Antifouling coating composition

Abstract

The present invention addresses the problem of providing a method that can be implemented at low cost and that can sufficiently suppress propagation of algae or the like even in a submerged site where algae or the like easily propagate due to reasons such as solar radiation or the like in a substrate on which an antifouling coating film is formed. This antifouling coating composition for use in water contains (A) a hydrolyzable polymer containing a metal ester group and (B) zinc oxide having a specific surface area of 5-20 m2 / g. The content of the zinc oxide (B) is, for example, 50-150 mass% with respect to 100 mass% of the solid content of the hydrolyzable polymer (A). The antifouling coating composition for use in water may further contain an antifouling agent (C), a monocarboxylic acid compound (E) and / or a metal ester thereof. The antifouling coating film formed from the antifouling coating composition for use in water has a large ratio of coating film consumption in a bright area to a dark area that cannot be irradiated by sunlight, and has excellent standing antifouling properties and dynamic antifouling properties even in the bright area.

Description

Technical Field

[0001] The present invention relates to an antifouling coating composition, an antifouling coating film, a substrate with an antifouling coating film, a method for producing a substrate with an antifouling coating film, etc. More specifically, the present invention relates to an antifouling coating composition for underwater use containing specific components such as a hydrolyzable polymer containing a metal ester group and zinc oxide. Background Art

[0002] As a method for preventing fouling of substrates such as ships by aquatic organisms, methods for forming antifouling coatings containing hydrolyzable polymers on the surface of substrates are widely used. As such antifouling coatings, various studies have been conducted on antifouling coatings containing polymers containing metal ester groups.

[0003] For example, Patent Document 1 describes an antifouling coating composition comprising a polymer containing a metal ester group, zinc oxide, and medetomidine, wherein the zinc oxide content in the solids component is 27 to 60% by mass (claims, etc.). Patent Document 1 describes that such an antifouling coating composition can provide an antifouling coating composition capable of forming an antifouling coating film that maintains high antifouling properties for a long period of time and exhibits excellent damage resistance (paragraphs 0006, 0007, and 0018). Furthermore, according to the invention described in Citation 1, part of the reason for achieving the effect of solving the above-mentioned problems is presumed to be that "the inclusion of a hydrolyzable polymer (A) having a metal ester group imparts suitable water resistance and surface renewal properties in water to the antifouling coating film, and further, the inclusion of specific amounts of zinc oxide (B) and medetomidine (C) results in an antifouling coating film that maintains antifouling properties for a longer period of time and exhibits excellent damage resistance due to the interaction within the resulting antifouling coating film" (paragraph 0021). It is also described that "the above-mentioned effect is not a simple combination of the effects of the hydrolyzable polymer (A), zinc oxide (B), and medetomidine (C), but rather a synergistic effect produced by their combined use" (paragraph 0057). It should be noted that Patent Document 1 does not specifically mention the specific surface area or other properties of the zinc oxide used.

[0004] On the other hand, antifouling coating compositions that utilize photocatalytic activity to exert antifouling properties have also been proposed. For example, Patent Document 2 describes an underwater antifouling coating composition containing a metal oxide powder having photocatalytic activity and a binder (claims, etc.). The invention states that by incorporating the metal oxide powder having photocatalytic activity, a coating composition having long-term antifouling properties, excellent safety, hygiene, and environmental protection, and less prone to forming a skeleton structure can be obtained. In this invention, a large amount of photocatalyst powder near the surface of the formed coating film, which absorbs sunlight, oxidizes or reduces the binder near its periphery, decomposing it and causing it to dissolve or fall off in seawater. The photocatalyst powder thus exposed on the surface of the coating film has a bactericidal effect, thereby preventing the attachment of aquatic organisms (paragraphs 0005, 0006, and 0019). Patent Document 2 lists anatase-type titanium oxide (TiO2), zinc oxide (ZnO), vanadium oxide (V2O5), tungsten oxide (WO3), and rubidium oxide (RuO2) as examples of metal oxide powders with photocatalytic activity. The patent also states that "anatase-type titanium oxide, which has excellent decomposition capabilities for organic compounds, is particularly preferred." Furthermore, the patent states that, in order to increase the surface area and photocatalytic activity, the average particle size of the photocatalyst powder is suitably 0.001 to 0.8 μm, preferably 0.003 to 0.05 μm (paragraph 0007). It should be noted that, while "seawater-insoluble resins" (vinyl resins, polyester resins, etc.) and "hydrolyzable resins" are exemplified as "binders" in Patent Document 2 (paragraph 0008), the patent only discloses the use of "seawater-insoluble resins" (acrylic resins not containing metal ester groups) in combination with "anatase-type titanium oxide" (paragraph 0015).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: WO2018 / 003135

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 10-204335 Summary of the Invention

[0009] Problems to be solved by the invention

[0010] On substrates such as ships, where antifouling coatings are formed (and on which antifouling coating compositions are applied), algae and, consequently, marine organisms that use them as a foothold, are prone to multiplying in areas exposed to sunlight. Surface-washable antifouling coatings formed from antifouling coating compositions containing hydrolyzable polymers containing metal ester groups can improve antifouling properties such as algae resistance by designing them to have a high degree of film wear (for example, by incorporating highly hydrophilic raw materials). However, it is often impossible to determine in advance whether the areas to be coated are prone to algae growth due to factors such as exposure to sunlight. Furthermore, on a single substrate such as a ship, applying an antifouling coating composition with a relatively high degree of film wear to areas prone to algae growth and an antifouling coating composition with a relatively low degree of film wear to other areas makes it difficult to apply different antifouling coating compositions separately to specific areas.

[0011] The present invention aims to provide a method that can be implemented at low cost and that can sufficiently suppress the growth of algae and the like even in flooded areas where algae and the like are likely to grow due to exposure to sunlight, etc., on a substrate on which an antifouling coating film is formed (on which an antifouling coating composition is applied).

[0012] Methods used to solve problems

[0013] The present inventors have discovered that an antifouling coating film formed from an antifouling coating composition containing a hydrolyzable polymer containing a metal ester group and zinc oxide having a specific surface area within a specific range exhibits increased wear of the coating film at flooded areas exposed to sunlight, thereby improving antifouling properties. This finding solves the aforementioned problems.

[0014] That is, the present invention includes at least the following matters. [1]

[0016] An antifouling coating composition for use in water, comprising a hydrolyzable polymer (A) containing a metal ester group and a polymer having a specific surface area of ​​5 to 20 m 2 / g of zinc oxide (B). [2]

[0018] The underwater antifouling coating composition according to item 1, wherein the content of the zinc oxide (B) is 50 to 150% by mass relative to 100% by mass of the solid content of the hydrolyzable polymer (A). [3]

[0020] The underwater antifouling coating composition according to Item 1 or 2, further comprising an antifouling agent (C). [4]

[0022] The underwater antifouling coating composition according to any one of items 1 to 3, further comprising a monocarboxylic acid compound (E) and / or a metal ester thereof. [5]

[0024] An antifouling coating film formed from the underwater antifouling coating composition according to any one of items 1 to 4. [6]

[0026] A substrate with an antifouling coating film, comprising a substrate and the antifouling coating film according to item 5. [7]

[0028] A method for producing a substrate with an antifouling coating film, comprising: a step (1) of applying the underwater antifouling coating composition according to any one of items 1 to 4 onto a substrate or impregnating the substrate to obtain a coated body or an impregnated body; and a step (2) of drying the coated body or the impregnated body. [8]

[0030] The method for producing a substrate with an antifouling coating according to item 7, wherein the substrate is the bottom of a ship, and in the step (1), the underwater antifouling coating composition having the same composition is applied more to a portion easily exposed to sunlight and less to a portion less easily exposed to sunlight, and the film thickness of the antifouling coating formed after the step (2) is given a gradient. [9]

[0032] An antifouling coating film comprising a hydrolyzable polymer containing a metal ester group and zinc oxide, wherein the light-to-dark rubbed film thickness ratio measured by the following method is 1.5 or more,

[0033] (Light and dark grinding film thickness ratio)

[0034] A test plate formed with an antifouling coating is fixed to the surface of a rotating drum. The drum is rotated at a speed of 10 knots in a water tank filled with seawater, which is replaced at a constant rate, in a room. The test plate is placed in a location exposed to sunlight (bright area) and a location shielded from sunlight (dark area) for 3 months. The ratio of the coating film consumption in the bright area to the coating film consumption in the dark area (film thickness at the beginning - film thickness after 3 months) is measured.

[10]

[0036] A substrate with an antifouling coating film, comprising a substrate and the antifouling coating film according to item 9.

[0037] Effects of the Invention

[0038] The antifouling coating formed from the antifouling coating composition of the present invention increases the rate of coating consumption in submerged areas of the substrate where algae and other organisms are likely to grow due to exposure to sunlight, thereby effectively suppressing the growth of algae and other organisms. On the other hand, in areas less exposed to sunlight and where the coating has not been consumed, the remaining coating becomes thicker, allowing for a reduction in the amount of coating applied during the next recoating, resulting in an economic advantage. This effect is achieved by applying a single antifouling coating composition to the entire submerged area of ​​the substrate, eliminating the need to modify the design of the antifouling coating composition applied to each area of ​​the substrate based on exposure to sunlight. The antifouling properties (static antifouling performance and dynamic antifouling performance) of the present invention are based on the synergistic effect produced by combining zinc oxide having a specific surface area that meets specified requirements with a hydrolyzable polymer containing a metal ester group, and are not believed to be solely based on the "photocatalytic activity" described in Patent Document 2. DETAILED DESCRIPTION

[0039] In this specification, “(meth)acrylic acid” means “acrylic acid or methacrylic acid” or “acrylic acid and methacrylic acid” according to the context, and “(meth)acrylate” means “acrylate or methacrylate” or “acrylate and methacrylate” according to the context.

[0040] The upper limit and lower limit values ​​(for example, regarding the content of a component) described in this specification can be arbitrarily combined to set a numerical range.

[0041] In this specification (especially in the Examples), unless otherwise specified, "parts" as a unit following a numerical value means "parts by mass." Furthermore, "parts by mass" of a substance relative to 100 parts by mass of a reference substance has the same meaning as "% by mass" of a substance relative to 100% by mass of a reference substance.

