Coatings Technology Handbook Episode 2 Part 8 potx

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Coatings Technology Handbook, Third Edition

72.4.1.2 Acetal

The most effective mold release agents in acetal are fatty amides in general and fatty bisamides amides
in particular. Ethylene bisoleamide shows 25.1% reduction of mold release force at 5000 ppm but causes
a visible darkening of the resin during processing. Ethylene bisstearamide, a saturated amide, is nearly
as good, showing 23.3% reduction at a level of 5000 ppm; it does not cause any color problems. Other
secondary amides, such as stearyl stearamide and stearyl erucamide, give mold release improvement
nearly as good as the bisamides (see Table 72.3). Primary amides such as erucamide, oleamide, and
stearamide also show good mold release enhancement in acetal.
None of the nonamide materials examined has the mold release effectiveness of the amides. The best
ester mold release agent is cetyl palmitate, which exhibited a 16.5% reduction in mold release force at a
5000 ppm treatment level.
The optimum amount of ethylene bisstearamide is 5000 ppm. When used above that level, there is
little increase in effectiveness; below that amount, the maximum effectiveness is not reached.
The use of fatty amides as mold release agents has negligible effect on mechanical properties (see Table 72.4).

72.4.1.3 Polybutylene Terephthalate

Fatty bisamides are the best mold release agents in polybutylene terephthalate (PBT). Both saturated and
unsaturated bisamides show about 10% reduction of ejection force when used at a level of 5000 ppm.
The bisoleamide, however, causes some darkening of the resin during processing (see Table 72.5).

TA BLE 72.3

Effectiveness of Mold Release Agents in Acetal

Release Agent Level (ppm) Reduction of Ejection Force (%)

N

,

N

′

-Ethylene bisstearamide 7500 26.0

N

,

N

′

-Ethylene bisoleamide

a

5000 25.1

N

,

N

′

-Ethylene bisstearamide 5000 23.3
Stearyl stearamide 5000 21.1
Stearamide 5000 20.4
Erucamide 5000 21.8

N

,

N

′

-Ethylene bisstearamide 2500 15.2

N

,

N

′

-Ethylene bisstearamide 1000 5.3
Fluorocarbon spray-on — 22.1

a

Causes resin to darken during processing.

TA BLE 72.4

Mechanical Properties of Acetal with

N,N

′

-

Ethylene Bisstearamide Present

Property

N,N

′

-Ethylene Bisstearamide (ppm)
0 2500 5000

Te nsile strength at yield, psi 9965 9883 9818
Elongation at break, % 36 39 41

Izod impact, ft-lb/in. 1.30 1.32 1.35

TA BLE 72.5

Effectiveness of Mold Release Agents in PBT

Release Agent Level (ppm) Reduction of Ejection Force (%)

N,N

′

-Ethylene bisoleamide 5000 9.8

N,N

′

-Ethylene bisstearamide 5000 9.4
Stearamide 5000 6.7
Erucamide 5000 6.2

N,N

′

-Ethylene bisstearamide 2500 7.7

N,N

′

-Ethylene bisstearamide 1000 2.7
Fluorocarbon spray-on — 8.8

a

May cause resin to darken during processing.

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Nonmetallic Fatty Chemicals as Internal Mold Release Agents in Polymers

72

-5

Other mold release agents, such as fatty esters, amines, and acids, are not as effective as the amides.
do not show any more effectiveness than 5000 ppm.
The use of fatty amides as mold release agents in PBT has negligible effect on mechanical properties
when tested at room temperature (see Table 72.6).

72.4.2 Polyolefins

72.4.2.1 Polypropylene

Glyceryl monostearate (GMS) has been found to be the best mold release agent in polypropylene. At a
level of 2500 ppm, GMS shows about 24% reduction of mold release force. The reduction in mold release
force is the same regardless of whether the GMS has 45, 60, or 90%

