. It is advised to save the file as a 
"sfc"-project  which  can  be  reworked  if 
necessary.  If  you  want  to  export  it, 
it  also  as  a  "tif"-file  which 
save 
provides  a  sufficient  resolution 
for 
publication 
in  reports  or  scientific 
journals.  Never  overwrite  the  original 
file  "Capture_xx.sfc".  Always  select  a 
new  file  name.  You  can  also  create  a 
new  folder  for  your  project  and  save 
the files in the project folder. 

Reference documents 

[1] Carl Zeiss Light Microscopy (2002).  Operating Manual. Axioskop 2 MAT/2 MAT mot. 

Incident Light Microscope. B 46-0012 e 10/02 

[2] Zhang XM, Elkoun S, Ajji A, Huneault MA (2004). Oriented structure and anisotropy 
properties of polymer blown films: HDPE, LLDPE and LDPE. Polymer 45: 217-229 

[3] Sawyer LC, Grubb DT, Meyers GF (2008). Polymer microscopy. 3rd edition. Springer 

66 

 
 
 
 
 
 
 
Annex 3: Example of protocol for handling/maintenance of an ATR-FTIR 
spectrometer 

Note:  the  example  given  is  the  one  used  for  JRC  FCM  activities.  It  is  intended  as  an  illustrative 
example only and in no way constitutes a recommendation nor any commercial endorsement. 

Scope and field of application 

This procedure describes how to perform ATR-FTIR spectroscopy to characterise liquid or 
solid substances (e.g. polymer films). 

Terms and definitions 

ATR 

attenuated total reflection --  FTIR  Fourier Transform Infrared 

Materials and reagents 

  organic solvent (e.g. acetone) to clean the ATR diamond crystal 

  paper towels 

Equipment 

ATR-FTIR system 

  Perkin  Elmer  Spectrum  One  FT-IR  Spectrometer  equipped  with  Perkin  Elmer 

Universal ATR Sampling Accessory  

  personal  computer:  Dell  Optiplex  GX270  software:  Spectrum  Version  6.3.1, 

Perkin Elmer 

Other laboratory equipment 

 

tweezers 

  Pasteur pipettes 

  glass beaker (25-50 mL) 

  spatula 

ATR-FTIR Spectroscopy 

Start up 

  Switch  on  the  computer  and  monitor.  The  ATR-FTIR  spectrometer  should  be 

already turned on as it is kept ON at any time. 

  Open the software "Spectrum" (Version 6.3.1) and log in  

  Check  the  intensity  of  the  laser  beam  as  described  in  the  user's  guide  for  the 
"Spectrum"  software.  If  the  criteria  are  not  met,  refer  to  the  troubleshooting 
section of the instrument manual 0. 

  Confirm  that  the  ATR  crystal  is  clean  and  collect  a  background  spectrum  for  air 
without  any  sample.  To  do  so,  proceed  as  indicated  in  the  "Spectrum"  software 
user's guide 0. 

Collecting sample spectra 

67 

 
 
 
 
 
 
 
 
 
  Collect sample spectra according to the "Spectrum" software user's guide 0. 

  Avoid any scratching of the ATR  crystal when installing a test specimen. Lift the 
plunger  well  up  before  moving  it  to  avoid  scratching  the  ATR  crystal  and  the 
surrounding metal plate. When installing the specimen, never fasten the plunger 
too tight. Otherwise the ATR crystal may break. 

Data processing 

  Perform  data  processing,  such  as  baseline  correction,  smoothing,  subtraction  or 
labelling of spectra, as needed. Refer to the "Spectrum" software user's guide and 
proceed as indicated in there 0. 

  Files  of  all 

recorded  spectra  are  saved  automatically 

folder 
C:\pel_data\spectra.  You  can  create  an  additional  folder  for  your  project  and 
move  all  files  there.  Indicate  the  data  path  in  the  instrument  table  (Annex  1). 
Save also your processed files if wanted under this data path. 

the 

in 

Shut down 

  Fill in the instrument table 

  Shut down the computer and switch off the monitor. 

  DO NOT SWITCH OFF THE ATR-FTIR SPECTROMETER. The instrument should 
remain ON at all times. This keeps it stable and prevents excessive accumulation 
of water which might damage the beam splitter. 

Troubleshooting 

For troubleshooting refer to the instrument manual 0 or the software user's guide 0. 

Cleaning and maintenance 

  Clean  the  ATR  crystal  and  the  plunger  with  a  paper  towel  soaked  in  an  organic 
solvent (e.g. acetone) after use. DO NOT SCRATCH THE CRYSTAL SURFACE! 

 

In  case  of  errors,  problems  or  general  maintenance  consult  the  instrument 
manual 0. 

  The  desiccant  inside  the  instrument  has  to  be  removed  and  dried  once  every 

year. To do so, proceed as indicated in the instrument manual 0. 

  For extraordinary maintenance, contact an authorised service technician. 

  Register all errors, problems and maintenance activities in the instrument table  

Safety 

The  instrument  contains  a  low  power,  visible  (red)  laser.  Do  not  stare  into  the  laser 
beam to prevent damage of your eye. 

Reference document 

[1] Perkin Elmer. Spectrum One. Instrument Manual 

[2] Perkin Elmer. IR Spectroscopy Software User's Guide 

68 

 
 
 
 
 
 
 
 
 
Europe Direct is a service to help you find answers to your questions about the European Union 
Free phone number (*): 00 800 6 7 8 9 10 11 
(*) Certain mobile telephone operators do not allow access to 00 800 numbers or these calls may be billed. 

A great deal of additional information on the European Union is available on the Internet. 
It can be accessed through the Europa server http://europa.eu 

How to obtain EU publications 

Our publications are available from EU Bookshop (http://bookshop.europa.eu), 
where you can place an order with the sales agent of your choice. 

The Publications Office has a worldwide network of sales agents. 
You can obtain their contact details by sending a fax to (352) 29 29-42758. 

69 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
L
B
-
N
A
-
2
7
8
1
6
-
E
N
-
N

JRC Mission 

As the Commission’s  
in-house science service,  
the Joint Research Centre’s  
mission is to provide EU  
policies with independent,  
evidence-based scientific  
and technical support  
throughout the whole  
policy cycle. 

Working in close  
cooperation with policy  
Directorates-General,  
the JRC addresses key  
societal challenges while  
stimulating innovation  
through developing  
new methods, tools  
and standards, and sharing  
its know-how with  
the Member States,  
the scientific community  
and international partners. 

Serving society  
Stimulating innovation  
Supporting legislation 

doi:10.2788/10593 

ISBN 978-92-79-57561-7 

70