[0042] -Antifouling coating composition for underwater use-

[0043] The underwater antifouling coating composition of the present invention comprises a hydrolyzable polymer (A) containing a metal ester group (also referred to as "hydrolyzable polymer (A)" or "component (A)" in this specification) and a polymer having a specific surface area of ​​5 to 20 m 2 / g of zinc oxide (B) (in this specification, it may also be simply referred to as "zinc oxide (B)" or "component (B)").

[0044] <Hydrolyzable polymer (A)>

[0045] The hydrolyzable polymer (A) comprises a structural unit derived from a metal ester group-containing monomer (a1) (also referred to herein as "monomer (a1)") and / or a structural unit derived from a metal ester group-containing monomer (a2) (also referred to herein as "monomer (a2)"). Any one hydrolyzable polymer (A) may be used, or two or more structural units derived from monomer (a1) and / or monomer (a2) may be used, each having different structures, ratios, and the like.

[0046] Metal ester group-containing monomer (a1)

[0047] The metal ester group-containing monomer (a1) is a monomer represented by the following formula (1): The monomer (a1) may be any one kind or two or more kinds.

[0048]

[0049] In formula (1), R 11 Each independently represents a monovalent group containing a terminal ethylenically unsaturated group (CH2=C<), and M represents a copper atom or a zinc atom.

[0050] R 11 The number of carbon atoms of the terminal ethylenically unsaturated group is preferably 2 to 50, more preferably 2 to 30, further preferably 2 to 10, and particularly preferably 2 to 6.

[0051] R 11 The ethylenically unsaturated group may be contained in addition to the terminal, but it is more preferable to contain the ethylenically unsaturated group only at the terminal.

[0052] R 11Preferably, it is an organic group containing a terminal ethylenically unsaturated group (referred to as "terminal ethylenically unsaturated organic group" in this specification). Examples of the terminal ethylenically unsaturated organic group include unsaturated aliphatic hydrocarbon groups whose structure may be partially substituted with an ester bond, an amide bond, or an ether bond. Specific examples of such terminal ethylenically unsaturated organic groups include: groups obtained by removing a carboxyl group from an aliphatic unsaturated monocarboxylic acid containing a terminal ethylenically unsaturated group, such as acrylic acid (also known as 2-acrylic acid), methacrylic acid (also known as 2-methyl-2-acrylic acid), 3-butenoic acid, 4-pentenoic acid, 10-undecenoic acid, (meth)acryloyloxyalkylcarboxylic acid [e.g., 3-(meth)acryloyloxypropionic acid, 3-(meth)acryloyloxy-2-methylpropionic acid]; and groups obtained by removing one carboxyl group from an aliphatic unsaturated dicarboxylic acid having a terminal ethylenically unsaturated group, such as itaconic acid. As the terminal ethylenically unsaturated organic group, a group obtained by removing a carboxyl group from an aliphatic unsaturated monocarboxylic acid containing a terminal ethylenically unsaturated group is more preferred, a group obtained by removing a carboxyl group from acrylic acid, methacrylic acid or (meth)acryloyloxyalkylcarboxylic acid is further preferred, and a group obtained by removing a carboxyl group from acrylic acid or methacrylic acid is particularly preferred.

[0053] As the monomer (a1), a monomer represented by the following formula (1') is preferred (also referred to as "monomer (a1')" in this specification). Monomer (a1') corresponds to two R 11 The terminal ethylenically unsaturated organic groups are all groups obtained by removing a carboxyl group from acrylic acid or methacrylic acid.

[0054]

[0055] In formula (1'), R 12 Each independently represents a hydrogen atom or a methyl group, and M represents a copper atom or a zinc atom.

[0056] Examples of monomer (a1) include zinc diacrylate, zinc dimethacrylate, zinc acrylate and methacrylate, zinc bis(3-acryloyloxypropionate), zinc bis(3-methacryloyloxypropionate), zinc bis(3-(meth)acryloyloxy-2-methylpropionate), copper diacrylate, copper dimethacrylate, copper acrylate and methacrylate, copper bis(3-acryloyloxypropionate), copper bis(3-methacryloyloxypropionate), and copper bis(3-(meth)acryloyloxy-2-methylpropionate). Among these, zinc diacrylate, zinc dimethacrylate, and zinc acrylate and methacrylate are preferred because they can easily produce an antifouling coating film having sufficient antifouling properties. Note that zinc diacrylate, zinc dimethacrylate, zinc acrylate and methacrylate, copper diacrylate, copper dimethacrylate, and copper acrylate and methacrylate are monomers (a1′).

[0057] Metal ester group-containing monomer (a2)

[0058] The metal ester group-containing monomer (a2) is a monomer represented by the following formula (2): The monomer (a2) may be any one kind or two or more kinds.

[0059]

[0060] In formula (2), R 21 represents a monovalent group containing a terminal ethylenically unsaturated group (CH2=C<), R 22 represents a monovalent organic group having 1 to 30 carbon atoms and not containing a terminal ethylenically unsaturated group, and M represents a copper atom or a zinc atom.

[0061] About R 21 For technical matters related to the terminal ethylenically unsaturated group of R, refer directly to the description of R in the relationship with formula (1) in this specification. 11 Technical matters related to terminal ethylenically unsaturated groups.

[0062] As R 22 Examples of such organic groups include aliphatic hydrocarbon groups having 1 to 30 carbon atoms, alicyclic hydrocarbon groups having 3 to 30 carbon atoms, and aromatic hydrocarbon groups having 6 to 30 carbon atoms, which do not contain a terminal ethylenically unsaturated group (referred to herein as "non-terminal ethylenically unsaturated organic groups"). The non-terminal ethylenically unsaturated organic group may further contain a substituent (e.g., a hydrogen group).

[0063] The aliphatic hydrocarbon group in the non-terminal ethylenically unsaturated organic group may be either linear or branched, and may be either a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group (as long as it does not contain a terminal ethylenically unsaturated group). The aliphatic hydrocarbon group has 1 to 30 carbon atoms, preferably 1 to 28, more preferably 1 to 26, and even more preferably 1 to 24. The aliphatic hydrocarbon group may be substituted with an alicyclic hydrocarbon group or an aromatic hydrocarbon group.

[0064] The alicyclic hydrocarbon group in the non-terminal ethylenically unsaturated organic group may be a saturated alicyclic hydrocarbon group or an unsaturated alicyclic hydrocarbon group. The alicyclic hydrocarbon group has 3 to 30 carbon atoms, preferably 4 to 20 carbon atoms, more preferably 5 to 16 carbon atoms, and even more preferably 6 to 12 carbon atoms. The alicyclic hydrocarbon group may be substituted with an aliphatic hydrocarbon group or an aromatic hydrocarbon group.

[0065] The number of carbon atoms in the aromatic hydrocarbon group in the non-terminal ethylenically unsaturated organic group is 6 to 30, preferably 6 to 24, more preferably 6 to 18, and even more preferably 6 to 10. The aromatic hydrocarbon group may be substituted with an aliphatic hydrocarbon group or an alicyclic hydrocarbon group.

[0066] R 22 Preferred are organic acid residues derived from monobasic acids. Specific examples include groups obtained by removing a carboxyl group from organic acids such as versatic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, linoleic acid, linolenic acid, abietic acid, neoabietic acid, pimaric acid, dehydroabietic acid, 12-hydroxystearic acid, and cycloalkane acid. Of these, groups obtained by removing a carboxyl group from abietic acid, versatic acid, or cycloalkane acid are preferred, and groups obtained by removing a carboxyl group from abietic acid or versatic acid are more preferred. Versatic acid is a general term for a mixture of heavily branched carboxylic acids having 9 to 11 carbon atoms, primarily 10.

[0067] As the monomer (a2), a monomer represented by the following formula (2') is preferred (also referred to as "monomer (a2')" in this specification). Monomer (a2') corresponds to R in monomer (2). 22 The terminal ethylenically unsaturated organic group is a monomer obtained by removing a carboxyl group from acrylic acid or methacrylic acid.

[0068]

[0069] In formula (2'), R 23 represents a hydrogen atom or a methyl group, R 24 and R in formula (2) 22 The meanings are the same, and M represents a copper atom or a zinc atom.

[0070] Examples of monomer (a2) include rosin zinc 3-(meth)acryloyloxypropionate, zinc versatate 3-(meth)acryloyloxypropionate, rosin zinc (meth)acrylate, zinc versatate (meth)acrylate, zinc naphthenate, zinc (meth)acrylate, rosin copper 3-(meth)acryloyloxypropionate, copper versatate 3-(meth)acryloyloxypropionate, rosin copper (meth)acrylate, copper versatate (meth)acrylate, and copper naphthenate. Note that rosin zinc (meth)acrylate, zinc versatate (meth)acrylate, zinc naphthenate, rosin copper (meth)acrylate, copper versatate (meth)acrylate, and copper naphthenate are monomers (a2′).

[0071] Comonomer

[0072] The hydrolyzable polymer (A) may further contain monomers other than monomer (a1) and monomer (a2) that are copolymerizable with monomer (a1) and / or monomer (a2), as needed. Examples of such optional monomers include monomers that do not contain a metal ester group and have an ethylenically unsaturated group, for example, an organosiloxane block monomer (a3) ​​(sometimes referred to as "monomer (a3)" in this specification); a (meth)acrylate or its ester (a4) (sometimes referred to as "monomer (a4)" in this specification); and a vinyl compound (a5) (sometimes referred to as "monomer (a5)" in this specification).

[0073] Monomer (a3)

[0074] The monomer (a3), ie, the organosiloxane block-containing monomer (a3), is a monomer represented by the following formula (3). The monomer (a3) ​​may be any one kind or two or more kinds.

[0075]

[0076] In formula (3), R 31 、R 32 and R 33 Each independently represents a monovalent hydrocarbon group, X each independently represents a (meth)acryloyloxyalkyl group or a mercaptoalkyl group, m is 1 or greater, n is 0 or greater, p and q each independently represent 0 or 1, and n+p+q is 1 or greater.