α

-monostearate (see Table 72.7).
The remainder of the monostearate is

β

-monostearate, distearate, and small amounts of tristearate. When
the amount of

α

-monostearate is less than 45%, there is a decrease in mold release enhancement.
Other glyceryl monoesters have also been tested, and only glyceryl monolaurate is as good a mold
release agent as GMS. In addition to glycerol esters, ethylene glycol distearate and monostearate, cetyl
palmitate, and methyl stearate have been examined. None is as good as GMS.
The results of these experiments indicate that the greater the amount of free hydroxyl in the ester, the
more effective the mold release agent, up to a certain amount. Perhaps the hydroxyl groups make the
additive less soluble in the resin, thus making it exude more to the surface. After a certain amount of
hydroxyl has been reached, the migration to the surface reaches a maximum and further increases do
not further enhance migration.
reduction of mold release force when used at a level of 5000 ppm. This amount of reduction is comparable
to GMS, although the GMS is used at a lower level.
The use of glyceryl monostearate or erucamide as mold release agent in polypropylene has a negligible

72.4.2.2 High-Density Polyethylene

The best mold release agent in high-density polyethylene (HDPE) is erucamide. At a level of 2500 ppm
it shows a mold release force reduction of about 22%. Other primary amides are also fairly effective as

TA BLE 72.6

Mechanical Properties of PBT with

N,N

′

-Ethylene

Bisstearamide

Property

N,N

′

-Ethylene Bisstearamide (ppm)
0 2500 5000

Te nsile strength at yield, psi 9640 8664 8840
Elongation at break, % 299 249 227
Izod impact, ft-lb/in. 1.00 1.05 1.030

TA BLE 72.7

Effectiveness of Mold Release Agents in Polypropylene

Release Agent Level (ppm) Reduction of Ejection Force (%)

Glyceryl monostearate
45%

α

-monoester 2500 23.9
60%

α

-monoester 2500 23.8
90%

α

-monoester 2500 22.4
Glyceryl distearate
12%

α

-monoester 2500 15.9
Erucamide 5000 25.8
Fluorocarbon spray-on — 23.1

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The optimum amount of ethylene bisstearamide in PBT is between 2500 and 5000 ppm (see Table

72.5). Amounts less than 2500 ppm show a steep decline in effectiveness, while amounts above 5000 ppm
Fatty amides also show some utility as mold release agents in polypropylene. Erucamide shows 25.8%
effect on the mechanical properties (see Table 72.8).

Nonmetallic Fatty Chemicals as Internal Mold Release Agents in Polymers

72

-7

72.5 Conclusions

It has been shown that it is possible to measure qualitatively the effectiveness of internal mold release
agents in injection molding. Numerous fatty chemicals were tested in polyolefins and engineering resins.
The chemical type that is the most effective mold release agent in a particular resin varies widely with
resin type. The required mold release pressure can be reduced for each of these resins without a significant
change in the mechanical properties of the resin. One or more preferred mold release agent has been
suggested for each resin.

Acknowledgment

Some of the information in this chapter is covered under an existing patent and a pending patent.

TA BLE 72.11

Effectiveness of Mold Release Agents in LLDPE

Release Agent Level (ppm) Reduction of Ejection Force (%)

Erucamide 5000 49.8

Erucamide 2500 43.1
Erucamide 1000 30.2
Ethoxylated tallow amine 2000 30.9
Ethoxylated oleyl amine 2000 29.6
Glyceryl monostearate 2000 26.0
Fluorocarbon — 11.1

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73

Organic Peroxides

73.1 Introduction

73-

1
73.2 Types and Properties

73-

1

73.3 Application in Coatings

73-

4
73.4 Safety Factors and Producers

73-

5
73.5 Future Trends

73-

5
References

73-

5

73.1 Introduction

Organic peroxides are derivatives of hydrogen peroxide, HOOH, wherein one or both hydrogens are
replaced by an organic group (i.e., ROOH or ROOR).

1–5

They are thermally sensitive and decompose by
homolytic cleavage of the labile oxygen–oxygen bond to produce two free radicals:
(73.1)

The temperature activity of organic peroxides varies from below room temperature to above 100

°

C,
depending on the nature of the R groups. In addition to thermal decomposition, certain organic peroxides
can be decomposed by activators or promoters at temperatures well below the normal decomposition
temperature.
A major application of these compounds is as free radical initiators in the polymerization of vinyl and
diene monomers in the plastics and coatings industries. They are also used as cross-linking and modifying
agents for polyolefins, as vulcanizing agents for elastomers, and as curing agents for polyester resins.

