1/6

Additives for Solvent-Free Epoxy Floor Coatings

1. Introduction
Many floors of offices, factories and warehouses are coated with floor coatings. Features of afloor coating are good physical properties and a low price. 2K Polyurethane coatings and Epoxy
coatings are used for these floors. Especially, Epoxy floor coatings are widely used because of
their excellent durability, abrasion resistance, load bearing, impact resistance, chemicalresistance, oil resistance and so on.
Recently, due to environmental issues and odor problems, solvent-free epoxy floor coatings aregetting more and more popular. Solvent-free types are better for our health and have lessunpleasant odors. Furthermore, using a solvent-free type, we can get a thicker coating.
On the other hand, there are a lot of issues such as foaming, poor workability and poor
self-leveling since containing no solvents results in an increased viscosity and shorter pot life.
Therefore, various additives are used to solve these problems.
In this document, we would like to introduce our additives which are used for solvent-free epoxy
floor coatings.

2. Pigment-Wetting and Dispersing Agent
2-1. Typical properties of DISPARLON DA-325
Table-1
Appearance

Light yellow to amber, viscous liquid

Active component

Amine salt of polyether phosphate

Non-volatile matter

95% by wt.

Acid value

14

Amine value

20

The pigment-wetting and dispersing agent DISPARLON DA-325 is a solvent-free polymer typedispersant. DA-325 is composed of a phosphate group for absorbing onto pigments and apolyether part for compatibility. The polyether part extends in resins and creates a sterichinderance repulsion effect. Therefore DA-325 is effective for the wetting and dispersing ofpigments.

Copyright 2013. Kusumoto Chemicals, Ltd. All right Reserved.

2/62-2. Wetting and dispersing effects of DA-325
This is the dispersing test result of DA-325 in a solvent-free epoxy floor coating which contains
talc as the body pigment. Without dispersant, pigment particles flocculate and cause anincreased viscosity. The dispersant wets the pigments, prevents pigment flocculation andprovides decreased viscosity. Figure-1 shows the flow curves of the floor coatings containing
DA-325. DA-325 decreased the viscosity, and provided "Newtonian flow" at a dosage level of
2% or more. As shown in Photo-1, DA-325 improved the fluidity of the paint. Thus DA-325 canmake pigment dispersion easy at the production stage, and improve the self-leveling properties
during the paint application.
10000

Table-2 Formulation

Blank
DA-325 1%
DA-325 2%DA-325 3%PartsjER 815 ( Mitsubishi Chem.)

75

Talc #1 ( Takehara Kagaku)

75

DA-325X

viscosity (Pa.s)

1000

Component

100.0

10.00

1.000
1.000E-3 0.01000

0.1000
1.000
10.00
shear rate (1/s)

100.01000

Figure-1 Flow curve change by DA-325

BLANKDA-325 2.0 %BLANK

Photo-1 Fluidity of the paint improved by DA-325

Copyright 2013. Kusumoto Chemicals, Ltd. All right Reserved.

DA-325 2.0 %3/6

3. Defoamer
3-1. Typical properties of DISPARLON defoamers
Table-3
SPX-20

SPX-21

Appearance

SPX-44

Colorless to light yellow liquid

Active component

Vinyl polymer

Acrylic polymer

Silicone

Active %20%20%

1%Solvent naphtha

Solvent naphtha

Butyl acetate

XyleneSolvent

Ethyl acetate

DISPARLON SPX-20 and SPX-21 are Vinyl / Acrylic polymer type defoamers. SPX-20 andSPX-21 are suitable for high polar resin systems like Epoxy resins and they have levelingproperties as well as defoaming properties.
DISPARLON SPX-44 is a silicone type defoamer. SPX-44 has a strong defoaming effect, can beused in a wide range of paints and has no influence on the film clarity.

3-2. Defoaming effect of DISPARLON defoamersThis is the defoaming test result of DISPARLON defoamers in a solvent-free epoxy floor coating.
Compared to the Blank, SPX-20 showed an excellent defoaming effect. (Photo-2)
Table-4 Formulation
Component

PartsEP-4510 ( Adeka Corp.)

50.0

CaCO3

35.0

Talc

5.0

TiO2

7.0

Phthalocyanine green

1.5

Iron oxide yellow

1.5

SPX-201.0

EH-428W ( Adeka Corp. )

20.0

BLANK

LAP-10 1%
SPX-20

Photo-2 Defoaming effect of SPX-20

Next is the defoaming and transparency test result in an Epoxy clear topcoat. SPX-44 wassuperior to Additive A (competitor) regarding defoaming property and clarity. (Photo-3)
SPX-44 can be used in an Epoxy clear topcoat formulation.