[0077] As R 31 、R 32 and R 33 The hydrocarbon group includes, for example, linear, branched or cyclic alkyl groups and aryl groups. The number of carbon atoms in the alkyl group is preferably 1 to 12, more preferably 1 to 8, and even more preferably 1 to 4. The number of carbon atoms in the aryl group is preferably 6 to 14, more preferably 6 to 10. From the viewpoint of ease of polymerization, R 31 、R 32 and R 33 Each is independently an alkyl group such as methyl or butyl.

[0078] Examples of X include (meth)acryloyloxyalkyl groups such as (meth)acryloyloxyethyl, (meth)acryloyloxypropyl, and (meth)acryloyloxybutyl; and mercaptoalkyl groups such as mercaptomethyl, mercaptoethyl, mercaptopropyl, and mercaptobutyl. From the perspective of uniform polymerization, X is preferably a (meth)acryloyloxyalkyl group, and from the perspective of reducing the viscosity of the hydrolyzable polymer (A) and facilitating handling, a mercaptoalkyl group is preferably used.

[0079] m and n represent (SiR 32 2O), (SiXR 33The average added mole number of m+n is preferably 2 or more. That is, the organosiloxane block-containing monomer (a3) ​​is preferably a polyorganosiloxane block-containing monomer.

[0080] It should be noted that in this specification, as shown in formula (3), when two or more different repeating units are listed in parallel between [], it means that these repeating units can be repeated in any order of random, alternating or block. That is, for example, in the case of the formula -[Y3-Z3]- (wherein Y and Z each represent a repeating unit), it can be a random shape such as -YYZYZZ-, an alternating shape such as -YZYZYZ-, or a block shape such as -YYYZZZ- or -ZZZYYY-.

[0081] A first embodiment of the monomer (a3) ​​includes a monomer (a31) in which n is 0, p is 1, and q is 0. A hydrolyzable polymer (A) preferably contains a structural unit derived from such a monomer (a31), because, for example, the antifouling coating composition readily forms an antifouling coating film having excellent antifouling properties. From the perspective of ease of polymerization, m in the monomer (a31) is preferably 3 or greater, more preferably 5 or greater, and preferably 200 or less, more preferably 70 or less.

[0082] As the monomer (a31), for example, commercial products "FM-0711" (one-terminal methacryloxyalkyl-modified organopolysiloxane, number average molecular weight: 1000), "FM-0721" (one-terminal methacryloxyalkyl-modified organopolysiloxane, number average molecular weight: 5000), and "FM-0725" (one-terminal methacryloxyalkyl-modified organopolysiloxane, number average molecular weight: 10000) manufactured by JNC Corporation can be used; Commercially available products manufactured by Koshi Chemical Industry Co., Ltd. include "X-22-174ASX" (single-end methacryloxyalkyl-modified organic polysiloxane, functional group equivalent: 900 g / mol), "KF-2012" (single-end methacryloxyalkyl-modified organic polysiloxane, functional group equivalent: 4600 g / mol), and X-22-2426 (single-end methacryloxyalkyl-modified organic polysiloxane, functional group equivalent: 12000 g / mol).

[0083] A second embodiment of monomer (a3) ​​includes a monomer (a32) in which n is 0 and p and q are 1. When the hydrolyzable polymer (A) contains a structural unit derived from such a monomer (a32), it is preferred because, for example, the antifouling coating composition can be easily repaired, that is, an antifouling coating film with excellent adhesion to an old antifouling coating film after use (after immersion in seawater) can be formed. From the viewpoint of ease of polymerization, m in monomer (a32) is preferably 3 or more, more preferably 5 or more, and preferably 200 or less, more preferably 70 or less.

[0084] As the monomer (a32), for example, commercial products “FM-7711” (organopolysiloxane modified with methacryloxyalkyl groups at both ends, number average molecular weight: 1000), “FM-7721” (organopolysiloxane modified with methacryloxyalkyl groups at both ends, number average molecular weight: 5000), and “FM-7725” (organopolysiloxane modified with methacryloxyalkyl groups at both ends, number average molecular weight: 10000) manufactured by JNC Corporation; and commercial products “X-22-164” (organopolysiloxane modified with methacryloxyalkyl groups at both ends, functional group equivalent: 190 g / mol), and “X-22-164AS” (organopolysiloxane modified with methacryloxyalkyl groups at both ends, functional group equivalent: 190 g / mol) manufactured by Shin-Etsu Chemical Co., Ltd. , functional group equivalent: 450g / mol), "X-22-164A" (methacryloyloxyalkyl modified organic polysiloxane at both ends, functional group equivalent: 860g / mol), "X-22-164B" (methacryloyloxyalkyl modified organic polysiloxane at both ends, functional group equivalent: 1630g / mol), "X-22-164C" (methacryloyloxyalkyl modified organic polysiloxane at both ends, functional group equivalent: 2370g / mol), "X-22-164E" (methacryloyloxyalkyl modified organic polysiloxane at both ends, functional group equivalent: 3900g / mol), "X-22-167B" (mercaptoalkyl modified organic polysiloxane at both ends, functional group equivalent: 1670g / mol), etc.

[0085] A third embodiment of monomer (a3) ​​includes monomer (a33) in which n is 1 or greater. It is preferred that the hydrolyzable polymer (A) contain a structural unit derived from such a monomer (a33), for example, because the viscosity of the antifouling coating composition decreases, tending to facilitate handling. In monomer (a33), m is preferably 50 to 1000, and n is preferably 1 to 30.

[0086] As monomer (a33), for example, commercially available products "KF-2001" (side chain mercaptoalkyl-modified organopolysiloxane, functional group equivalent: 1900 g / mol) and "KF-2004" (side chain mercaptoalkyl-modified organopolysiloxane, functional group equivalent: 30000 g / mol) manufactured by Shin-Etsu Chemical Co., Ltd. can be used.

[0087] Monomer (a4)

[0088] The monomer (a4), that is, a (meth)acrylate or an ester thereof (a4), is a compound represented by the following formula (4): The monomer (a4) may be one kind or two or more kinds.

[0089]

[0090] In formula (4), R 41 represents a monovalent group containing an ethylenically unsaturated group, R 42 represents a hydrogen atom, an alkyl group, an aryl group, an alkoxyalkyl group, a hydroxyalkyl group or a glycidyl group.

[0091] As a first embodiment of the monomer (a4), R 42 A monomer (a41) containing a hydrogen atom, such as (meth)acrylic acid. When the hydrolyzable polymer (A) contains such a monomer (a41), the resulting antifouling coating composition tends to have excellent adhesion to an old antifouling coating film after use (after immersion in seawater), low viscosity, and excellent coating workability, and the formed antifouling coating film tends to have a high degree of film wear.

[0092] As a second embodiment of the monomer (a4), R 42 A monomer (a42) which is an alkyl group or an aryl group. 42 The alkyl group may have any structure of linear, branched, or cyclic, and the number of carbon atoms is preferably 1 to 20, more preferably 1 to 12, and even more preferably 1 to 6. When the hydrolyzable polymer (A) contains such a monomer (a42), the antifouling coating film formed from the resulting antifouling coating composition tends to be able to suppress the coating film consumption to an appropriate renewal rate without significantly impairing the antifouling properties, and tends to also have excellent scratch resistance and / or crack resistance.

[0093] Specific examples of monomer (a42) include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 3,5,5-trimethylhexyl (meth)acrylate, lauryl (meth)acrylate, hexadecyl (meth)acrylate, stearyl (meth)acrylate, phenyl (meth)acrylate, and benzyl (meth)acrylate. For example, at least one selected from the group consisting of methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, and cyclohexyl (meth)acrylate is preferably used as monomer (a42).

[0094] As a third embodiment of the monomer (a4), R 42 A monomer (a43) which is an alkoxyalkyl group. 42 The alkoxyalkyl group may have any structure of linear, branched, or cyclic, and the number of carbon atoms (the total number of carbon atoms contained in the alkyl group in the alkoxy group and the number of carbon atoms contained in the alkyl group) is preferably 1 to 20, more preferably 1 to 12, and even more preferably 1 to 6. When the hydrolyzable polymer (A) contains such a monomer (a43), the antifouling coating film formed from the resulting antifouling coating composition tends to maintain a suitable coating film consumption rate for a long period of time.

[0095] Specific examples of monomer (a43) include 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, 4-methoxybutyl (meth)acrylate, 3-methoxy-n-propyl (meth)acrylate, 2-propoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, isobutoxybutyl diglycol (meth)acrylate, 2-phenoxyethyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethoxypolyethylene glycol (meth)acrylate, butoxypolyethylene glycol (meth)acrylate, and phenoxypolyethylene glycol (meth)acrylate. For example, 2-methoxyethyl (meth)acrylate is preferably used as monomer (a43).

[0096] As a fourth embodiment of the monomer (a4), R 42 A monomer (a44) having a hydroxyalkyl group. 42The hydroxyalkyl group may have any structure of linear, branched, or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 12, and even more preferably 1 to 6. When the hydrolyzable polymer (A) contains such a monomer (a44), the antifouling coating film formed from the resulting antifouling coating composition tends to have a high degree of coating film consumption.

[0097] Specific examples of the monomer (a44) include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 2-hydroxy-3-phenoxypropyl (meth)acrylate.

[0098] As a fifth embodiment of the monomer (a4), R 42 The monomer (a45) is a glycidyl group, for example, glycidyl (meth)acrylate. When the hydrolyzable polymer (A) contains such a monomer (a44), the antifouling coating film formed from the obtained antifouling coating composition tends to have a high degree of coating film consumption.

[0099] The hydrolyzable polymer (A) preferably contains monomer (a42) and / or monomer (a43) among the above-mentioned monomers (a4), from the viewpoint that the antifouling coating film formed from the obtained antifouling coating composition can appropriately adjust the degree of coating film consumption and tends to have excellent scratch resistance and / or crack resistance.

[0100] Monomer (a5)

[0101] Examples of the monomer (a5), i.e., vinyl compound, include styrene, α-methylstyrene, vinyl acetate, vinyl benzoate, vinyltoluene, acrylonitrile, vinylpyridine, vinylpyrrolidone, and vinyl chloride. The monomer (a5) may be any one or two or more.

[0102] Ratio of structural units

[0103] The types and ratios of the structural units derived from the monomer (a1) and / or monomer (a2) contained in the hydrolyzable polymer (A) and other monomers used as needed can be appropriately adjusted in consideration of the effects of the present invention and other technical matters.