73.2 Types and Properties

Peroxide manufacturers now offer over 50 different organic peroxides in more than 100 formulations
including dilutions in solvents, pastes, and filler-extended grades. In most cases, these formulations are
designed for specific applications and to allow shipping and handing with a reasonable degree of safety.
peroxides are commonly reported in terms of half-life (

t

1/2

) temperature, that is, the time at which 50%
of the peroxide has decomposed at a specified temperature. Table 73.1 lists the 10-hour

t

1/2

temperature
ranges for the major organic peroxide types. Peroxides of certain types, such as hydroperoxides and
ketone peroxides, are primarily used in combination with promoters and are employed at temperatures
much lower then their measured 10-hour

t

1/2

temperature.
ROOR RO OR
′
→⋅+⋅
′
∆

Peter A. Callais

Pennwalt Corporation

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Peroxide Selection • Radical Types
The major classes of commercial organic peroxides are shown in Table 73.1. Decomposition rates of

73

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Coatings Technology Handbook, Third Edition

15.

t-Amyl Peroxides

(product bulletin), Lucidol Division, Pennwalt Corporation, Buffalo, NY, 1985.
16. M. Takahashi,

Polym. Plast. Technol. Eng., 15

, 1 (1980).
17. L. W. Hill and Z. W. Wicks, Jr.,

Prog. Org. Coat., 10

, 55 (1982).
18. R. H. Kuhn, N. Roman, and J. D. Whitman,

Mod. Paint Coat., 71

(5), 50 (1981).
19. R. F. Storey, in

Surface Coatings

, A. L. Wilson, J. W. Nicholson, and H. J. Prosser, Eds. London:
Elsevier Applied Science, 1987, p. 69.
20. C. J. Bouboulis, U.S. Patent 4,739,006 (1988).
21. D. Rhum and P. F. Aluotto, U.S. Patent 4,075,242 (1978).
22. Y. Eguchi and A. Yamada, U.S. Patent 4,687,882 (1987).

23. W. R. Berghoff, U.S. Patent 4,716,200 (1987).
24. R. A. Gray,

J. Technol., 57

(728), 83 (1985).
25. R. Buter,

J. Technol., 59

(749), 37 (1987).
26. D. Rhum and P. F. Aluotto,

J. Technol., 55

(703), 75 (1983).
27. V. R. Kamath and J. D. Sargent, Jr.,

J. Coat. Technol., 59

(746), 51 (1987).
28. V. R. Kamath, U.S. Patent pending.
29. F. M. Merrett,

Trans. Faraday Soc., 50

, 759 (1954).
30. D. H. Solomon,

J. Oil Colour. Chem. Assoc., 45

, 88 (1962).
31. J. Sanchez, U.S. Patent 4,525,308 (1985).
32. A. J. D’Angelo and O. L. Mageli, U.S. Patents 4,304,882 (1981), 3,952,041 (1976), 3,991,109 (1976),
3,706,818 (1972), and 3,839,390 (1974).
33. A. J. D’Angelo, U.S. Patent 3,671,651 (1972).
34. R. A. Bafford, U.S. Patent 3,800,007 (1974).
35. R. A. Bafford, E. R. Kamens, and O. L. Mageli, U.S. Patent 3,763,112 (1973).
36. O. L. Mageli, R. E. Light, Jr., and R. B. Gallagher, U.S. Patent 3,536,676 (1970).
37. H. Ohmura and M. Nakayama, U.S. Patent 4,659,769 (1987).
38. C. S. Sheppard and R. E. MacLeay, U.S. Patents 4,042,773 (1977) and 4,045,427 (1977).
39. T. N. Myers, European Patent Appl., 223,476 (1987).
40. P. A. Callais, V. R. Kamath, and J. D. Sargent,

Proc. Water-Borne Higher Solids Coatings Symp., 15

,
104 (1988).

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74

Surfactants for
Waterborne Coatings

Applications

74.1 Introduction

74-

1
74.2 Chemistry

74-

1
74.3 Theory

74-

2
74.4 Foam Control

74-

3
74.5 Wetting

74-

4
74.6 Conclusion

74-

5

74.1 Introduction

As governmental regulations become increasingly restrictive, waterborne coatings appear to be the logical
choice for many paint manufacturers. However, the technological switch from solvent to waterborne
systems requires an understanding of the challenges that lay ahead with respect to wetting, foam control,
and coverage over difficult-to-wet substrates.
This chapter will help explain the important contribution of wetting agents and defoamers to the
emerging technology of waterborne coatings. Topics will include the chemistry of several surfactants
along with a thorough analysis and understanding of surface tension. Surface tension reduction and
mechanisms relating to foam stabilization will be reviewed.

