Post-cure treatment of a fouling control coat

Abstract

The present invention relates to a method of post-cure treatment of a fouling control paint coat, said method comprising the following steps:  a. applying an post-cure treatment composition on the surface of said fouling control paint coat; b. allowing the post-cure treatment composition to stay in contact with the surface of said fouling control paint coat for a period of at least 2 hours; wherein said post-cure treatment composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils. The invention further relates to the use of a post-cure treatment for providing fouling control properties to a fouling control paint coat. The invention further relates to a structure, preferably a marine structure, having on the outer surface a fouling control top coat being subjected to a post-cure treatment. A post-cure treatment composition is also provided.

Description

[0001] Post-cure treatment of a fouling control coat

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to a method of post-cure treatment of a fouling control coat. The invention further relates to the use of a post-cure treatment for providing fouling control properties to a fouling control paint coat. The invention further relates to a structure, preferably a marine structure, having on the outer surface a fouling control top coat being subjected to a post-cure treatment. Also provided is a post-cure treatment composition for a fouling control paint.

[0004] BACKGROUND OF THE INVENTION

[0005] Aquatic structures, in particular immersed marine structures that come in contact with water, especially sea-water, have a tendency to become fouled by marine organisms. Fouling control coatings are abundantly used for such structures, e.g. ships, buoys, watercraft structures, etc. in order to suppress settlement of such marine organisms, or to encourage their release.

[0006] Fouling control coating systems for steel structures such as marine structures typically include three principal layers, namely an anticorrosive layer applied to the steel substrate, a fouling control layer, and an intermediate layer, often referred to as a "tie-coat", for establishing strong bonding between the anticorrosive layer and the fouling control layer. The fouling control layer is often made up of a polysiloxane-based binder matrix.

[0007] Polysiloxane-based coatings are widely used in fouling control coatings for marine structures. A known principle for improving the fouling control effect of a polysiloxane based coat is by inclusion of hydrophilic-modified oils and most often also active ingredients such as biocides or enzymes. For example WO 2011 / 076856 discloses a fouling control coating composition comprising a polysiloxane-based binder system, biocides and hydrophilic-modified silicone oils; WO 2016 / 004961 discloses a fouling control coating composition comprising a polysiloxane-based binder system, biocides and alcohols modified with poly(oxyalkylene).

[0008] These disclosures all describe pre-cure addition of hydrophilic-modified oils to the coating composition, such as poly(oxyalkylene)-modified oils including silicone oils, long-chained alcohols and acrylate oils, i.e. the hydrophilic modified oil has been included in the (wet) coating composition before application on the surface of a substrate.

[0009] The fouling defence properties of the coatings described above depend on the presence of these oils in the coating. The concentration of oil has been observed to decrease over time because of different mechanisms such as degradation, diffusion, leaching, etc. (Camos et al., Progress in Organic Coatings (2017), 112: 101-108). The loss of the hydrophilic oil can lead to fouling and generally it is desired to renew the coating system before it has become completely exhausted from the hydrophilic-modified oil. The traditional way to renew the antifouling performance is by applying an entirely new coating layer or system. Application of a full fouling control coating system, or even only the fouling control layer, is time consuming and costly, and requires large amounts of coating material.

[0010] Addition of a hydrophobic silicone oil post-curing has recently been disclosed by Kolle et al. (Scientific Reports, Nature (2022) 12:11799: On the mechanism of marine fouling-prevention performance of oil-containing silicone elastomers). According to this post-cure method, the coated object and thus the ship hull has to be immersed completely in a (hydrophobic) silicone oil to achieve incorporation of the oil into the coat which is a cumbersome method and requires a large amount of silicone oil. Further, the polysiloxane based coat takes up the silicone oil in an amount of 45-50 wt% of the polydimethylsiloxane coat, causing the coat to swell up to 50% (from 100 pm to 150 pm). This could have a detrimental effect for the mechanical properties of the film or long-term properties.

[0011] Other documents in this technical field include WO2019 / 233985 and CN114761496.

[0012] A simple and cheap method for extending and / or improving the fouling control properties of a fouling control coat would be beneficial.

[0013] SUMMARY OF THE INVENTION

[0014] The present invention provides a method for post-cure treatment of a fouling control paint coat, said method comprising the following steps:

[0015] a. applying a post-cure treatment composition on the surface of said fouling control paint coat; 096

[0016] b. allowing the post-cure treatment composition to stay in contact with the surface of said fouling control paint coat for a period of at least 2 hours;

[0017] wherein said post-cure treatment composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils.

[0018] In one aspect, the invention relates to the use of a method according to the invention for improving the fouling control properties of a fouling control paint coat.

[0019] In one aspect, the invention relates to the use of a post-cure treatment composition in a method according to the invention for improving the fouling control properties of a fouling control paint coat.

[0020] In one aspect, the invention relates to a fouling control paint coat, preferably a non-erodible paint coat that has been treated by the method according to invention.

[0021] In another aspect, the invention relates to a post-cure treatment composition for a fouling control paint, the composition comprising one or more organic solvents, one or more poly(oxyalkylene)-modified silicone oils, and one or more rheological modifiers.

[0022] In another aspect, the invention relates to the use of a post-cure treatment composition for improving the fouling control properties of a fouling control paint coat, wherein the composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils. The organic solvent(s) and poly(oxyalkylene)-modified silicone oils are as defined herein. The post-cure treatment composition may further comprise one or more rheological modifiers as defined herein.

[0023] In another aspect, the invention relates to an article comprising a treated fouling control coating formed by the method as defined herein, wherein the article is a marine structure or part thereof.

[0024] Further details of the invention are set out in the dependent claims and the following description.

[0025] DETAILED DESCRIPTION OF THE INVENTION

[0026] The present invention relates to a method for post-cure treatment of a fouling control paint coat. The terms "fouling control paint coat" and "fouling control coat" are used interchangeably and refer to a coat obtained from a coating composition, which provides a 096

[0027] fouling release surface, where sea organisms cannot stick or are released from the coat when water moves along the surface. The fouling control paint coat is preferably a non-erodible paint coat, more preferably a polysiloxane-based paint coat.

[0028] The inventors have found a simple and effective post-cure treatment for a fouling control paint coat that can enhance and / or prolong the fouling control properties of the coat.

[0029] Unexpectedly, the inventors found that a poly(oxyalkylene)-modified silicone oil (which is hydrophilic or amphiphilic) can be incorporated into a (hydrophobic) fouling control coat by simply applying a composition onto the surface of said fouling control coat.

[0030] In one aspect, the invention therefore simply relates to a method for incorporation of one or more poly(oxyalkylene)-modified silicone oils into a polysiloxane-based paint coat.

[0031] Accordingly, the method comprises the steps of

[0032] a. applying a post-cure treatment composition on the surface of said fouling control paint coat; and

[0033] b. allowing the post-cure treatment composition to stay in contact with the surface of said fouling control paint coat for a period of at least 2 hours;

[0034] wherein said post-cure treatment composition comprises one or more organic solvent(s) and one or more poly(oxyalkylene)-modified silicone oils.

[0035] In one embodiment, the total amount of organic solvent constitutes between 40-99 % by weight of said post-cure treatment composition; and

[0036] the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 1-40 % by weight of said post-cure treatment composition.

[0037] In one embodiment, the total amount of organic solvent constitutes between 40-99 or 40-95, 40-90 , 40-85, or 40-80 or 40-75 or 40-70 % by weight of said post-cure treatment composition, such as between 45-99 or 45-95 or 45-90 or 45-85, or 45-80 or 45-75 or 45-70 %, such as between 50-99 or 50-95 or 50-90 or 50-85, or 50-80 or 50-75 or 50-70 % such as between 55-99 or 55-95 or 55-90 or 55-85, or 55-80 or 55-75 or 55-70 % , such as between 60-99 or 60-95 or 60-90 or 60-85, or 60-80 or 60-75 or 60-70 %, such as between 63-99 or 63-95 or 63-92%, such as between 65-99 or 65-95 or 65-90 or 65-85, or 65-80 or 65-75 or 65-70 %, such as between 70-99 or 70-95 or 70-90 or 70-85, or 70-80 or 70-75 %, such 096

[0038] as between 75-99 or 70-95 or 70-90 or 70-85 or 70-80 %, such as between 80-99 or 80-95 or 80-90 or 80-85 % by weight of said post-cure treatment composition. In a preferred embodiment, the total amount of organic solvent constitutes between 50-90%, more preferably between 50-80%, such as between 50-70% by weight of said post-cure treatment composition.

[0039] In one embodiment, the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 1-40 or 1-35 or 1-30 or 1-25 % by weight, such as between 2-40, or 2-35 or 2-30 or 2-25 % by weight, such as between 5-40, or 1-35 or 5-30 or 5-25 % by weight, such as between 10-40 or 10-35 or 10-30 or 10-25 % by weight, such as between 15-40 or 15-35 or 15-30 or 15-25 % by weight of said post-cure treatment composition. In a preferred embodiment, the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 5-30%, more preferably between 10-30 %, such as between 15-25 % by weight of said post-cure treatment composition.

[0040] Unexpectedly, the inventors discovered that poly(oxyalkylene)-modified silicone oils can be effectively incorporated into a fouling-release coat simply by application of said post-cure treatment composition onto the surface of the coat. The post-cure treatment composition may be applied directly on the surface of the fouling control coat for example by brush or by spray or roller application. The composition may be applied on vertical surfaces such as on the side of a ship hull. It is known from method disclosed by Kolle et al. in Scientific Reports, Nature (2022) 12:11799; that hydrophobic silicone oil can be incorporated into a fouling control coat by immersing the entire coated object (i.e. the ship hull) into the oil for a period. Contrary to the method of the present invention, the method suggested by Kolle et al. is very cumbersome and requires an extensive amount of oil.