[0104] For example, the ratio of the structural unit derived from the monomer (a1) and / or the structural unit derived from the monomer (a2) is preferably 5% by mass or more, more preferably 7% by mass or more, and even more preferably 9% by mass or more, and is preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass or less, relative to 100% by mass of all the structural units in the hydrolyzable polymer (A).

[0105] The hydrolyzable polymer (A) preferably contains at least a structural unit derived from a (meth)acrylate or an ester thereof (a4) in addition to the structural unit derived from the monomer (a1) and / or the structural unit derived from the monomer (a2), and may further contain a structural unit derived from an organosiloxane-containing block monomer (a3).

[0106] When the hydrolyzable polymer (A) contains a structural unit derived from the organosiloxane-containing block monomer (a3), the ratio thereof is preferably 5% by mass or more, more preferably 8% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, relative to 100% by mass of all the structural units in the hydrolyzable polymer (A).

[0107] When the hydrolyzable polymer (A) contains a structural unit derived from a (meth)acrylate or its ester (a4), the ratio thereof is preferably 3% by mass or more, more preferably 5% by mass or more, and is preferably 95% by mass or less, more preferably 80% by mass or less, and particularly preferably 70% by mass or less, relative to 100% by mass of all the structural units in the hydrolyzable polymer (A).

[0108] When the hydrolyzable polymer (A) contains a structural unit derived from a (meth)acrylate or its ester (a4), the ratio thereof is preferably 3% by mass or more, more preferably 5% by mass or more, and is preferably 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less, relative to 100% by mass of all the structural units in the hydrolyzable polymer (A).

[0109] It should be noted that the ratio of each structural unit in the hydrolyzable polymer (A) can be measured by conventional methods such as nuclear magnetic resonance spectroscopy (NMR) and gas chromatography-mass spectrometry (GC-MS), or can be calculated from the amount of each monomer used in synthesizing the hydrolyzable polymer (A). In addition, the total structural units in the hydrolyzable polymer (A) do not include structural units derived from polymerization initiators and chain transfer agents.

[0110] The number average molecular weight (Mn) and weight average molecular weight (Mw) of the hydrolyzable polymer (A) can be appropriately adjusted so as to achieve the desired effect of the present invention, taking into account the viscosity and storage stability of the resulting antifouling coating composition, the degree of film consumption (dissolution rate, renewal) of the resulting antifouling coating film, and the like. The Mn of the hydrolyzable polymer (A) is preferably 500 or more, more preferably 700 or more, and is preferably 100,000 or less, and more preferably 50,000 or less. The Mw of the hydrolyzable polymer (A) is preferably 1,000 or more, more preferably 1,200 or more, and particularly preferably 1,500 or more, and is preferably 150,000 or less, more preferably 10,000 or less, and particularly preferably 7,000 or less.

[0111] It should be noted that Mn and Mw can be determined by measuring by gel permeation chromatography according to a conventional method and converting them to standard polystyrene. For more specific measurement methods and conditions of Mn and Mw, please refer to the Examples described below.

[0112] Content of ingredient (A)

[0113] The content of the hydrolyzable polymer (A) can be appropriately adjusted according to the type and properties of the component so as to achieve the desired effect of the present invention, and in consideration of the coating workability of the resulting underwater antifouling coating composition and other technical matters. The content of the hydrolyzable polymer (A) is, for example, preferably 10% by mass or more, more preferably 15% by mass or more, and preferably 40% by mass or less, more preferably 35% by mass or less, relative to 100% by mass of the solid content of the underwater antifouling coating composition.

[0114] In this specification, the "solid content" of the underwater antifouling coating composition of the present invention or the components contained therein (e.g., the solution containing component (A), the oxidized polyethylene wax as the anti-sagging / anti-settling agent (H), the fatty acid amide wax, etc.) refers to the content after removing the volatile components contained as solvents in the underwater antifouling coating composition of the present invention or the components. This solid content can be calculated according to conventional methods as the ratio of the mass of the antifouling coating composition of the present invention or the components thereof dried in a hot air dryer at 108°C for 3 hours to the mass of the underwater antifouling coating composition of the present invention or the components thereof. More specifically, according to JIS K 5601-1-2:2008, 1±0.1 g of the object to be measured is weighed into a flat-bottomed dish, uniformly spread across the bottom surface with a wire of known mass, and dried at 108°C at 1 atmosphere for 3 hours. The mass of the wire is then subtracted from the resulting heated residue to calculate the mass percentage.

[0115] It should be noted that, with respect to the product of each component, when a numerical value in terms of solid content is indicated on a label, catalog, or the like, that numerical value may be regarded as the solid content of that component. Furthermore, when the composition ratio (the type and amount of each component and the solid content of each component) of the antifouling coating composition of the present invention is known by the above-mentioned measurement method, the numerical value calculated based on that composition ratio may be regarded as the solid content of the antifouling coating composition of the present invention.

[0116] <Zinc oxide (B)>

[0117] Zinc oxide (B) has a specific surface area within a specific range, specifically a specific surface area of ​​5 to 20 m 2 / g, preferably 7 to 15m 2 / g of zinc oxide. The specific surface area of ​​zinc oxide in the present invention is a value measured by a gas adsorption method (BET one-point method). This specific surface area can be measured using "FlowSorb II 2300" manufactured by Shimadzu Corporation as shown in Table 3 below.

[0118] Specific surface area is 5 to 20 m 2 Zinc oxide (B) of 10.2 m / g can be obtained, for example, from "Zincox super F-1" (manufactured by Shiraishi Techno Co., Ltd., with a specific surface area of ​​10.2 m 2 / g), "ABZ-10" (manufactured by Sakai Chemical Industry Co., Ltd., with a specific surface area of ​​9.2 m 2 / g) and other commodities.

[0119] Content of component (B)

[0120] The content of zinc oxide (B) can be appropriately adjusted to achieve the desired effect of the present invention, depending on the type and properties of the component, and in consideration of the coating workability of the resulting underwater antifouling coating composition and other technical matters. The content of zinc oxide (B) is, for example, preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 20% by mass or less, and preferably 70% by mass or less, more preferably 50% by mass or less, and even more preferably 45% or less, relative to 100% by mass of the solid content of the underwater antifouling coating composition. Furthermore, the content of zinc oxide (B) is preferably 50% by mass or more, more preferably 70% by mass or less, and preferably 150% by mass or less, and even more preferably 125% by mass or less, relative to 100% by mass of the solid content of the hydrolyzable polymer (A).

[0121] Optional ingredients

[0122] The underwater antifouling coating composition of the present invention may further contain components other than the hydrolyzable polymer (A) and zinc oxide (B) as needed. Examples of such optional components include an antifouling agent (C), a pigment (D), a monocarboxylic acid compound (E) and / or its metal ester, a defoaming agent (F), a solvent (G), an anti-sagging agent / anti-settling agent (H), a plasticizer (I), and a binder component (J) (sometimes referred to as components (C) to (J) in this specification). These optional components are not essential for achieving the effects of the present invention, but may be components that are naturally required or commonly used for the implementation (manufacturing, use, etc.) of the underwater antifouling coating composition, components that facilitate or enhance the effects of the present invention, or components that are used to achieve effects other than those of the present invention. Furthermore, other components used in conventional antifouling coating compositions may be used as components of the underwater antifouling coating composition of the present invention as desired.

[0123] <Antifouling agent (C)>

[0124] The underwater antifouling coating composition of the present invention can exhibit a certain level of excellent antifouling performance even without containing the antifouling agent (C), but may contain the antifouling agent (C) as needed. Examples of the antifouling agent (C) include cuprous oxide, metal pyrithione (e.g., copper pyrithione, zinc pyrithione), (+ / -)-4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole (also known as medetomidine), 4-bromo-2-(4-chlorophenyl)-5-(trifluoromethyl)-1H-pyrrole-3-carbonitrile (also known as bromopyrrolecarbonitrile), 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (also known as DCOIT), pyridinetriphenylborane, 4-isopropylpyridinediphenylmethylborane, N,N-dimethyl-N'-(3,4-dichlorophenyl)urea (also known as diuron), N-(2,4,6-trichlorophenyl)maleimide, 2,4,5,6-tetrachloroisophthalonitrile, 2-methylthio-4-tert-butylpyridine Butylamino-6-cyclopropylamino-1,3,5-triazine (also known as Cybutryne), zinc bisdimethyldithiocarbamoylethylenebisdithiocarbamate (also known as Polycarbamate), chloromethyl n-octyl disulfide, N,N'-dimethyl-N'-phenyl-(N-fluorodichloromethylthio)sulfonamide (also known as Dichlofluanid), tetraalkylthiuram disulfide (also known as TMTD), zinc dimethyldithiocarbamate (also known as Ziram), zinc ethylenebisdithiocarbamate, 2,3-dichloro-N-(2',6'-dimethylphenyl)maleimide, 2,3-dichloro-N-(2'-ethyl-6'-methylphenyl)maleimide, etc. The antifouling agent (C) may be used alone or in combination of two or more. For example, cuprous oxide, metal pyrithione, medetomidine, bromopyrrolecarbonitrile, and DCOIT are preferred as the antifouling agent (C).

[0125] When the antifouling coating composition for underwater use of the present invention contains an antifouling agent (C), the content thereof can be appropriately adjusted depending on the purpose (antifouling performance), the type of the component, etc. For example, with respect to 100% by mass of the solid content of the composition, the content of cuprous oxide is preferably 10 to 70% by mass, more preferably 20 to 50% by mass; with respect to 100% by mass of metal pyrithione, the content is preferably 0.1 to 15% by mass, more preferably 0.5 to 8% by mass; with respect to medetomidine, the content is preferably 0.01 to 1% by mass, more preferably 0.03 to 0.5% by mass; with respect to bromopyrrolecarbonitrile, the content is preferably 0.5 to 10% by mass, more preferably 3 to 7% by mass; and with respect to DCOIT, the content is preferably 0.1 to 8% by mass, more preferably 0.5 to 5% by mass.