Copyright 2013. Kusumoto Chemicals, Ltd. All right Reserved.

4/6Table-5 Formulation

SPX-44Component

Parts

jER 828 (Mitsubishi Chemical)

90

SY-40M (Sakamoto Yakuhin)

10

Defoaming agent

0.5

DOCURE KH-816 (Kukdo)

58.0

Defoaming

Clarity

Photo-3 Defoaming and Clarity of SPX-44

4. Combination of Dispersant and Defoamer
Combining a dispersant and a defoamer has a synergistic effect.
Formulation-1
Table-6Component

Part APart B

Parts

Function

Supplier

YD114E

100

Epoxy resin

Kukdo

CR-93

5TiO2

Ishihara industrial

Talc40FillerTakehara chemical

DA-325

3.5

Dispersant

Kusumoto Chemicals

SPX-201.5Defoamer

Kusumoto Chemicals

KH816

55

Hardener

Kukdo

FUSELEX 100~200M

80

SilicaTatsumori

FUSELEX 60~100M

100

SilicaTatsumoriPart C

Figure-2 shows flow curves of Part A. DA-325 decreased the viscosity and gave flow curves close
to a Newtonian flow. SPX-20 didn’t affect the paint flow property.
As shown in Photo-4, DA-325 reduced viscosity and made air-releasing easier, but didn’t havedefoaming property so the film appearance of DA-325 was similar to Blank. SPX-20 defoamed
the film well, but was not perfect. However, the combination of DA-325 and SPX-20 provided anexcellent film. This is because DA-325 which reduces viscosity and makes air-releasing easierhelps the defoaming effect of SPX-20. Furthermore, lower viscosity and the leveling effect ofSPX-20 enhanced the self-leveling properties of the paint and improved the film appearance.

Copyright 2013. Kusumoto Chemicals, Ltd. All right Reserved.

5/6
3500

BLANK
DA-325
SPX-20Viscosity [mPa･s]

3000

2500

Blank

DA-325

SPX-20
LAP-10DA-325/ LAP-10DA-325/ SPX-20

2000

1500

1101001000

shear rate [s-1]Figure-2 Flow curve

Photo-4 Film appearance( Part A )Formulation-2
Table-7
Component

Part APart B

PartsFunction

Supplier

EPOTEC YD128

85

Epoxy resin

ADTIYA BIRLA

SY-40M

15

Glycidyl ether

Sakamoto Yakuhin Kogyo

CR-93

5TiO2

Ishihara industrial

Talc

40

FillerTakehara chemical

DispersantX

DefoamerY

Versamine C60N

60

Cycloaliphatic amine

Cognis

Blank

Photo-5

DA-325 1sop%

Dispersant A 1sop%

SPX-21 0.1%

Defoamer A 0.1%

Film appearance ( sop% : solid % on total pigment )In this formulation, the combination of DA-325 and SPX-21 provided an excellent film, and wassuperior to the combination of competitive Dispersant A and competitive Defoamer A.

Copyright 2013. Kusumoto Chemicals, Ltd. All right Reserved.

6/6
Figure-3 shows the mechanism of the synergetic effect of a dispersant and a defoamer.
Foam in a fluid floats to the surface and then breaks up caused by the defoamer particles.
However, if the viscosity of a coating solution is high, the foam floating rate is slow, therefore,
the film is crosslinked before foam reaches the surface. Thus the defoaming of a high viscosity
fluid is very difficult.
A dispersant reduces the viscosity of a coating and provides a Newtonian flow, therefore, helps
the air-release and the defoamer can break foam bubbles on the surface efficiently with the helpof the dispersant. So the combined use of a dispersant and a defoamer has the synergetic effect.
Furthermore, lower viscosity provided by a dispersant is good for the self-leveling of a floor
coating. A leveling agent or a defoamer which has leveling effect (e.g. SPX-20 / SPX-21) also
helps the self-leveling.
The combination of a dispersant and a defoamer provides excellent film surfaces.

DefoamerDefoamer

Foam* Efficient defoaming

FilmDispersant

Dispersant & Defoamer* Reduce viscosity* Reduce viscosity* Help air-release* Improve leveling

Excellent FilmAppearance!!

Figure-3 Mechanism of the synergetic effect of a dispersant and a defoamer

As mentioned in this document, the combination of different kind of additives is very effective to
get an excellent appearance of Epoxy floor coatings.

Copyright 2013. Kusumoto Chemicals, Ltd. All right Reserved.