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Release Coatsby
Jimmy Lampley
April, 08
Definition of Release Coat
What is a “release coat?”…..A
coat/coating that will relieve,
liberate, release, or free (as from
restraint) when desired/ required.
Release Coat Schematic
Release Coat
Substrate: Treated(Corona/chemical/primer)
Roll of tape Adhesive
Types of Adhesive
Hot melt
Natural Rubber
SIS, SBS
Acrylate
Others
Substrates
Films: PE, PP, PET, PVC, Acetate,
Perforated PE, Nonwoven
PET
Paper
Foil
Cloth: Plain, PE coated
Release Coats Types
Silicone
Non-silicone
Non-Silicone
WATER
Polyurethane
Urethane-Acrylic
Fluoro-polymer
PET/acrylic
Vinylacetate/Acrylic
Polysaccharide
SOLVENT
PVODC
PVSC
Polyethylenimine
Octadecyl Carbamate
(PEIODC)
Types of Release Coat
Type Acrylate Carbamate Silicone
Release
Level
1.0-1.5N/c 0.1-0.7N/c 0.01-0.1N/c
9-21 oz/in 1-6.5 oz/in 0.1-1 oz/in
Chemical
Name Fluorochemical PVODC Silicone
Types of Application
Engraved Cylinder (rotogravure)
Meyer Rod
Reverse Doctor Blade
Flexo
Need treatment (corona/chemical/primer)
Curing/Drying
Must dry web of solvent or water
Reach a temperature to remove fully the
solvent or water
Most release coats must also reach a specific
temperature to set, or film form
Web temperature/not air temperature
Assure the drying oven is free of obstructions
Film Forming Temperatures
Release Coat Temp., C Temp., F
Polyurethane 100 212
Ure-Acrylic Dry of water Dry of water
PET/Acrylic 100 212
Vinylacetate/acrylic 145 300
Polysaccharid Dry of water Dry of water
Film Forming Temperatures
Release Coat Temp., C Temp., F
Fluorpolymer, RA-110W 138 280
Fluorpolymer, RA-120W Dry of water Dry of water
PVODC 80-92 176-196
PVSC >80 >176
PEIODC Approx. 90 Approx. 190
General Properties of Release Coats
Liquid vs Powder
Water-blended vs Solvent-blended
A specific level of release, i.e. N/cm or Oz/in
Any FDA requirements
Long shelf life
Aging at elevated temperature & humidity
Chemistries
� PVODC
� PVSC
� PEIODC
Carbamate Release Coat Chemistry
Polyvinyl
Alcohol
Octadecyl
Isocyanate
O
H
Polyvinyl
Octadecyl Carbamate
CH2–CH–CH2–CH n
O–C–N–C18H35
H
+ C18H35N=C=OCH2–CH
OHn
OH
Carbamate Release Coat Chemistry
CH2–CH
OHn
+C18H37N=C=O
Polyvinyl
Alcohol
Octadecyl Isocyanate
Hexadecylisocyanate
CH2–CH–CH2–CH n
O–C–N–C18/16H35
HO
H
Polyvinyl
Stearyl Carbamate
OH
C16H37N=C=O
Carbamate Release Coat Chemistry
[H2N-(CH2–CH2N)x
CH2CH2NH2
+ C18H37N=C=O
Poly-Ethylenimine
Octadecyl IsocyanatePolyethylenimine
Octadecyl Carbamate
-(CH2CH2NH)y]
Pyridine
(C19H37NOC2H5N)X
(CH2-CH2N)n
PV
SC
PV
OD
C
PE
IOD
CSolubility
Melt Point
Anchorage
Film Forming Temp
Per
form
an
ce D
iffe
ren
ces
Per
form
an
ce D
iffe
ren
ces
PV
SC
PV
OD
C
PE
IOD
CSolubility
Melt Point
Anchorage
Film Forming Temp
Cloud Point vs. Solvent
0.3 0.5 0.7 1 1.5
100% Toluene 15% Toluene/85% Heptane
Tem
pera
ture
Release Coat Solution % Solids
% M
ax
imu
mR
elease
0%
20%
40%
60%
80%
100%
0.1 0.2 0.5 1 1.5 2 3
% Solids Release Coat
Proper Film Forming Temperature Reached
Release Coat Weight vs.% Maximum Release
Coat Weight vs. Maximum Release
0
20
40
60
80
100
0.1 0.2 0.5 1 1.5 2 3
Proper Film Forming Temperature NOT Reached
% M
axim
um
Relea
se
% Solids Release Coat
Release Coat Use Questions
Oven Drying Capabilites (What web temp.
can be obtained?)
Recirculation equipment
Temperature requirements
Printable or not (What kinds of inks or with
pencil/pen?)
Foaming issues (with water based)
Water-Based Release Coat
Preferred Emulsion
Polymer system
R
RR
R
R
R
Water-Based Release Coat
Relative Release Values
0
100
200
300
400
500
600
700
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Relative Amount of Release
Pu
ll S
tren
gth
Valu
e
A ll S ilic o ne Vinyla c e ta te / a c rylic Ure tha ne -A c rylic A c rylic
Water-Based Release Coat
Relative Release Values
0
100
200
300
400
500
600
700
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Relative Amount of Release
Pu
ll S
tre
ng
th V
alu
e
Vinyla c e ta te / a c rylic Ure tha ne -A c rylic
Escoat WFX 120
Escoat WPM80
RA-130W