[0126] Pigment (D)

[0127] The underwater antifouling coating composition of the present invention may contain a pigment (D) for the purpose of coloring the coating film, concealing the base, and / or adjusting the coating film strength to be appropriate. The pigment (D) may be used alone or in combination of two or more.

[0128] It should be noted that zinc oxide is sometimes used as a pigment (extender pigment) in conventional antifouling coating compositions. The "specific surface area of ​​5 to 20 m 2 / g of zinc oxide (B)" is not considered to belong to the pigment (D) as an optional component, but it does not deny that it can exert the effect of coloring the coating film, hiding the base and / or adjusting the appropriate coating film strength in the same manner as the pigment (D) together with the effect of the present invention regarding antifouling properties. In addition, in the underwater antifouling coating composition of the present invention, as the pigment (D), "a specific surface area of ​​5 to 20 m 2 / g of zinc oxide (B)" does not meet the specific surface area of ​​5 to 20m 2 / g (for example, the specific surface area is less than 5m 2 In this case, the total amount of zinc oxide is preferably 20% by mass or more and preferably 80% by mass or less relative to 100% by mass of the solid content of the antifouling coating composition for underwater use, and is preferably 60% by mass or more and preferably 200% by mass or less relative to 100% by mass of the solid content of the hydrolyzable polymer (A).

[0129] Examples of the pigment (D) include zinc oxide (specific surface area of ​​5 to 20 m 2 / g of zinc oxide), zinc phosphate, talc, mica, clay, potassium feldspar, calcium carbonate, kaolin, alumina white, white carbon black, aluminum hydroxide, magnesium carbonate, barium carbonate, barium sulfate (e.g., precipitated barium sulfate), calcium sulfate (e.g., calcined gypsum), zinc sulfide and other extender pigments; and coloring pigments such as red iron oxide, titanium dioxide (titanium oxide), yellow iron oxide, carbon black, naphthol red, and phthalocyanine blue.

[0130] When the underwater antifouling coating composition of the present invention contains a pigment (D), its content can be appropriately adjusted depending on the purpose, the type of the component, etc., and is preferably 1 to 40% by mass based on 100% by mass of the solid content of the composition.

[0131] <Monocarboxylic acid compound (E)>

[0132] The underwater antifouling coating composition of the present invention may contain a monocarboxylic acid compound (E) and / or a metal ester thereof for the purpose of improving the renewal of the formed antifouling coating film from the surface in water, promoting the release of the antifouling agent (C) into water when the antifouling coating film contains it, thereby promoting the improvement of antifouling properties, and further imparting suitable water resistance to the antifouling coating film. The monocarboxylic acid compound (E) and / or its metal ester may be used alone or in combination of two or more.

[0133] Examples of the monocarboxylic acid compound (E) include versatile carbonic acid, palmitic acid, stearic acid, isostearic acid, rosin, cyclohexane acid, and salicylic acid. The monocarboxylic acid compound (E) may be used alone or in combination of two or more. For example, versatile carbonic acid and rosin are preferred.

[0134] The alkyl carboxylic acid (E) can form a metal ester (eg, copper ester). The metal ester can be formed before the preparation of the antifouling coating composition for underwater use, or can be formed by reaction with other coating components during the preparation of the antifouling coating composition for underwater use.

[0135] It should be noted that versatile carbonic acid is a mixture of branched alkyl carboxylic acids with 5 to 15 carbon atoms, primarily 9 to 11, and particularly 10. Rosin (rosins such as gum rosin, wood rosin, and tall oil rosin, as well as rosin derivatives such as hydrogenated rosin and disproportionated rosin) is a mixture of abietic acid and its isomers, each containing three ring structures containing conjugated double bonds and a carboxyl group. Naphthenic acid, salicylic acid, and the like are also compounds with ring structures and carboxyl groups.

[0136] When the underwater antifouling coating composition of the present invention contains a monocarboxylic acid compound (E) and / or a metal ester thereof, the content thereof can be appropriately adjusted according to the type and properties of the component, taking into account the effects of the present invention, etc. The content of the monocarboxylic acid compound (E) and / or a metal ester thereof is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and preferably 10% by mass or less, more preferably 7% by mass or less, relative to 100% by mass of the solid content of the underwater antifouling coating composition.

[0137] <Defoaming agent (F)>

[0138] The underwater antifouling coating composition of the present invention may contain a defoaming agent (surface conditioner, leveling agent) (F) for the purpose of making the formed coating film smooth, etc. The defoaming agent (F) may be used alone or in combination of two or more.

[0139] As the defoaming agent (F), commercially available defoaming agents such as silicone defoaming agents, fluorine-containing defoaming agents, and polymer defoaming agents can be used without restriction, and examples thereof include: "BYK-066N" (manufactured by BYK Chemie Japan Co., Ltd., silicone defoaming agent), "BYK-350" (manufactured by BYK Chemie Japan Co., Ltd., surface conditioner, acrylic copolymer), and "BYK-354" (manufactured by BYK Chemie Japan Co., Ltd., defoaming agent, acrylic polymer).

[0140] When the underwater antifouling coating composition of the present invention contains a defoaming agent (F), the content thereof can be appropriately adjusted depending on the purpose, the type of the component, etc., and is, for example, preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and preferably 3% by mass or less, more preferably 1% by mass or less, relative to 100% by mass of the solid content of the composition.

[0141] Solvent (G)

[0142] For the purpose of adjusting the viscosity of the composition, the antifouling coating composition for use in water of the present invention may contain a solvent (G) such as water or an organic solvent. It should be noted that the antifouling coating composition of the present invention can be prepared using a liquid containing the hydrolyzable polymer (A) obtained when synthesizing the hydrolyzable polymer (A). In this case, the solvent contained in the liquid, the solvent added when mixing the hydrolyzable polymer (A), zinc oxide (B), and optional components as required, etc., are equivalent to the solvent (G). Only one solvent (G) may be used, or two or more solvents may be used. As the solvent (G), an organic solvent is preferred.

[0143] Examples of the organic solvent include aromatic organic solvents such as xylene, toluene, and ethylbenzene; ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; aliphatic (having 1 to 10 carbon atoms, preferably about 2 to about 5 carbon atoms) monohydric alcohols such as ethanol, isopropanol, n-butanol, isobutanol, and propylene glycol monomethyl ether; and ester solvents such as ethyl acetate and butyl acetate.

[0144] When the antifouling coating composition of the present invention contains a solvent (G), its content can be appropriately adjusted depending on the purpose, the type of the component, etc., and is preferably 0 to 50% by mass based on 100% by mass of the composition.

[0145] <Anti-sagging agent / anti-settling agent (H)>

[0146] The underwater antifouling coating composition of the present invention may contain an anti-sagging agent / anti-settling agent (H) for the purpose of adjusting the viscosity of the composition, etc. The anti-sagging agent / anti-settling agent (H) may be used alone or in combination of two or more.

[0147] Examples of anti-sagging / anti-settling agents (H) include organoclay waxes (e.g., stearates, lecithin salts, and alkylsulfonates of Al, Ca, and Zn), organic waxes (e.g., polyethylene wax, oxidized polyethylene wax, fatty acid amide wax, and hydrogenated castor oil wax), mixtures of organoclay waxes and organic waxes, and synthetic finely divided silica. Examples of commercially available anti-sagging / anti-settling agents (H) include "Dispalon 305," "Dispalon 4200-20," "Dispalon A630-20X," and "Dispalon 6900-20X" manufactured by Kusumoto Chemicals Co., Ltd. and "ASA D-120" manufactured by Ito Oil Products Co., Ltd.

[0148] When the underwater antifouling coating composition of the present invention contains an anti-sagging agent / anti-settling agent (H), the content thereof can be appropriately adjusted depending on the purpose, the type of the component, etc., and is, for example, preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and preferably 10% by mass or less, more preferably 3% by mass or less, relative to 100% by mass of the solid content of the composition.

[0149] <Plasticizer (I)>

[0150] The underwater antifouling coating composition of the present invention may contain a plasticizer (I) for the purpose of imparting plasticity to the formed antifouling coating film, etc. The plasticizer (I) may be used alone or in combination of two or more.

[0151] Examples of the plasticizer (I) include chlorinated paraffin, normal paraffin, tricresyl phosphate (TCP), dioctyl phthalate (DOP), and diisodecyl phthalate (DIDP), with chlorinated paraffin and TCP being preferred.

[0152] Chlorinated paraffin may have a linear or branched molecular structure, and may be in a liquid or solid state (eg, powder) at room temperature (eg, 23° C.).

[0153] The average number of carbon atoms in one molecule of the chlorinated paraffin is preferably 8 or more, more preferably 10 or more, and preferably 30 or less, more preferably 26 or less. If the average number of carbon atoms is less than 8, the effect of suppressing the formation of cracks in the formed antifouling coating may be insufficient. On the other hand, if the average number of carbon atoms exceeds 30, the hydrolysis properties (coating film consumption, renewal properties, and abrasion resistance) of the formed antifouling coating may be too low, resulting in poor antifouling properties.

[0154] The viscosity of the chlorinated paraffin (unit: poise, measurement temperature: 25°C) is preferably 1 or more, more preferably 1.2 or more. The specific gravity (25°C) is preferably 1.05 g / cm3 More preferably, 1.10 g / cm 3 Above, and preferably 1.80 g / cm 3 Below, more preferably 1.70g / cm 3 the following.

[0155] The chlorination rate (chlorine content) of the chlorinated paraffin is usually 35 to 70% by mass, preferably 35 to 65% by mass, when the chlorinated paraffin is taken as 100% by mass.

[0156] When the underwater antifouling coating composition of the present invention contains a plasticizer (I), the content thereof is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and preferably 10% by mass or less, more preferably 5% by mass or less, relative to 100% by mass of the solid content of the underwater antifouling coating composition of the present invention, from the perspective of being able to maintain good plasticization of the antifouling coating film.

[0157] <Binder component (J)>

[0158] The underwater antifouling coating composition of the present invention may contain a binder component (J) for the purpose of imparting water resistance, crack resistance, strength, etc. to the formed antifouling coating film. It should be noted that the binder component (J) refers to the components other than the polymer (A) in the binder component. The binder component (J) may be used alone or in combination of two or more.

