TECHNICAL INFORMATION
ADDITIVES FOR PVC PLASTISOL APPLICATIONSPVC-TI 8

02

Additives for PVC plastisol applications

Contents
03 Introduction

22 Processing additives

04 Viscosity depressants

25	
Additives to increase electrical

08 Wetting and dispersing additives
11 Air release additives
13 Rheology additives
18 Moisture absorbers
20 Foam stabilizers for mechanical foams

conductivity
26	Additives to increase the surface energy
after gelling

03

Introduction
PVC plastisols are used in numerous applications, ranging
from floorings and wall coverings, vinyl, printing inks, andtextile applications to dip coatings, tarps, and traffic cones.
Our corresponding additive portfolio supports the production
processes and helps optimize material properties.

Note
To ensure the best appearance
and full functionality, please
open in Adobe Acrobat.

04

Additives for PVC plastisol applications

Viscosity depressants
Shear rate calculation example

Why use viscosity depressants?
It is important to adjust the viscosity for each type of
manufacturing process. This ensures consistent processing
and high product quality.
Viscosity (η) is the key factor in describing flow behavior. In
most plastisol systems, viscosity is not a constant. It depends
on a variety of parameters. To a great extent, it determines
the usability and user-friendliness of the PVC plastisol.

The three most important factors encountered in PVC
plastisol formulating are:

Shear rate =1. Raw material properties
2. Temperature parameters
3. Rheology.

Line speed x Conversion factor
Coating gap

Speed
Coating gap
Conversion factor

25 m/min
0.1 mm
~ 16.782 ft/min
2.5 mils~ 127

Shear rate =25 x 16.7
0.1

82 x 127
2.5~ 4170 s -1

~ 4170 s -1

Rheology is the interrelationship between viscosity and shear
forces, which can be very complex.
The most important rheological parameter from theapplication standpoint is the mechanical stress the liquid
system is exposed to.

Typical shear ranges

Shear rate dependent on coating gap
Shear rate (s-1)
17500

Storage

15000

Pumping, stirring, mixing

Transport

12500

Settling

10000

Spraying

Knife, roll coating
Sagging
leveling

7500
5000
2500
0

0.001

0.01

0.1

1

10

100

1000

10 000100 000

0.5

0.4

0.3

G. 01

0.2

0.1

0.05

Coating gap (mm)s -1Line speed (m/min)  

10

25

50

G. 02

05

Additives for PVC plastisol applications / Viscosity depressants

Volatility behavior

How do viscosity depressants work?

Product volatility

BYK’s viscosity depressants work in two steps:

Additives of the VISCOBYK-5000 series and BYK-1160
series are low-volatile viscosity depressants. During
production, the process emissions are reduced significantly
compared to conventional viscosity depressants (G. 05).
These additives perform similarly to primary plasticizers inregard to their low volatility.

1. The mixtures of aliphatic hydrocarbons or carboxylic
derivatives are specially developed to reduce the viscosity
in the liquid phase of the PVC plastisol.
2. The special wetting and dispersing components adsorb
onto the particle surfaces, reducing the interactive forces
between them and preventing reagglomeration.

Volatility (%) at 200 °C
100
80
60
40
20
0

Viscosity depressants allow for easier movement of theparticles. This stabilizes the viscosity and storage behavior of
the whole system (G. 04).

0

1

2

3

Time (min)Conventional viscosity depressants and secondary plasticizers
VISCOBYK 5000 series and BYK-1160 series

Plastisol without viscosity depressants

PVC resin

SolidInteractive forces

5

4

G. 05

Primary plasticizer

Plastisol with viscosity depressants

G. 03

PVC resin

G. 04

Solid

Wetting and dispersing additive

Aliphatic hydrocarbons/carboxylic acid derivatives

06

Additives for PVC plastisol applications / Viscosity depressantsEmission test methods
FLEC test (field laboratory
emission cell)
FLEC is a small piece of equipmentthat is easy to handle and easy toclean. It was designed to measure
VOC emitted from smooth andeven surfaces. It can be used foremission testing in the laboratory
and at building sites. The FLEC
system is widely used due to its
measurement flexibility.

To determine the VOC (volatile organic compounds) ofbuilding materials (e.g. cushion vinyl floorings), theanalytical laboratory of BYK uses the following
instrumentation:

Nord test (chamber method)
This test specifies a procedure forthe determination of VOC emissions
from building materials in a small,ventilated climate.