[0041] The post-cure treatment of the present invention can be used to prolong the fouling control properties of an aged fouling control coat. This method implies many benefits. For example, replacement of a coat or even simply overcoating a vessel with a fresh fouling control coating normally requires the vessel to stay in dry dock for a longer period. The dry dock time can beneficially be considerably reduced by simply replenishing the poly(oxyalkylene)-modified silicone oil into the aged or worn-out fouling control coat by the method of the invention. The terms "aged coat" and "worn-out coat" refers to a coat that has been applied and used for its purpose for at least a period of time, such as at least 6 months, such as at least one year, such as at least two years etc. For an aged fouling control coat on a marine structure or part thereof, the term "aged" and specifically "worn-out" implies that the coat has been immersed into water for at least that period (i.e. at least 6 months, such as at least one year, such as at least two years etc.). In one embodiment, the aged coat is a fouling control paint coat originally prepared from a fouling control coating composition comprising hydrophilic-modified oils in the wet stage. The post-cure treatment of the present invention is then performed after the hydrophilic modified oils has been partly or fully release from the coat. I.e. the treatment serves as replenishing the coat with hydrophilic modified oil. The method of the invention may also be used to enhance the fouling control properties of a freshly applied coat prepared from a coating composition not already containing any poly(oxyalkylene)-modified silicone oil. I.e. the poly(oxyalkylene)-modified silicone oil is simply incorporated post-curing instead of being included in the coating composition. The term "freshly applied coat" refers to a coat that has not been used for its purpose yet. In one embodiment, the post-cure treatment composition is applied onto the surface of a coat no later than 3 months after application of the coat, such as no later than 2 months from application such as no later than 4 weeks, 3 weeks, 2 weeks or only one week from application of the coat. In a further embodiment, the freshly applied coat is on a marine structure or a part thereof and has not been immersed into water. The freshly applied coat has been allowed to cure before application of the post-cure treatment composition. I.e, the term "freshly applied coat" refers to a coat that has been allowed to cure before application of the post-cure treatment composition. In one embodiment, the freshly applied coat has been allowed to cure for at least 3 hours, such as at least 4 hours, such as at least 5 hours, preferably at least 6 hours, such as at least 8 hours, such as at least 10 hours, such as at least 12 or 16 or 20 or 24 hours before application of the post-cure treatment composition.

[0042] As a further advantage, the post-cure treatment composition of the present invention may be prepared and transported in a concentration that allows the composition to be further diluted with organic solvent on-site before application, which enables a reduction of the amount of material to be transported.

[0043] The post-cure treatment composition may optionally further comprise one or more light stabilizers and / or radical scavengers, such as hindered amine light stabilizers (HALS), and / or one or more UV-absorbers. Although not preferred, the post-cure treatment composition may also comprise one or more biocides.

[0044] The post-cure treatment composition may also comprise additives further described below. The post-cure treatment composition is applied on the surface of a fouling control paint coat. Said fouling control paint coat is preferably a non-erodible paint coat, more preferably a polysiloxane based paint coat prepared from a coating composition comprising a polysiloxane-based binder system. The polysiloxane-based binder system preferably comprises more than 50 wt% of polysiloxanes, such as more than 55 wt%, such as more than 60 wt% or more than 65 wt%, preferably more than 70 wt% such as more than 75 wt% or 80 wt% or or 85 wt % or 90 wt% or 95 wt% of polysiloxanes based on the weight of the total binder system. Fouling control coatings comprising a polysiloxane-based binder system are well-known to the skilled person and has been described in for example WO 2011 / 079856, WO 2013 / 000477 and WO 2014 / 117786.

[0045] The post-cure treatment composition is prepared from a primary composition and a secondary composition. The primary composition comprises the organic solvent, and the secondary composition comprises the one or more poly(oxyalkylene)-modified silicone oils. The composition may optionally include one or more further liquids with suitable properties. The primary and the secondary composition may comprise further constituents such as hindered amine light stabilizers, UV-absorbers and additives as later described.

[0046] In the context of the invention, when reference is made to the "post-cure treatment composition" it refers to the mixed composition ready to be applied on the fouling control coat.

[0047] Organic solvent

[0048] According to the invention, the post-cure treatment composition comprises one or more organic solvent. Organic solvents are divided into two major groups, polar solvent and nonpolar solvent.

[0049] Polar solvents are considered to be solvents with a dielectric constant above 15, and nonpolar solvents are those having a dielectric constant less than 15. Polar solvents may be polar protic or polar aprotic. Examples of polar solvents are alcohols, particularly C2-C10 primary alcohols such as isopropanol, ethanol, butanol, and hexanol.

[0050] Non-polar solvents are C1-C30 straight chain and branched aliphatic hydrocarbons, C3-C20 alicyclic hydrocarbons and aromatic hydrocarbons. Examples of non-polar solvent are xylene, toluene, white spirit, medium-boiling aromatic hydrocarbons, hexane, heptane and cyclohexane.

[0051] Preferred organic solvents are selected from polar alcohol solvents and non-polar hydrocarbon solvents, exemplified respectively by isopropanol and xylene. Particularly preferred organic solvents are selected from polar C2-C10 primary alcohol solvents and C3-C20 alicyclic hydrocarbons and aromatic hydrocarbon solvents.

[0052] The organic solvent may be one polar solvent, one non-polar solvent, or a mixture of one or more polar and non-polar organic solvents. The polar and non-polar solvents being as defined above.

[0053] In one embodiment, the total amount of organic solvent constitutes between 40-99 or 40-95, 40-90 , 40-85, or 40-80 or 40-75 or 40-70 % by weight of said post-cure treatment composition, such as between 45-99 or 45-95 or 45-90 or 45-85, or 45-80 or 45-75 or 45-70 %, such as between 50-99 or 50-95 or 50-90 or 50-85, or 50-80 or 50-75 or 50-70 % such as between 55-99 or 55-95 or 55-90 or 55-85, or 55-80 or 55-75 or 55-70 % , such as between 60-99 or 60-95 or 60-90 or 60-85, or 60-80 or 60-75 or 60-70 %, such as between 63-99 or 63-95 or 63-92%, such as between 65-99 or 65-95 or 65-90 or 65-85, or 65-80 or 65-75 or 65-70 %, such as between 70-99 or 70-95 or 70-90 or 70-85, or 70-80 or 70-75 %, such as between 75-99 or 70-95 or 70-90 or 70-85 or 70-80 %, such as between 80-99 or 80-95 or 80-90 or 80-85 % by weight of said post-cure treatment composition. In a preferred embodiment, the total amount of organic solvent constitutes between 50-90%, more preferably between 50-80%, such as between 50-70% by weight of said post-cure treatment composition.

[0054] If the composition contains less than 40% organic solvent, up to 40% by weight of water may be added, so the total content of organic solvent and water reaches 40-99% by weight of said post-cure treatment composition. Poly(oxyalkylene)-modified silicone oil

[0055] According to the invention, the post-cure treatment composition comprises one or more poly(oxyalkylene)-modified silicone oils. Poly(oxyalkylene)-modified silicone oils are widely used as surfactants and emulsifiers due to the content of both hydrophilic and lipophilic groups in the same molecule. "Poly(oxyalkylene)-modified silicone oil" usually refers to a silicone oil of hydrophobic nature, which has been modified with poly(oxyalkylene) moieties for example as internal side chains and / or terminally. Poly(oxyalkylene) refers to repeating units of oxygen and alkylene, typically ethylene and propylene.

[0056] Of particular interest are those poly(oxyalkylene)-modified silicone oils in which the relative weight of the poly( oxyalkylene) chains is 1 % or more of the total weight (e.g. 1-90 %), such as 5 % or more (e.g. 5-80 %), in particular 10 % or more (e.g. 10-70 %) of the total weight of the poly(oxyalkylene)-modified silicone oil. In one embodiment the relative weight of the poly(oxyalkylene) chains is in the range of 25-60 %, such as 30-50 %, of the total weight of the poly(oxyalkylene)-modified silicone oil. In another embodiment the relative weight of the poly(oxyalkylene) chains is in the range of 15-50 % such as 20-40 % by weight.

[0057] When calculating the amount of the poly(oxyalkylene) parts for a given poly(oxyalkylene)-modified silicone oil, it is typically fairly straightforward to distinguish it from the silicone part. However, in order to eliminate any doubt about any linkers between the two, it should be understood that the poly(oxyalkylene) parts include all atoms up to, but not including, the silicon atom which is adjacent to the poly(oxyalkylene) parts. As an example, in a structure such as of Formula (I) below, the residue of formula (i) accounts for the poly(oxyalkylene) part (the hydrophilic part).

[0058] In a preferred embodiment, the poly(oxyalkylene)-modified silicone oil has a number average molecular weight (Mn) in the range of 100-100,000 g / mol, such as in the range of 250-75,000 g / mol, in particular in the range of 500-50,000 g / mol, or 500-30,000 g / mol. In another preferred embodiment, the poly(oxyalkylene)-modified silicone oil has a number average molecular weight (Mn) in the range of 500-20,000 g / mol, such as 1,000-10,000 g / mol, or 1,000-7,500 g / mol, or even 1,500-5,000 g / mol.

[0059] In a preferred embodiment, the poly(oxyalkylene)-modified silicone oil has the structure according to formula (I) below:

[0060]

[0061] wherein,

[0062] each R1is independently selected from Ci-C5-a Ikyl (including linear or branched hydrocarbon groups) and aryl (e.g. phenyl (-CeHs)), preferably methyl;

[0063] each R5and R6are independently selected from R1, and the residue according to formula (i) below

[0064]

[0065] each R2is independently selected from -H, Ci-C4-alkyl (e.g. -CH3, -CH2CH3, - CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH3), phenyl (-C6H5), and Ci-C4-alkylcarbonyl (e.g. - C(=O)CH3, -C(=O)CH2CH3 and -C(=O)CH2CH2CH3), in particular -H, methyl and - C(=O)CH3;

[0066] each R3is independently selected from C2-C5 alkylene (e.g -CH2CH2-,- CH2CH(CH3), - CH2CH2CH2-, -CH2CH2CH2CH2-, -CH2CH(CH2CH3)-), arylene (e.g. 1,4-phenylene) and C2- C5-alkylene substituted with aryl (e.g. 1-phenyl ethylene), in particular from C2-C5- alkylene such as -CH2CH2- and -CH2CH(CH3)-;

[0067] each R4is selected from -(CH2)2-6-;

[0068] x is an integer of 0-2500 and y is an integer of 0-100, with the proviso that x+y is 1 or larger;

[0069] and n is 1-70;

[0070] with the proviso that at least R6or one of R5is a residue according to formula (i). In particular, three variations exists within the structure of formula (I). These are polysiloxanes having grafted thereto poly(oxyalkylene) chains; polysiloxanes having incorporated in the backbone thereof poly(oxyalkylene) chains; and combinations of those two variations.

[0071] Grafted chains:

[0072] In one embodiment, said poly(oxyalkylene)-modified silicone oil constitutes a polysiloxane having grafted thereto poly(oxyalkylene) chains.

[0073] An illustrative example of the structure of such poly(oxyalkylene)-modified silicone oils is the compound of formula (I) wherein:

[0074] both of R5are Rl;

[0075] R6is a residue according to formula (i);

[0076] x is an integer of 0-2500 and y is an integer of 1-100; and

[0077] R1, R2, R3, R4and n are as defined above.

[0078] Chains incorporated in backbone

[0079] In one embodiment, said poly(oxyalkylene)-modified silicone oil constitutes a polysiloxane having incorporated in the backbone thereof poly(oxyalkylene) chains.

[0080] An illustrative example of the structure of such poly(oxyalkylene)-modified silicone oils is the compound of formula (I) wherein:

[0081] at least one of R5is a residue according to formula (i);

[0082] X is an integer of 1-2500 and y is 0; and

[0083] R1, R2, R3, R4are as defined above.

