maintenance approach” of periodic spot touchup and an occasional recoat of
the entire surfacei sf ollowed.
Many coatings that provide good longterm protection are more difficult to
touch up or repair in the event of physical damage or localized failure. This
is particularly true of the thermosetting and zinc-rich coatings. Application
of as ubsequently applied paint coat to an older aged epoxy,u rethane, or
otherc atalyzedc oating oftenr esults in reduced adhesiont hatl eads
to peeling.
Thermoplastic coatings do not normally present this problem. Solvents of
afreshly applied thermoplastic coating soften and allow for intermolecular
mixing of the new and old coatings with good intercoat adhesion.
Heavilyp igmented coatings,s uch as zinc-rich, requirea gitated pots to
keep the pigment in suspension during application. Because of this, touchup
and repair of large areas is not recommended usingzinc-rich coatings unless
it is done by spray using an agitatedpot.
For them ost part, oil-based coatings (alkyds, epoxy esters, and
modifications thereof) have agreater tolerance for poor surface preparation
and an ability to wet, penetrate, and adhere to poorly prepared surfaces or
old coatings. Consequently,t hese coatings areo ften specified for these
purposes,e vent hought heyd on ot providea sl ongaterm of
corrosion protection.
References
1. I. Suzuki. 1989. Corrosion Resistant Coatings Te chnology,New York: Marcel Dekker.
2. D. Satas. 1991. Coatings Te chnology Handbook,N ew York: Marcel Dekker.
3. F. Mansfield. 1987. Corrosion Mechanisms,N ew York: MarcelD ekker.
4. F.C. Porter.1 994. Corrosion Resistance of Zinc and Zinc Alloys,N ew York: Marcel
Dekker.
5. P. A. Schweitzer.1988. Corrosion and Corrosion Protection Handbook,2nd ed., New
York: MarcelD ekker.
6. H.R. Copson. 1995. Report of subcommittee B-3 on Atmospheric Corrosion of
Nonferrous metals. ASIM Annual Meeting, Atlantic City,N J, June 25.
7. R. Leidheiser,Jr. 1987. Coatings, in Corrosion Mechanisms,F .Mansfield, Ed., New
York: MarcelD ekker,p p. 165–209.
8. K.B. Tator.1988. Coatings, in Corrosion and Corrosion Protection Handbook,2nd ed.,
P. A. Schweitzer,E d., New York: Marcel Dekker,p p. 453–489.
Coatings
485
CAT8247—CHAPTER 7—17/10/2006—15:04—TRGANESH—XMLM ODEL B–pp. 403–485
the entire surfacei sf ollowed.
Many coatings that provide good longterm protection are more difficult to
touch up or repair in the event of physical damage or localized failure. This
is particularly true of the thermosetting and zinc-rich coatings. Application
of as ubsequently applied paint coat to an older aged epoxy,u rethane, or
otherc atalyzedc oating oftenr esults in reduced adhesiont hatl eads
to peeling.
Thermoplastic coatings do not normally present this problem. Solvents of
afreshly applied thermoplastic coating soften and allow for intermolecular
mixing of the new and old coatings with good intercoat adhesion.
Heavilyp igmented coatings,s uch as zinc-rich, requirea gitated pots to
keep the pigment in suspension during application. Because of this, touchup
and repair of large areas is not recommended usingzinc-rich coatings unless
it is done by spray using an agitatedpot.
For them ost part, oil-based coatings (alkyds, epoxy esters, and
modifications thereof) have agreater tolerance for poor surface preparation
and an ability to wet, penetrate, and adhere to poorly prepared surfaces or
old coatings. Consequently,t hese coatings areo ften specified for these
purposes,e vent hought heyd on ot providea sl ongaterm of
corrosion protection.
References
1. I. Suzuki. 1989. Corrosion Resistant Coatings Te chnology,New York: Marcel Dekker.
2. D. Satas. 1991. Coatings Te chnology Handbook,N ew York: Marcel Dekker.
3. F. Mansfield. 1987. Corrosion Mechanisms,N ew York: MarcelD ekker.
4. F.C. Porter.1 994. Corrosion Resistance of Zinc and Zinc Alloys,N ew York: Marcel
Dekker.
5. P. A. Schweitzer.1988. Corrosion and Corrosion Protection Handbook,2nd ed., New
York: MarcelD ekker.
6. H.R. Copson. 1995. Report of subcommittee B-3 on Atmospheric Corrosion of
Nonferrous metals. ASIM Annual Meeting, Atlantic City,N J, June 25.
7. R. Leidheiser,Jr. 1987. Coatings, in Corrosion Mechanisms,F .Mansfield, Ed., New
York: MarcelD ekker,p p. 165–209.
8. K.B. Tator.1988. Coatings, in Corrosion and Corrosion Protection Handbook,2nd ed.,
P. A. Schweitzer,E d., New York: Marcel Dekker,p p. 453–489.
Coatings
485
CAT8247—CHAPTER 7—17/10/2006—15:04—TRGANESH—XMLM ODEL B–pp. 403–485