74.2 Chemistry

All surfactants fall into two classifications, nonionic and ionic. Within the ionic category, surfactants can
be further subdivided into anionic, cationic, or amphoteric types. For coatings, most surfactants utilized
are either nonionic or anionic. For wetting agents, the products we will compare include alkylphenol
ethoxylates, sodium dioctyl sulfosuccinates, sodium laurel sulfates, block copolymers of ethylene and
propylene oxides, alkyl benzene sulfonates, and, finally, a specialty class called acetylenic glycols. We start
with this.
Acetylenic glycols are a chemically unique group of nonionic surface active agents that have been
especially designed to provide multifunctional benefits to a wide array of waterborne coating products.
Two key benefits include an unusual combination of wetting and foam control properties.
Characterized as an acetylenic

diol,

we have a 10-carbon backbone molecule with a triple bond, two
adjacent hydroxyl groups, and four symmetrical methyl groups. Based on acetylene chemistry, this
product is unlike any other surfactant molecule. The combination of the triple bond and the two hydroxyl
groups creates a domain of high electron density, making this portion of the molecule polar and thus

Samuel P. Morell

S. P. Morell and Company

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75

Surfactants,
Dispersants, and
Defoamers for the
Coatings, Inks, and

Adhesives Industries

75.1 Introduction

75-

1

75.2 Wetting and Dispersing Process

75-

2

75.3 Silicones and Surface Flow Control Agents

75-

6

75.4 Defoaming Additives

75-

9

75.5 Conclusion

75-

12
References

75-

12

75.1 Introduction

Over the history of coatings, inks, and adhesives, many evolutionary changes have occurred; not only
have the ingredients used to make the formulations been changed, but also the physical characteristics
of the formulations along with their application, cure, and performance parameters have changed.
Of course, each trend poses challenges to both raw material suppliers and formulators alike. Because
additives are used to enable and enhance system performance, the evolution of resins, pigments, solvents,
and application technologies pose special challenges for additive suppliers.
Resin and solvent combinations used in the good old days were typically quite low in surface tensions
in comparison to modern formulations. Today’s more environmentally friendly formulations with little
or no solvents, or in the case of aqueous formulations, with little or no cosolvents, require increased use
of interfacially active materials in order to provide adequate substrate wetting, surface flow, and the
prevention of foaming and air entrapment.

John W Du

BYK-Chemie USA

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The Wetting and Dispersing Process • Waterborne Systems •
Background • Chemical Structure of “Silicones” • Surface
Solvent-Based Systems • Classification • Summary
Phenomena and the Elimination of Defects • Summary
Selection Criteria and Test Methods • Summary
The Nature of Foam • Defoamers versus Air Release Agents •
for Aqueous Systems • Defoamers for Solvent-Based Systems •
The Mechanisms of Defoaming and Air Release • Defoamers

Surfactants, Dispersants, and Defoamers

75

-5

Controlled flocculation

means that pigments and extenders are stabilized as defined and selectively
interactive units or groups of multiple particles. Rheology will be modified to exhibit thixotropic behavior,
resulting in improved resistance to settling and sagging. A coating system stabilized in this manner will
also be more resistant to flooding or floating.

75.2.4.1 Deflocculating Additives

Depending on the actual ingredients of a given formulation, wetting and dispersing behavior can be
tailored on a case-by-case basis. One of the more important parameters is the pigment’s surface polarity.
Highly polar pigment surfaces generally require the use of lower molecular weight polymeric additives,
whereas nonpolar pigment surfaces require higher molecular weight species.
Deflocculating additives possess at least one pigment affinic group. Higher molecular weight defloc-
culating additives generally have multiple pigment affinic groups, arranged in such a manner that all of
the groups are available for adsorption onto a pigment particle’s surface.
Following additive adsorption, the binder-compatible molecular chains of the additive can then extend
into the liquid binder. Enveloping the pigment particles with additive and preventing direct pigment–pig-
ment contact, these binder-compatible chains of the deflocculating additive, in conjunction with the
binder, are responsible for steric hindrance. In the case of incompatibility between the molecular chins
of the deflocculating additive and the binder, the molecular chains cannot extend into the liquid phase
but rather coil, thus failing to provide sufficient spacing and adequate steric hindrance.
Deflocculation generally leads to more efficient pigment utilization, which (especially in the case of
some rather expensive organic pigments) is not, economically, unimportant. The degree of deflocculation
or flocculation greatly impacts the developed shade or tint of a pigment. If, for example, a system tends
to settle during storage, then color shifts may occur. In situations where this is especially critical (such