[0084] In a particular embodiment, both of R5is a residue according to formula (i).

[0085] Combined incorporated and grafted chains

[0086] In one embodiment, said poly(oxyalkylene)-modified silicone oil constitutes a polysiloxane having incorporated in the backbone thereof poly(oxyalkylene) chains, and at the same time having grafted poly(oxyalkylene) chains to the backbone.

[0087] An illustrative example of the structure of such poly(oxyalkylene)-modified silicone oils is the compound of formula (I) wherein: 096

[0088] R6and at least one of R5constitute a residue according to formula (i);

[0089] X is an integer of 1-2500 and y is an integer of 1-100; and

[0090] R1, R2, R3, R4and n are as defined above.

[0091] In a particular embodiment, R6and both of R5constitute a residue according to formula (i). It should be understood that the one or more non-reactive poly(oxylalkylene)-modified silicone oils, may be of different types, e.g. two or more of the types described above.

[0092] In formula (I) including the three variations described above, the groups - CH2CH(CH3)-, -CH2CH(CH2CH3)-, etc. may be present in any of the two possible orientations. Similarly, it should be understood that the segments present x and y times typically are randomly distributed, or distributed as blocks, within the polysiloxane structure.

[0093] In these embodiments and variants, the poly(oxyalkylene) is preferably selected from polyoxyethylene, polyoxypropylene and poly(oxyethylene-co-oxypropylene), which sometimes are referred to as polyethylene glycol), polypropylene glycol) and polyethylene glycol-co-propylene glycol). Hence, in the above formula (I) each R3linking two oxygen atoms is preferably selected from -CH2CH2- and -CH2CH(CH3)-, whereas each R4linking a silicon atom and an oxygen atom preferably is selected from C2-Cs-a Ikyl.

[0094] Preferably, the non-reactive poly(oxylalkylene)-modified silicone oils are devoid of aromatic substituents.

[0095] The following embodiments relates to the compound of formula (I) as such, and the three variations described above.

[0096] In a preferred embodiment, n is 3-60, such as 3-50, such as 3-40, such as 4-20. In a further embodiment, n is 6-40, such as 6-30 or 6-25 or 6-20.

[0097] In a preferred embodiment, x is 3-1000, such as 3-500, such as 3-200, such as 3-150, such as 3-100, such as 3-50, such as 3-30, such as 3-20, such as 3-15 or 4-12. In a further embodiment, x is 6-200, such as 6-100, such as 6-50, such as 6-20. In a further embodiment, x is 10-200, such as 10-100, such as 10-50, such as 10-20. In another further embodiment, x is 20-200, such as 20-100, such as 20-50. 096

[0098] In a preferred embodiment, n+x is 3-1000, such as 3-500, such as 3-200, such as 3-150, such as 3-100, such as 3-50. In a further embodiment, n+x is 6-100, such as 6-50, such as 6-40 or 6-30.

[0099] In a preferred embodiment, x+y is 3-1000, such as 3-500, such as 3-200, such as 3-150, such as 3-100, such as 3-50, such as 3-30, such as 8-30, or x+y is 3-15, such as 4-12, or x+y is 6-20, such as 8-15.

[0100] Interesting commercially available non-reactive poly(oxyalkylene)-modified silicone oils are, DOWSIL 2-8692 from DOW, OFX-5103, OFX-190, OFX 5211, OFX-5220, OFX-5247, OFX-5329, OFX-5330, OFX-3667, and OFX-193 (all from Xiameter), BYK-331, BYK-378, BYK-Silclean 3701, BYK-Silclean 3710, BYK-3760, BYK-377 (all from BYK), DBE-621, CMS-222 from Gelest, CoatOSil 3501, Silwet 7280, CoatOSil 7210, CoatOSil 7200, CoatOSil 7602, CoatOSil 1220 (all from Momentive), TEGO Glide 410 and TEGO Glide 435 from Evonik industries, Borchi Gol LA200 (from Borchers) and KF352A, KF353, KF945, KF6012, KF-6015, KF6017, KF-6020, KF-6701 from Shin-Etsu. In the context of the invention, the poly(oxyalkylene)-modified silicone oil preferably has an HLB (hydrophilic-lipophilic balance) in the range of 1.5-14, such as 1.5-14, preferably 1.5-12, more preferably 1.5-10, herein determined according to Griffin's model using the equation "wt-% hydrophilic groups" / 5 (Reference: Griffin, W. C. Calculation of HLB values of non-ionic surfactants, J. Soc. Cosmet. Chem. 1954, 5, 249 — 256). The HLB parameter is a well-established characterisation method for non-ionic surfactants.

[0101] Poly(oxyalkylene)-modified silicone oils have further been described in for example WO 2011 / 076856 and WO 2014 / 117786.

[0102] Typically, the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 1-40 or 1-35 or 1-30 or 1-25 % by weight, such as between 2-40, or 2-35 or 2-30 or 2-25 % by weight, such as between 5-40, or 5-35 or 5-30 or 5-25 % by weight, such as between 10-40 or 10-35 or 10-30 or 10-25 % by weight, such as between 15-40 or 15-35 or 15-30 or 15-25 % by weight of said post-cure treatment composition. Preferably, the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 5-30%, more preferably between 10-30 %, such as between 15-25 % by weight of said post-cure treatment composition. 096

[0103] Further components

[0104] The post-cure treatment composition may comprise further components, which when present will typically have been included in the primary composition or the secondary composition before mixing.

[0105] Said further components may be selected from the non-limiting list of hindered amine light stabilizers, UV absorbers and additives as further described below.

[0106] Hindered amine light stabilizers (HALS)

[0107] In one embodiment, the post-cure treatment composition further comprises one or more hindered amine light stabilizer (HALS), comprising sterica lly hindered amine moieties which may for example be selected from 2,2,6,6-tetraalkyl piperidine derivatives. It has been demonstrated that such sterically hindered amine moieties when used in combination with constituents comprising poly(oxyalkylene) chains improves the fouling control performance of a polysiloxane-based fouling control paint coat (WO 2019 / 233985).

[0108] It appears that the existence of the sterically hindered amine moiety (e.g. a 2,2,6,6-tetraalkyl piperidine motif) plays an important role for the functionality of the hindered amine light stabilizer. Otherwise, it is envisaged that a broad range of derivatives are applicable, including those present as discrete molecules and those being part of oligomeric or polymeric structures.

[0109] In one embodiment, the hindered amine light stabilizer(s) comprise hindered amine moieties of general formula II:

[0110]

[0111] wherein

[0112] each R1 is independently selected from C1-C4 alkyl, preferably methyl; 096

[0113] R2 is selected from the list consisting of optionally substituted Ci-C3o-alkyl, optionally substituted C2-C3o-alkenyl, optionally substituted aryl, optionally substituted Ci-C3o-alkoxy, optionally substituted Ci-C3o-alkenyloxy, optionally substituted aryloxy, optionally substituted Ci-C3o-alkylcarbonyl, optionally substituted Ci-C3o-alkenylcarbonyl, and optionally substituted arylcarbonyl, -H and -OH (corresponding to N-O’);

[0114] R3 is an optionally substituted divalent group forming an N-heterocyclic 5-, 6- or 7-membered ring together with the intervening -C(R1)2-N(R2)-C(R1)2- group;

[0115] and wherein the R2 and / or R3 with the before-mentioned meanings may be linked to 1-200, such as 1-150, such as 1-100, preferably 1-50, such as 1-40 or 1-30 or 1-20 or 1-10 hindered amine moieties each independently having the general Formula II.

[0116] In some embodiments, R2 is selected from optionally substituted Ci-C3o-alkyl, optionally substituted Ci-C3o-alkenyl, optionally substituted aryl, optionally substituted Ci-Cs-alkoxy, optionally substituted Ci-C8-alkenyloxy, optionally substituted aryloxy, optionally substituted Ci-Cs-alkylcarbonyl, optionally substituted Ci-Cs-alkenylcarbonyl, and optionally substituted arylcarbonyl.

[0117] In one embodiment, R2 is selected from Ci-C4-alkyl, Ci-C4-alkoxy and Ci-C4-alkylcarbonyl. In some embodiments, R3 is selected from -CH2-C(~)-CH2- (corresponding to piperidine) and -CH2-N(~)-CH2- (corresponding to piperazine), in particular -CH2-C(~)-CH2-, where designates hydrogen atom(s) and / or the attachment point(s) for a substituent, a linker, a scaffold, a dendrimer, or a polymer, or the like.

[0118] In certain embodiments, R3 is selected from -CH2-C(R4)-CH2- (corresponding to piperidine) and -CH2-N(R4)-CH2- (corresponding to piperazine), in particular -CH2-C(R4)-CH2-, where R4 is as defined (generally and specifically) below for general formula III.

[0119] In some embodiments, the hindered amine light stabilizers are discrete molecules including only one hindered amine moiety, in particular a piperidine moiety of general formula III (below).

[0120] In other embodiments, the hindered amine light stabilizers are oligomers including, e.g. 2- 200, hindered amine moieties, in particular piperidine moieties of general formula III (below). In variants hereof, the moieties are linked together. 096

[0121] In a preferred embodiment, the hindered amine light stabilizer(s) are selected from 2, 2,6,6-tetraalkyl piperidine derivatives, i.e. the hindered amine moieties are 2,2,6,6-tetraalkyl piperidine moieties of general formula III:

[0122]

[0123] wherein R1 and R2 are defined as above; and R4 represents hydrogen atom(s) and / or the attachment point(s) for a polymer.

[0124] In some embodiments, R4 represents zero (where the 4-position of the piperidine is unsubstituted).

[0125] In some embodiments, R4 represent one or two substituents selected from Ci-Cso-alkyl, Ci-Cso-alkenyl, aryl, hydroxy, Ci-Cso-alkoxy, Ci-Cso-alkenyloxy, aryloxy, Ci-Cso-alkylcarbonyl, Ci-Cso-alkenylcarbonyl, arylcarbonyl, Ci-Cso-alkylcarbonyloxy, Ci-Cso-alkenylcarbonyloxy, and arylcarbonyloxy; and wherein the substituent R4 with the before-mentioned meanings may be linked to 1-200 hindered amine moieties each independently having the General Formula III.

[0126] In some embodiments, R4 represent one or two substituents selected from Ci-C8-alkoxy, Ci-Cs-alkenyloxy, aryloxy, Ci-Cs-alkylcarbonyloxy, Ci-Cs-alkenylcarbonyloxy, and arylcarbonyloxy.

[0127] In other embodiments, R4 represents two substituents forming a spiro structure, e.g. a spiro structure of a heterocyclyl nature.

