Aqueous antifouling composition

Abstract

The present invention provides an aqueous antifouling coating composition comprising: (a) a polymer binder containing a structural unit derived from an ethylenically unsaturated monomer; and (b) at least 1.0 wt%, based on the dry weight of the total coating composition, of a rosin ester wherein the rosin ester has a glass transition temperature (Tg) of less than 0 DEG C; wherein the coating composition comprises at least 5 wt% of water, relative to the total weight of the composition as a whole.

Description

Technical Field

[0001] The present invention relates to an antifouling coating composition, more particularly to an aqueous antifouling coating composition comprising a polymer binder and a rosin ester. The present invention further relates to a method of protecting an object from fouling, and to an object coated with the antifouling composition of the present invention. Background Art

[0002] Surfaces submerged in seawater are contaminated by marine organisms such as green and brown algae, barnacles, mussels, tube worms, etc. For marine structures such as ships, oil platforms, buoys, etc., this contamination is undesirable and has economic consequences. Contamination may lead to biodegradation of the surface, increased loads and accelerated corrosion. For ships, contamination increases frictional drag, which will result in reduced speed and / or increased fuel consumption.

[0003] In order to prevent the fixation and growth of marine organisms, antifouling paints are used. These paints usually contain a film-forming binder, together with different components such as pigments, fillers, additives and solvents, and biologically active substances (biocides). Biocides can be roughly divided into those active against soft fouling such as green and brown algae, grasses, mucus, and those active against hard fouling such as barnacles, mussels, tubeworms, etc.

[0004] Commercial ships (e.g. container ships, bulk carriers, tankers, passenger ships) typically operate in different waters, in different trades, with different degrees of activity (including idle periods). Antifouling coatings can provide good antifouling protection under all those conditions. The typical maintenance cycle for commercial ships is 30 to 90 months. The maintenance of submerged objects is expensive, so the antifouling coating applied should be effective for the specified maintenance cycle. It requires controlled degradation of the coating film, thereby providing a constant release of biocides to protect objects throughout the maintenance cycle and under various sailing conditions.

[0005] This can be best achieved by using a self-polishing antifouling coating with a controlled polishing rate. Polishing too quickly will result in rapid consumption of the coating film, leading to an unprotected surface. Polishing too slowly will result in inadequate release of the biocide, which is essential for effective protection from fouling. Controlled degradation over the useful life of the coating will provide a constant release of the biocide and thereby provide excellent antifouling protection.

[0006] In addition to these requirements, the coating industry has been facing stricter VOC regulations, which limit the amount of organic solvents that can be used in antifouling paints. The most common application methods for antifouling paints are airless spraying, brushing or roller coating. Importantly, paints can be applied by standard techniques, which means that coating compositions and paints have a certain viscosity level while minimizing their VOC content and still achieving satisfactory application characteristics. If additional solvents must be added to reduce viscosity when applying, the VOC limit may be exceeded.

[0007] It is a challenge to find coating compositions that comply with increasingly stringent VOC regulations and that also have controlled polishing properties, good mechanical properties and exhibit good antifouling protection.

[0008] One solution for achieving VOC compliant and more sustainable antifouling paints is to use waterborne paint technology. The waterborne paint market is likely to increase to provide more sustainable coatings to meet VOC / HAP regulations. Water-based paints are gaining popularity in the interior market due to low odor, easier cleaning, faster drying, and healthier for workers. For most applications, new technological advances have resulted in waterborne coatings that are closer in performance and durability to solventborne coatings.

[0009] Aqueous coatings are described, for example, in US 2021 / 0301153, US 4052354 and WO 2012 / 084758. These coatings include coatings based on (meth)acrylic binders.

[0010] JP 2007204687 discloses an aqueous release agent obtained by emulsifying a blend of a long-chain alkyl-based release agent and a rosin-based resin. The aqueous release agent is intended for use in an adhesive tape as a backside treatment layer of a substrate such as paper.

[0011] WO 2019 / 096928 discloses an antifouling coating composition for use on underwater surfaces to prevent marine biofouling. The composition is non-aqueous and comprises (i) an acrylic binder polymer and (ii) rosin.

[0012] However, there is a continuing need in the industry to develop new and improved coatings.

[0013] The present inventors have surprisingly found that if a specific class of rosin esters is included in a coating composition in addition to a polymeric binder containing structural units derived from ethylenically unsaturated monomers, a more controlled polishing and improved mechanical properties are observed. A more controlled polishing will provide a more controlled release of the biocide and thereby provide improved long-term antifouling properties.

[0014] The developed aqueous antifouling coating compositions show controlled polishing properties. In addition, they exhibit good mechanical properties (e.g. crack resistance, film-forming behavior). Summary of the invention

[0015] In one aspect, the present invention relates to an aqueous antifouling coating composition comprising:

[0016] (a) a polymer binder comprising structural units derived from ethylenically unsaturated monomers; and

[0017] (b) at least 1.0 wt% of a rosin ester, based on the dry weight of the total coating composition, wherein the rosin ester has a glass transition temperature (Tg) of less than 0°C;

[0018] Therein, the coating composition comprises at least 5 wt % of water relative to the total weight of the composition as a whole.

[0019] In another aspect, the present invention provides a method for applying an aqueous antifouling coating composition to a substrate, comprising applying (eg by spraying) the aqueous antifouling coating composition as defined above to the substrate and allowing the coating composition to dry.

[0020] In another aspect, the present invention provides a method for protecting an object from fouling, the method comprising coating at least a portion of the object subject to fouling with an antifouling coating composition as defined above.

[0021] In another aspect, the present invention provides a substrate coated with an aqueous antifouling coating composition as defined above, wherein the coating composition has been dried.

[0022] In yet another aspect, the present invention provides use of a rosin ester having a glass transition temperature (Tg) of less than 0° C. for increasing the polishing rate of an aqueous antifouling coating composition, preferably an antifouling coating composition comprising a polymer binder comprising structural units derived from ethylenically unsaturated monomers, more preferably an antifouling coating composition comprising a polymer binder comprising (meth)acrylic acid and / or (meth)acrylate monomers.

[0023] definition

[0024] The term "marine antifouling coating composition", "antifouling coating composition" or simply "coating composition" refers to a composition that, when applied to a surface, prevents or minimizes the growth of marine organisms on a surface.

[0025] As used herein, the term "aqueous composition" refers to a composition comprising water as the main solvent. Typically, water accounts for at least 70 wt %, preferably greater than 80 wt %, and particularly preferably greater than 90 wt % of the solvent used.

[0026] As used herein, the term "paint" refers to a composition comprising the antifouling coating composition described herein and optionally a solvent ready for use (e.g., for spraying). Thus, the antifouling coating composition itself may be a paint or the antifouling coating composition may be a concentrate to which a solvent is added to produce a paint.

[0027] The term "(meth)acrylate" refers to methacrylate or acrylate.

[0028] The term "hydrocarbyl" refers to any group containing only C and H atoms, and thus encompasses alkyl, alkenyl, aryl, cycloalkyl, aralkyl, and the like.

[0029] As used herein, the terms "resin acid" and "rosin acid" refer to the mixture of carboxylic acids present in the resin.

[0030] The term "binder system" defines that portion of the composition which includes the polymeric binder and any other polymers, resins or components which together form the matrix which gives the composition substance and strength. The rosin esters of the present invention are considered part of a binder system.

[0031] The term "Tg" refers to the glass transition temperature obtained by differential scanning calorimetry (DSC) measurement.

[0032] When the wt % of a given monomer is provided, the wt % is relative to the sum (weight) of each monomer present in the copolymer.

[0033] Unless otherwise indicated, the term "wt % based on the total weight of the composition" refers to the wt % of a component present in the final, ready-to-use composition.

[0034] The term "wt % based on the total dry weight of the composition" refers to the wt % of a component present in the composition relative to the total weight of the components in the composition excluding solvent.

[0035] As used herein, the term "dispersion" refers to a fine dispersion of particles or droplets dispersed in a continuous liquid phase. Typically, the continuous liquid phase is water. Therefore, the dispersions employed in the present invention may also be referred to as "aqueous dispersions," meaning that they are dispersions in which the continuous phase (i.e., solvent) is water.

[0036] Droplets dispersed in water may be referred to as an emulsion. As used herein, the term emulsion refers to a fine dispersion of droplets of one liquid in another liquid in which it is not soluble or miscible. In the present invention, the term "dispersion" refers to both particles and droplets (emulsion) dispersed in water.

[0037] As used herein, the term "volatile organic compound (VOC)" refers to an organic compound having a boiling point of 250°C or less at 101.3 kPa.

[0038] As used herein, "antifouling agent" or "biocide" refers to a biologically active compound or mixture of biologically active compounds that prevents marine organisms from fixing to a surface, and / or prevents the growth of marine organisms on a surface, and / or promotes the shedding of marine organisms on a surface. These terms can be used interchangeably. The European Biocidal Products Regulation (BPR) defines a biocide as an active substance intended to destroy, deter, render harmless, prevent the action of or otherwise exert a control over any harmful organism by chemical or biological means. DETAILED DESCRIPTION

[0039] The present invention relates to a novel aqueous antifouling coating composition comprising (a) a polymer binder containing structural units derived from ethylenically unsaturated monomers and (b) a rosin ester.

[0040] Polymer Binders

[0041] The coating composition of the present invention comprises a polymeric binder comprising structural units derived from ethylenically unsaturated monomers.The polymeric binder defined above will be referred to herein as "polymeric binder".

