• Journal of the Korean Society of Visualization
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• v.11 no.2
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• pp.18-26
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• 2013

An accurate and reliable performance evaluation technique is indispensable for the development of marine antifouling coatings. The existing standard practice is however, based on the visual observation of biofouling settlement area, which is prone to the subjective judgment of the inspector. In spite of the above mentioned importance, a systematic and objective fouling evaluation technique has not yet been introduced. In this study, a novel quantitative antifouling performance evaluation method for marine antifouling paints is devised based on the image analysis of panel immersion test results. The present image analysis method is to quantify settlement area for each fouling category by distinctive color. The fouling categories are set as unfouled, biofilm, green algae, brown algae, calcareous animal and spongy animal with specific HSL (Hue, Saturation, Lightness) color ranges. In order to assess the effectiveness of the proposed method, static immersion tests for three antifouling coatings were undertaken for two years.

• Journal of the Korean institute of surface engineering
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• v.55 no.6
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• pp.425-432
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• 2022

Antifouling paints that inhibit the attachment and contamination of marine organisms mainly use TBT compounds, but because of their toxic components, they cause ecosystem disturbance and environmental destruction problems, so It is necessary to research eco-friendly antifouling paints that are easy to maintain and effective antifouling technologies. In this study, physical surface treatment of silane coating and chemical antifouling technology were applied to the metal surface to secure the stability of the surface of the marine structure and inhibit the attachment and growth of marine organisms. Adhesion of marine organisms was evaluated according to the coating conditions through surface evaluation of the charged material for 15 months in the waters of the west coast of Korea. In accordance with ASTM D6990-05, antifouling properties fouling rates (FR) and physical degradation rates(PDR) were evaluated through visual inspection of the evaluation specimens. As a result of evaluating the antifouling performance of the coated surface, it was confirmed that the antifouling performance was maintained at the 50% level even after 15 months in the sample subjected to physical processing and silane coating.

• Journal of the Korea Institute of Building Construction
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• v.5 no.2 s.16
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• pp.97-105
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• 2005

Concrete structures in the marine environment often deteriorate in the early stage of their service life because of contact with various aggressive conditions. In recent years, the researches on the concrete in the marine environment have been carried out to increase their service life. In this experimental study, the concrete specimens were prepared with various adding contents of inorganic antifouling agent$(0\~3.0wt\%)$ composed of some fluosilicate solution. For evaluation of the properties of concretes containing inorganic antifouling agent, various tests such as setting time, slump loss, compressive strength, water absorption rate, fleering and thawing resistance and SEM of concrete, were conducted. As the results, physical and chemical properties of concretes were improved with an adding of inorganic antifouling agent. From the results of various tests, the optimal adding contents of antifouling agent was $1.0wt\%$.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.604-607
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• 2004

Concrete structures in the marine environment often deteriorate in the early stage of their service life because of contact with various aggressive conditions. In recent years, the study on the concrete in the marine environment are carried out to increase their service life. In this experimental study, the concrete specimens were prepared with various adding contents of inorganic antifouling agent$(0\~3.0wt\%)$ composed to some fluosilicate solution. For evaluatin of the physical and chemical properties of concretes containing inorganic antifouling agent, various tests such as setting time, slump loss, compressive strength, water absorption rate, freezing and thawing resistance and SEM micrographs of concrete, were conducted. As the results, physical and chemical properties of concretes were improved with an adding of inorganic antifouling agent. From the results of various tests, the optimal adding contents of antifouling agent was $1.0wt\%$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.1
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• pp.53-58
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• 2013

The active antifouling compounds coumarin and its derivatives were isolated from the cinnamon tree Cinnamomum loureiroi. The antifouling activities were determined using representative soft fouling organisms: the seaweed Ulvapertusa and diatom Navicula annexa. The chemical constituents with antifouling activities were identified as coumarin, hydroxylcoumarin, coumaric acid, and cinnamaldehyde by interpreting nuclear magnetic resonance, and high-resolution mass spectroscopy data. These compounds were isolated from 1.09 g of crude Cinnamomum sp. methanol extract, yielding approximately 18.4, 6.3, 9.8, and 14.7 mg of coumarin, hydroxylcoumarin, coumaric acid, and cinnamaldehyde, respectively. The compounds inhibited U. pertusa zoospores with $EC_{50}$ values of $0.13-0.25{\mu}g/mL$, and the diatom N. annexa with $EC_{50}$ of $0.21-0.81{\mu}g/mL$.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.134-135
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• 2013