[0128] Variants of hindered amine light stabilizers, such as 2,2,6,6-tetraalkyl piperidine derivatives, are very abundant in the literature and from commercial sources. Preferred are the following types: N-Ci-C3o-alkyl piperidine derivatives, N-Ci-C3o-alkenyl piperidine derivatives, N-aryl piperidine derivatives, N-Ci-Cso-alkoxy piperidine derivatives, N-Ci-Cso-alkenyloxy piperidine derivatives, N-aryloxy piperidine derivatives, N-Ci-C3o-alkylcarbonyl piperidine 096

[0129] derivatives, N-Ci-C3o-alkenylcarbonyl piperidine derivatives, and N-arylcarbonyl piperidine derivatives.

[0130] In some embodiments the following types are more preferred: N-Ci-C3o-alkyl piperidine derivatives, N-Ci-C3o-alkenyl piperidine derivatives, and N-aryl piperidine derivatives, in particular N-Ci-C3o-alkyl piperidine derivatives.

[0131] In other embodiments the following types are more preferred: N-Ci-C3o-alkoxy piperidine derivatives, N-Ci-C3o-alkenyloxy piperidine derivatives, and N-aryloxy piperidine derivatives, in particular N-Ci-C30-alkoxy piperidine derivatives.

[0132] In still other embodiments the following types are more preferred: N-Ci-C3o-alkylcarbonyl piperidine derivatives, N-Ci-C3o-alkenylcarbonyl piperidine derivatives, and N-arylcarbonyl piperidine derivatives, in particular N-Ci-C3o-alkylcarbonyl piperidine derivatives.

[0133] Without being bound to any particular theory, it is envisaged that the pKa values of the 2,2,6,6-tetraalkyl piperidine derivatives preferably should be below 8.5. Hence, it is preferred that the N is substituted (i.e. not N-H). More preferably, the pKa is below 8.0, such as below 7.0, e.g. below 6.0 or even below 5.0.

[0134] Furthermore, it is preferred that the 2,2,6,6-tetraalkyl piperidine derivatives (as well as generally the sterically hindered amines) in the overall structure of formula II or III do not include any primary amines or secondary amines. Furthermore, the structures of formula II or III should preferably not include any non-hindered tertiary amines.

[0135] In the present context, any alkylene and alkenylene moieties include both linear and branched moieties. For example, Ci-C3o-alkyl includes linear and branched Ci-C3o alkyl. When any R group (in particular Rl, R2, R3 and R4) are described as being "optionally substituted", this means that that may be substituted at any suitable position with halogen (-F, -Cl, -Br or -I), -C1-C4 alkyl, or -OH. The term "spiro" has its regular meaning in organic chemistry; i.e. two or more rings which share a common atom.

[0136] The hindered amine light stabilizer moieties, such as the derivates of formula II or III, may be present in the post-cure treatment composition as discrete molecules and / or as part of an oligomeric or polymeric structure. In one embodiment, the sterically hindered amine moieties, such as the derivates of formula II or III, are present in the post-cure treatment 096

[0137] composition as discrete molecules. In another embodiment, the sterica lly hindered amine moieties are present in the post-cure treatment composition as part of an oligomeric or polymeric structure.

[0138] Examples of hindered amine light stabilizers, such as in particular 2,2,6,6-tetraalkyl piperidine derivatives are further described in WO 2019 / 233985 and WO 2016 / 105974, which are incorporated herein by reference.

[0139] Illustrative examples of commercial hindered amine light stabilizers of the 2, 2,6,6-tetramethyl piperidine type are: Sabostab UV 65 (N-CH3), Sabostab UV 40 (N-H), Sabostab UV 79 (N-H) from Sabo S.p.A.; Hostavin 3058 (N-Acyl), Hostavin 3070 (Oligomeric) and Hostavin 3050 from Clariant; Tinuvin 622 (Oligomeric), Tinuvin 144 (N-CH3), Flamestab NOR 116 (N-O-R), Chimassorb 944 (N-H), Tinuvin 249 (N-O-R), Tinuvin 440 (N-Acyl), Tinuvin 152 (N-O-R), Tinuvin 123 (N-O-R), Uvinul 4050 H (N-H), Lignostab 1198 (N-O», monomer), Uvinul 5050 H (N-H, polymeric) from BASF; ADK STAB LA-52 (N-CH3), ADK STAB LA-68 (N-H), ADK STAB LA-82 (N-CH3) from Adeka Palmarole; and UBS-0822 (N-H, siloxane), UBS-0541 (N-H, siloxane) from Gelest. Preferably Tinuvin 123 (N-O-R), Hostavin 3050 and Tinuvin 292 If hindered amine light stabilizer(s) are present in the post-cure treatment composition, they will typically be present in a total amount of up to 10 % by weight of the composition, such as up to 5 %, 4 % 3 % or 2 % or 1 % by weight of the composition, preferably 0.01-10 % by weight of the composition, such as in an amount of 0.1-5 %, such as 0.1-4 % or 0.1-3 % or 0.1-2 % or 0.1-1 % by weight of the composition, or in an amount of 0.01-4 %, such as 0.01-3 % or 0.01-2 % or 0.01-1 % by weight of the composition.

[0140] Any hindered amine light stabilizer(s) included in the composition are typically included in the secondary composition before mixing the primary and the secondary composition. UV-absorbers

[0141] The post-cure treatment composition may further comprise one or more UV absorbers. UV absorbers are light stabilizers that function by absorbing damaging UV radiation, protecting the polymer from degradation by UV-light, due to their high UV absorbing capability and dissipate the absorbed UV energy as heat without altering the properties of the polymer. This mechanism is complementary to the free radical scavenging mechanism of hindered 096

[0142] amine light stabilizers, and as a result UV-absorbers may be used alone or in combination with hindered amine light stabilizers to achieve higher performance.

[0143] However, in one embodiment, the UV-absorber is present without the concurrent presence of a hindered amine light stabilizer, as described above.

[0144] Examples of UV-absorbers are benzotriazoles, benzoates, benzophenones, cyanoacrylates, oxanilides or triazines.

[0145] Preferred UV-absorbers are benzotriazoles, or triazines.

[0146] Interesting commercially available UV-absorbers are Tinuvin 99-2, Tinuvin 326, Tinuvin 900, Tinuvin 1130, ADK STAB LA-29, ADK STAB LA-46 and ADK STAB 1413.

[0147] If present, the total amount of UV-absorber typically constitutes

[0148] up to 10 % by weight of the composition, such up to 5 %, 4 % 3 % or 2 % or 1 % by weight of the composition, preferably 0.01-10 % by weight of the composition, such as in an amount of 0.1-5 %, such as 0.1-4 % or 0.1-3 % or 0.1-2 % or 0.1-1 % by weight of the composition, or in an amount of 0.01-4 %, such as 0.01-3 % or 0.01-2 % or 0.01-1 % by weight of the composition.

[0149] Any UV absorber(s) included in the composition are typically included in the secondary composition before mixing the primary and the secondary composition.

[0150] Biocides

[0151] The claimed post-cure treatment provides an efficient anti-fouling effect without including biocides in the post-cure treatment composition. Thus, in a preferred embodiment, the postcure treatment composition does not contain any biocides for the purpose of providing antifouling effect. Although inclusion of biocides is not preferred, the post-cure treatment composition may comprise biocides. Biocides relevant for fouling-control systems are well known by the skilled person and may for example be selected from the biocides listed in WO 2023 / 036923.

[0152] Additives

[0153] The post-cure treatment composition may comprise additives such as rheological modifiers (including thixotropic agents, thickening agents and anti-settling agents), dispersing agents, 096

[0154] wetting agents, surfactants, binders, plasticizers and dyes. Examples of rheological modifiers are colloidal silica, hydrated aluminium silicate (bentonite), aluminium tristearate, aluminium monostearate, xanthan gum, chrysotile, pyrogenic silica, hydrogenated castor oil, hydroxy ethyl cellulose, organo-modified clays, polyamide waxes and polyethylene waxes. The rheological modifiers are typically present in the post-cure treatment composition in an amount of 0-10 % by weight, more preferably 0.1-5.0 % by weight, even more preferably 0.1-2.0 % by weight. Additives are typically included in the primary composition before mixing the primary and the secondary composition.

[0155] Post-cure treatment composition

[0156] In one aspect of the present invention, a post-cure treatment composition is provided that comprises one or more organic solvents, one or more poly(oxyalkylene)-modified silicone oils, and one or more rheological modifiers. Examples of rheological modifiers are provided above. Also provided is a use of a post-treatment composition for improving the fouling contorl properties of a fouling control paint, wherein the composition comprises one or more organic solvents, and one or more poly(oxyalkylene)-modified silicone oils, as defined hereinabove. In some cases, the composition used is that of the aspect that is described hereinbelow.

[0157] The post-cure treatment composition may comprise two or more, preferably three or more, rheological modifiers. Preferably, the rheological modifiers comprise at least one polyamide wax rheological modifier. Suitable examples of such polyamide wax rheological modifiers are known in the art.

[0158] The rheological modifiers are typically present in the post-cure treatment composition in an amount of 0.1-10 % by weight, preferably 0.1-5.0 % by weight, more preferably 0.1-2.0 % by weight. It will be understood by the person skilled in the art that these weight% refer to each rheological modifier included in the post-cure treatment composition.

[0159] When there are two or more rheological modifiers present in the post-cure treatment composition, the combined weight of the two or more rheological modifiers is 2 to 20% by weight of the post-cure treatment composition. Preferably, the combined weight of the two or more rheological modifiers is 5 to 20% by weight of the post-cure treatment composition. More preferably, the combined weight of the two or more rheological modifiers is 7 to 15% 096

[0160] by weight of the post-cure treatment composition. In such cases, each rheological modifier may be present in an amount of 0.1 to 10% by weight of the post-cure treatment composition.

[0161] In some cases, the post-cure treatment composition comprises one or more organic solvents, one or more poly(oxyalkylene)-modified silicone oils, and two or more rheological modifiers, where the combined weight of the two or more rheological modifiers is 2 to 20% by weight of the post-cure treatment composition and the two or more rheological modifiers comprise at least one polyamide wax rheological modifier. In such cases, each rheological modifier may be present in an amount of 0.1 to 10% by weight of the post-cure treatment composition.

[0162] The one or more organic solvents included in the post-cure treatment composition are as defined above. For example, the total amount of organic solvent may constitute between 40-99 or 40-95, 40-90, 40-85, or 40-80 or 40-75 or 40-70 % by weight of said post-cure treatment composition, such as between 45-99 or 45-95 or 45-90 or 45-85, or 45-80 or 45-75 or 45-70 %, such as between 50-99 or 50-95 or 50-90 or 50-85, or 50-80 or 50-75 or 50-70 % such as between 55-99 or 55-95 or 55-90 or 55-85, or 55-80 or 55-75 or 55-70 % , such as between 60-99 or 60-95 or 60-90 or 60-85, or 60-80 or 60-75 or 60-70 %, such as between 63-99 or 63-95 or 63-92%, such as between 65-99 or 65-95 or 65-90 or 65-85, or 65-80 or 65-75 or 65-70 %, such as between 70-99 or 70-95 or 70-90 or 70-85, or 70-80 or 70-75 %, such as between 75-99 or 70-95 or 70-90 or 70-85 or 70-80 %, such as between 80-99 or 80-95 or 80-90 or 80-85 % by weight of said post-cure treatment composition.