Flow chart of VOC measurement

43With both types of test equipment, the sample material’semissions are collected in a Tenax tube (G. 06). The quantityand quality can be determined by the use of analyticalequipment, such as the gas chromatograph and mass
spectrophotometer.
The air velocity over the test material’s surface area can be
50 to 100 times greater with the FLEC equipment than with
the Chamber method.

6
1 Test sample
2 Synthetic air

1

2

3 Water57

4 50% RH
5 Tenax tube
6 Chamber
7 FLEC

1
G. 06

07

Additives for PVC plastisol applications / Viscosity depressants

Additive recommendations
Overview of BYK additives for viscosity reduction

Highly filled plastisols

Unfilled to highly filled plastisols

Low/medium shear rate

Medium/high shear rate

BYK-1165
DISPERBYK-102

Viscosity
reduction
and wetting

Viscosity
reduction

VISCOBYK series
4000 – conventional
5000 – low emission

Viscosity
reduction
Low/medium shear rate

BYK-1160
BYK-1163
BYK-1164
BYK-1166

Unfilled to medium-filled plastisols,
PVC resin-specificLow shear rate

Viscosity
reduction
and wetting

Wettinganddispersing

DISPERPLAST-1142
DISPERPLAST-1148
DISPERPLAST-1150

Filled and pigmented plastisols

G. 07

08

Additives for PVC plastisol applications

Wetting and dispersing additives
Why use wetting and dispersing additives?
Wetting and dispersing additives correct the deficiencies
that occur during the dispersion process. During thedispersion of particles in plasticizers, the interactive forces
between the particles result in long dispersion times,
pigment streaks, flooding and floating, and high viscosity.

stabilized, the finely distributed particles reagglomerate andform flocculates (G. 08). Wetting and dispersing additives
adsorb onto the surface of the pigment/filler particles. They
then separate particles from each other and stabilize thesystem by forming an organic adsorption layer that iscompatible with the plasticizers.

During dispersion, the introduction of energy breaks down
agglomerates into individual particles. If the system is not

Dispersion process
Agglomerate

Primary particles (ideal dispersion)

Dispersion

Flocculation

Flocculated

Deflocculated
G. 08

Benefits of wetting anddispersing additives• Reduced flooding and floating• Improved flow behavior• Improved glass/synthetic fiber
penetration/wetting• Higher pigment loading at
lower/constant viscosity• Shorter dispersion times• Increased throughput• Improved color consistencyfrom batch to batch• Faster color matching• Greater color strength andhiding power• Longer storage stability ofdispersions

09

Additives for PVC plastisol applications / Wetting and dispersing additives

Viscosity reduction of a foamed
wallcovering plastisol

Better penetration of glass fibers using DISPERPLAST-1142

Black colored plastisol
without additive

Black colored plastisol
with DISPERPLAST-1142

Viscosity (mPa·s)

Glass fibers totally
impregnated20000

Formulation:

18000

100.0 pts PVC

16000

65.0 pts Plasticizer

14000

70.0 pts CaCO3

12000

20.0 pts TiO2

10000

4.0 pts Azodicarbonamide

8000

3.0 pts Liquid kicker

6000

6.0 pts VISCOBYK

4000

0.6 pts DISPERPLAST

2000

Glass fibers
still visible

0

Brookfield

Haake

Göttfert
Shear rate

G. 09

Better handling with increased pigment loading using DISPERPLAST-1150

50 % TiO2 in plasticizer
without additive

70 % TiO2 in plasticizerwith DISPERPLAST-1150

Control

G. 11

DISPERPLAST

Viscosity reduction of a highly filledplastisol (e.g. carpet backing)Viscosity (mPa·s)

Pourable andpumpable

125000

Formulation:
100.0 pts PVC

100000

Brookfield DV2

250.0 pts CaCO3

75000

0.8 pts BYK-2616
3.2 pts Carbon black paste

50000

1.0 pts Stabilizer
1.0 pts BYK-1165

25000
0

Not pumpable

70.0 pts Plasticizer

2.5 rpm

20 rpm50 rpmShear rate

G. 10

Control

BYK-1165

G. 12

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Additives for PVC plastisol applications / Wetting and dispersing additives