[0159] Examples of the binder component (J) include polyester polymers, (meth)acrylic polymers (copolymers), vinyl polymers (copolymers), terpene-phenol resins, petroleum resins, and ketone resins. Among these, polyester polymers, (meth)acrylic polymers (copolymers), vinyl polymers (copolymers), and petroleum resins are preferred, and polyester polymers and petroleum resins are more preferred.

[0160] When the underwater antifouling coating composition of the present invention contains a binder component (J), its content can be appropriately adjusted depending on the purpose, the type of the component, etc., and is preferably 0.1 to 40% by mass based on 100% by mass of the solid content of the composition.

[0161] <Method for preparing underwater antifouling coating composition>

[0162] The underwater antifouling coating composition of the present invention can be prepared using components (A) and (B), and optionally components (C) to (J), and other optional components by the same means (apparatus, method, conditions, etc.) as conventional antifouling coating compositions. Specifically, it can be prepared by synthesizing the hydrolyzable polymer (A), then adding the resulting (solution of) the hydrolyzable polymer (A), zinc oxide (B), and optionally components (C) to (J), and other optional components to a container all at once or sequentially, and stirring and mixing.

[0163] -Antifouling coating-

[0164] The antifouling coating film of the present invention is formed from the underwater antifouling coating composition of the present invention. Similar to the case of forming existing antifouling coating films from existing antifouling coating compositions, the antifouling coating film of the present invention is formed by drying the underwater antifouling coating composition of the present invention. However, the antifouling coating film of the present invention is not limited to the antifouling coating film immediately formed from the underwater antifouling coating composition of the present invention; antifouling coating films that have deteriorated due to use are also included in the antifouling coating film of the present invention. Regarding the antifouling coating film of the present invention, the immediately formed antifouling coating film contains the same substances as the antifouling coating composition of the present invention, except for volatile components such as solvents that have been lost due to drying, etc., and the used antifouling coating film contains the same substances as the antifouling coating composition of the present invention, except for volatile components and some components that have been lost (released) due to the volatilization of antifouling properties.

[0165] The thickness of the antifouling coating of the present invention is not particularly limited and can be set within an appropriate range depending on the properties of the antifouling coating of the present invention (e.g., coating consumption rate) and the intended use (type of substrate, duration of use, etc.). For example, the thickness in the immediately formed state is preferably 30 to 1000 μm.

[0166] The antifouling coating film of the present invention is preferably an antifouling coating film having a light / dark rubbed film thickness ratio of 1.5 or more as measured by the following method.

[0167] (Light and dark grinding film thickness ratio)

[0168] A test plate formed with an antifouling coating is fixed to the surface of a rotating drum. The drum is rotated at a speed of 10 knots in a water tank filled with seawater, which is replaced at a constant rate, in a room. The test plate is placed in a location exposed to sunlight (bright area) and a location shielded from sunlight (dark area) for 3 months. The ratio of the coating film consumption in the bright area to the coating film consumption in the dark area (film thickness at the beginning - film thickness after 3 months) is measured.

[0169] It should be noted that the water exchange rate, seawater temperature, and sunlight transmittance in the bright area used in the above-mentioned measurement method can be appropriately adjusted based on the environment in which the antifouling coating is used. As an example, it is possible to consider the case where the antifouling coating of the present invention is used as a substrate for a ship, with the vertical portion of the ship's bottom as the bright area and the flat bottom portion of the ship as the dark area. These conditions can be adjusted while taking into account the environment of the sea area in which the ship may operate.

[0170] In another aspect, the present invention provides an antifouling coating film comprising a hydrolyzable polymer containing a metal ester group and zinc oxide, wherein the light / dark rubbed film thickness ratio measured by the above-mentioned method is 1.5 or more. The antifouling coating film in another aspect of the present invention is composed of the above-mentioned underwater antifouling coating composition of the present invention, i.e., comprising a hydrolyzable polymer containing a metal ester group and zinc oxide having a specific surface area of ​​5 to 20 m 2 The invention also relates to an antifouling coating film formed from an antifouling coating composition for use in water containing a zinc oxide (B) of 0.1% to 0.1% by weight, including an antifouling coating film having a light-to-dark washed film thickness ratio of 1.5 or more. In addition, the invention also includes an antifouling coating film formed from an antifouling coating composition for use in water containing a hydrolyzable polymer (A) containing a metal ester group and zinc oxide having a specific surface area that does not satisfy the above conditions, or an antifouling coating film formed from an antifouling coating composition for use in water containing a hydrolyzable polymer (A) containing a metal ester group and zinc oxide having an unknown specific surface area, and an antifouling coating film having a light-to-dark washed film thickness ratio of 1.5 or more.

[0171] -Substrate with antifouling coating-

[0172] The substrate with an antifouling coating film of the present invention comprises a substrate and the antifouling coating film of the present invention. The antifouling coating film of the present invention is usually formed on a substrate and used as the substrate with an antifouling coating film.

[0173] The substrate is not particularly limited as long as it is a substrate on which the antifouling coating of the present invention can be formed and on which its function can be exerted. Examples thereof include ships (e.g., hull plates of large steel ships such as container ships, oil tankers, and bulk carriers, fishing boats, FRP ships, wooden boats, yachts, etc., including new ships and ships under repair), fishing or other marine materials (e.g., ropes, fishing nets, fishing gear, floats, buoys, diving suits, diving goggles, oxygen cylinders, swimsuits, torpedoes), underwater structures (e.g., oil pipelines, water pipes, circulating water pipes, water supply and drainage outlets of thermal power plants and nuclear power plants, submarine cables, seawater utilization equipment (seawater pumps, etc.), giant floating structures, coastal roads, submarine tunnels, port facilities, various underwater civil engineering structures such as canals and waterways), and the like, which are wholly or at least partially submerged in water, preferably in seawater. In view of the effects of the present invention, ships (new ships or ships after operation) are preferred as substrates, and large steel ships such as container ships, oil tankers, and bulk carriers having submerged parts that are exposed to sunlight for a long time and easily fouled by algae are particularly preferred.

[0174] The substrate may be a substrate treated with a rust preventive agent or other treatment agent, a substrate having a coating other than an antifouling coating such as a rust preventive coating (e.g., zinc-rich paint), an anticorrosion coating (e.g., epoxy-based heavy anticorrosion coating), or an adhesive coating formed on the surface (non-antifouling coating), or a substrate having an antifouling coating of the present invention that has deteriorated, deteriorated, or consumed, or an antifouling coating formed from another antifouling coating composition (old antifouling coating). In the substrate with an antifouling coating of the present invention, the antifouling coating does not necessarily need to be formed in direct contact with the surface of the substrate, and may be formed on the substrate via a treatment agent, other coating, or the like. Therefore, the substrate with an antifouling coating of the present invention may contain other treatment agents, coatings, or the like in addition to the substrate and the antifouling coating of the present invention. The antifouling coating of the present invention may be formed on various non-antifouling coatings, deteriorated antifouling coatings, or the like.

[0175] The "non-antifouling coating film" possessed by the substrate refers to a coating film other than the antifouling coating film, such as a primer coating film and a mid-coat coating film, which are formed on the substrate in advance before forming the antifouling coating film of the present invention, depending on the type and purpose of the substrate. The type of non-antifouling coating film is not particularly limited, and examples thereof include: an antirust coating film formed by an antirust paint, an anticorrosion coating film formed by an anticorrosion paint, an adhesive coating film formed by an adhesive coating, etc. As an anticorrosion coating film, for example, an anticorrosion coating film formed by an anticorrosion paint containing an epoxy resin can be cited. As an adhesive coating film, for example, an adhesive coating film formed by an adhesive coating containing one or more resins selected from epoxy, vinyl, (meth) acrylic, etc. can be cited. It should be noted that when applied to a substrate such as a ship, there is no clear distinction between the anticorrosion coating film (primer coating film) and the adhesive coating film (mid-coat coating film), and a coating film that combines both is sometimes used, but a "non-antifouling coating film" may also be an adhesive coating film that simultaneously has the function of such an anticorrosion coating film.

[0176] The portion of the substrate on which the antifouling coating of the present invention is formed is not particularly limited and can be appropriately selected depending on the intended use. For example, in the case of a ship, the permanently submerged portion or the alternating wet-dry portion exposed to a biofouling environment can be designated as the portion (a portion of the substrate) on which the antifouling coating of the present invention is formed. It should be noted that in the case of a ship, the antifouling coating of the present invention is not limited to the bottom of the ship (permanently submerged portion) but also includes the waterline (alternating wet-dry portion). Furthermore, regardless of whether the portion is exposed to sunlight, the antifouling coating of the present invention can be formed over the entire portion of the portion on which a conventional antifouling coating is formed.

[0177] The "old antifouling coating film" possessed by the substrate refers to an antifouling coating film that has been used after being in contact with water (seawater) for a certain period of time (for example, the durability period of the antifouling coating film), and is an antifouling coating film that is in a state of deterioration, deterioration or consumption compared to the healthy antifouling coating film before use (before immersion in seawater). The degree of deterioration, deterioration or consumption of the antifouling coating film is not particularly limited, as long as it is considered necessary or preferable to form the antifouling coating film of the present invention. The type of antifouling coating film is not particularly limited, and it can be the antifouling coating film of the present invention or other antifouling coating films. Examples of the antifouling coating film include hydrolysis type (for example, a coating film formed from a silyl ester resin antifouling coating film) and hydration decomposition type (for example, a coating film formed from a vinyl chloride-isobutyl vinyl ether resin antifouling coating film).

[0178] -Method for manufacturing a substrate with an antifouling coating-

[0179] The method for producing a substrate with an antifouling coating of the present invention comprises the following steps (1) and (2):

[0180] (1) a step of applying the antifouling coating composition for underwater use of the present invention to a substrate or impregnating the substrate to obtain a coated body or an impregnated body;

[0181] (2) A step of drying the coated or impregnated body.

[0182] The coating in step (1) can be carried out by a conventional method, for example, a method of applying the antifouling coating composition to the substrate using an airless sprayer, an air sprayer, a brush, a roller, etc. The impregnation in step (1) can also be carried out by a conventional method, for example, a method of immersing the substrate in the antifouling coating composition.