[0163] In a preferred embodiment, the total amount of organic solvent constitutes between 50-90%, more preferably between 50-80%, such as between 50-70% by weight of said post-cure treatment composition. As will be understood by the person skilled in the art, these ranges are combinable with the above ranges for the amount(s) of rheological modifier(s).

[0164] In some cases, the post-cure treatment composition comprises one or more organic solvents, one or more poly(oxyalkylene)-modified silicone oils, and two or more rheological modifiers, where the total amount of organic solvent constitutes between 50-90% by weight of the post-cure treatment composition, and the combined weight of the two or more rheological modifiers is 2 to 20% by weight of the post-cure treatment composition and the 096

[0165] two or more rheological modifiers comprise at least one polyamide wax rheological modifier. In such cases, each rheological modifier may be present in an amount of 0.1-10% by weight of the post-cure treatment composition.

[0166] If the composition contains less than 40% organic solvent, up to 40% by weight of water may be added, so the total content of organic solvent and water reaches 40-99% by weight of said post-cure treatment composition.

[0167] The one or more organic solvent may be selected from polar solvents and non-polar solvents as defined above. The one or more organic solvent may comprise a hydrocarbon organic solvent in some cases. The hydrocarbon organic solvent is preferably a non-polar hydrocarbon organic solvent as defined above.

[0168] Hence, in some cases, the post-cure treatment composition comprises one or more organic solvents comprising a hydrocarbon organic solvent, preferably a non-polar hydrocarbon organic solvent, one or more poly(oxyalkylene)-modified silicone oils, and one or more rheological modifiers. The rheological modifiers may comprise a polyamide wax rheological modifier.

[0169] In some cases, the post-cure treatment composition comprises one or more organic solvents comprising a hydrocarbon organic solvent, preferably a non-polar hydrocarbon organic solvent, one or more poly(oxyalkylene)-modified silicone oils, and two or more rheological modifiers, the rheological modifiers comprising a polyamide wax rheological modifier, where the combined weight of the two or more rheological modifiers is 2 to 25% by weight of the post-cure treatment composition.

[0170] In some cases, the post-cure treatment composition comprises one or more organic solvents comprising a hydrocarbon organic solvent, preferably a non-polar hydrocarbon organic solvent, one or more poly(oxyalkylene)-modified silicone oils, and two or more rheological modifiers, where the total amount of organic solvent constitutes between 50-90% by weight of the post-cure treatment composition, and the combined weight of the two or more rheological modifiers is 2 to 20% by weight of the post-cure treatment composition and the two or more rheological modifiers comprise at least one polyamide wax rheological modifier. 096

[0171] In such cases, each rheological modifier may be present in an amount of 0.1-10% by weight of the post-cure treatment composition.

[0172] The composition is suitably free of a binder, in particular a polysiloxane binder.

[0173] The poly(oxyalkylene)-modified silicone oil is as defined above.

[0174] In some cases, the post-cure treatment composition comprises one or more organic solvents, one or more poly(oxyalkylene)-modified silicone oils, and one or more rheological modifiers, wherein the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 5-30% by weight of said post-cure treatment composition. The total amount of organic solvent may further constitute 50-90% by weight of the post-cure treatment composition. In such cases, each rheological modifier may be present in an amount of 0.1-10% by weight of the post-cure treatment composition.

[0175] In some cases, the post-cure treatment composition comprises one or more organic solvents comprising a hydrocarbon organic solvent, preferably a non-polar hydrocarbon organic solvent, one or more poly(oxyalkylene)-modified silicone oils, and one or more rheological modifiers, wherein the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 5-30% by weight of said post-cure treatment composition. The total amount of organic solvent may further constitute 50-90% by weight of the post-cure treatment composition. In such cases, each rheological modifier may be present in an amount of 0.1-10% by weight of the post-cure treatment composition. When two or more rheological modifiers are present, the combined weight of the two or more rheological modifiers is 2 to 20% by weight of the post-cure treatment composition. The two or more rheological modifiers may comprise at least one polyamide wax rheological modifier.

[0176] The composition may further comprise:

[0177] i) one or more hindered amine light stabilizers; and / or

[0178] ii) one or more UV-absorbers.

[0179] Details of the hindered amine light stabilizers; and the UV-absorbers are as set out above. The one or more hindered amine light stabilizer may be present in an amount of 0.01-10% by weight of the post-cure treatment composition, such as in an amount of 0.1-5%, such as 096

[0180] 0.1-4% or 0.1-3% or 0.1-2% or 0.1-1% by weight of the composition, or in an amount of 0.01-4%, such as 0.01-3% or 0.01-2% or 0.01-1% by weight of the composition.

[0181] Preparation of the post-cure treatment composition

[0182] The post-cure treatment composition was prepared from a primary composition and a secondary composition. The primary composition comprises the one or more organic solvent, and the secondary composition comprises the one or more poly(oxyalkylene)-modified silicone oil. The primary and the secondary composition may comprise further constituents such as hindered amine light stabilizers, UV-absorbers and additives.

[0183] When the post-cure treatment composition comprises one or more rheological modifier as defined herein, the one or more rheological modifier is present in the primary composition. The post-cure treatment composition can be prepared by first preparing a primary composition comprising the one or more organic solvents and optional additives as described above, and separately preparing a secondary composition comprising poly(oxyalkylene)-modified silicone oil and optionally hindered amine light stabilizers and UV absorbers as described above, and subsequently mixing the primary and secondary compositions. One particular method for preparation of the post-cure treatment composition is described below.

[0184] All components for the primary composition were mixed in a highspeed dissolver equipped with an impeller disc at 3500 rpm for at least 15 min. The components for the secondary composition may be mixed by hand for at least 2 min. The primary composition and the secondary composition were mixed together by hand, shortly before application.

[0185] Alternatively, the primary composition may be mixed in a pearl mill until the temperature reaches 60 °C for 30 minutes. Thereafter, the composition is filtered through a colander. Similar methods and variations of the method described herein may be utilised by the person skilled in the art.

[0186] It should be understood that when reference is made to the "post-cure treatment composition", it refers to the mixed composition comprising the constituents in the desired amounts ready to be applied on the fouling control coat.

[0187] Application of the post-cure treatment composition 096

[0188] The post-cure treatment composition according to the invention is applied on top of a fouling control coat, preferably a polysiloxane based coat.

[0189] The term "applying" is used in its normal meaning within the paint industry. Thus, "applying" is conducted by means of any conventional means, e.g. by brush, by roller, by spraying, etc. The most commercially interesting way of "applying" the post-cure treatment composition is by roller or by spraying. Hence, the post-cure treatment composition is preferably sprayable. Spraying is effected by means of conventional spraying equipment known to the person skilled in the art. The post-cure treatment composition is typically applied in a wet film thickness of 30-400 pm, such as 50-400 pm, e.g. 75-300 pm, or 75-200, such as about 100 pm.

[0190] Typically the post-cure treatment composition is applied in an amount of 0.03 to 0.4 litre per square meter, such as 0.05 to 0.4 litre per square meter, e.g. 0.075 to 0.3 litre pr square meter.

[0191] After having been in contact with the surface for at least 2 hours, the remaining composition that is left on the surface may be removed either by direct removal or by dissolution when sailing. Said composition is typically removed with water e.g. by flushing the surface with water or by washing with a brush or a sponge or by air-blowing. The water may optionally contain soap which is optionally subsequently removed by washing with water. Another way of removing the excess composition is by polishing e.g by polishing with a cloth. In one embodiment, excess composition is left on the surface without removal.

[0192] The term "at least a part of the surface of a substrate" refers to the fact that the post-cure treatment composition may be applied to any fraction of the surface. The post-cure treatment composition is applied to at least a part of the substrate (e.g. a fouling control coat) where the surface may come in contact with water, e.g. sea-water.

[0193] The term "substrate" in the present context is intended to mean the top coat of a fouling control coating. The substrate typically comprises a polysiloxane-based coat. Alternative substrates such as other non-erodible coatings may also be relevant, such as acrylate coatings.

[0194] The term "surface" is used in its normal sense, and refers to the exterior boundary of an object. In the context of the invention, the post-cure treatment composition is applied on 096

[0195] the surface of a fouling control paint coat. The fouling control paint coat, whereto the postcure treatment composition is applied, is typically present on the surface of a marine structure, such as vessels (including but not limited to boats, yachts, motorboats, motor launches, ocean liners, tugboats, tankers, container ships and other cargo ships, submarines, and naval vessels of all types). In one embodiment, the fouling control paint coat is present on pipes, shore and off-shore machinery, constructions such as piers, pilings, bridge substructures, water-power installations and structures, underwater oil well structures etc. In one embodiment, the post-cure treatment composition is applied onto a freshly applied fouling control paint coat as previously described. In one embodiment, the post-cure treatment composition is applied on an aged coat, e.g. a worn out fouling control paint coat. NUMBERED EMBODIMENTS

[0196] In the following, embodiments of the invention are disclosed. It should be understood that the various aspects, embodiments, implementations and features of the invention mentioned herein may be claimed separately, or in any combination.

[0197] El. A method for post-cure treatment of a fouling control paint coat, said method comprising the following steps:

[0198] a. applying a post-cure treatment composition on the surface of said fouling control paint coat;

[0199] b. allowing the post-cure treatment composition to stay in contact with the surface of said fouling control paint coat for a period of at least 2 hours;

[0200] wherein said post-cure treatment composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils.

[0201] E2. The method according to embodiment El, wherein the total amount of organic solvent constitutes between 40-99 or 40-95, 40-90 , 40-85, or 40-80 or 40-75 or 40-70 % by weight of said post-cure treatment composition, such as between 45-99 or 45-95 or 45-90 or 45-85, or 45-80 or 45-75 or 45-70 %, such as between 50-99 or 50-95 or 50-90 or 50-85, or 50-80 or 50-75 or 50-70 % such as between 55-99 or 55-95 or 55-90 or 55-85, or 55-80 or 55-75 or 55-70 % , such as between 60-99 or 60-95 or 60-90 or 60-85, or 60-80 or 60-75 or 60-70 %, such as between 63-99 or 63-95 or 63-92%, such as between 65-99 or 65-95 or 65-90 or 65-85, or 096

[0202] 65-80 or 65-75 or 65-70 %, such as between 70-99 or 70-95 or 70-90 or 70-85, or 70-80 or 70-75 %, such as between 75-99 or 70-95 or 70-90 or 70-85 or 70-80 %, such as between SO-99 or 80-95 or 80-90 or 80-85 by weight of said post-cure treatment composition.