Viscosity reduction of a CaCO3 paste withDISPERPLAST-1148 in plasticizer

Without additive

Viscosity reduction of a carbon black paste
using DISPERBYK-2157

With DISPERPLAST-1148

Without additive

With DISPERBYK-2157

G. 14

G. 13

Additive recommendations
Product

Inorganic pigments

Organic pigments

Carbon blacks

Azodicarbonamide

BYK-1162

Low fogging



BYK-1165



BYK-9076



Dispersing medium

BYK-9077



DISPERBYK-102



DISPERBYK-2157



DISPERPLAST-1142



DISPERPLAST-1148



DISPERPLAST-1150



DISPERPLAST-IDISPERPLAST-P Recommended  Suitable

Low emission

















































T. 01

11

Additives for PVC plastisol applications

Air release additives
Why use air release additives?

How do air release additives work?

Air entrapment is unavoidable during the production andprocessing of PVC plastisols. Interfacially active substances,e.g. residual emulsifiers, stabilized air bubbles, or the air
release can be inhibited by high viscosity, pseudoplasticity,or thixotropy. However, air bubbles are detrimental to:

BYK’s air release additives work in three steps:• Transparency• Color strength• Print definition• Substrate wetting• Mechanical properties, such as tensile strengthand elongation• Contact drum gelling

1. Displacement of air from PVC resin, filler, pigment,
and reinforcement
By reducing the interfacial tension between plasticizer, PVC
resin, pigment, filler, and reinforcement, the trapped air isdisplaced into the plasticizer.

3. Bubbles burst on the surface
Bubble-stabilizing substances are displaced, and the bubbles
burst.

2. Smaller bubbles coalesce to form larger bubbles
Bubble-stabilizing substances are displaced by the air release
additive. Smaller bubbles coalesce to form larger bubbles,
which rise to the surface faster because of their higher
buoyancy (Stokes’ law).

Air release additives work in three steps
Step 1

Step 2

Step 1

Step 3

Step 2

Step 3

G. 15

12Additives for PVC plastisol applications / Air release additives

Test methods
Additive recommendations
1. Vacuum deaeration
Air is mixed into a PVC plastisol using a Dispermat before
the beaker is put into a desiccator. Full vacuum is pulled
without stirring until the foam reaches the top of the
beaker. Then the vacuum is cut (1 cycle). The number ofcycles and time required for full plastisol deaeration ismeasured.
2. Self deaeration
Air is mixed into a plastisol and stored for a defined time.
Then the plastisol is applied by a doctor blade onto acontrast chart, gelled, and visually checked for bubbles(G. 16).

BYK-3155 and BYK-3140 are the most universal of the BYK
air release additives. BYK-3105 and BYK-3140 are also
recommended for low-fogging applications.
Remarks
To achieve further improvement in defoaming, a combinationof an air release additive and a defoamer (e.g. BYK-A 530)
is recommended.

Vacuumdeaeration

Self deaeration effectWithout additive

With BYK additive

Additive recommendations
Product

Transparent

FilledLow emission

Low fogging

BYK-1160











BYK-1163











BYK-1164









BYK-1166









BYK-3105











BYK-3140











BYK-3155









BYK-A 530









 Recommended  Suitable
G. 16

Foamed


T. 02

13

Additives for PVC plastisol applications

Rheology additives
Why use rheology additives?
Flow behavior is one of the most important technicalproperties of a PVC plastisol. To a great extent, it determines
the usability and user-friendliness of the paste. In plastisols,
thickeners such as fumed silica, polysulfonates, andprecipitated calcium carbonate have traditionally been used.

The rheological behavior of a PVC plastisol using a BYK
rheology additive will depend on the following:
1. Polarity and amount of the emulsifiers and surfactants on
the PVC resin
2. Polarity of the plasticizer type and content
3. The type and amount of solids (e.g. filler, pigment, etc.)
4. Other ingredients (e.g. stabilizer, additives)

An additional major factor for the rheological behavior,
however, is the dependence of viscosity on the shear rate.
For many PVC plastisol applications, a relatively larger shear
range must be considered. A rheological characterization
over the entire shear range is best obtained by means ofrotational viscometers.

These conventional thickeners may exhibit the following
undesirable properties and limitations:• Difficult to store and handle• Hard to disperse properly• High viscosity at high shear rates, which can lead tocoating defects (e.g.: “spitting”) during knife coating andspraying• Poor air release due to highly pseudoplastic rheology• Non-reproducible results• Insufficient heat sag resistance• Loss of thickening effect when used with an amine
adhesion promoter.