as in the base components of a mixing system), the only acceptable method for producing coatings with
a constant and defined color and shade is the complete deflocculation method as described below.
A new group of additives has been recently developed — high molecular weight polymeric wetting
and dispersing additives. Such additives provide complete deflocculation and, consequently, differentiate
themselves from their conventional low molecular weight analogs through molecular weights sufficiently
high to allow these additives to have resin-like characteristics. Additionally, these new additives contain
a considerably higher number of pigment-affinic groups per molecule. Because of these structural
features, such additives can form durable adsorbed layers onto many organic pigments. Stabilization
arises, in part, from steric hindrance (exactly as with the conventional products) in which well-solvated
polymer chains are utilized; however, optimal stabilization is possible only when such polymer chains
are properly uncoiled (fully extended) and highly compatible with the surrounding resin solution. If this
compatibility is compromised (by resin or solvent composition changes), the polymer chains collapse.
Consequently, particulate spacing, steric hindrance, and dispersion stabilization are lost.

75.2.4.2 Controlled Flocculation Additives

If the pigment affinic groups are not confined to a small region of the additive molecule but rather are
distributed in a specific fashion over the entire molecule, then such an additive will be capable of simul-
taneously contacting two or more pigment particles in a bridge-like fashion, and controlled flocculation
results. At this point, it is important to clarify the difference between the above condition of controlled
flocculation and the normal flocculated state. Without additives, the pigment particles make direct contact
with one another in uncontrolled flocculation. In contrast, no direct pigment-to-pigment contact occurs
in controlled flocculation; additive molecules are always present between the pigment particles.
Ordinary flocculation without additive (resulting in direct pigment-to-pigment contact) is not control-
lable. Such a flocculated coating will exhibit batch-to-batch variation in properties such as color and shade
or perhaps even shelf life; unpredictable nonrecoverable settling and sedimentation occurs during storage.
Controlled flocculation provides a means for particulates to associate with each other without actually
coming in contact. This association allows large domains of controlled flocculates to move as a single
unit while maintaining the individual particle-to-particle spacing that is required for stability. This type

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Coatings Technology Handbook, Third Edition

required to draw a defined mass across the coating’s surface. Silicone additives generally reduce friction,
i.e., they improve slip depending on their chemical structures and concentrations. Generally, the more
dimethyl groups in the structure, the more slip is enhanced. Better slip may be the desired property, but
oftentimes, slip is desirable for other reasons, because coatings with improved slip will simultaneously
display better mar and scratch resistance, along with improved blocking resistance. An added benefit is
nearly always improved resistance to soiling.

75.3.3.4 Mobility of Siloxanes/Intercoat Adhesion

Next, comparing reactive versus nonreactive modifications to the polydimethylsiloxane, cross-linking the
siloxane via functional modifications, with resin binders, will inhibit recoat. This is shown at the bottom
of Figure 75.4. At temperatures greater than 150ºC/300ºF, nonreactive polyether-modified siloxanes will
decompose, forming reactive groups that function to preventing migration. Nonreactive silicones do not
remain permanently at the surface of the first layer of cured paint; upon recoat, they migrate into the
second coat and orient at its air interface. This migration of silicone from the first coat is what permits
the second layer of paint to wet and adhere to the first coat. (This is shown in the upper two-thirds of
Figure 75.4.) Through manipulation of the modifications to the basic polydimethylsiloxane molecule,
intercoat adhesion can be controlled. Specially designed, thermally stable polysiloxanes have also been
developed for recoatability in high-temperature (up to 220ºC/430ºF) baking systems.

75.3.3.5 Surface Tension Reduction for Substrate Wetting

Due to their surface activity, conventional silicones typically concentrate at the liquid/air interface.
Characteristic of silicones is their ability to reduce surface tension.
In order for a formulation to wet a substrate, the liquid components of the formulation must have a
lower composite surface tension than that of the substrate. In solvent-based systems, and some waterborne
systems, this requirement can be met by the use of silicone additives of the structures previously discussed.
In waterborne systems, substrate wetting can be difficult, due to the high surface tension of water.
Conventional silicone additives (as described above) often cannot correct wetting defects, as they do not
sufficiently reduce the surface tension of the coating. The correct product to use for these situations are
often “silicone surfactants.” Such products are able to provide very low surface tension values in waterborne
coatings, thereby avoiding wetting problems. They can often be used to replace fluoro surfactants. However,
fluoro surfactants, in addition to reducing surface tension (and being more expensive), also exhibit a
pronounced tendency to stabilize foam. It is important to note that silicone surfactants do not stabilize foam.