[0042] Examples of suitable ethylenically unsaturated monomers are (meth)acrylic acid, (meth)acrylic esters, (meth)acrylamide, vinyl chloride, vinyl esters, vinyl acetate, vinyl propionate, maleic acid, itaconic acid, vinyl alcohol, styrene, α-methylstyrene, alkyl vinyl ethers, vinylpyrrolidone, N-vinylcaprolactam, N-methyl-N-vinylacetamide and (meth)acrylonitrile.

[0043] Preferably, the ethylenically unsaturated monomer is selected from (meth)acrylic acid, (meth)acrylic acid esters, (meth)acrylic acid amides and vinyl esters, such as vinyl acetate and vinyl neodecanoate.

[0044] In a particularly preferred embodiment, the ethylenically unsaturated monomers are selected from (meth)acrylic acid and (meth)acrylic acid esters.

[0045] Examples of (meth)acrylate monomers include:

[0046] Alkyl or cycloalkyl (meth)acrylic acid esters having 1 to 18 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate and cyclohexyl (meth)acrylate;

[0047] Alkoxyalkyl (meth)acrylic acid esters having 2 to 18 carbon atoms, such as methoxybutyl (meth)acrylate, methoxyethyl (meth)acrylate, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, and ethoxybutyl (meth)acrylate;

[0048] Dialkylaminoalkyl (meth)acrylates, such as dimethylaminoethyl (meth)acrylate, 2-(diethylamino)ethyl (meth)acrylate, 2-(diisopropylamino)ethyl (meth)acrylate, 2-(tert-butylamino)ethyl (meth)acrylate, 4-dimethylaminobutyl (meth)acrylate and dimethylaminopropyl (meth)acrylate;

[0049] Hydroxyalkyl (meth)acrylates, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxy-1-methylethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate and hydroxyisobutyl (meth)acrylate;

[0050] Glycidyl (meth)acrylate, (2,2-dimethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate;

[0051] (Meth)acrylate monomers including cyclic amines, such as (meth)acryloyl-2-pyrrolidone;

[0052] (Meth)acrylate monomers containing polysiloxane groups, such as monomethacryloxypropyl-terminated polydimethylsiloxanes, such as α-methacryloxypropyl-ω-butyl polydimethylsiloxane, α-methacryloxypropyl-ω-trimethylsilyl polydimethylsiloxane, α-methacryloxyethyl-ω-trimethylsilyl polydimethylsiloxane, α-acryloxypropyl-ω-butyl polydimethylsiloxane, α-acryloxypropyl-ω-trimethylsilyl polydimethylsiloxane, α-acryloxyethyl-ω-trimethylsilyl polydimethylsiloxane. Representative examples of commercially available monomers containing polysiloxane groups include X-22-174ASX, X22-174BX, KF-2012, X-22-2426 and X-22-2404 from Shin-Etsu, Silaplane FM-0711, Silaplane FM-0721, Silaplane FM-0725 from JNC Corporation, PS560 from United Chemical Technologies, and MCR-M07, MCR-M11, MCR-M17, MCR-M22 and MCR-V41 from Gelest;

[0053] (Meth)acrylic monomers containing polyether groups, such as poly(ethylene glycol) methyl ether (meth)acrylate, poly(propylene glycol) methyl ether (meth)acrylate, poly(ethylene glycol) ethyl ether (meth)acrylate, poly(propylene glycol) ethyl ether (meth)acrylate, poly(ethylene glycol) (meth)acrylate, poly(propylene glycol) (meth)acrylate. Representative examples of commercially available monomers include Visiomer MPEG 750MA W, Visiomer MPEG 1005MA W, Visiomer MPEG 2005MA W, Visiomer MPEG 5005MAW from Evonik, Bisomer PPA6, Bisomer PEA6, Bisomer PEM6, Bisomer PPM5, Bisomer PEM63P, BisomerMPEG350MA, BisomerMPEG550MA, Bisomer S10W, Bisomer S20W from Geo Speciality Chemicals, SR550MPEG350MA, SR552MPEG500MA from Sartomer, and RPEG 750 from Ineos Oxide;

[0054] Hydrolyzable (meth)acrylate monomers, such as silyl (meth)acrylate monomers and metal ester (meth)acrylate monomers. Examples of such monomers are trialkylsilyl monomers such as triisopropylsilyl (meth)acrylate, zinc (meth)acrylate and zinc (meth)acrylate acetate, copper (meth)acrylate and copper (meth)acrylate acetate.

[0055] In a particularly preferred embodiment, the polymer binder comprises residues of at least one, preferably at least two, monomers of formula (I):

[0056]

[0057] Where R 1 is H or CH3;

[0058] R 2 is H or an optionally linear, branched or cyclic substituted C 1-18 Alkyl, wherein the substituent is selected from OH, OR 3 and N(R 4 )2; and

[0059] R 3 Selected from C 1-8 Alkyl and C 3-8 Cycloalkyl.

[0060] R 4 Each independently selected from H, C 1-8 Alkyl and C 3-8 Cycloalkyl;

[0061] It should be understood that the polymer binder of the present invention may be a copolymer comprising multiple monomers as described above.

[0062] The polymer binder of the present invention preferably comprises at least 50 wt%, preferably at least 70 wt%, more preferably at least 80 wt% of structural units derived from ethylenically unsaturated monomers, relative to the total weight of the polymer binder. In a preferred embodiment, the polymer binder of the present invention comprises at least 95 wt%, preferably 100 wt%, of structural units derived from ethylenically unsaturated monomers.

[0063] The polymer binder of the present invention preferably comprises (meth)acrylic acid and / or (meth)acrylate monomers. Preferably, the polymer binder of the present invention comprises at least 15 wt%, preferably at least 20 wt%, more preferably at least 40 wt%, still more preferably at least 55 wt% of (meth)acrylic acid and / or (meth)acrylate monomers relative to the total weight of the polymer binder. Typically, the (meth)acrylic acid and / or (meth)acrylate monomers are present in an amount of 99.9 wt% or less, more preferably 99.5 wt% or less, relative to the total weight of the polymer binder.

[0064] The amount of each structural unit can be determined, for example, by nuclear magnetic resonance spectroscopy (NMR) or pyrolysis gas chromatography mass spectrometry (Pyro-GC / MS). Information on the wt% of (meth)acrylic acid and / or (meth)acrylate moieties in commercially available polymer binders is also often readily available from suppliers.

[0065] The polymer binder of the present invention can be produced by methods known in the art. Generally, this involves appropriately selecting one or more ethylenically unsaturated monomers in an amount taking into account, for example, structural units and weight average molecular weight, and then polymerizing the monomers using known methods such as emulsion polymerization.

[0066] The amount of the polymer binder in the coating composition is preferably 1.0 to 40 wt %, more preferably 2.0 to 35 wt %, further preferably 2.5 to 25 wt %, based on the total dry weight of the coating composition.

[0067] The glass transition temperature (Tg) of the polymer binder is not particularly limited, and may be, for example, less than 50°C.

[0068] In a particularly preferred embodiment, the polymeric binder of the present invention is in the form of a dispersion.

[0069] The polymer binder is typically present in the dispersion in the form of particles or droplets having an average particle size of 4 to 1000 nm, preferably 25 to 400 nm, more preferably 50 to 350 nm, such as 100 to 300 nm. The "average particle size" referred to in this context is the Z average particle size, which is understood to be the intensity-weighted average hydrodynamic diameter described in ISO 22412:2017. It should be understood that in this context, the polymer binder particles form the dispersed phase of the dispersion.

[0070] The polymer binder droplets or particles preferably comprise 10 to 80 wt% of the dispersion relative to the total weight of the dispersion as a whole. A typical wt% range may be 35 to 60 wt%, such as 40 to 55 wt%, relative to the total weight of the dispersion as a whole.

[0071] Except polymer binder droplet or particle, dispersion also comprises aqueous solvent (i.e. continuous phase).It should be understood that aqueous solvent is a solvent comprising water (preferably consisting of water).Therefore, the dispersion mentioned here can be referred to as aqueous dispersion.The aqueous dispersion of polymer binder is a dispersion in which polymer binder is dispersed in a dispersion medium (hereinafter also referred to as "aqueous medium") comprising water.

[0072] The aqueous medium is not particularly limited as long as it includes water; however, relative to the gross weight of the aqueous medium, the water content in the aqueous medium is preferably 50 to 100wt%, and more preferably 60 to 90wt%. In a preferred embodiment, the water content in the aqueous medium is 100wt%, and for example the aqueous medium is composed of water. The aqueous medium may include a medium other than water, and examples of such medium include acetone, methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, diacetone alcohol, dioxane, ethylene glycol, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dipropylene glycol monomethyl ether (Dowanol DPM), ethylene glycol monopropyl ether, and ethylene glycol monohexyl ether. One or more of these may be used.

[0073] The solvent, preferably water, represents 10 to 70% of the volume of the dispersion relative to the total volume of the dispersion as a whole. Typical vol% ranges may be 20 to 65%, such as 30 to 60%, relative to the total volume of the dispersion as a whole.

[0074] The dispersion may be prepared by any suitable method known in the art.

[0075] The dispersion may contain a surfactant. The surfactant may be nonionic, anionic, cationic or amphoteric.

[0076] Examples of nonionic surfactants are alkylphenoxy ethers, polyalkylene glycols, polyoxyalkylene sorbitan monooleates, polyvinyl alcohols, polyvinyl esters, polyether siloxanes, fatty alcohol ethoxylates and sorbitan stearates. Preferred nonionic emulsifiers are polyalkylene glycols such as polyoxyethylene-polyoxypropylene copolymers and fatty alcohol ethoxylates.

[0077] Examples of anionic surfactants are alkyl-, aryl-, alkylaryl-sulfates, sulfonates, phosphates, sulfosuccinates, sulfosuccinamates, sulfoacetates and amino acid derivatives.