Working mechanism of BYK’s rheology additives
Incorporation

Network formation

Viscosity reduction
through shear

Reversible

BYK’s unique rheology additives allow optimum adjustmentof rheological properties. In many cases, the additives areused to improve anti-settling properties during storage
and to avoid sagging during application. In addition, they
reduce flooding and floating of pigmented PVC plastisols
by increasing the yield point.

G. 17

14

Additives for PVC plastisol applications / Rheology additives

Shear rates of typical applications/procedures
Viscosity η (Pa·s)
Low shear forces

Medium shear forcesHigh shear forces

100

StorageTransportation

Leveling

Production
Can viscosity under stirring

Settling

Application

Sagging
Rheometer
Brookfield
Flow cup 4 mm
Krebs-Stormer

ICI cone/plate

Control
0.01
0.001

0.01

0.1

1

10

100

1,000

10,000
Shear rate(s -1)
G.18

Depending on the additive and the concentration used, it ispossible to create a rheology profile that is optimum for the
final product. The important thing is to specifically define
this profile. G. 18 shows the shear rate ranges for different
industrial process steps.

15

Additives for PVC plastisol applications / Rheology additives

Structure of the RHEOBYK-410 series

RHEOBYK-410

Urea groups   

G. 19

Medium polar modifying groups

Structure of RHEOBYK-7590

RHEOBYK-7590

Hydroxy groups  

G. 20

Low polar parts

Structure of the GARAMITE series
Two types of minerals are
mixed to create a uniqueperforming clay-based
additive with much faster/easier processing properties
and that is suitable forsolvent-free, high-viscous
systems

G. 21

16

Additives for PVC plastisol applications / Rheology additives

Comparison of the flow behavior of different rheology additives for PVC plastisols
Viscosity (Pa·s)
200
150
100
50
0
0.05

0.1

0.2

0.5

1

2

5

10

20

50

Shear rate (s-1)
Control

GARAMITE (more pseudoplastic)

RHEOBYK (more thixotropic)

G. 22

The efficiency of rheology additives depending on the PVC plastisol polarity, e.g. the polarity of plasticizers

Low polarity

Medium polarity

White spirit

Adipates

Benzoate/DNP (blends)

DIDP

Plasticizer 711
DINP

DINCH

High polarity

Polymeric plasticizer

Plasticizer 911

DOTP
RHEOBYK-410 series
RHEOBYK-7590
GARAMITE-1958
GARAMITE-7303

G. 23

17

Additives for PVC plastisol applications / Rheology additives

Benefits of BYK rheology additives

Improvedprint
definition

Front
Antisedimentationof pigments

Controlled
impregnation/leveling
Back

Effects of
BYK rheology
additives

Reduced flooding
and floatingof pigments

Improvedsag
resistance

G. 24

Left = control, right = with BYK additive

Additive recommendations
Product

Anti-settling

Sag control

Viscosity enhancement

Controlled
impregnation

Reduced flooding/ Chemistry
floating

Active substance

Solvent

RHEOBYK-410











Modified urea

52 %

NMP

RHEOBYK-D 410











Modified urea

52 %

DMSO

RHEOBYK-7410 ET











Modified urea

40 %Amide ether

RHEOBYK-7410 CA











Modified urea

47 %Cyclic amide

RHEOBYK-7590



Castor oil derivative

100 %

–

GARAMITE-1958











Organophilic phyllosilicates

100 %

–

GARAMITE-7303











Organophilic phyllosilicates

100 %

–

 Recommended



T. 03

18

Additives for PVC plastisol applications

Moisture absorbers
Why use moisture absorbers?

Benefits of BYK’s moisture absorber

The gelling of PVC plastisols requires high temperaturesof around 170-210 °C. High amounts of moisture in theplastisol can therefore lead to surface defects like blistering,caused by the boiling of entrapped water during the gelling
process. Moisture absorbers are thus used to remove waterfrom the system and enable defect-free coatings.