In this study, the physical properties and antifouling were investigated to make the Marine growth antifouling coatings by blending of synthesized silicone resin and pigment with a low surface tension. To examine the film properties and foul release of the prepared coatings, film specimens were prepared with the prepared coatings and anti corrosion coatings. The test results showed that the silicone type antifouling coatings had very excellent antifouling properties rather than any other coatings because of the coating films had followed the low surface tension and elasticity, and prevention of adhesion for marine growth and mechanical adhesions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.1
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• pp.30-34
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• 2012

The filamentous bacterium Leucothrix mucor, an epiphyte of seaweed, showed antifouling activity against Ulva pertusa spore settlement and germling development. The chemical constituents representing the antifouling activity were identified as giffinisterone B and oleamide based on nuclear magnetic resonance (NMR) spectroscopy and mass spectroscopy (MS). Approximately 3.6 mg of giffinisterone B and 2.8 mg of oleamide were isolated from 1.6 g of Leucothrix mucor crude extract. Giffinisterone B fully inhibited spore settlement and germling development at $100{\mu}g/mL$. Oleamide inhibited spore settlement at $10{\mu}g/mL$ and germling development at $100{\mu}g/mL$.

• Journal of the Korean Applied Science and Technology
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• v.34 no.1
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• pp.152-162
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• 2017

A hydrophilic coating solution was prepared by adding a silane coupling agent and a nano-inorganic oxide in aqueous surfactant solution to increase the efficiency of photovoltaic power generation due to the introduction of antifogging and antifouling properties on the glass surface of the solar cell module. Addition of $Ludox^{(R)}$, a nano-inorganic oxide, to 1% hydrophilic coating solution showed improved hydrophilicity and excellent antifogging effect regardless of $Ludox^{(R)}$ concentration. However, the antifouling effect on the glass surface was showed only when Ludox was added more than 10%. In the case of addition of 0.7% of hydrolyzed TEOS at pH 4, the antifogging effect was maintained as a result of the steam test as well as the antifouling effect even after the coated glass surface was rubbed 100 times with a wet Kimwipe. In addition, from the surface roughness ($R_q$) calculated using AFM data, the higher surface roughness with irregular surface shape was obtained with the higher concentration of TEOS. The addition of 0.7% of TEOS showed relatively high surface roughness and well organized surface condition which can help to improve transmittance of light. In conclusion, $Ludox^{(R)}$ is not required only for the antifogging property. However, at least 10% of Ludox should be added to show antifouling effect and 0.7% of TEOS should be added for good durability.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.525-535
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• 2017

In order to produce hydrophilic coating solution, which has superior antifogging and antifouling effect on the glass surface of solar cell module as well as improving photovoltaic efficiency, nanosilica was dispersed in an aqueous solution of Tween 20 and fluorosurfactant composed of decafluorobutane and polyethylene glycol. The antifogging effect at high temperature was excellent for all the coating solutions containing nanosilica, but the antifouling effect was observed when the content of nanosilica was over 6 wt%. As the content of fluorosurfactant increased, the initial water contact angle slightly increased and the antifogging effect remained well until 500 wiping with wet $Wipeol^{(R)}$. The antifouling effect was also excellent regardless of the content of fluorosurfactant, thus 0.1 wt% of the fluorosurfactant was enough for a coating solution production. From the AFM results, when 0.1 wt% to 0.3 wt% of the fluoro surfactant was added, the fractal structure of the coated glass surface was clearly existed and contributed to the better antifouling effect. The transmittance of coated glass surface was highest in TL-1 coating solution containing 0.1 wt% of fluorosurfactant, and the addition of fluorosurfactant in a larger amount than 0.1 wt% did not improve the transmittance. This result is in good agreement with the previous AFM result which shows a high surface roughness as well as a fractal structure formation for the TL-1 coating solution.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.736-742
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• 2015

Cosmopolitan green macroalga, Ulva pertusa is a widely spread species in most coastal waters. This benthic alga is appearing on marine objectives causes significantly economical and social problems. To prevent fouling organisms, new antifouling (AF) agents, such as ziram, diruon, zinc pyrithione, copper pyrithione, DBNPA and triclosan are used. However, the evaluations of new antifouling system of those agents strongly need more information on algae species for considering environment effect. Therefore, the purpose of this study was to evaluate the activity of antifouling system using Ulva spores and Nitzschia pungens. In addition, new AFS were evaluated the toxicity of microalga, Nitzschia pungens. In the motility of Ulva spores, ziram and zinc pyrithione were shown 50% higher inhibition motility than diuron, copper pyritione, DBNPA and triclosan. Ziram was appered the highest AFS of Ulva sore attachment. Copper pyrithione at the concentration of $100{\mu}g/L$ was inhibited 80% growth rate comparison of control. In conclusion, each new AF agents showed their specific AF activities against marine organisms based on this work.