[0078] Particularly preferred anionic surfactants are alkyl sulfates, polyoxyethylene alkyl ether sulfates, unsaturated aliphatic sulfonates and hydroxylated aliphatic sulfonates. The alkyl mentioned here can be exemplified by medium and higher alkyls, such as decyl, undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl, etc. Unsaturated aliphatic groups can be exemplified by oleyl, nonenyl and octynyl. Counterions can be exemplified by sodium ions, potassium ions, lithium ions and ammonium ions, wherein sodium ions are usually used.

[0079] The cationic surfactants can be exemplified by quaternary ammonium salt type surfactants such as alkyl trimethyl ammonium salts, such as octadecyl trimethyl ammonium chloride and hexadecyl trimethyl ammonium chloride, and dialkyl dimethyl ammonium salts, such as dioctadecyl dimethyl ammonium chloride, dihexadecyl dimethyl ammonium chloride and didecyl dimethyl ammonium chloride.

[0080] Examples of the amphoteric surfactant include alkyl betaines and alkyl imidazolines.

[0081] The dispersion may also contain a crosslinking agent, a curing catalyst, a defoamer, a rheology modifier, and a pH adjuster. Suitable defoamers, rheology modifiers, and pH adjusters are described further under additives.

[0082] From the viewpoint of the stability of the dispersion, the solid volume is preferably 30% or more, more preferably 40 wt% or more relative to the total volume of the dispersion. Typically, the solid volume is 80% or less, preferably 70% or less relative to the total solid volume of the dispersion as a whole.

[0083] Examples of suitable commercially available dispersions include PRIMAL TM AC-337、PRIMAL TM SF-021 and MAINCOTE TM 1071.

[0084] The aqueous dispersion of the polymer binder can be prepared by dispersing the polymer binder with a surfactant to form a dispersion. In addition, the dispersion can be directly prepared by forming the polymer binder through the emulsion polymerization of the monomer. The surfactant is not particularly limited and can be suitably selected from the above-described cationic surfactants, anionic surfactants and nonionic surfactants.

[0085] The dispersion of polymer binder preferably comprises 2-45 wt% of the antifouling coating composition relative to the total weight of the composition as a whole. Typical wt% ranges may be 3 to 40 wt%, such as 5 to 35 wt%, relative to the total weight of the composition as a whole.

[0086] Rosin ester

[0087] The antifouling coating composition of the present invention further comprises a rosin ester. It should be understood that the rosin ester of the present invention is also considered to be part of the binder system.

[0088] Rosin esters are made from rosin acid by converting the carboxylic acid groups of the rosin acid into ester groups, for example by reacting the carboxylic acid with an alcohol.

[0089] Rosin acids are also known as resin acids. It should be understood that rosin acids are derived from natural sources and therefore they are usually present as a mixture of acids. Examples of rosin acids are abietic acid, neoabietic acid, dehydroabietic acid, palustric acid, pimaric acid, levopimaric acid, isopimaric acid and sandaracopimaric acid. Representative examples of rosin acid sources are gum rosin, wood rosin and tall oil rosin.

[0090] Abietic acid derivatives such as hydrogenated abietic acid, partially hydrogenated abietic acid, dimerized abietic acid, and modified abietic acid (eg, maleic acid- and fumaric acid-modified abietic acid) can also be used to make rosin esters.

[0091] After reaction with the rosin acid, the molecular weight and functionality of the alcohol will determine the Tg of the resulting rosin ester.

[0092] The rosin esters of the present invention have a glass transition temperature (Tg) of less than 0°C. The Tg is obtained by differential scanning calorimetry (DSC) measurement. Typically, the measurement is performed by running a heating-cooling-heating program in a temperature range from -80°C to 150°C at a heating rate of 10°C / min and a cooling rate of 10°C / min and using an empty pan as a reference. The inflection point of the glass transition range of the second heating is reported as the Tg of the rosin ester as defined in ASTM E1356-08.

[0093] In practice, a Tg of less than 0°C generally means that the rosin ester is in a liquid state at room temperature (ie, a temperature in the range of 18°C ​​to 25°C). In a preferred embodiment, the rosin ester has a Tg of less than -5°C, such as less than -10°C.

[0094] Without wishing to be bound by theory, it is believed that rosin esters having a Tg of less than 0°C (and therefore, being generally liquid at room temperature) will provide a plasticizing effect resulting in less cracking and increase the polish rate of the coating, whereas rosin esters having a Tg above this (and, being generally solid at room temperature) will not have a positive effect on the polish rate and will significantly reduce the polish compared to coating compositions in which the binder system comprises only a polymeric binder.

[0095] The reaction of rosin acids with monofunctional and difunctional alcohols will generally produce rosin esters having a Tg of less than 0° C. Examples of suitable alcohols are methanol, ethanol and triethylene glycol.

[0096] The reaction of rosin acid with tri- and tetrafunctional alcohols such as glycerol and pentaerythritol will generally give rosin esters having a Tg above 0°C.

[0097] Preferably, the rosin ester of the present invention is made from abietic acid or abietic acid derivative and a mono- or difunctional alcohol.

[0098] Any rosin ester that meets the above Tg requirements can be used. Preferred rosin esters include methyl ester or triethylene glycol ester of rosin acid.

[0099] Examples of commercially available suitable rosin esters are Granolite TEG (triethylene glycol ester of rosin, supplied by DRT, viscosity 600 DPa.s at 20°C, acid value 12-15 mg KOH / g, Gardner color 6 (50 resin / 50 toluene)), Granolite M (methyl ester of rosin, supplied by DRT, viscosity 3500 mPa.s at 30°C, maximum acid value 9 mg KOH / g, Gardner color maximum 6 (50 resin / 50 toluene)), (wood rosin methyl ester, supplied by DRT, liquid, Gardner color 6, maximum acid value 8 mgKOH / g), liquid rosin ester LRE-1 (supplied by Resin Chemicals, polyol esterified gum rosin, viscosity 20-40 mPa.s at 30°C, acid value 20 mg KOH / g, Gardner color 8), Abalyn TM DE (rosin methyl ester, supplied by Eastman, viscous liquid, acid value 5mgKOH / g, Gardner color 4), Dertoline DEG 2 (rosin esterified with diethylene glycol, supplied by DRT, liquid, acid value 13mgKOH / g, Gardner color 2.5, Tg-7, softening point 37), D (methyl ester of partially hydrogenated rosin, supplied by DRT, liquid, Tg-30, Gardner color 2, acid value 6 mgKOH / g), Neutac liquid rosin ester (Neutac supplied by Newport resins, a variety of liquid rosin esters available, such as Neutac 14277, Neutac MER-L and MEHR-L).

[0100] A single rosin ester as defined above may be used, or a mixture of two or more such rosin esters.The rosin esters may be used in combination with one or more rosin acids.

[0101] In order to ensure adequate polishing and mechanical properties, the amount of rosin ester should be at least 1.0 wt % relative to the total dry weight of the coating composition. Typical wt % ranges for rosin esters relative to the total dry weight of the coating composition are 1.0 to 30 wt %, such as 1.2 to 25 wt %, more preferably 1.5 to 20 wt %. When the coating composition comprises more than one rosin ester, these wt % ranges are understood to correspond to the total amount of all rosin esters present.

[0102] Preferably, the ratio between the rosin ester and the polymer binder is greater than 5:95, such as 10:90 or greater.

[0103] In particularly preferred embodiments, the rosin ester is in the form of a dispersion.

[0104] The rosin ester is typically present in the dispersion in the form of droplets or particles having an average particle size of 50 to 1500 nm, preferably 100 to 1200 nm, more preferably 150 to 1000 nm. The "average particle size" referred to in this context is the Z-average particle size, which should be understood as the intensity-weighted average hydrodynamic diameter described in ISO 22412:2017.

[0105] It should be understood in this context that the rosin ester droplets or particles form the dispersed phase of the dispersion.

[0106] The rosin ester droplets or particles preferably comprise 30 to 90 wt % of the dispersion relative to the total weight of the dispersion as a whole. A typical wt % range may be 35 to 80 wt %, such as 40 to 70 wt %, relative to the total weight of the dispersion as a whole.

[0107] In addition to rosin ester droplets or particles, the dispersion also includes an aqueous solvent (i.e., a continuous phase). It should be understood that an aqueous solvent is a solvent comprising water (preferably consisting of water). Therefore, the dispersion mentioned herein can be referred to as an aqueous dispersion. An aqueous dispersion of rosin ester is a dispersion in which the rosin ester is dispersed in a dispersion medium (hereinafter, also referred to as an "aqueous medium") comprising water.

[0108] The aqueous medium is as defined above for the dispersion of the polymeric binder.

[0109] The solvent (preferably water) comprises 10 to 70 wt% of the dispersion relative to the total weight of the dispersion as a whole. A typical wt% range may be 20 to 65 wt%, such as 30 to 60 wt%, relative to the total weight of the dispersion as a whole. The dispersion may be prepared by any suitable known method in the art.

[0110] The dispersion may include surfactants, such as those defined above for dispersions of polymeric binders. The dispersion may also include defoamers, preservatives, pH adjusters, and rheology modifiers. Suitable defoamers, rheology modifiers, preservatives, and pH adjusters are further described under additives.

[0111] From the viewpoint of dispersion stability, the solids are preferably 30 wt% or more, more preferably 40 wt% or more, even more preferably 50 wt% or more, relative to the total weight of the dispersion or emulsion. Typically, the solids content is 80 wt% or less, preferably 70 wt% or less, relative to the total weight of the dispersion as a whole.