BYK’s moisture absorber is a finely-dispersed, low-emission
CaO paste that is pumpable and stable under normal
storage conditions. The high amount of surface area
provides optimal effectiveness (G. 25), so that moisture iseliminated even in large amounts in a short period of time.
Utilizing a special preparation technique in combination
with wetting and dispersing additives, the inorganic
moisture absorber CaO is activated and stabilized. Thus,
an extremely favorable dosage/effect is achieved.

Particle size analysis (laser diffraction)
Transmittance (%)
Large surface area due

100

to very fine particle size.
100 % < 15 µm
60 % < 2 µm

50

0
0.1

1

10

100

1000
Particle size (µm)

BYK additive

Various CaO pastes

CaO powder

G. 25

Benefits• Good storage stability (G. 26)• Pumpable• Dust-free• Incorporation possible at any time
during the PVC plastisol
production• Lower dosages needed compared
to standard CaO moistureabsorbers (G. 27)• Prevention of surface defects suchas blistering and craters during
the processing of plastics, e.g.
PVC, PU, and rubber (G. 28)• Enables coating without ­pre-drying if moisture is present in
the carrier or substrate• Absorbs moisture carried into thesystem by the polymer, fillers,
pigments, or reinforcement

19

Additives for PVC plastisol applications / Moisture absorbers

Efficiency of BYK additive compared toother moisture absorbers

Good storage stability due to high yield point
Viscosity (Pa · s)

Shear stress (Pa)
200

10.0

Dosage (%)
3 –5 %

5
7.5

150

5.0

100

2.5

50

4
2– 4 %

3

2
0.8 %

1
0

0
0

25

50

75

100

0

Shear rate (s-1)
Viscosity

G. 26

Shear stress

CaO fine, dry

Various CaO pastes

BYK additive

G. 27

Prevention of surface defects in a gelled PVC plastisol
with 0.5 % H2O
Without additive

With BYK additive

Additive recommendations
Product
BYK-2616

is recommended for use in all PVC plastisols with exception of chemically
foamed ­plastisols
T. 04

G. 28

20

Additives for PVC plastisol applications

Foam stabilizers for mechanical foams
Why use mechanical foams?

Key differences between silicone-based and­silicone-free foam stabilizers

Mechanical foams have a lower gelling temperaturecompared to chemically-blown PVC foams and provide goodsound insulation and rebound elasticity (thick coatings).
When used as an impregnation coat, a mechanically frothed
PVC plastisol can offer economic advantages, such as lesspaste at same impregnation and a reduced chance ofmoisture blistering.

One factor in determining whether to use a silicone orsilicone-free surfactant is the choice of plasticizers. The
silicone-free surfactant produces a foam with smaller cells
than those produced by a silicone stabilizer. In comparison
to silicone surfactants, a silicone-free surfactant needs aheat stabilizer to achieve the same foam whiteness (T. 05).

Differences between BYK-8020 and BYK-8070
EffectSilicone stabilizer Silicone-free stabilizer
BYK-8020
BYK-8070

Foam stability

Large, uniform
stable cells

Small, uniform stable cells

Foam color

Snow white

White, heat stabilizer
required

Water absorption

Hydrophobic

Hydrophilic
T. 05

Mechanism of mechanical foams
Air entrapment

Separation and s­ tabilizationof air by a foam stabilizer

Fusing at 150 °C–175 °C

With the use of special mixing equipment, air isentrapped in the PVC plastisol.

After air entrapment, the air is separated and stabilized
by a foam stabilizer

After achieving the desired foam density,
the plastisol is fused.

G. 29

21

Additives for PVC plastisol applications / Foam stabilizers for mechanical foams

Both silicone and silicone-free mechanical foam stabilizers
produce a uniform cell structure. During processing, thesynergism with rheology additives at low dosages ofaround 0.1–0.4 phr can enhance the froth stability of themechanical foam without affecting the foam’s froth density(G. 30).
Silicone-based foam stabilizers are hydrophobic in nature.
Thus, a mechanical foam made with these additives will
repel water. In contrast, a foam produced with a hydrophilic
foam stabilizer will absorb water (G. 31).

Additive recommendations
Product

Hydrophilicfoams

BYK-8020
BYK-8070

Hydrophobic
foams




Reduction of­density

Low emission

Low fogging













 Recommended

T. 06

Cross section of mechanical foams

Water absorption test

With silicone
foam stabilizer

Water droplet on PVC plastisol
with hydrophilic foam stabilizer

With silicone-freefoam stabilizer

G. 30

Water droplet on PVC plastisol
with hydrophobic foam stabilizer

G. 31

22

Additives for PVC plastisol applications

Processing additives
Why use processing additives?