[0203] E3. The method according to any of embodiments E1-E2, wherein the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 1-40 or 1-35 or 1-30 or 1-25 % by weight, such as between 2-40, or 2-35 or 2-30 or 2-25 % by weight, such as between 5-40, or 1-35 or 5-30 or 5-25 % by weight, such as between 10-40 or 10-35 or 10-30 or 10-25 % by weight, such as between 15-40 or 15-35 or 15-30 or 15-25 % by weight of said composition. E4. The method according to any of embodiments E1-E3, wherein the total amount of organic solvent constitutes between 40-99 or 40-95, 40-90 , 40-85, or 40-80 or 40-75 or 40-70 % by weight of said post-cure treatment composition, such as between 45-99 or 45-95 or 45-90 or 45-85, or 45-80 or 45-75 or 45-70 %, such as between 50-99 or 50-95 or 50-90 or 50-85, or 50-80 or 50-75 or 50-70 % such as between 55-99 or 55-95 or 55-90 or 55-85, or 55-80 or 55-75 or 55-70 % , such as between 60-99 or 60-95 or 60-90 or 60-85, or 60-80 or 60-75 or 60-70 %, such as between 63-99 or 63-95 or 63-92%, such as between 65-99 or 65-95 or 65-90 or 65-85, or 65-80 or 65-75 or 65-70 %, such as between 70-99 or 70-95 or 70-90 or 70-85, or 70-80 or 70-75 %, such as between 75-99 or 70-95 or 70-90 or 70-85 or 70-80 %, such as between 80-99 or 80-95 or 80-90 or 80-85 by weight of said composition; and the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 1-40 or 1-35 or 1-30 or 1-25 % by weight, such as between 2-40, or 2-35 or 2-30 or 2-25 % by weight, such as between 5-40, or 1-35 or 5-30 or 5-25 % by weight, such as between 10-40 or 10-35 or 10-30 or 10-25 % by weight, such as between 15-40 or 15-35 or 15-30 or 15-25 % by weight of said composition.

[0204] E5. The method according to any of embodiments E1-E4, wherein said post-cure treatment composition is allowed to stay in contact with the surface of said fouling control paint coat for a period of at least 3 hours, preferably at least 4 or 5 hours, more preferably at least 6, 7, 8, 9 or 10 hours, such as at least 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 or 24 hours. E6. The method according to any of any of any of embodiments E1-E5, wherein said postcure treatment composition is allowed to stay in contact with the surface of said fouling control paint coat for a period between 4-48 hours, such as between 4-40 hours, 4-36 hours, 096

[0205] 4-32 hours, 4-28 hours or 4-24 hours, or between 6-48 hours, such as between 6-40 hours, 6-36 hours, 6-32 hours, 6-28 hours or 6-24 hours.

[0206] E7. The method according to any of any of embodiments E1-E6, wherein said post-cure treatment composition is prepared from a primary composition comprising one or more organic solvents and a secondary composition comprising poly(oxyalkylene)-modified silicone oil.

[0207] E8. The method according to embodiment E7, wherein said primary composition comprises at least 70 % by weight, such as at least 80 % by weight, such as at least 90 % by weight, preferably at least 95 % by weight, such as at least 99 wt% of organic solvent; and said secondary composition comprises least 1 % by weight, such as at least 5 % by weight, such as at least 10 % by weight, such as at least 15 % by weight, such as at least 20 % by weight of poly(oxyalkylene)-modified silicone oil.

[0208] E9. The method according to any embodiments E1-E8, wherein said method further comprises the following step:

[0209] c. removing excess post-cure treatment composition from the surface of said fouling control paint coat after step b,

[0210] wherein said removal is performed by flushing the surface with water or by washing with a brush or a sponge.

[0211] E10. The method according to embodiment E9, wherein said removal is further performed by washing the surface with soap and subsequently rinsing with water.

[0212] Ell. The method according to any of embodiments E1-E10, wherein said poly(oxyalkylene)-modified silicone oil is characterised by having an HLB value in the range of 1.5-14, such as 1.5-14, preferably 1.5-12, more preferably 1.5-10.

[0213] E12. The method according to any of embodiments El-Ell, wherein the poly(oxyalkylene) moiety of said poly(oxyalkylene)-modified silicone oil is selected from polyoxyethylene; polyoxypropylene and / or poly(oxyethylene-co-oxypropylene), preferably polyoxyethylene. E13. The method according to any of embodiments E1-E12, wherein said post-cure treatment composition is applied at a wet film thickness of 30-400 pm, such as 50-400 pm, e.g. 75-300 pm, or 75-200, such as about 100 pm. 096

[0214] E14. The method according to any of embodiments E1-E13, wherein said post-cure treatment composition and / or said secondary composition further comprises

[0215] i) one or more hindered amine light stabilizers; and / or

[0216] ii) one or more UV-absorbers.

[0217] E15. The method according to embodiment E14, wherein said one or more hindered amine light stabilizer is selected from 2,2,6,6-tetraalkyl piperidine derivatives.

[0218] E16. The method according to any of embodiments E14-E15, wherein said one or more hindered amine light stabilizer is present in an amount of up to 10 % by weight of the postcure treatment composition, such up to 5 %, 4 % 3 % or 2 % or 1 % by weight of the composition.

[0219] E17. The method according to any of embodiments E14-E16, wherein said one or more hindered amine light stabilizer is present in an amount of 0.01-10 % by weight of the postcure treatment composition, such as in an amount of 0.1-5 %, such as 0.1-4 % or 0.1-3 % or 0.1-2 % or 0.1-1 % by weight of the composition, or in an amount of 0.01-4 %, such as 0.01-3 % or 0.01-2 % or 0.01-1 % by weight of the composition.

[0220] E18. The method according to any of embodiments E14-E17, wherein said one or more UV-absorber is selected from the list consisting of benzotriazoles, benzoates, benzophenones and triazines.

[0221] E19. The method according to any of embodiments E14-E18, wherein said one or more UV absorber is present in an amount of up to 10 % by weight of the post-cure treatment composition, such up to 5 %, 4 % 3 % or 2 % or 1 % by weight of the composition.

[0222] E20. The method according to any of embodiments E14-E19, wherein said one or more UV absorber is present in an amount of 0.01-5% by weight of the post-cure treatment composition, such as in an amount of 0.1-5%, such as 0.1-4% or 0.1-3% or 0.1-2% or 0.1-1% by weight of the composition, or in an amount of 0.01-4%, such as 0.01-3% or 0.01-2% or 0.01-1% by weight of the composition.

[0223] E21. The method according to any of embodiments E1-E21, wherein said post-cure treatment composition and / or said primary composition further comprises one or more 096

[0224] additives such as one or more rheological modifiers, such as thixotropic agents, thickening agents and / or anti-settling agents.

[0225] E22. The method according to embodiment E21, wherein said rheological modifiers are selected from colloidal silica, hydrated aluminium silicate (bentonite), aluminium tristearate, aluminium monostearate, xanthan gum, chrysotile, pyrogenic silica, hydrogenated castor oil, hydroxy ethyl cellulose, organo-modified clays, polyamide waxes and polyethylene waxes. E23. The method according to any of embodiments E21-E22, wherein said rheological modifiers are present in an amount of 0-10 % by weight, more preferably 0.1-5.0 % by weight, even more preferably 0.1-2.0 % by weight.

[0226] E24. The method according to any of embodiments E1-E23, wherein said post-cure treatment composition is applied by brush or roller or spray application, preferably by spray application.

[0227] E25. The method according to any of embodiments E1-E24, wherein said fouling control paint coat has been applied onto the outer surface of a substrate, wherein said substrate is a substrate for immersion in water such as a native vessel.

[0228] E26. The method according to any of embodiments E1-E25, comprising the initial step of identifying a substrate comprising on the outer surface said fouling control paint coat.

[0229] E27. The method according to any of embodiments E1-E26, wherein said fouling control paint coat is a non-erodible paint coat, preferably a polysiloxane based paint coat.

[0230] E28. The method according to any of embodiments E1-E27, wherein said fouling control paint coat is a freshly applied coat.

[0231] E29. The method according to any of embodiments E1-E28, wherein said fouling control paint coat is an aged coat, such as a worn-out coat.

[0232] E30. The method according to any of embodiments E1-E29, wherein said fouling control paint coat constitutes the outermost layer of an fouling control system further comprising a primer and / or a tie coat.

[0233] E31. The method according to any of embodiments E1-E30, wherein said post-cure treatment composition consists or consists essentially of:

[0234] - one or more organic solvents, 096

[0235] - one or more poly(oxyalkylene)-modified silicone oils,

[0236] - optionally, one or more hindered amine light stabilizers, preferably being a 2, 2,6,6-tetraalkyl piperidine derivative,

[0237] - optionally, one or more UV-absorbers, and

[0238] - one or more, preferably two or more, rheological modifiers.

[0239] E32. The method according to any of embodiments E1-E31, wherein said post-cure treatment composition comprises or consists of:

[0240] - at least 60 % by weight of said one or more organic solvents,

[0241] - 1-25 % by weight of said composition of one or more poly(oxyalkylene)-modified silicone oils,

[0242] - 1-10 % by weight of said composition of one or more hindered amine light stabilizers, preferably being a 2,2,6,6-tetraalkyl piperidine derivative,

[0243] - 0.1-10 % by combined weight of said composition of two or more rheological modifiers. E33. The method according to any of embodiments E1-E32, wherein said post-cure treatment composition comprises:

[0244] - at least 60% by weight of said one or more organic solvent,

[0245] - 1-25% by weight of said one or more poly(oxyalkylene)-modified silicone oils,

[0246] - 2-25% by combined weight of said composition of two or more rheological modifiers.

[0247] E34. The method according to embodiment E33, wherein the one or more organic solvent comprises a hydrocarbon non-polar organic solvent.

[0248] E35. The method according to embodiment E33 or E34, wherein the two or more rheological modifiers comprise a polyamide wax rheological modifier.

[0249] E.36 Use of a method according to any of embodiments E1-E35 for improving the fouling control properties of a fouling control paint coat.

[0250] E.37 Use of a post-cure treatment composition in a method according to any of embodiments E1-E32 for improving the fouling control properties of a fouling control paint, wherein the post-cure treatment composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils. 096

[0251] E38. A fouling control paint coat, preferably a non-erodible paint coat such as a polysiloxane-based paint coat that has been treated by the method according to any of embodiments El-E35.

[0252] E39. The fouling control paint coat according to embodiment E38 having on at least a part of the outer surface a multilayer system comprising

[0253] i) one or more layers of a cured primer;

[0254] ii) one or more layers of cured tie coat, and

[0255] iii) one or more further layers of cured fouling control coat;

[0256] wherein said fouling control coat has been treated by the method according to any of embodiments E1-E35.