[0112] The dispersion of rosin ester preferably comprises 0.5 to 30 wt% of the antifouling coating composition relative to the total weight of the composition as a whole. A typical wt% range may be 1.0 to 25 wt%, such as 2.0 to 20 wt%, relative to the total weight of the composition as a whole.

[0113] Abietic acid and abietic acid derivatives

[0114] In addition to the above-mentioned polymer binder and rosin ester, the coating composition of the present invention may optionally contain rosin acid and / or rosin acid derivatives. Rosin acid can be used to increase the polishing rate of the coating composition. It should be understood that, when present, rosin acid and / or rosin acid derivatives are also considered to be part of the binder system.

[0115] Rosin acids are also known as resin acids. It will be appreciated that rosin acids are derived from natural sources and therefore they are typically present as a mixture of acids. Examples of rosin acids are abietic acid, neoabietic acid, dehydroabietic acid, palustric acid, pimaric acid, levopimaric acid, isopimaric acid and sandaracopimaric acid. Representative examples of rosin acid sources are gum rosin, wood rosin and tall oil rosin. Gum rosin, also known as colophony and colophonium, is particularly preferred. Preferred rosin acids are those containing greater than 85% of rosin acid and still more preferably greater than 90% of rosin acid.

[0116] Commercial grades of rosin acid are often classified according to their color by assigning letters on the color scale XC (lightest), XB, XA, X, WW, WG, N, M, K, I, H, G, F, E, D (darkest) as described in ASTM D509. Preferred color grades for the compositions of the present invention are X, WW, WG, N, M, K, I, and more preferably WW. Commercial grades of rosin acid typically have an acid value of from 155 to 180 mg KOH / g as specified in ASTM D465. Preferred rosins for use in the compositions of the present invention have an acid value of from 155 to 180 mg KOH / g, more preferably from 160 to 175 mg KOH / g, and even more preferably from 160 to 170 mg KOH / g. Commercial grades of rosin typically have a softening point (ring and ball method) of 70° C. to 80° C. as specified in ASTM E28. Preferred rosins for use in the compositions of the present invention have a softening point of 70° C. to 80° C., more preferably from 75° C. to 80° C.

[0117] In a preferred embodiment, the coating composition of the invention comprises abietic acid.Typical amounts of abietic acid (when present) are from 0.1 wt% to 15 wt%, such as from 0.5 wt% to 10 wt%, relative to the dry weight of the total composition.

[0118] If present, the ratio between rosin ester and rosin acid can be, for example, 3:1, 2:1, 1:1, 1:2 or 1:3.

[0119] If present, the ratio between polymer binder, rosin ester and rosin acid may be, for example, 2:1:1, or 1:2:1, 1:1:2.

[0120] The rosin acid is preferably dispersed in water as described above for the rosin esters.

[0121] When present, the rosin acid is typically present in the dispersion in the form of droplets or particles having an average particle size of 50 to 1500 nm, preferably 100 to 1200 nm, more preferably 150 to 1000 nm. The "average particle size" referred to in this context is the Z-average particle size, which should be understood as the intensity-weighted average hydrodynamic diameter described in ISO 22412:2017.

[0122] It should be understood that in this context, the abietic acid droplets or particles form the dispersed phase of the dispersion.

[0123] The rosin acid droplets or particles preferably comprise 30 to 90 wt% of the dispersion relative to the total weight of the dispersion as a whole. A typical wt% range may be 35 to 80 wt%, such as 40 to 70 wt%, relative to the total weight of the dispersion as a whole.

[0124] In addition to the rosin acid droplets or particles, the dispersion also comprises an aqueous solvent (i.e., a continuous phase). It should be understood that an aqueous solvent is a solvent comprising (preferably consisting of) water. Therefore, the dispersion referred to herein may be referred to as an aqueous dispersion. An aqueous dispersion of rosin acid is a dispersion in which rosin acid is dispersed in a dispersion medium comprising water (hereinafter, also referred to as an "aqueous medium").

[0125] The aqueous medium is as defined above for the dispersion of the polymeric binder.

[0126] The solvent (preferably water) comprises 10 to 70 wt % of the dispersion relative to the total weight of the dispersion as a whole. A typical wt % range may be 20 to 65 wt %, such as 30 to 60 wt %, relative to the total weight of the dispersion as a whole. The dispersion may be prepared by any suitable known method in the art.

[0127] The dispersion of rosin acid may also contain surfactants, defoamers, rheology modifiers and pH adjusters. Suitable defoamers, rheology modifiers and pH adjusters are further described under additives. Suitable surfactants are as described for the above polymer binder.

[0128] Abietic acid derivatives such as hydrogenated abietic acid, partially hydrogenated abietic acid, dimerized abietic acid and modified abietic acid (e.g. maleic acid and fumaric acid modified abietic acid) may also be present in the coating composition of the present invention. When present, the abietic acid derivative is preferably dispersed in water, as described above for abietic acid.

[0129] Typical amounts of abietic acid derivatives (when present) are from 0.1 wt% to 15 wt%, for example from 0.5 wt% to 10 wt%, relative to the dry weight of the total composition.

[0130] Metal carboxylates of rosin acid and rosin acid derivatives may also be present in the antifouling coating composition of the present invention. Examples of metal carboxylates include alkali metal salts, such as sodium and potassium carboxylates, alkaline earth metal carboxylates, such as magnesium carboxylates and calcium carboxylates, or transition metal carboxylates, such as copper carboxylates and zinc carboxylates. Transition metal carboxylates are preferred, such as zinc rosin acid (zinc rosin acid) and copper rosin acid (copper rosin acid). The metal carboxylates may be added directly to the antifouling coating composition or may be generated in situ in the antifouling coating composition.

[0131] Other adhesive components

[0132] In addition to the polymeric binders, rosin esters and optionally rosin acids described above, additional binders may also be used to adjust the properties of the antifouling coating composition. Examples of binders that may be used include:

[0133] Poly(ethylene glycol) copolymers;

[0134] Saturated aliphatic polyesters such as poly(lactic acid), poly(glycolic acid), poly(2-hydroxybutyric acid), poly(3-hydroxybutyric acid), poly(4-hydroxyvaleric acid), polycaprolactone, and aliphatic polyester copolymers containing two or more units selected from the foregoing units; and

[0135] Polymeric plasticizers from any of the polymer groups specified above.

[0136] Further examples of other binder components that may be present in the antifouling coating composition of the present invention include:

[0137] Polyurethane adhesive system;

[0138] Hydrocarbon resins, such as hydrocarbon resins formed solely by polymerizing at least one monomer selected from C5 aliphatic monomers, C9 aromatic monomers, indene coumarone monomers or terpenes or mixtures thereof;

[0139] and monocarboxylic acids other than the above-mentioned rosin acid.

[0140] Examples of suitable monocarboxylic acids are C6-C 20 Cyclic monocarboxylic acid, C5-C 24Non-cyclic aliphatic monocarboxylic acid, C7-C 20 Aromatic monocarboxylic acids, derivatives of any monocarboxylic acids and mixtures thereof.

[0141] Derivatives of monocarboxylic acids include metal salts of monocarboxylic acids, such as alkali metal carboxylates, alkaline earth metal carboxylates (e.g. calcium carboxylates, magnesium carboxylates) and transition metal carboxylates (e.g. zinc carboxylates, copper carboxylates). Preferably, the metal carboxylates are transition metal carboxylates, and particularly preferably, the metal carboxylates are zinc carboxylates or copper carboxylates. The metal carboxylates can be directly added to the antifouling coating composition or generated in situ in the antifouling coating composition.

[0142] C6-C 20 Representative examples of cyclic monocarboxylic acids include cycloalkanoic acid, 1,4-dimethyl-5-(3-methyl-2-butenyl)-3-cyclohexen-1-yl carboxylic acid, 1,3-dimethyl-2-(3-methyl-2-butenyl)-3-cyclohexen-1-yl carboxylic acid, 1,2,3-trimethyl-5-(1-methyl-2-propenyl)-3-cyclohexen-1-yl-carboxylic acid, 1,4,5-trimethyl-2-(2-methyl-2-propenyl)-3-cyclohexen-1-yl-carboxylic acid, 1,4,5-trimethyl-2-(2-methyl-1-propenyl)-3-cyclohexen-1-yl-carboxylic acid, 1,5,6-trimethyl-3-(2-methyl-1-propenyl)-4-cyclohexen-1-yl-carboxylic acid , 1-methyl-4-(4-methyl-3-pentenyl)-4-cyclohexen-1-yl-carboxylic acid, 1-methyl-3-(4-methyl-3-pentenyl)-3-cyclohexen-1-yl-carboxylic acid, 2-methoxycarbonyl-3-(2-methyl-1-propenyl)-5,6-dimethyl-4-cyclohexen-1-yl-carboxylic acid, 1-isopropyl-4-methylbicyclo[2,2,2]2-octen-5-yl-carboxylic acid, 1-isopropyl-4-methyl-bicyclo[2,2,2]2-octen-6-yl-carboxylic acid, 6-isopropyl-3-methyl-bicyclo[2,2,2]2-octen-8-yl-carboxylic acid and 6-isopropyl-3-methyl-bicyclo[2,2,2]2-octen-7-yl-carboxylic acid.

