This document discusses factors that affect hull performance such as fouling, roughness, binder and biocide technologies, thickness, and idle time. It notes that biological fouling can increase hull roughness over time, leading to up to a 1% increase in hull resistance for every additional 10-20 micrometers of roughness. Newer binder technologies aim to better control biocide leaching rates to improve antifouling performance during idle conditions compared to traditional rosin-based approaches. The key factors for optimal hull performance are selecting a coating that matches the vessel's sailing patterns and idle time, maintaining a maximum roughness of 40 micrometers, and applying the coating at a minimum thickness of 250-300 micrometers.

2. Hull Performance ∝
Hull Threats
Physical Corrosion
Biological Fouling
Micro-Fouling
Macro-Fouling
1min 1-24h 1 week 2-3 weeks
Organic
Molecules
Bacteria Spores/Protozoa Larvae/Barnacles
Hard Fouling
Soft Fouling
How much is your idle time?
It’s all about Smoothness!
Hint: For each additional 10-20μm of average roughness, total hull resistance
increases by 1% for full form ships (e.g. tankers or bulk carriers)

3. Economical Problem
Bio invasive species are also transferred through hull fouling
Zebra Mussels in the US Great Lakes is a typical example of
invasive species from hull fouling
No Fouling Control System: Up to 150Kg of fouling per sqm
Loss of speed from moderate fouling can range 10% - 18%
5000 TEU Containership (150tn fuel per day @ 400$ per ton) would
save more than 1M$ annually for a 50μm smoother coating
Fuel is the cost – not paints or cleaning
Paint NOW or Pay LATER!
Emissions
10% of world fleet energy cost and GHG emissions come from
poor hull performance
No fouling protection would account for extra 210Mtn CO2 and
5,6Mtn SO2
Biological Problem

4. Cost?
Longevity?
Speed?
Thickness?
Regulatory?
Roughness?
Applicability?
Idle Promise?Sailing Area?

5. High Risk Med Risk Low Risk

6. G.L. Pickard, W.J. Emery, Descriptive Physical Oceanography: An Introduction, Pergamon Press, Oxford, UK, 1982.
Large variations on latitude (from -2oC up to +30oC)
Diurnal variations do not exceed 0,4oC in open seas
Salinity
Rather stable @ 3,46% - 3,48% up to a depth of 4000m
Some extremes observed in ice areas and close to river beds
Temperature

7. Resin
Pigments &
Fillers
Functional Additives
Solvents
Biocides:
Copper (I) Oxide Cu2O
Organic Biocides
Organic Inorganic Hybrids
Resins:
Pure Rosin
Silyl, Copper, Zinc Acrylates
Silicone Epoxies
SolidContent

8. The Old School
Formula Name Pros Cons
Cu2O, CuSCN
Copper (I) Oxide
Cuprous Oxide
Cuprous Thiocyanate
Broad Range
Low cost
Non-specific
Regulation Targeted
Requires High Loads
Galvanic Corrosion
CuP or C10H8N2O2S2Cu Copper Pyrithione
Broad Range
Cu(I) Booster
Low water solubility
High Cost
ZnP or C10H8N2O2S2Zn Zinc Pyrithione
Excellent Soft Fouling
Low water solubility
High Cost
Short Range
(C4H6N2S4Zn)n
C11H17Cl2NOS
Zineb
DCOIT
(Dichloroctylisothiazolinon
)
Effective Soft Fouling
Low Cost
Short Range
The New School
C12H5BrClF3N2
Tralopyril
(Econea)
Metal Free
Environmental Safe
Regulatory Approved
Long Idle Performance
High Cost
C13H16N2
Medetomidine
(Selektope)
Metal Free
Long Idle Performance
High Cost
Not Reg. Approved
High Toxicity
Good Antifouling Paints have more than 35% of Cuprous Oxide
New School performs better in extreme idle cond.
Copper Pyrithione is an excellent Copper (I) booster

9. Xi Zhou et al., Ind. Eng. Chem. Res., 2015, 54 (39), pp 9559–9565
Self-Polishing Coatings (SPC) – Rosin Based
A.G. Nurioglu et al., J. Mater. Chem. B, 2015, 3, 6547-6570
Advantages: Can perform in idle conditions
by controlling the solubility, stability, better
roughness control
Disadvantages: Hard to control biocide
leaching rate: Seawater finds it harder to
dissolve rosin-biocide in lower parts of the
coating
Biocides are dissolved in a hardly-soluble oily matrix (rosin) and blended
in insoluble polymer coating.

10. Self-Polishing Coatings (SPC) - Silyl Acrylate Based
Advantages: The hydrolysis could give the coatings self-smoothing properties Low
surface energy (20 – 30mN/m)
Disadvantages: A low erosion rate exhibited poor antifouling ability in a static
conditions, perform poorly against diatoms (=Slime before barnacles), Short-term
storage stability
Self-Polishing Coatings (SPC) – Copper or Zink Acrylate Based
Advantages: More Controlled Hydrolysis Rate
Disadvantages: A low erosion rate exhibited poor antifouling ability in a static
conditions, Salinity dependent, Short-term storage stability
SeaWater Insoluble
SeaWater Insoluble
SeaWater Soluble
SeaWater Soluble

11. Mechanisms Essential
Fouling Release Coatings (FRC) – Silicon Epoxy Hybrids
Non-polishing coatings that hinder solid adhesion of fouling on
their exposed surface.
2nd Generation FRCs contain biocides to boost AF properties
Require fast-steaming vessels and short cleaning intervals
Resistant to cleaning abrasion
Hard to apply and remove
FRCs will never become AF Coatings

12. Roughness is the key for not only friction decrease but
also better AF performance!
Increased roughness induces hydronamically stagnant water, which acts
as fouling nuclei.
Max Roughness Rz should be less than 40μm

13. Hull performance monitoring systems do pay off
Binder or Biocide?
Binder technology is completely different than biocide activity
A high tech binder system would perform poor with low copper (I) loads
Use paint schemes that combine different binder technologies
Thickness
Low thickness (DFT) reduces cost and useful lifetime expectancy
Minimum DFT for 60M performance is 250-300μm
Extended lifetime performance promise with low thickness will result
to inferior AF performance
Idle Time – Sailing Patterns
“Old fashioned” rosin based AFs perform better in long idle periods
and demanding sailing patterns
Avoid Zinc/Copper Acrylates next to freshwater environments
Surface Preparation
Underwater cleaning before Dry-Dockings saves huge on blasting!
Monitoring