BYK additive in comparison to commonly used products

Processing additives improve and influence the processing of
PVC plastisol applications.

Product

Silicones, waxes, stearates

BYK additive

During processing• Incompatible with PVC• Risk of migration, plate out• Good release properties• More compatible with PVC• No plate out• Excellent release properties

Foam cell structure
after processing• No influence on open cell structure, indentation • More open cells resulting in better indentation
recovery and increased air permeability
recovery, or foam breathability
T. 07

Comparison of mechanism

Waxes

Stearates

Silicones

BYK additive

PVC

Polar groups

PVC compatible groups

G. 32

23

Additives for PVC plastisol applications / Processing additives

The two main benefits of
BYK’s processing additives are:Benefits of processing additives
Improving release properties with BYK’s processing
additives

1.	Improving the releaseproperties• From metal parts(e.g. gelling drum)• From release paper• From flat screens and molds

By using BYK’s processing additives, improved releaseproperties of a re-gelled or gelled plastisol from a drum,
more turns or uses of release paper, and better flat screen
or mold release can be obtained even with low dosages,
e.g. 0.5 %.

2.	Influencing the cell structureof chemically blown foams• To improve the indentation
recovery• To increase air permeability

Additionally, the additives don’t show negative influenceson intercoat adhesion and are available silicone-, stearate-,
and wax-free.

Improving the release, e.g. from metal surfaces

Improved release from paper

Without additive

Force (N)With BYK additive

3.5
3
2.5
2
1.5
1
0.5
0
Control
G. 33

Without additive

1

With BYK additive

2

3

4

Dosage (phr)
G. 34

24

Additives for PVC plastisol applications / Processing additives

Influencing the cell structure of chemical blown foams

Additive recommendations

Processing additives can also be used to achieve an opencell structure resulting in improved indentation recovery andair permeability. Additionally, an increased water absorption
can be achieved. However, it should be noted that only
certain PVC types are suitable for open cell foams, and thisopen cell structure can only be achieved when formulation
ingredients and process parameters are balanced toeach other.

Product
BYK-P 4100

Gelling drum

Release paper Recommended

Cross section of a chemical foam formulation
Without additive

With BYK additive
Open cells on thesurface and highwater absorption

Closed cells on
the surface andno waterabsorption

G. 35

Conveyor belts Molds


Low emission


Low fogging

T. 08

25

Additives for PVC plastisol applications

Additives to increase electrical conductivity
Working mechanism of antistatic agents

Why use additives to increase conductivity?
In many application areas, such as ATEX (ATmosphere
EXplosible), electronic, or medical areas, it is important tocreate antistatic layers, e.g. on floorings, functional textiles
or conveyor belts, to avoid explosions or static charging.
This can be achieved by using additives that increaseelectrical conductivity or decrease resistivity to values
in the antistatic range.

Standard antistatic agentsO
H

BYK additive
O

H

H

O
H

H

O
H H

O
H H

O
H H

O
H H

O
H H

H

Benefits of BYK’s additive to increase conductivity
BYK’s additive to increase conductivity is a non-ionicantistatic agent with a well-balanced and optimized
amphiphilic structure that leads to the formation of ahygroscopic layer of the additive on the PVC surface. This
results in the arrangement of water molecules into a thincontinuous film of water and the creation of a conductive
path to dissipate electrostatic charges.

Volume resistivity in a calendered flooring formulation after 28 days

Additive recommendations

Volume resistivity (Ω)

Product
BYK-5128

FilledSurfaceresistivity

Volumeresistivity





G. 36

1.00E+12
1.00E+11

Insulation

1.00E+10
1.00E+09
1.00E+08

 Recommended

T. 09

1.00E+07

Antistatic

1.00E+06
1.00E+05
1.00E+04
Test formulation:
100 phr S-PVC
40 phr Plasticizer
2 phr Stabilizer
2 phr ESO
50 phr CaCO3

1.00E+03

Conductivity

1.00E+02
1.00E+01
1.00E+00

Control+0.6 phr BYK-5128+1.4 phr BYK-5128+2.8 phr BYK-5128
G. 37

26

Additives for PVC plastisol applications

Additives to increase the surface energy after gelling
Why use additives to increase the surface energy?