[0143] C5-C 24 Representative examples of non-cyclic aliphatic monocarboxylic acids include versatic acid, neodecanoic acid, 2,2,3,5-tetramethylhexanoic acid, 2,4-dimethyl-2-isopropylpentanoic acid, 2,5-dimethyl-2-ethylhexanoic acid, 2,2-dimethyloctanoic acid, 2,2-diethylhexanoic acid, pivalic acid, 2,2-dimethylpropionic acid, trimethylacetic acid, neopentanoic acid, 2-ethylhexanoic acid, isononanoic acid, 3,5,5-trimethylhexanoic acid, isopalmitic acid, isostearic acid, 16-methylheptadecanoic acid and 12,15-dimethylhexadecanoic acid. The non-cyclic aliphatic monocarboxylic acids are preferably selected from liquid non-cyclic C 10 -C24 Monocarboxylic acid or liquid branched chain C 10 -C 24 It should be understood that many non-cyclic C 10 -C 24 The monocarboxylic acids may originate from natural sources, in which case, in isolated form, they are generally present as mixtures of acids of different chain lengths with different degrees of branching.

[0144] Preferably, the monocarboxylic acid is a non-cyclic C 10 -C 24 Monocarboxylic acid, C6-C 20 Cyclic monocarboxylic acids or mixtures thereof.

[0145] additive

[0146] The antifouling coating composition of the present invention optionally comprises one or more additives.Examples of additives that may be present in the coating composition of the present invention include rheology modifiers, defoamers, pH adjusters, dispersants, wetting agents, coalescing agents and plasticizers.

[0147] The coating composition of the present invention preferably comprises a rheology modifier. Mixtures of two or more rheology modifiers may be used. The presence of a rheology modifier in the composition of the present invention advantageously improves storage stability, the bulk of the coating composition, and the application characteristics of the coating.

[0148] Examples of suitable rheology modifiers are polysaccharide rheology modifiers, associative rheology modifiers, clays, cellulosic rheology modifiers, fumed silica or mixtures thereof.

[0149] Exemplary polysaccharide rheology modifiers for use in the coating composition include fucoidan, guar gum, locust bean gum, and xanthan gum.

[0150] Exemplary clay rheology modifiers for use in the coating composition of the present invention include kaolin, montmorillonite clay, illite clay, chlorite clay, synthetic clay or organically modified clay.Preferred clay rheology modifiers are synthetic clays or organically modified clays.

[0151] Exemplary associative rheology modifiers for use in the coating composition include nonionic synthetic associative rheology modifiers (niSAT), hydrophobically modified alkoxylated urethanes such as hydrophobically modified ethoxylated urethanes (HEUR), hydrophobically modified alkali swellable emulsions (HASE), and styrene-maleic anhydride terpolymers (SMAT). Acidic acrylate copolymers of ethyl acrylate and methacrylic acid (crosslinked), and acrylic terpolymers of ethyl acrylate, methacrylic acid, and nonionic urethane surfactant monomers (crosslinked) may also be used as associative rheology modifiers. A particularly preferred associative rheology modifier present in the coating composition of the present invention is a hydrophobically modified ethoxylated urethane (HEUR).

[0152] Preferably, the rheology modifier is present in the composition of the present invention in an amount of 0-10 wt%, more preferably 0.1-6 wt% and still more preferably 0.1-2.0 wt%, based on the total dry weight of the composition.

[0153] The coating composition of the present invention may include a defoamer. Defoamers are sometimes also referred to as foam control agents or defoamers. A wide range of defoamers are commercially available and can be used in the coating composition of the present invention. Representative examples of suitable defoamers include organosiloxanes, polyethers, polyether-modified silicones, mineral oils, and combinations thereof. Preferred coating compositions of the present invention include 0-2.0 wt% of a defoamer based on the total weight of the coating composition.

[0154] The coating composition of the present invention may contain a pH adjuster such as ammonia, 2-aminopropanol, sodium hydroxide (NaOH), sodium carbonate (Na2CO3) and sodium bicarbonate (NaHCO3).

[0155] Coagulants can be optionally included. In waterborne coating compositions, the wet product used is inhomogeneous, which is contrary to the uniform solvent composition when used. In order to form a film, polymer binder droplets or particles must coalesce. Coagulants help this process in the aqueous phase. The example of suitable coalescing agents is ester alcohol, benzyl alcohol, propylene glycol monomethyl ether (PM), propylene glycol propyl ether (PnP), dipropylene glycol n-butyl ether (DPnB), propylene glycol phenyl ether (PPh), tripropylene glycol n-butyl ether (TPnB), ethylene glycol propyl ether (EP), ethylene glycol butyl ether (EB), diacetone alcohol (DAA) and dipropylene glycol methyl ether (DPM).

[0156] In order to improve or promote the dispersion of pigments, fillers and biocides, it may be desirable to incorporate a wetting / dispersing additive that is compatible with the aqueous coating composition. A wide range of dispersants are commercially available and can be used in the coating composition of the present invention. Suitable dispersants include conventional anionic, cationic, nonionic and amphoteric dispersants and combinations thereof.

[0157] Examples of suitable dispersants are polyalkylene glycols, polyacrylamides, polyether carboxylates, polycarboxylates and sodium salts of acrylic acid polymers.

[0158] Plasticizers may be added to the coating composition of the present invention. Examples of suitable plasticizers are silicone oils (non-reactive polydimethylsiloxanes), chlorinated paraffins, phthalates, phosphates, sulfonamides, adipates, epoxidized vegetable oils and sucrose acetate isobutyrate.

[0159] Solvents

[0160] The antifouling coating composition of the present invention is an aqueous composition, ie, an aqueous composition comprising water as a main solvent.

[0161] The antifouling coating composition of the present invention preferably contains water as a main solvent.

[0162] Small amounts of organic co-solvents such as ketones, alcohols, glycol ethers or other oxygenated solvents that are soluble or miscible in water may be present.

[0163] Preferably, the coating composition comprises less than 10 wt% of organic solvent, further preferably less than 5 wt% of organic solvent, relative to the total weight of the composition as a whole.

[0164] The coating composition comprises at least 5 wt% water relative to the total weight of the composition as a whole. Preferably, the coating composition comprises at least 10 wt% water relative to the total weight of the composition as a whole. Preferably, the composition comprises 5 to 60 wt%, more preferably 10 to 50 wt%, for example 15 to 40 wt% water relative to the total weight of the composition as a whole.

[0165] Biocides

[0166] The antifouling coating composition of the present invention preferably further comprises a compound capable of preventing the fixation or growth of marine fouling on surfaces. The terms antifouling agent, antifouling agent, biocide, active compound, poison are used in the industry to describe known compounds that act to prevent marine fouling on surfaces. The antifouling agent of the present invention is a marine antifouling agent.

[0167] The antifouling agent may be inorganic, organometallic or organic. Suitable antifouling agents are commercially available.

[0168] Examples of inorganic antifouling agents include copper and copper compounds, such as copper oxides, such as cuprous oxide and cupric oxide, copper thiocyanate and copper sulfide, copper powder and copper flakes.

[0169] Examples of organometallic marine antifouling agents include zinc pyrithione, copper pyrithione, zinc bis(dimethyldithiocarbamate) [ziram], and zinc ethylenebis(dithiocarbamate) [mancozeb].

[0170] Examples of organic marine antifouling agents include heterocyclic compounds such as 2-(tert-butylamino)-4-(cyclopropylamino)-6-(methylthio)-1,3,5-triazine [cybutryne], 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one [DCOIT], 1,2-benzisothiazolin-3-one, 3-(3,4-dichlorophenyl)-1,1-dimethylurea [diuron], N-dichlorofluoromethylthio-N',N'-dimethyl-N-phenylsulfonamide [difluanid], N-dichlorofluoromethylthio-N',N'-dimethyl-N-phenylsulfonamide [difluanid], Dimethyl-N-toluenesulfonamide [tolylfluanid], N-(2,4,6-trichlorophenyl)maleimide, triphenylboranepyridine [TPBP], 3-iodo-2-propynyl N-butylcarbamate [IPBC], 2,4,5,6-tetrachloroisophthalonitrile [chlorothalonil], p-((diiodomethyl)sulfonyl)toluene, 4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile [trolopride], 4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole [medetomidine].

[0171] Other examples of marine antifouling agents may be tetraalkylphosphonium halides, quaternary ammonium salts, guanidine derivatives such as dodecylguanidine monohydrochloride; macrolides, including avermectins and derivatives thereof such as ivermectin; spinosads and derivatives such as spinosad; capsaicin and derivatives such as phenylcapsaicin; and enzymes such as oxidases, proteolytic enzymes, hemicellulose hydrolytic enzymes, cellulose hydrolytic enzymes, lipolytic enzymes, and starch hydrolytic enzymes. Complexes such as di(ethyl-4,4,4-trifluoroacetoacetic acid copper (Cu(ETFAA)2 described in EP 3860349 and WO2021113564 can also be used in antifouling formulations.

[0172] Copper-based antifouling coating compositions contain inorganic copper biocides, such as metallic copper, cuprous oxide, copper thiocyanate, etc., to prevent hard scale.

[0173] The cuprous oxide material has a typical particle size distribution of 0.1 to 70 μm and an average particle size (d50) of 1 to 25 μm. The cuprous oxide material may contain a stabilizer to prevent surface oxidation and agglomeration. Examples of commercially available cuprous oxide paint grades include Nordox copper oxide red paint grades and Nordox XLT from Nordox AS, copper oxide orange, Furukawa cuprous oxide from Furukawa Chemicals Co., Ltd.; Red Copp 97, Purple Copp 97, LoLo Tint LM, LoLo Tint NP, LoLo Tint LM B / B from American Chemet Corporation; Red cuprous oxide from Cosaco (Cuprous Oxide Red); Cuprous oxide roasted from Taixing Smelting Plant Co., Ltd., Cuprous oxide electrolytic.

[0174] Another example of a commercially available grade of inorganic copper is cuprous thiocyanate, for example from Bardyke Chemicals Ltd.