[0257] E40. A post-cure treatment composition for a fouling control paint comprising one or more organic solvents, one or more poly(oxyalkylene)-modified silicone oils, and one or more rheological modifiers.

[0258] E41. The composition according to embodiment E40, wherein the composition comprises two or more rheological modifiers.

[0259] E42. The composition according to embodiment E41, wherein the composition comprises three or more rheological modifiers.

[0260] E43. The composition according to embodiment E41 or E42, wherein the two or more rheological modifiers comprise a polyamide wax rheological modifier.

[0261] E44. The composition according to any of embodiments E40-E43, wherein the one or more organic solvent comprises a hydrocarbon organic solvent.

[0262] E45. The composition according to embodiment E44, wherein the hydrocarbon organic solvent is a non-polar hydrocarbon organic solvent.

[0263] E46. The composition according to any of embodiments E40-E45, wherein the composition is free of a polysiloxane binder.

[0264] E47. The composition according to any of embodiments E40-E46, wherein the total amount of organic solvent constitutes between 40-99 % by weight of said post-cure treatment 096

[0265] composition, preferably between 50-90% by weight of said post-cure treatment composition.

[0266] E48. The composition according to any of embodiments E40-E47, wherein the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 1-40 % by weight of said postcure treatment composition, preferably between 5-30% by weight of said post-cure treatment composition.

[0267] E49. The composition according to any of embodiments E40-E48, wherein said poly(oxyalkylene)-modified silicone oil is characterized by having an HLB value in the range of 1.5-14, preferably 1.5-12.

[0268] E50. The composition according to any of embodiments E40-E49, wherein said poly(oxyalkylene)-modified silicone oil has the structure according to formula (I):

[0269]

[0270] wherein,

[0271] each R1is independently selected from Ci-C5-a Ikyl and aryl (e.g. phenyl (-C6H5)); each R5and R6are independently selected from R1, and the residue according to formula (i), provided that at least one R5is a residue according to formula (i);

[0272]

[0273] each R2is independently selected from -H, Ci-C4-alkyl, phenyl, and C1-C4- alkylcarbonyl;

[0274] each R3is independently selected from C2-C5 alkylene, arylene and C2-Cs-alkylene substituted with aryl;

[0275] each R4is selected from — (CH2)2-6-; 096

[0276] x is an integer of 1-2500; and

[0277] y is 0.

[0278] E51. The composition according to any of embodiments E40-E50, wherein the one or more rheological modifier is present in an amount of 0.1-10% by weight of the post-cure treatment composition.

[0279] E52. The composition according to any of embodiments E40-E51, wherein the composition comprises two or more rheological modifiers and the combined weight of the two or more rheological modifiers is 2 to 20% by weight of the post-cure treatment composition.

[0280] E53. An article comprising a treated fouling control coating formed by the method according to any of embodiments E1-E35, wherein the article is a marine structure or part thereof. E54. Use of a post-cure treatment composition for improving the fouling control properties of a fouling control paint, wherein the composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils.

[0281] E55. Use of a post-cure treatment composition for improving the fouling control properties of a fouling control paint, wherein the composition is as defined in any of embodiments E40 to E52.AII references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference in their entirety and to the same extent as if each reference were independently and specifically indicated to be incorporated by reference and were set forth in its entirety herein (to the maximum extent permitted by law), regardless of any separately provided incorporation of particular documents made elsewhere herein. The use of the terms "a" and "an" and "the" and similar referents in the context of describing the invention are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. For example, the phrase "the composition" is to be understood as referring to various "compositions" of the invention or particular described aspect, unless otherwise indicated.

[0282] The description herein of any aspect or aspect of the invention using terms such as "comprising", "having," "including" or "containing" with reference to an element or elements is intended to provide support for a similar aspect or aspect of the invention that "consists of", "consists essentially of" or "substantially comprises" that particular element or 096

[0283] elements, unless otherwise stated or clearly contradicted by context (e.g., a composition described herein as comprising a particular element should be understood as also describing a composition consisting of that element, unless otherwise stated or clearly contradicted by context).

[0284] The use of any and all examples, or exemplary language (including "for instance", "for example", "e.g.", and "such as") in the present specification is intended merely to better illuminate the invention, and does not pose a limitation on the scope of invention unless otherwise indicated.

[0285] Headings and sub-headings are used herein for convenience only, and should not be construed as limiting the invention in any way. The use of any and all examples, or exemplary language (including "for instance", "for example", "e.g.", and "such as") in the present specification is intended merely to better illuminate the invention, and does not pose a limitation on the scope of invention unless otherwise indicated. The citation and incorporation of patent documents herein is done for convenience only, and does not reflect any view of the validity, patentability and / or enforceability of such patent documents.

[0286] It should be understood that the various aspects, embodiments, implementations and features of the invention mentioned herein may be claimed separately, or in any combination.

[0287] EXPERIMENTAL

[0288] The invention will be illustrated by the following non-limiting examples.

[0289] Testing for antifouling performance

[0290] Acrylic panels of 150 mm x 200 mm were used for static immersion testing. The post-cure treatment composition was applied on top of a polysiloxane-based coat using, airless spray, Dr Blade applicator, brush or roller. After the designated duration, the remaining composition was removed using tap-water and a sponge for approximately one minute. Soap was used to remove residues of the post-cure treatment composition. Further water rinsing was used to remove any soap residues.

[0291] In cases where the polysiloxane-based coat was freshly applied, the polysiloxane-based coat was applied onto a suitable tie-coat according to the specifications of the polysiloxane-based 096

[0292] coat, and then allowed to cure for at least 24 hours to ensure that the coat was touch dry before application of the post-cure treatment composition. The polysiloxane-based coats were applied in dry film thicknesses of ranging from 100 to 400 pm. The wet film thickness (WFT) was 100 to 200 pm in most cases.

[0293] The panels were immersed in seawater at one or both test sites of Vilanova i la Geltru, located in north-eastern Spain with a salinity in the range of 37-38 parts per thousand at an average temperature in the range of 17-18 °C, and Singapore with a salinity in the range of 29-31 parts per thousand at an average temperature in the range of 29-31 °C.

[0294] Panels were inspected every 4-12 weeks and evaluated according to the following scale. One score is given for the total fouling of the types: algae and animals.

[0295] <

[0296] < <

[0297] >

[0298]

[0299] Materials

[0300] Table 1. List of materials used for the polysiloxane-based coating compositions and post-cure treatment compositions for the post-cure treatment.

[0301] &

[0302]

[0303] 096

[0304]

[0305] Table 2. Polysiloxane based coating composition (abbreviated SC).

[0306]

[0307] The polysiloxane coating (SC) was prepared by mixing all components of Part I in a pearl mill at 65°C for 30 minutes, followed by filtration through a colander. The components of Part II were mixed manually for 2 minutes. 096

[0308] The post-cure treatment composition was prepared by mixing the primary composition in a highspeed dissolver equipped with an impeller disc at 3500 rpm for at least 15 min. The secondary composition including poly(oxyalkylene)-modified silicone oil was subsequently added to the primary composition and mixed by hand.

[0309] The complete process of applying the post-cure treatment composition, waiting for the necessary contact time, and subsequently washing it off with water and / or soap and a sponge will be referred to as 'treatment'.

[0310] Antifouling performance

[0311] The post-cure treatment compositions presented below were prepared according to the prescriptions provided in this document. The post-cure treatment compositions were then applied to a freshly applied coating layer using a Dr Blade applicator with a gap-size of 300pm. After 2-96 hours the post-cure treatment compositions were removed from the substrates by gently washing by sponge with hot water and detergent for approximately one minute. Residual soap was removed by hot water. Afterwards substrates were left to dry vertically at room temperature. The treated panels were tested for antifouling performance according to the prescription provided above.

[0312] Table 3a. Various concentrations of poly(oxyalkylene) modified silicone oil. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0313]

[0314] 096

[0315]

[0316] Table 3b. Various concentrations of poly(oxyalkylene) modified silicone oil. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0317]

[0318] 096

[0319] Table 3c. Various concentrations of poly(oxyalkylene) modified silicone oil. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0320]

[0321] Table 3d. Various concentrations of poly(oxyalkylene) modified silicone oil. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0322]

[0323] 096

[0324]

[0325] Tables 3. a, b, c and d show that the post-cure treatment of a silicone paint coat with the post-cure treatment composition containing hydrophilic modified oil in various concentrations significantly improves the antifouling performance compared to both, a nontreated counterpart (3.0) (ref) and the panel treated with an oil-free formulation (3.1) after 24h.

[0326] Table 4a. Time before removal of post-cure treatment composition. Amounts are indicated by weight % based on total weight of the post-cure treatment composition.

[0327]

[0328] 096

[0329]

[0330] Table 4b. Time before removal of post-cure treatment composition. Amounts are indicated by weight % based on total weight of the post-cure treatment composition.

[0331]

[0332] 096

[0333]

[0334] Table 4c. Time before removal of post-cure treatment composition. Amounts are indicated by weight % based on total weight of the post-cure treatment composition.

[0335]

[0336] 096

[0337] Table 4d. Time before removal of post-cure treatment composition. Amounts are indicated by weight % based on total weight of the post-cure treatment composition.

[0338]

[0339] Tables 4a,b,c and d demonstrate that the antifouling performance improves with increased exposure time to the post-cure treatment composition, for a constant thickness of the applied composition in comparison with references 4.0 and 4.1.

[0340] Table 5. Time before removal of the post-cure treatment composition (200 microns WFT). Amounts are indicated by weight % based on total weight of the post-cure treatment composition. 096

[0341]

[0342] Table 5 indicates that the antifouling performance improves with increased exposure time. Comparative example 5.1, which is post-cure treated with a composition without the PEG-PDIVIS oil exhibits poor performance in Singapore. The results regarding contact time are independent of the applied WFT, provided the contact time exceeds 2 hours. 096

[0343] Table 6. Various wet film thicknesses (WFT) at different time of contact. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0344]

[0345] 096

[0346] Table 6 shows that the contact time may have influence on performance, whereas the WFT is insignificant in isopropanol formulations.

[0347] Table 7a. Various concentrations of poly(oxyalkylene) modified silicone oil in xylene. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0348]

[0349] Table 7a shows that the poly(oxyalkylene)-modified silicone oil is also infused into the polysiloxane-based coating when using a non-polar solvent such as xylene, by an improved antifouling performance. Additionally, in table 7a can be observe that a higher concentration of oils in the composition enhances infusion and antifouling performance (comparison between 7a.2 and 7a.3). Moreover an AB-type structure oil with a lower molecular weight increase oil infusion and thus improves antifouling performance (comparison between 7a.2 and 7a.5) 096

[0350] For xylene formulations of emulsions containing PEG-PDMS oil B, is observed a high degree of infusion of the poly(oxyalkylene)-modified silicone oil even at short contact times.