75.3.3.6 Controlled Incompatibility

The compatibility of any particular silicone with a binder solution depends on its chemical structures
— the presence of modifying side chains and molecular weight. Highly incompatible silicones tend to
cause surface defects (such as craters) and may actually be used to generate hammer-tone finish coatings.

FIGURE 75.4

Mobility of silicones.

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Surfactants, Dispersants, and Defoamers

75

-13

10. W. Heilin and S. Stuck, “Polysiloxane zur Erhöhung der Kratzfestigkeit von Beschictungsober-
flächen,”

Farbe und Lack

,

101

, 376 (1995).
11. L. H. Brown, “Silicone additives,” in

Handbook of Coatings Additives

. L. J. Calbo, Ed. New York:
Marcel Dekker, 1987.
12. S. Paul, “Methods used to reduce foaming,” in

Surface Coatings

, 2nd ed. Chichester: John Wiley,
1985, pp. 622–625.
13. J. W. Simmons, R. M. Thorton, and R. J. Wachala, “Defoamers and antifoams,” in

Handbook of
Coatings Additives

. L. J. Calbo, Ed. New York: Marcel Dekker, 1987.
14. M. S. Gebhard and L. E. Scriven, “Formulation and dissipation of air bubbles in spray-applied
coatings,” in

Proceedings of the Twenty-first Waterborne, Higher Solids, and Powder Coatings Sym-
posium

. R. F. Thames, Ed. University of Southern Mississippi, 1994.
15. H. Van Megan, “Defoamers in organic solvent and waterborne paint systems,”

Färg Och Lack
Scandinavia

, 142–146 (1989).
16. E. Orr and G. Mallalieu, in

Coatings Technology Handbook II

, Chap. 71. D. Satas and A. Tracton,
Eds. New York: Marcel Dekker, 2000, pp. 595–608.

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76

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76

Pigment Dispersion

76.1 Introduction

76-

1
76.2 A Brief Introduction to Pigments

76-

2

76.3 The Dispersion Process

76-

4

76.4 The Role of Surface Energy

76-

6

76.5 Mechanisms for the Stabilization of Dispersion

76-

8

76.6 Surface Treatment

76-

9

76.7 Surface Treatment during Pigment Manufacture

76-

10
76.8 Surface Treatment of Pigments: Application

76-

11

76.9 The Characterization and Assessment of
Dispersion

76-

17
76.10 Conclusion

76-

17
References

76-

18

76.1 Introduction

The dispersion of pigments in fluid media is of great technological importance to the coatings manu-
facturers who deal with pigmented systems. The basic aim is to change the physical state of pigments to
achieve desired effects in specific application systems. The dispersion process involves the breaking down
and separation of the aggregated and agglomerated particles that are present in all pigments in their
normal form after their manufacture. Dispersion is not considered to be a process of pulverization but
rather a process of particle separation, homogeneous distribution of the particles in a medium, and
stabilization of the resultant system to prevent reaggregation, reagglomeration, flocculation, and settling.
The process of dispersion must be done efficiently and in the shortest time possible to draw out of the
pigment its maximum color properties at the least cost.
The topic of pigment dispersion in fluid media has been covered extensively in the literature.

1

−

6

Theoretical aspects of pigment dispersion apply equally well to inorganic and organic pigments. In this
chapter, the practical examples of surface treatments apply primarily to organic pigments, but similar
treatments can be carried out on inorganic pigments as well.

Theodore G. Vernardakis

BCM Inks USA, Inc.

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Pigment Definition • Pigment Particles
Pigment Wetting • Particle Deaggregation and
Surface Energy and Surface Area • Surface Energy and Pigment
Deagglomeration • Dispersion Stabilization
We tting • Surface Energy and Destabilization of the
Surfactants • Polymeric Dispersants • Surface Modifying Agents
Dispersion • Surface Energy and the Acid–Base Concept
Charge Stabilization • Steric or Entropic Stabilization
Organic Pigments • Inorganic Pigments