[0175] The copper pyrithione material (needle-shaped powder) has a typical average particle size (d50) of 2 to 7 μm and may contain a surfactant for stabilization. Examples of commercially available materials are Omedin copper from Arxada (Arch Chemicals BV); CleanBio from Kolon Life Science.

[0176] Some suitable antifouling agents are sold under the trade names Econea (tralopilide from Janssen and Kolon LifeScience); Selektope (metoprimidine from I-Tech); SeaNine 211N (DCOIT from DuPont Microbial Control); SeaNine Ultra (encapsulated DCOIT from DuPont Microbial Control); UmiGard Pro and UmiGard SynPro (from Arxada), Perozine Marine (mancozeb from Agria S.A.); Zineb Nautec (mancozeb from United Phosphorus).

[0177] Antifouling coating compositions that do not contain inorganic copper biocides typically use a range of organic biocides such as 4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole [medetomidine] and 4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile [trolopride] to prevent hard fouling. Any known biocide may be used in the present invention.

[0178] Preferred biocides are cuprous oxide, copper thiocyanate, zinc pyrithione, copper pyrithione, zinc ethylenebis(dithiocarbamate) [mancozeb], 2-(tert-butylamino)-4-(cyclopropylamino)-6-(methylthio)-1,3,5-triazine [cybutryne], 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one [DCOIT], N-dichlorofluoromethylthio-N',N'- Dimethyl-N-phenylsulfonamide [fungifendil], N-dichlorofluoromethylthio-N',N'-dimethyl-N-toluenesulfonamide [fungifendil], triphenylboranepyridine [TPBP] and 4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile [trolopride], 4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole [medetomidine] and phenylcapsaicin.

[0179] As is known in the art, mixtures of biocides may be used, since different biocides act against different marine fouling organisms. Mixtures of antifouling agents are generally preferred.

[0180] In one embodiment, the antifouling coating composition comprises cuprous oxide and / or cupric thiocyanate and one or more agents selected from copper pyrithione, mancozeb, 4,5-dichloro-2-octyl-4-isothiazolin-3-one, trolopride and medetomidine.

[0181] In an alternative embodiment, the antifouling coating does not contain an inorganic copper biocide. In this embodiment, a preferred biocide combination includes a combination of trolopride and one or more selected from zinc pyrithione, copper pyrithione, mancozeb, 4,5-dichloro-2-octyl-4-isothiazolin-3-one and medetomidine.

[0182] When present, the total amount of biocide may be up to 60 wt % of the coating composition, such as 0.1 to 50 wt %, for example 5 to 45 wt %, relative to the total weight of the coating composition. When an inorganic copper compound is present, a suitable amount of biocide may be 5 to 60 wt % relative to the total weight of the coating composition. When an inorganic copper compound is avoided, lower amounts may be used, such as 0.1 to 25 wt %, for example 0.2 to 10 wt %, relative to the total weight of the coating composition.

[0183] When present, the total amount of biocide may comprise up to 70 wt % of the coating composition, such as 0.1-60 wt %, for example 10-60 wt %, relative to the total dry weight of the coating composition.

[0184] It should be understood that the amount of biocide may vary depending upon the end use and the biocide used.

[0185] Some biocides can be encapsulated or adsorbed on an inert carrier or bonded to other materials for controlled release. Some biocides can be surface treated to improve stability, dispersibility and / or controlled release. These percentages refer to the amount of active biocide present and therefore do not refer to any carrier used.

[0186] Pigments, Extenders and Fillers

[0187] In addition to the polymer binder, rosin ester, biocide (including cuprous oxide) and any of the above optional components, the antifouling coating composition according to the present invention may optionally further comprise one or more components selected from inorganic or organic pigments, extenders and fillers.

[0188] The pigment may be an inorganic pigment, an organic pigment or a mixture thereof. Preferably, the inorganic pigment is an inorganic pigment. Examples of inorganic pigments include titanium dioxide, red iron oxide, yellow iron oxide, black iron oxide, zinc oxide, zinc sulfide, lithopone and graphite. Examples of organic pigments include carbon black, phthalocyanine blue, phthalocyanine green, naphthol red and diketopyrrolopyrrole red. The pigment may optionally be surface treated to more easily disperse in the paint composition. The titanium dioxide may be surface treated with silicone, zinc, zirconium or aluminum.

[0189] Examples of extenders and fillers are minerals such as dolomite, calcite, quartz, barite, magnesite, aragonite, silica, nepheline syenite, wollastonite, talc, chlorite, mica, kaolin, pyrophyllite, perlite, silica and feldspar; synthetic inorganic compounds such as calcium carbonate, magnesium carbonate, barium sulfate, calcium silicate, zinc phosphate and silicon dioxide (colloidal, precipitated, fumed, etc.); polymeric and inorganic microspheres, such as uncoated or coated hollow and solid glass beads, uncoated or coated hollow and solid ceramic beads, porous and dense beads of polymeric materials.

[0190] Preferably, the total amount of extenders, fillers and / or pigments present in the composition of the present invention is 2-60 wt%, more preferably 5-50 wt%, still more preferably 7-45 wt%, based on the total weight of the composition.

[0191] Preferably, the total amount of extenders, fillers and / or pigments present in the composition of the present invention is 2-80 wt.%, preferably 5-70 wt.%, more preferably 10-65 wt.%, based on the total dry weight of the coating composition.

[0192] It will be appreciated by those skilled in the art that extender, filler and pigment levels will vary depending upon the particle size distribution, particle shape, surface morphology, particle surface-resin affinity, the presence of other components and the end use of the coating composition.

[0193] Examples of reinforcing fillers are flakes and fibers. Fibers include natural and synthetic inorganic fibers and natural and synthetic organic fibers, as disclosed in WO 00 / 77102. Representative examples of fibers include mineral-glass fibers, wollastonite fibers, montmorillonite fibers, snow silica montmorillonite fibers, atapulgite fibers, calcined bauxite fibers, volcanic rock fibers, bauxite fibers, rock wool fibers, and processed mineral fibers from mineral wool. Preferably, the fibers have an average length of 25 to 2,000 μm and an average thickness of 1 to 50 μm, wherein the ratio between the average length and the average thickness is at least 5. Preferably, based on the total weight of the composition, the reinforcing filler is present in the composition of the present invention in an amount of 0-20wt%, more preferably 0.5-15wt% and still more preferably 1-10wt%.

[0194] Examples of plate-like fillers are mica, glass flakes and micronized iron oxide (MiO).

[0195] The antifouling coating composition of the present invention may preferably have a solid content higher than 35 vol%, such as higher than 40 vol%, such as higher than 42 vol%.

[0196] More preferably, the antifouling coating composition may have a volatile organic compound (VOC) content of less than 200 g / L, preferably less than 150 g / L, more preferably less than 100 g / L, for example less than 70 g / L. The VOC content may be calculated as described in, for example, ASTM D5201-01 or IED 2010 / 75 / EU or measured as described in, for example, US EPA method 24 or ISO 11890-2.

[0197] The antifouling coating composition of the present invention desirably has a pigment volume concentration (PVC) of less than 80%, more preferably less than 60%, further preferably less than 55%. Pigment volume concentration (PVC) is defined as the ratio of pigment volume to total dry film volume.

[0198] application

[0199] The antifouling coating composition of the present invention can be applied to all or part of any surface of an object that is subject to fouling. The surface can be permanently or intermittently underwater (e.g., by tidal motion, different cargo loading or expansion). The surface of the object will typically be the hull of a ship or the surface of a fixed marine object (such as an oil platform or buoy). The surface of the substrate can be a "natural" surface (e.g., a steel surface) or a surface that already has an organic primer layer coated thereon.

[0200] The application of the coating composition can be accomplished by any convenient means, such as by painting (e.g., with a brush or roller) or spraying the coating onto the object. Typically, the surface needs to be separated from the seawater to allow coating. Application of the coating can be accomplished as is conventionally known in the art.

[0201] When antifouling coating is applied to an object (e.g., a ship hull), the surface of the object is preferably not only protected by a single coating of the antifouling coating composition. Depending on the nature of the surface, the antifouling coating can be directly applied to an existing coating system. This coating system can include paints of multiple layers of different general types (e.g., epoxy resins, polyesters, vinyl or acrylic acid or mixtures thereof). Starting from an uncoated surface (e.g., steel, aluminum, plastics, composite materials, fiberglass or carbon fiber), a complete coating system will generally include one or two layers of primer such as an anticorrosive coating (e.g., a curable epoxy coating or a curable modified epoxy coating), a layer of bonding layer (tie-coat) (e.g., a curable modified epoxy coating or a physically dried vinyl coating) and one or two layers of antifouling paint. In exceptional cases, further antifouling paint layers can be applied. If the surface is a clean and complete antifouling coating from a previous application, new antifouling paint can be directly applied, typically one or two coatings, with more coatings in exceptional cases. When two or more coatings of the antifouling coating composition are applied, different coatings can be antifouling coatings of different compositions. If different compositions are used in successive layers, the difference may be, for example, the type of biocide or the level of biocide.

[0202] The coating composition of the present invention can be applied to anticorrosive primers, bonding coatings and antifouling coating films prepared from water-based, solvent-based and solvent-free coating compositions, preferably applied to epoxy primer layers.

[0203] The invention will now be defined with reference to the following non-limiting examples.

[0204] Example

[0205] Materials and methods

[0206] Table 1: Materials List

[0207]

[0208]

[0209] The average particle size (d50) and the maximum particle size (topcut) were measured with a Malvern Mastersizer according to ISO 13320: 2009. The surface area, BET, was measured according to ISO 5794-1.