[0351] Table 7b. Testing of ABA structure poly(oxyalkylene) modified silicone oil in two different aliphatic hydrocarbon solvents. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0352]

[0353] 096

[0354]

[0355] Table 7b shows that a post-cure treatment with different ABA silicone oils and aliphatic solvents (non-polar) compositions according to the invention results in an improved antifouling performance. Different HLB and Molecular weights results in different performance results, however improved performance over the reference panels is consistently observed.

[0356] Table 8. Testing of AB structure poly(oxyalkylene) modified silicone oil. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition

[0357]

[0358] 096

[0359] Table 8 shows that the post-cure treatment of a silicone coating with the post-cure treatment composition containing PEG-PDMS oil C significantly improves the antifouling performance compared to both, a non-treated counterpart and the panel treated with an oil-free formulation.

[0360] Table 9. Time before removal of post-cure treatment composition. Amounts are indicated by weight % based on total weight of the post-cure treatment composition.

[0361]

[0362] Table 9 shows that the antifouling performance is significantly improved when a polysiloxane-based coating is post-cure treated with the composition compared to nontreated polysiloxane-based coating and a polysiloxane-based coating which is post-cure treated with an oil-free formulation.

[0363] Table 10a. Various wet film thicknesses (WFT) at equal time of contact before removal of the post-cure treatment composition. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition. 096

[0364]

[0365] Table 10b. Various wet film thicknesses (WFT) at equal time of contact before removal of the post-cure treatment composition. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0366]

[0367] 096

[0368]

[0369] Table 10c. Various wet film thicknesses (WFT) at equal time of contact before removal of the post-cure treatment composition. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0370]

[0371] Tables 10a, b and c show that a post-cure treatment with a composition according to the invention results in an improved antifouling performance across a range of WFT values. 096

[0372] Table Ila. Variation of the solvent for the same concentration of poly(oxyalkylene)-modified silicone oil. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition

[0373]

[0374] Table 11a shows a difference between the two types of solvents, a polar solvent and a nonpolar solvent. The poly(oxyalkylene)-modified silicone oil, WFT and contact time are constant. The results indicate that both types of solvent may be used for the purpose of post-cure treatment with a poly(oxyalkylene)-modified silicone oil in order to improve the antifouling performance. However, the polar solvent (isopropanol) may be more effective 096

[0375] than the non-polar solvent (xylene), especially when combined with a grafted poly(oxyalkylene)-modified silicone oil.

[0376] Table 11b. Variation of the type of solvent for the same concentration of poly(oxyalkylene)-modified silicone oil. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition.

[0377]

[0378] Table 11c. Variation of the type of solvent for the same concentration of poly(oxyalkylene)-modified silicone oil. Amounts are indicated by weight % based on the total weight of the post-cure treatment composition. 096

[0379]

[0380] Tables lib and c support the inclusion of two different non-polar solvents, particularly nonpolar hydrocarbon solvents. The poly(oxyalkylene)-modified silicone oil, WFT and contact time are constant. The results indicate that both types of solvent may be used for the purpose of post-cure treatment with a poly(oxyalkylene)-modified silicone oil in order to improve the antifouling performance.

[0381] Table 12. Values of D FT before and after the application and washing of different isopropanol-based emulsions.

[0382]

[0383] 096

[0384]

[0385] Table 12 verifies that the post-cure treatment is an infusion and does not involve the addition of new paint layers. DFT measurements were taken before the application of the post-cure treatment composition and after washing the surface. The measurements were conducted using a digital micrometre.

Claims

1. CLAIMS1. A method for post-cure treatment of a fouling control paint coat, said method comprising the following steps:3.a. applying a post-cure treatment composition on the surface of said fouling control paint coat;4.b. allowing the post-cure treatment composition to stay in contact with the surface of said fouling control paint coat for a period of at least 2 hours;5.wherein said post-cure treatment composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils.

2. The method according to claim 1, wherein the total amount of organic solvent constitutes between 40-99 % by weight of said post-cure treatment composition; and7.the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 1-40 % by weight of said post-cure treatment composition.

3. The method according to any of claim 1 or 2, wherein said post-cure treatment composition is allowed to stay in contact with the surface of said fouling control paint coat for a period of at least 3 hours, preferably at least 4 or 5 hours, more preferably at least 6, 7, 8, 9 or 10 hours, such as at least 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 or 24 hours.

4. The method according to any of claims 1-3, wherein said method further comprises the following step:10.c. removing excess post-cure treatment composition from the surface of said fouling control paint coat after step b,11.wherein said removal is performed by flushing the surface with water or by washing with a brush or a sponge.

5. The method according to any of claims 1-4, wherein said poly(oxyalkylene)-modified silicone oil is characterised by having an HLB value in the range of 1.5-14, such as 1.5-14, preferably 1.5-12, more preferably 1.5-10, such as 1.5-8 or 1.5-7 or 2-10.

6. The method according to any of claims 1-5, wherein said fouling control paint coat is a non-erodible paint coat, preferably a polysiloxane based paint coat.0967. The method according to any of claims 1-6, wherein said post-cure treatment composition is applied at a wet film thickness of 30-400 pm, such as 50-400 pm, e.g. 75-300 pm, or 75-200, such as about 100 pm.

8. The method according to any of claims 1-7, wherein said one or more organic solvent is selected from polar solvents, preferably an alcohol such as isopropanol.

9. The method according to any of claims 1-8, wherein said post-cure treatment composition further comprises: i) one or more hindered amine light stabilizers; and / or ii) one or more UV-absorbers.

10. The method according to claim 9, wherein said one or more hindered amine light stabilizer is present in an amount of 0.01-10% by weight of the post-cure treatment composition, such as in an amount of 0.1-5%, such as 0.1-4% or 0.1-3% or 0.1-2% or 0.1-1% by weight of the composition, or in an amount of 0.01-4%, such as 0.01-3% or 0.01-2% or 0.01-1% by weight of the composition.

11. The method according to any of claims 1-10, wherein the poly(oxyalkylene) moiety of said poly(oxyalkylene)-modified silicone oil is selected from polyoxyethylene; polyoxypropylene and / or poly(oxyethylene-co-oxypropylene), preferably polyoxyethylene.

12. The method according to any of claims 1-11, wherein said fouling control paint coat is a freshly applied coat.

13. The method according to any of claims 1-11, wherein said fouling control paint coat is an aged coat, such as a worn-out coat.

14. The method according to any of claims 1-13 wherein said post-cure treatment composition comprises one or more additives such as one or more - preferably two or more - rheological modifiers, such as thixotropic agents, thickening agents and / or anti-settling agents.

15. The method according to any of the preceding claims, wherein said post-cure treatment composition consists or consists essentially of:23.- one or more organic solvent, 09624.- one or more poly(oxyalkylene)-modified silicone oils,25.- optionally, one or more hindered amine light stabilizers, preferably being a 2, 2,6,6-tetraalkyl piperidine derivative,26.- optionally, one or more UV-absorbers, and27.- one or more, preferably two or more, rheological modifiers.

16. The method according to any of the preceding claims, wherein said post-cure treatment composition comprises or consists of:29.- at least 60 % by weight of said one or more organic solvent,30.- 1-25 % by weight of said one or more poly(oxyalkylene)-modified silicone oils,31.- 1-10 % by weight of said composition of one or more hindered amine light stabilizers, preferably being a 2,2,6,6-tetraalkyl piperidine derivative,32.- 0.1-10 % by combined weight of said composition of two or more rheological modifiers.

17. The method according to any of claims 1-15, wherein said post-cure treatment composition comprises:34.- at least 60% by weight of said one or more organic solvent, preferably wherein the one or more organic solvent comprises a hydrocarbon non-polar organic solvent,35.- 1-25% by weight of said one or more poly(oxyalkylene)-modified silicone oils,36.- 2-25% by combined weight of said composition of two or more rheological modifiers, preferably wherein the two or more rheological modifiers comprise a polyamide wax rheological modifier.

18. Use of a post-cure treatment composition in a method according to any of claims 1-17 for improving the fouling control properties of a fouling control paint coat, wherein the posttreatment composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils.

19. A fouling control paint coat, preferably a non-erodible fouling control paint coat such as a polysiloxane-based paint coat, treated by the method according to any of claims 1-17.

20. A post-cure treatment composition for a fouling control paint comprising one or more organic solvents, one or more poly(oxyalkylene)-modified silicone oils, and one or more rheological modifiers.09621. The composition according to claim 20, wherein the composition comprises two or more rheological modifiers.

22. The composition according to claim 21, wherein the two or more rheological modifiers comprise a polyamide wax rheological modifier.

23. The composition according to any of claims 20-22, wherein the one or more organic solvent comprises a hydrocarbon organic solvent, preferably a non-polar hydrocarbon organic solvent.

24. The composition according to any of claims 20-22, wherein the composition is free of a polysiloxane binder.

25. The composition according to any of claims 20-24, wherein the total amount of organic solvent constitutes between 40-99 % by weight of said post-cure treatment composition, preferably between 50-90% by weight of said post-cure treatment composition.

26. The composition according to any of claims 20-25, wherein the total amount of poly(oxyalkylene)-modified silicone oil constitutes between 1-40 % by weight of said postcure treatment composition, preferably between 5-30% by weight of said post-cure treatment composition.

27. The composition according to any of claims 20-26, wherein said poly(oxyalkylene)-modified silicone oil is characterized by having an HLB value in the range of 1.5-14, preferably 1.5-12.

28. The composition according to any of claims 20-27, wherein said poly(oxyalkylene)-modified silicone oil has the structure according to formula (I):

49.

50. wherein, 09651.each R1is independently selected from Ci-Cs-a Ikyl and aryl (e.g. phenyl (-CeHs)); each R5and R6are independently selected from R1, and the residue according to formula (i), provided that at least one R5is a residue according to formula (i);52.— R4— O — R3— 0— R253.— —In54.D- each R2is independently selected from -H, Ci-C4-al kyl, phenyl, and C1-C4- alkylcarbonyl;55.each R3is independently selected from C2-C5alkylene, arylene and C2-C5-alkylene substituted with aryl;56.each R4is selected from — (CH2)2-6-;57.x is an integer of 1-2500; and58.y is 0.

29. The composition according to any of claims 20-28, wherein the one or more rheological modifier is present in an amount of 0.1-10% by weight of the post-cure treatment composition.

30. The composition according to any of claims 20-29, wherein the composition comprises two or more rheological modifiers and the combined weight of the two or more rheological modifiers is 2 to 20% by weight of the post-cure treatment composition.

31. An article comprising a treated fouling control coating formed by the method according to any of claims 1-17, wherein the article is a marine structure or part thereof.

32. Use of a post-cure treatment composition for improving the fouling control properties of a fouling control paint, wherein the composition comprises one or more organic solvents and one or more poly(oxyalkylene)-modified silicone oils.

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