[0183] The coating or impregnation conditions may also be adjusted in consideration of the drying conditions in step (2) so that an antifouling coating film having a target thickness can be formed. For example, an appropriate amount of the antifouling coating composition per unit area of ​​the substrate may be applied or impregnated so that the thickness of the dried coating film after step (2) is 10 to 300 μm, preferably 30 to 200 μm.

[0184] Furthermore, in the case where the substrate on which the antifouling coating film is to be formed is predicted in advance as to whether the site is a site where algae or the like easily grow (bright site) or a site where algae or the like do not easily grow (dark site), the amount of the antifouling coating composition applied or impregnated in step (1), that is, the thickness of the dried coating film after step (2), can be adjusted according to the site. For example, when the substrate is the bottom of a ship and it is desired to form an antifouling coating film by applying the underwater antifouling coating composition of the present invention having the same composition thereon, in step (1), the underwater antifouling coating composition is applied more to the site of the ship bottom that is easily exposed to sunlight due to the water depth, shape, etc., and is applied less to the site of the ship bottom that is not easily exposed to sunlight due to the water depth, shape, etc. (particularly, a flat bottom). This allows, after step (2), to form thick and thin antifouling coating films, that is, to impart a gradient to the dry film thickness of the antifouling coating film. In addition, as another definition of the part that is easily exposed to sunlight and the part that is not easily exposed to sunlight, based on the position of the full load waterline of the vertical part of the bottom of the ship and the position equivalent to the flat bottom, the upper half from the middle between the two positions is set as the part that is easily exposed to sunlight, and the lower half is set as the part that is not easily exposed to sunlight, or the range from the full load waterline to a specific water depth, for example, a position equivalent to 3 meters or 5 meters below the full load waterline, is set as the part that is easily exposed to sunlight, and then the position with a water depth deeper than that position is set as the part that is not easily exposed to sunlight, etc.

[0185] The drying in step (2) can be carried out according to conventional methods at an appropriate temperature and under other conditions for an appropriate time. For example, a method can be used in which the coated or impregnated body obtained in step (1) is left at room temperature (e.g., 25°C) for preferably 0.5 to 14 days, more preferably 1 to 7 days. Drying in this step can be carried out under heating or with ventilation.

[0186] Steps (1) and (2) may be repeated as needed. For example, if an antifouling coating film having a desired thickness cannot be formed by performing steps (1) and (2) only once, steps (1) and (2) may be performed a second time after the first step (1) and (2), and steps (1) and (2) may be performed a further number of times as necessary.

[0187] In one embodiment of the present invention, the method for producing a substrate with an antifouling coating film of the present invention comprises, as step (1), a step of applying the antifouling coating composition of the present invention onto a substrate having an old antifouling coating film or impregnating the substrate having an old antifouling coating film to obtain a coated body or an impregnated body. In this embodiment, a necessary step, such as a step of removing dirt on the surface of the old antifouling coating film by washing with water or the like and drying the old antifouling coating film, may be further included before step (1).

[0188] -Other aspects of the present invention-

[0189] The underwater antifouling coating composition, antifouling coating film, substrate with an antifouling coating film, and method for producing a substrate with an antifouling coating film described in this specification can be converted into other inventions based on patent practice and technical common sense.

[0190] For example, the "method for producing a substrate with an antifouling coating film" of the present invention can be converted into a "substrate antifouling method" comprising the step of forming the antifouling coating film of the present invention on at least a portion of the substrate. The "step of forming the antifouling coating film" in the "substrate antifouling method" is basically the same as the above-mentioned steps (1) and (2) in the "substrate antifouling method for producing a substrate with an antifouling coating film." In other words, the substrate antifouling method of the present invention comprises: (1') the step of applying the underwater antifouling coating composition of the present invention to at least a portion of the substrate or impregnating at least a portion of the substrate to obtain a coated body or an impregnated body; and (2') the step of drying the coated body or the impregnated body. In addition, in this specification, the technical matters described in the "method for producing a substrate with an antifouling coating film" can be appropriately replaced with the technical matters related to the "substrate antifouling method." For example, in an embodiment in which the substrate is a substrate having a deteriorated antifouling coating film, the "substrate antifouling method" of the present invention can be replaced with the "method for repairing a substrate with a deteriorated antifouling coating film."

[0191] Example

[0192] (1) Production Example of Synthesis of Metal Ester Group-Containing Monomer

[0193] [Manufacturing Example M1] Manufacture of Metal Ester Group-Containing Monomer Mixture Solution (M-1)

[0194] 85.4 parts of propylene glycol monomethyl ether (PGM) and 40.7 parts of zinc oxide were added to a four-necked flask equipped with a cooler, a thermometer, a dropping funnel and a stirrer, and the temperature was raised to 75°C while stirring. Then, a mixture of 43.1 parts of methacrylic acid, 36.1 parts of acrylic acid and 5 parts of water was added dropwise from the dropping funnel at a constant rate over 3 hours. After further stirring for 2 hours, 36 parts of PGM were added to obtain a transparent metal ester group-containing monomer mixture solution (M-1). The solid content in the solution (M-1) was 44.8% by mass. It should be noted that the solution (M-1) contains zinc diacrylate, zinc dimethacrylate and zinc methacrylate as a mixture of metal ester group-containing monomers (a1) belonging to compound (1').

[0195] (2) Production Example of Synthesis of Metal Ester Group-Containing Hydrolyzable Copolymer

[0196] [Manufacturing Example A1] Manufacture of a hydrolyzable copolymer solution (A-1)

[0197] In a four-necked flask equipped with a cooler, thermometer, dropping funnel, and stirrer, 15 parts of PGM, 61 parts of xylene, and 4 parts of ethyl acrylate (EA) were placed and heated to 100±5°C while stirring. While maintaining this temperature, 37.8 parts of the metal ester group-containing monomer mixture solution (M-1), 18 parts of methyl methacrylate (MMA), 61 parts of ethyl acrylate (EA), 2.5 parts of 2,2'-azobisisobutyronitrile (AIBN) as a polymerization initiator, 7 parts of 2,2'-azobis(2-methylbutyronitrile) (AMBN) as a polymerization initiator, 1 part of "Nofmer MSD" (product name, manufactured by NOF Corporation, α-methylstyrene dimer) as a chain transfer agent, and 10 parts of xylene were added dropwise from the dropping funnel at a constant rate over 6 hours. After completion of the dropwise addition, 0.5 parts of tert-butyl peroctoate (TBPO) and 7.0 parts of xylene as a polymerization initiator were added dropwise over 30 minutes, and the mixture was further stirred for 1 hour and 30 minutes. Then, 8.2 parts of xylene was added to obtain a light yellow transparent hydrolyzable copolymer solution (A-1).

[0198] [Manufacturing Example A2] Manufacture of a hydrolyzable copolymer solution (A-2)

[0199] Into a four-necked flask equipped with a cooler, a thermometer, a dropping funnel, and a stirrer were placed 15 parts of n-butanol, 56 parts of xylene, and 4 parts of ethyl acrylate (EA), and the temperature was raised to 100±5°C while stirring. While maintaining this temperature, 31.3 parts of the metal ester group-containing monomer mixture solution (M-1), 12.5 parts of n-butyl acrylate (n-BA), 30.2 parts of MMA, 23.2 parts of EA, 6 parts of 2-methoxyethyl acrylate (2-MEA), 10 parts of "X-22-174ASX" (product name, single-end methacryloyloxyalkyl-modified organopolysiloxane, manufactured by Shin-Etsu Chemical Co., Ltd.), 0.8 part of "Nofmer MSD", 1 part of AIBN, 8 parts of AMBN, and 10 parts of xylene were added dropwise from the dropping funnel at a constant rate over 6 hours. After completion of the dropwise addition, 2 parts of TBPO and 7 parts of xylene were added dropwise over 90 minutes, and the mixture was further stirred for 60 minutes. Thereafter, 7.5 parts of xylene was added to obtain a colorless and transparent hydrolyzable copolymer solution (A-2).

[0200] [Manufacturing Example A3] Manufacture of a hydrolyzable copolymer solution (A-3)

[0201] Into a pressure polymerization-capable autoclave equipped with a cooler, thermometer, dripping tank, and stirrer, 15 parts of PGM, 60 parts of xylene, and 4 parts of EA were placed. The mixture was then pressurized to 350 kPa while stirring and heated to 135°C. Subsequently, 15 parts of MMA, 48 parts of EA, 15 parts of n-BA, 40 parts of the metal ester group-containing monomer mixture solution (M-1), 10 parts of xylene, 1.2 parts of "Nofmer MSD," 3 parts of AIBN, and 1 part of AMBN were added dropwise from the dripping tank at a constant rate over 3 hours. After the addition was complete, the temperature was lowered to 110°C over 30 minutes, and 0.5 parts of TBPO and 5 parts of xylene were added dropwise over 30 minutes. The mixture was further stirred for 1 hour and 30 minutes, and then 8 parts of xylene was added. The resulting mixture was filtered through 300 mesh to obtain a hydrolyzable copolymer solution (A-3) as a light yellow, transparent filtrate free of insoluble matter. As the 300-mesh filtration residue, a small amount of insoluble matter was observed.

[0202] <Solid content of copolymer solution (residue after heating)>

[0203] The solid content of the hydrolyzable copolymer solutions (A-1) to (A-3) was determined by measuring the mass of each solution dried in a hot air dryer at 108°C for 3 hours in accordance with JIS K 5601-1-2:2008 and calculating the ratio to the mass of the original solution.

[0204] <Viscosity of copolymer solution>

[0205] The Gardner viscosity of the hydrolyzable copolymer solutions (A-1) to (A-3) was measured at 25°C using a Gardner bubble viscometer.

[0206] <Weight average molecular weight (Mw) of copolymer>

[0207] The weight average molecular weight (Mw) of the copolymer contained in the hydrolyzable copolymer solutions (A-1) to (A-3) was measured by gel permeation chromatography (GPC) under the following conditions.