[0210] Table 2: Overview of polymer dispersions

[0211]

[0212] 1 Polymer dispersions D-5 and D6: were synthesized and prepared as described below.

[0213] Table 3: Overview of rosin esters

[0214] R-1 R-2 R-3 Appearance (20℃) Viscous liquid Viscous liquid solid Viscosity(cP) 3150 41300 - Acid value (mg KOH / g) 5-10 12-15 14-16 Softening point(℃) NA NA 84 Tg(℃) -37 -28 42

[0215] Rosin ester R-1: methyl ester of rosin (Granolite M from DRT); Rosin ester R-2: triethylene glycol (TEG) ester of rosin (Granolite TEG from DRT); Rosin ester R-3: glycerol ester of rosin (Granolite SG from DRT)

[0216] Table 4: Rosin acid and rosin ester dispersants 1 Overview

[0217]

[0218]

[0219] 1 Amounts of raw materials in parts by weight.

[0220] 2 E-1: rosin acid dispersion (Dermulsene A7510 from DRT, softening point 75° C., viscosity 600 mPa·s at 20° C., pH 7.8 at 20° C.).

[0221] VOC calculation

[0222] The calculated VOC (in g / L) given as Mat.VOC (VOC of material, actual VOC, based on the total coating formulation) is shown in Table 10

[0223] Table. Calculations for regulatory VOC and material VOC (water-less and water-free) The VOC can be calculated by standard ASTM D5201-05a.

[0224] Determination of glass transition temperature of rosin ester

[0225] The glass transition temperature (Tg) was obtained by differential scanning calorimetry (DSC) measurement. DSC measurements were performed on Instruments DSCQ200. The measurements were performed by running a heating-cooling-heating program at a heating rate of 10°C / min and a cooling rate of 10°C / min in a temperature range from -80°C to 150°C and using an empty pan as a reference. The data were processed using the Universal Analysis software from TA Instruments. As defined in ASTM E1356-08, the inflection point of the glass transition range of the second heating is reported as the Tg of the polymer. About 10 mg of material was transferred to an aluminum pan. The pan was sealed with a non-airtight lid.

[0226] Determination of glass transition temperature of (meth)acrylic adhesives

[0227] The glass transition temperature (Tg) was obtained by differential scanning calorimetry (DSC) measurement. DSC measurements were performed on TA Instruments DSC Q200. The measurements were performed by running a heating-cooling-heating program at a heating rate of 10°C / min and a cooling rate of 10°C / min in a temperature range from -80°C to 150°C or -50°C to 150°C and using an empty pan as a reference. The data were processed using the Universal Analysis software from TA Instruments. As defined in ASTM E1356-08, the inflection point of the glass transition range of the second heating is reported as the Tg of the polymer. The polymer dispersion film was coated on a glass plate using a frame coater with a gap size of 100 μm and allowed to dry at least 24 hours at 23°C to prepare the sample. About 10 mg of the dried polymer material was transferred to an open aluminum pan.

[0228] Determination of Viscosity of Rosin Ester

[0229] The viscosity of liquid rosin esters was determined using a Brookfield DV-IPrime digital viscometer at a rotation speed of 12 rpm and using a LV-4 spindle according to ASTM D2196 Test Method A. The samples were tempered to 23.0°C ± 0.5°C prior to measurement.

[0230] Particle size measurement

[0231] The average particle size was determined by dynamic light scattering (DLS) using a Malvern Zetasizer Nano S particle size analyzer at a wavelength of 633 nm and a constant angle of 173 °. The measurements were performed at 25 ° C. Before the measurements, 0.1 mL of sample was diluted with 0.1 L of deionized water. The measurement duration, measurement position, and attenuator were automatically set by the instrument software. Each sample was measured 3 times, and the results were reported as the average value of the Z average particle size.

[0232] Preparation of (meth)acrylic acid dispersion

[0233] (Meth)acrylic dispersions D-1 to D-4 are commercially available, whereas (meth)acrylic dispersions D-5 and D-6 were prepared according to the described procedure.

[0234] In a reaction vessel equipped with an agitator, condenser and nitrogen inlet, monomer feed and initiator feed, the surfactant solution was heated to 70°C under nitrogen. Monomer Feed 1 and Initiator Solution 1 were added. The mixture was then stirred for 30 minutes while maintaining the temperature at 70°C. The temperature was then raised to 80°C. While stirring at 80°C, Monomer Feed 2 and Initiator Solution 2 were slowly added to the vessel at a constant rate over 3 hours. When the addition was complete, the mixture was stirred at 80°C for 2 hours, and the final polymer dispersion was then cooled and filtered through a 100 μm nylon filter bag to remove larger particles.

[0235] Table 5: Preparation of (meth)acrylic acid dispersions in parts by weight

[0236]

[0237] Preparation of rosin and rosin ester dispersions

[0238] Dispersion E-1 was obtained commercially.

[0239] Dispersions E-2 and E-3 were prepared according to the following procedure. A solution of water and additives was heated to 75°C in a beaker. Rosin ester heated to 75°C was slowly added under stirring using an Ultra Turrax rotor-stator mixer. The mixture was then dispersed at 25000 rpm for 2 minutes.

[0240] Dispersion E-4 was prepared according to the following procedure. A solution of water and additives was heated to 75° C. in a beaker. Rosin ester dissolved in xylene was heated to 75° C. The rosin ester solution was slowly added to the aqueous solution under stirring using an Ultra Turrax rotor-stator mixer. The mixture was then dispersed at 25 000 rpm for 2 minutes. Xylene and water were then partially removed using a rotary evaporator.

[0241] Coating preparation

[0242] Pigments, extenders and fillers, biocides, additives and water are mixed and ground under high shear using a dissolver with impeller blades until the mill base has a fineness of grind below 40 μm. The stirring rate is then reduced and the binder ingredients are slowly added. More additives are added later when / if necessary.

[0243] Mechanical properties testing

[0244] Accelerated cracking test of coating films

[0245] PVC panels were coated with Safeguard Plus (a two-component polyamide-cured vinyl epoxy coating manufactured by Chokwang Jotun Ltd., South Korea) using airless spray. In Example 25, the PVC panels were also coated with Jotacoat Universal N10 (a two-component polyamine-cured epoxy coating from Jotun AS). The antifouling coating was applied to the panels using a film coater with a gap size of 800 μm. The panels were dried at 52° C. for 72 h and then immersed in seawater at 40° C. At regular intervals, the panels were taken out and dried at ambient conditions for 24 hours and at 52° C. for 24 hours before evaluation. The cracking of the panels was evaluated visually and at 10x magnification, and was rated as described in ISO 4628-4:2005. The panels were then re-immersed.

[0246] After evaluation on the ratings given in Table 6, the ratings after drying at 52°C are reported in Tables 7 to 10. The values ​​of "size" and "amount" of defects are multiplied and given as integer values, e.g. a crack with size 3 and amount 3 is given as 9.

[0247] Table 6: Evaluation of cracking or blistering after immersion testing in salt water and fresh water, respectively.

[0248] grade Evaluate 0 Excellent 1-5 good 6-10 medium 11-15 Difference 16-25 Very bad

[0249] A rating of 0-5 (excellent-good) was considered acceptable.

[0250] Accelerated Blistering Test of Coating Films

[0251] A procedure similar to the cracking test was performed, except that the panels were immersed in fresh water at 30°C for the blister test. The panels were evaluated for blistering visually and at 10x magnification and rated as described in ISO 4628-2:2016. Following the rating evaluation given in Table 6, the ratings after fresh water immersion are reported in Tables 7 to 10. The values ​​of "Size" and "Number" of defects are multiplied and given as an integer value, e.g. a blister with size 3 and number 3 is given as 9.

[0252] Determination of polishing rate of antifouling coating films on rotating disks in seawater

[0253] The polishing rate is determined by measuring the reduction of the film thickness of the coating film over time. For this test, a PVC disc is used. The coating composition is applied as a radial strip on the PVC disc using a film applicator with a gap size of 300 μm. The thickness of the dry coating film is measured by an optical surface profiler (TaiCaan laser profiler). The PVC disc is mounted on an axis and rotated in a container where seawater flows. The speed of the rotating axis gives the average simulated speed of 16 sections on the disc. Natural seawater that has been filtered and temperature adjusted to 25°C ± 2°C is used. The PVC disc is taken out at regular intervals to measure the film thickness. Before measuring the film thickness, the disc is rinsed and allowed to dry overnight at room temperature.

[0254] After 28 weeks, the ideal polish is 10-60μm.

[0255] Table 7: Paint Examples 1-15 with Dispersion D-1

[0256]

[0257] Table 8: Comparative Example using Dispersion D-1

[0258]

[0259] Table 9: Paint Examples with Dispersions D-2 to D-6

[0260]

[0261] Table 10: Comparative paint examples with dispersions D-2 to D-6

[0262]

[0263] Table 11: Tests of different primers

[0264]

[0265]

[0266] Observations from experiments using (meth)acrylic dispersion D-1 (Tg 17.9°C), Table 7 (Examples) and Table 8 (Comparative Examples)

[0267] - Examples 1 and 2, using binder D-1 and rosin methyl ester in different amounts. The polishing results show that the polishing increases with increasing amount of rosin methyl ester. No cracking or blistering was observed.

[0268] - Comparative Example 1 is directly comparable to Examples 1 and 2 and shows that in the absence of rosin methyl ester, the polish is lower (<10 μm).

[0269] - Examples 3 and 4, using binder D-1 and resin TEG ester in different amounts. The results show that polishing increases with increasing amounts of rosin TEG ester. No cracking was observed after salt water immersion. Fresh water immersion was not tested.