Test methods

The wetting of a surface with a liquid depends on thesurface tension of the liquid, but also of the substrate to becoated. Generally, the surface tension of the coating should
be lower than or equal to the surface energy of thesubstrate in order to achieve a good wetting. Poor wetting,i.e. a crawling or beading of the coating, will occur if thesurface tension of the coating is higher than the surface
energy of the substrate. Substrates with a generally lower
surface energy or contaminated surfaces (oil residue, releaseagent) are therefore difficult to wet.

Free surface energy
The free surface energy of solids can be determined bycontact angle measurements where defined liquids areapplied on solid surfaces. The free surface energy is thencalculated using different models (e.g. WORK, Wu).

Generally, a higher polarity goes along with a higher surface
tension. Especially on low-polar PVC substrates, coating or
printing with highly polar aqueous ink systems can therefore
be challenging, as the high water content leads to a higher
surface tension of the coating. Therefore, additives that
increase the surface energy of PVC plastisols after gelling areneeded to achieve a substrate that can be coated properly.

Static surface tension
The static surface tension can be measured using the Du
Noüy ring method. A platinum-iridium ring is drawn out of
the liquid while, at the same time, the maximum force
caused by the tension of the liquid lamella during the
movement of the ring is measured.
Du Noüy
ring method

Contact angle measurement

0°

< 90°

90°

> 90°

180°

G. 38

27

Additives for PVC plastisol applications / Additives to increase the surface energy after gelling

Benefits of additives to increase the surface energy
after gelling

Additive recommendations
Product

Using BYK’s additive increases the surface energy and thepolarity of PVC plastisols after gelling without influencing
the surface tension of the liquid plastisol, leading to
improved wetting of the gelled plastisol by subsequent
layers, such as printing inks, as well as an enhanced
adhesion and very good leveling of the subsequent layers. It
also improves the leveling of the system in which it is used.

Transparent

BYK-3560

FoamedFilled Recommended

T. 10

Wetting behavior dependingon the surface energy

Improved wetting of low-polar
PVC substrates
Without additive

Liquid coating

Liquid coatingWith BYK additive

Liquid coating
Interaction

PVC substrate A

PVC substrate A

Disperse parts

Polar parts

PVC substrate B

PVC substrate B

G. 39

G. 40

08/2022
PVC-TI 8
BYK-Chemie GmbH
Abelstraße 4546483 Wesel
GermanyTel +49 281 670-0
Fax +49 281 65735

ADD-MAX®, ADD-VANCE®, ANTI-TERRA®, AQUACER®, AQUAMAT®, AQUATIX®, BENTOLITE®, BYK®, BYK-AQUAGEL®, BYK®-DYNWET®, BYK-MAX®,
BYK®-SILCLEAN®, BYKANOL®, BYKCARE®, BYKETOL®, BYKJET®, BYKO2BLOCK®, BYKONITE®, BYKOPLAST®, BYKUMEN®, CARBOBYK®, CERACOL®,CERAFAK®, CERAFLOUR®, CERAMAT®, CERATIX®, CLAYTONE®, CLOISITE®, DISPERBYK®, DISPERPLAST®, FULACOLOR®, FULCAT®, GARAMITE®,GELWHITE®, HORDAMER®, LACTIMON®, LAPONITE®, MINERPOL®, NANOBYK®, OPTIBENT®, OPTIFLO®, OPTIGEL®, POLYAD®, PRIEX®, PURABYK®,
PURE THIX®, RECYCLOBLEND®, RECYCLOBYK®, RECYCLOSSORB®, RECYCLOSTAB®, RHEOBYK®, RHEOCIN®, RHEOTIX®, SCONA®, SILBYK®, TIXOGEL®
and VISCOBYK® are registered trademarks of the BYK group.

info@byk.com
www.byk.com

The information herein is based on our present knowledge and experience. The information merely describes the properties of our products but noguarantee of properties in the legal sense shall be implied. We recommend testing our products as to their suitability for your envisaged purpose prior touse. No warranties of any kind, either express or implied, including warranties of merchantability or fitness for a particular purpose, are made regarding
any products mentioned herein and data or information set forth, or that such products, data or information may be used without infringing intellectual
property rights of third parties. We reserve the right to make any changes according to technological progress or further developments.
This issue replaces all previous versions.