[0208] Device: "HLC-8320GPC" (manufactured by Tosoh Corporation)

[0209] Column: "TSKgelG4000HXL G2000HXL" (Made by Tosoh Corporation, size 7.8mm ID × 30cm L)

[0210] Eluent: THF (1 mmol citric acid)

[0211] Flow rate: 1.000ml / min

[0212] Detector: RI

[0213] Column thermostat temperature: 40°C

[0214] Standard material: polystyrene

[0215] Sample preparation method: 1 mmol of THF (tetrahydrofuran) containing citric acid was added to the copolymer solution prepared in each production example to dilute the solution to a solid content concentration of 0.4 wt %. The solution was then filtered through a membrane filter and the resulting filtrate was used as a GPC measurement sample.

[0216] Table 1 shows information (monomers and properties) on the hydrolyzable copolymer solutions (A-1) to (A-3).

[0217]

[0218] (3) Preparation of antifouling coating compositions of Examples 1 to 7 and Comparative Examples 1 to 2

[0219] 7 parts of xylene as a solvent, 3 parts of propylene glycol monomethyl ether (product name), 0.5 parts of versatile carbonic acid, and 45 parts of the hydrolyzable polymer solution (A-1) were added to a plastic container and mixed using a paint shaker until the components were uniformly dispersed or dissolved. Subsequently, 25 parts of zinc oxide 0.12 μm, 2 parts of red iron oxide, 0.5 parts of calcium sulfate, 11 parts of barium sulfate, 4 parts of talc, and 0.5 parts of oxidized polyethylene wax were added to the plastic container and stirred using a paint shaker for 1 hour to disperse the components. After dispersion, 1.5 parts of fatty acid amide wax was added and stirred using a paint shaker for 20 minutes. The mixture was then filtered through a filter (80 mesh) to remove the residue, yielding the antifouling coating composition of Example 1 as the filtrate.

[0220] The antifouling coating compositions of Examples 2 to 7 and Comparative Examples 1 and 2 were obtained by the same preparation method as above, except that the amounts of the components were changed as shown in Table 2. In Examples 3 to 5, the raw materials corresponding to the antifouling agent (C) were added at the same stage as zinc oxide (B) and the like.

[0221] It should be noted that the amount of each component described in Table 2 represents the amount of the compounding by wet weight. For example, the amount of the fatty acid amide wax in Example 1 (as a whole) is 1.5 parts by wet weight, and the solid content is 20% by mass, so the amount of the fatty acid amide wax is 0.3 parts.

[0222] (4) Evaluation test

[0223] (4-1) Light and dark grinding film thickness ratio (ratio of coating film consumption in light area / dark area)

[0224] Each antifouling coating composition prepared in the Examples and Comparative Examples was applied to a 50×50×1.5 mm hard vinyl chloride plate using an applicator to a dry film thickness of approximately 150 μm. The plate was then dried indoors at room temperature (approximately 20° C.) for 7 days to prepare a test plate (test plate 1) with an antifouling coating film for a consumption test.

[0225] After measuring the coating film thickness, the test plate 1 was fixed to the sides of two rotating drums. The drum was rotated at a speed of 10 knots in an outdoor water tank filled with seawater, with the water constantly changing. One side of the tank was transparent, allowing sunlight to pass through (light area), while the other side was shielded from sunlight (dark area). The film thickness was measured after three months, and the ratio of the coating film consumption in the light area to the coating film consumption in the dark area was calculated (film thickness at the start of the test minus film thickness after three months).

[0226] (4-2) Static antifouling performance

[0227] An epoxy anticorrosion coating ("BANNOH 500" manufactured by China Paint Co., Ltd.) was applied to a sandblasted steel plate (300 mm long x 100 mm wide x 2.3 mm thick) to a dry film thickness of 150 μm and then dried at room temperature for one day to form a coating film. An epoxy binder coating ("BANNOH 500N" manufactured by China Paint Co., Ltd.) was applied to the surface of this anticorrosion coating film to a dry film thickness of 100 μm and then dried at room temperature for one day. Furthermore, each antifouling coating composition prepared in the Examples and Comparative Examples was applied to this coating film to a dry film thickness of 100 μm and dried at room temperature for 7 days to prepare a test plate (Test Plate 2) with an antifouling coating film for use in a static antifouling property test.

[0228] The test panels 2 were placed 0.3 meters below the sea surface in Hiroshima Bay during winter, with the test panel facing the sea surface and aligned with the sea surface. Three months later, the aquatic organism adhesion area on the antifouling coating of each test panel was measured, and the static antifouling performance of the antifouling coating was evaluated according to the following antifouling performance evaluation criteria.

[0229] <Evaluation criteria for antifouling performance / 0, 1, and 2 points are considered passing scores>

[0230] 0: No marine organisms attached

[0231] 1: The attachment area of ​​marine organisms is less than 1% of the total

[0232] 2: The attachment area of ​​marine organisms is more than 1% and less than 10% of the total area

[0233] 3: The attachment area of ​​marine organisms is more than 10% and less than 30% of the total area

[0234] 4: The attachment area of ​​marine organisms is more than 30% and less than 70% of the total area

[0235] 5: The attachment area of ​​marine organisms is more than 70% of the total

[0236] (4-3) Dynamic antifouling performance

[0237] A sandblasted steel plate (170 mm long x 70 mm wide x 2.3 mm thick) was prepared and bent so that it could be attached to the side of a rotating drum on a test raft anchored in Kure Bay, Hiroshima Prefecture. An epoxy anticorrosion coating ("BANNOH 500," manufactured by China Paint Co., Ltd.) was applied to the sandblasted steel plate to a dry film thickness of 150 μm and then dried at room temperature for one day to form a coating film. An epoxy adhesive coating ("BANNOH 500N," manufactured by China Paint Co., Ltd.) was applied to the surface of this anticorrosion coating film to a dry film thickness of 100 μm and then dried at room temperature for one day. Furthermore, each antifouling coating composition prepared in the Examples and Comparative Examples was applied to this coating film to a dry film thickness of 100 μm and dried at room temperature for seven days to prepare a test plate (Test Plate 3) with an antifouling coating film for dynamic antifouling testing.

[0238] The test panels 3 were mounted on a rotating drum located 1 meter below the sea surface in Hiroshima Bay during winter and rotated at a speed equivalent to 15 knots. Six months later, the aquatic organism attachment area on the antifouling coating of each test panel was measured, and the dynamic antifouling properties of the antifouling coating were evaluated according to the following antifouling performance evaluation criteria.

[0239] <Evaluation criteria for antifouling performance / 0, 1, and 2 points are considered passing scores>

[0240] 0: No marine organisms attached

[0241] 1: The attachment area of ​​marine organisms is less than 1% of the total

[0242] 2: The attachment area of ​​marine organisms is more than 1% and less than 10% of the total area

[0243] 3: The attachment area of ​​marine organisms is more than 10% and less than 30% of the total area

[0244] 4: The attachment area of ​​marine organisms is more than 30% and less than 70% of the total area

[0245] 5: The attachment area of ​​marine organisms is more than 70% of the total

[0246] Information (composition and evaluation test results) on the antifouling coating compositions of Examples 1 to 7 and Comparative Examples 1 and 2 is shown in Table 2. Table 3 also shows details of the components (products) listed in Table 2 used in the preparation of these antifouling coating compositions.

[0247]

[0248]

[0249] By comparing the results of the evaluation tests of the Examples and Comparative Examples described in Table 2, the following results can be obtained, for example. (1) Compared with the antifouling coating composition containing no zinc oxide (Comparative Example 2), the antifouling coating composition (Comparative Example 1) to which zinc oxide whose specific surface area does not meet the specified conditions is added has a small increase in the light and dark rubbed film thickness ratio, and neither the static antifouling property nor the dynamic antifouling property is sufficiently improved. In contrast, the antifouling coating compositions (Examples 1 and 2) to which zinc oxide whose specific surface area meets the specified conditions is added have a significantly increased light and dark rubbed film thickness ratio, and both the static antifouling property and the dynamic antifouling property are significantly improved. When the hydrolyzable copolymer is changed (Example 3), the content of the extender pigment (barium sulfate) is increased (Example 4), and the antifouling agent (C) is added (Examples 5 to 7), the light and dark rubbed film thickness ratio is large, and both the static antifouling property and the dynamic antifouling property are excellent.

Claims

1. An antifouling coating composition for use in water, comprising a hydrolyzable polymer (A) containing a metal ester group and a polymer having a specific surface area of ​​5 to 20 m 2 / g of zinc oxide (B).

2. The underwater antifouling coating composition according to claim 1, wherein The content of the zinc oxide (B) is 50 to 150% by mass relative to 100% by mass of the solid content of the hydrolyzable polymer (A).

3. The underwater antifouling coating composition according to claim 1 or 2, wherein: Also contains an antifouling agent (C).

4. The underwater antifouling coating composition according to claim 1 or 2, wherein: It further contains a monocarboxylic acid compound (E) and / or a metal ester thereof.

5. An antifouling coating film formed from the underwater antifouling coating composition according to claim 1 or 2. A substrate with an antifouling coating film, comprising a substrate and the antifouling coating film according to claim 5.

7. A method for producing a substrate with an antifouling coating, comprising: Step (1) of applying the underwater antifouling coating composition according to claim 1 or 2 onto a substrate or impregnating the substrate to obtain a coated body or an impregnated body; and A step (2) of drying the coated or impregnated body.

8. The method for producing a substrate with an antifouling coating according to claim 7, wherein: The substrate is the bottom of a ship. In the step (1), the underwater antifouling coating composition having the same composition is applied more to a portion that is easily exposed to sunlight and less to a portion that is less exposed to sunlight, thereby giving a gradient to the film thickness of the antifouling coating film formed after the step (2).

9. An antifouling coating film comprising a hydrolyzable polymer containing a metal ester group and zinc oxide, wherein: The light and dark wash film thickness ratio measured by the following method is 1.5 or more, (Light and dark grinding film thickness ratio) A test plate formed with an antifouling coating is fixed to the surface of a rotating drum. The drum is rotated at a speed of 10 knots in a water tank filled with seawater, which is replaced at a constant rate, in a room. The test plate is placed in a location exposed to sunlight (bright area) and a location shielded from sunlight (dark area) for 3 months. The ratio of the coating film consumption in the bright area to the coating film consumption in the dark area (film thickness at the beginning - film thickness after 3 months) is measured. 10 . A substrate with an antifouling coating film, comprising a substrate and the antifouling coating film according to claim 9 .

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