[0270] - Comparative Examples 2 and 3, using D-1 as binder and using rosin acid instead of rosin ester. The results showed good polishing, but high cracking and blistering in the film after immersion in salt and fresh water.

[0271] - Comparison of Examples 4 and 5 using D-1 and a solid glycerol ester of rosin with Tg < 0 in different amounts. The results show that there is little or no polishing when a rosin ester that is solid at room temperature (Tg < 0) is used. No cracking or blistering is observed.

[0272] - Example 5 shows that it is possible to use a mixture of binder D-1 and rosin methyl ester and rosin acid. The polishing rate is high and there is no cracking or blistering. The ratio of rosin ester:rosin acid is 1:1.5.

[0273] - Example 6, using binder D-1 and a 1:1 ratio of rosin ester to rosin acid. Polishability was good and there was no cracking or blistering.

[0274] - Example 7, using binder D-1 and lower amounts of rosin methyl ester, the ratio of D-1 : rosin methyl ester is 9: 1. Polishing is still good and there is no cracking or blistering.

[0275] - Comparative Example 8 shows that 0.05 wt% of rosin methyl ester and a ratio of D-1 to rosin methyl ester of 95:5 are not sufficient amounts of rosin methyl ester to obtain a good polish.

[0276] - Example 8, D-1 was used as binder and rosin methyl ester and rosin acid were used in a ratio of 1:0.5. Good polishing was observed with no cracking or blistering.

[0277] - Example 9, D-1 was used as binder and rosin TEG ester and rosin acid were used in a ratio of 1:2:1. Good polishing was observed with no cracking or blistering.

[0278] - Examples 10 and 11, different amounts of D-1 and rosin methyl ester were used in a formulation with another cuprous oxide grade (LoLoTint) and copper pyrithione as biocide. The results show good polishing and no cracking or blistering. Comparative Examples 6 and 7 are directly comparable to Examples 10 and 11. Comparative Example 6, only (meth)acrylic dispersion D-1 without rosin ester or rosin acid, shows low polishing with no cracking or blistering. Comparative Example 7 includes rosin acid and the results show good polishing but blistering after fresh water immersion.

[0279] - Examples 12 and 13, different amounts of D-1 and rosin methyl ester were used in copper-free formulations, zinc pyrithione and troclopidogrel were used as biocides. The results showed good polishing and no cracking and foaming after immersion in salt and fresh water.

[0280] - Examples 14 and 15, different amounts of D-1 and rosin methyl ester were used in combination with copper pyrithione and trolopride as biocides. The results showed good polishing and no cracking and blistering after immersion in salt and fresh water.

[0281] Observations from experiments using (meth)acrylic dispersions D-2 to D-6, Table 9 (Examples) and Table 10 (Comparative Examples).

[0282] - Examples 16 and 17, (meth)acrylic dispersion D-2 (Tg 1.7°C) was used in combination with different amounts of rosin methyl ester. The polishing rate was good and no cracking or blistering was observed. These results show that (meth)acrylic adhesives with lower Tg can also be used.

[0283] - Example 18, using (meth)acrylic dispersion D-2 as binder and a mixture of rosin methyl ester and rosin acid in a ratio of 1:2.5. Polishes well with no cracking or blistering.

[0284] - Comparative Example 9, using (meth)acrylic dispersion D-2 and a rather high amount of abietic acid. The polishing rate was higher, but a lot of cracking and blistering was also observed.

[0285] - Examples 19 and 20, using (meth)acrylic dispersion D-3 (Tg 38.4°C) with a higher Tg than adhesive D-1. Different amounts of rosin methyl ester were used. Polishing was good, no cracking after salt water immersion, and low blistering after fresh water immersion. These results show that (meth)acrylic adhesives with higher Tg can also be used.

[0286] - Comparative Examples 10 and 11, (meth)acrylic dispersion D-3 was used in combination with rosin acid or alone. In the presence of rosin acid, polishing was good, while cracking and blistering were observed after seawater and freshwater immersion, respectively. Use of D-3 alone, without rosin acid, showed no cracking or blistering after saltwater and freshwater immersion, but polishing was lower.

[0287] - Example 21, using D-3 and a mixture of rosin methyl ester and rosin acid in a ratio of 1:1.5. The results showed good polishing after salt water immersion, low cracking and no blistering after fresh water immersion.

[0288] - Example 22, (meth)acrylic dispersion D-4 (18.5°C) was used with a combination of rosin methyl ester and rosin acid at a ratio of 1:1.5. After immersion in salt water and fresh water, respectively, the polishing rate was appropriate, and the degree of cracking and foaming was low.

[0289] - Comparing Examples 12 and 13, D-4 was used alone or in combination with rosin acid. In the absence of rosin acid or rosin esters, there was no polishing, while the mechanical properties were good. When D-4 was used with rosin acid, polishing increased slightly, but was still low. Poor mechanical properties, high cracking and blistering were observed.

[0290] - Example 23, (meth)acrylic dispersion D-5 (Tg - 33°C) (having the lowest Tg of the (meth)acrylic dispersions) was used together with rosin methyl ester. The results showed adequate polishing and neither cracking nor blistering.

[0291] - Comparative Example 14 shows that (meth)acrylic dispersion D-5 does not produce sufficient polish without the addition of rosin methyl ester. However, the mechanical properties are good and no cracking or blistering is observed.

[0292] - Example 24, (meth)acrylic dispersion D-6 (Tg -18.3°C) was used together with rosin methyl ester. Example 24 showed adequate polishing and good mechanical properties, with no cracking or blistering observed.

[0293] - Comparative Example 15, using D-6 without rosin ester or acid. Cracking was observed after exposure to salt or fresh water. Polishing rate was inadequate.

[0294] Observations from testing different primers

[0295] - The testing in Example 25 shows that the coating composition of the present invention can be applied over different primers while still maintaining good performance.

Claims

1. A water-based antifouling coating composition comprising: (a) a polymer binder comprising structural units derived from ethylenically unsaturated monomers; and (b) at least 1.0 wt% of a rosin ester, based on the dry weight of the total coating composition, wherein the rosin ester has a glass transition temperature (Tg) of less than 0°C; in, The coating composition comprises at least 5 wt% of water, relative to the total weight of the composition as a whole.

2. The aqueous antifouling coating composition according to claim 1, wherein the composition has a volatile organic compound (VOC) content of less than 200 g / L, preferably less than 150 g / L, more preferably less than 100 g / L, even more preferably less than 70 g / L.

3. The aqueous antifouling coating composition according to claim 1 or 2, wherein: The composition has a pigment volume concentration (PVC) of less than 80%.

4. The aqueous antifouling coating composition according to any one of claims 1 to 3, wherein The polymer binder is in the form of a dispersion.

5. The aqueous antifouling coating composition according to any one of claims 1 to 4, wherein The polymer binder comprises a monomer selected from the group consisting of (meth)acrylic acid, (meth)acrylates, (meth)acrylamide, vinyl chloride, vinyl propionate, maleic acid, itaconic acid, styrene, α-methylstyrene, alkyl vinyl ethers, vinyl pyrrolidone, N-vinylcaprolactam, N-methyl-N-vinylacetamide or (meth)acrylonitrile.

6. The aqueous antifouling coating composition according to any one of claims 1 to 5, wherein The polymer binder comprises (meth)acrylic acid and / or (meth)acrylate monomers, preferably wherein the polymer binder comprises at least 15 wt% (meth)acrylic acid and / or (meth)acrylate monomers relative to the total weight of the polymer binder.

7. The aqueous antifouling coating composition according to any one of claims 1 to 6, wherein The polymer binder comprises residues of at least one, and preferably at least two, monomers of formula (I): Where R 1 is H or CH3; R 2 is H or an optionally linear, branched or cyclic substituted C 1-18 Alkyl, wherein the substituent is selected from OH, OR 3 and N(R 4 )2; R 3 Selected from C 1-8 Alkyl and C 3-8 cycloalkyl; and Each R 4 Independently selected from H, C 1-8 Alkyl and C 3-8 Cycloalkyl.

8. The aqueous antifouling coating composition according to any one of claims 1 to 7, wherein The composition further comprises abietic acid and / or abietic acid derivatives.

9. The aqueous antifouling coating composition according to any one of claims 1 to 8, wherein The composition further comprises one or more biocides.

10. The aqueous antifouling coating composition according to any one of claims 1 to 9, wherein The composition comprises 1.0 to 40 wt % of the polymer binder, based on the total dry weight of the composition.

11. The aqueous antifouling coating composition according to any one of claims 1 to 10, wherein The composition comprises 1.0 to 30 wt % of the rosin ester based on the dry weight of the total composition.

12. A method for applying an aqueous antifouling coating composition to a substrate, comprising applying, for example by spraying, the aqueous antifouling coating composition of any one of claims 1 to 11 to a substrate and drying the coating composition.

13. A method for protecting an object from contamination, the method comprising coating at least a portion of the object subject to contamination with the antifouling coating composition according to any one of claims 1 to 11.

14. A substrate coated with the aqueous antifouling coating composition according to any one of claims 1 to 11, wherein: The coating composition has been dried.

15. A substrate according to claim 14, wherein the substrate is the surface of a marine structure, preferably a surface of a marine structure which is submerged when in use.

16. Use of a rosin ester having a glass transition temperature (Tg) of less than 0°C for increasing the polishing rate of an aqueous antifouling coating composition, preferably an antifouling coating composition comprising a polymer binder comprising structural units derived from ethylenically unsaturated monomers, more preferably an antifouling coating composition comprising a polymer binder comprising (meth)acrylic acid and / or (meth)acrylate monomers.

Images