Agent for promoting attachment of aquatic organisms

Abstract

To provide an agent that exhibits an effect in promoting attachment of aquatic organisms, which enables a waterside environment to be adapted for attachment of desired algae and aquatic animals.SOLUTION: An agent for promoting attachment of aquatic organisms contains rare earth ferrite and is employed for selective attachment of aquatic organisms selected from aquatic invertebrates and algae.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an aquatic biofouling promoter. [Background technology]

[0002] Seaweed beds have functions such as contributing to the purification of seawater and preserving coastlines. They also provide habitats for a wide variety of aquatic animals, and play a major role in maintaining the coastal and nearby sea environments.

[0003] However, in recent years, seaweed beds have been rapidly declining due to coastal development and "isoyake" (barren seaweed erosion). Causes of the decline in seaweed beds due to development include land reclamation, decreased seawater transparency, and the inflow of chemical substances into the sea. "Isoyake" refers to a decline in algae productivity caused by factors such as changes in water temperature due to changes in ocean currents and a decrease in nutrient concentration due to a decrease in upwelling currents.

[0004] Various efforts have been made to restore diminished seaweed beds and the aquatic animals that feed on them. For example, Patent Document 1 proposes an artificial seaweed bed cultivation device consisting of an anchor pile, an arm attached to the top of the anchor pile, and artificial seaweed attached to the arm. Patent Document 2 proposes a longline-type artificial floating algae system, which consists of a longline laid in the sea or on the seabed and fixed with artificial floating algae made from cut biodegradable plastic.

[0005] On the other hand, it is necessary to prevent the growth of algae in fields such as ships, revetments, and fishing nets. For this purpose, Patent Document 3 reports that rare earth ferrites having a specific composition have an anti-algae effect. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-135828 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-237357 [Patent Document 3] International Publication No. 2021 / 193644 Summary of the Invention [Problem to be solved by the invention]

[0007] The technologies in Patent Documents 1 and 2 artificially create an environment in which seaweed beds can grow, and then leave the regeneration of the seaweed beds to the natural healing power of the sea. In this case, the regenerated seaweed beds do not necessarily meet the objectives of the area.

[0008] An object of the present invention is to provide an agent that exhibits the effect of promoting the attachment of aquatic organisms, and that can make aquatic environments, including seaweed beds, suitable for the attachment of desired algae and aquatic animals. [Means for solving the problem]

[0009] The present invention is as follows.

[0010] <Embodiment 1> Contains rare earth ferrite, Used for the selective attachment of aquatic organisms selected from aquatic invertebrates and algae, Aquatic biofouling promoter. <Aspect 2> The rare earth ferrite is represented by the following formula (1): Ln 2x Fe 2(1-x) O3(1) (In formula (1), Ln is a rare earth element selected from the group consisting of lanthanum, praseodymium, neodymium, and yttrium, and x is a number equal to or greater than 0.50 and less than 1.00.) The aquatic organism adhesion promoting agent according to embodiment 1, having a composition represented by the formula: <<Aspect 3>> The aquatic organism adhesion promoter according to Aspect 2, wherein x in formula (1) is a number of 0.65 or more and 0.85 or less. Aspect 4: The aquatic organism attachment promoter according to Aspect 1, wherein the rare earth ferrite is lanthanum ferrite. <<Aspect 5>> An aquatic organism adhesion promoter according to Aspect 2, wherein Ln in formula (1) is lanthanum. Aspect 6: The aquatic organism adhesion promoter according to any one of Aspects 1 to 5, wherein the aquatic invertebrate is one or more species selected from sponges, flatworms, annelids, tentacleds, mollusks, arthropods, protochordata, and cnidarians. <<Aspect 7>> The aquatic organism attachment promoter according to any one of Aspects 1 to 5, wherein the algae is green algae. <<Aspect 8>> An algae adhesion promoting composition comprising the aquatic organism adhesion promoting agent according to any one of Aspects 1 to 5 and an aquatic invertebrate repellent. Aspect 9: The algae adhesion-promoting composition of Aspect 8, wherein the aquatic invertebrate repellent is one or more selected from organotin compounds, cuprous oxide, zinc pyrithione, copper pyrithione, organic nitrogen compounds, boron compounds, fluorine atom-containing polymers, and silicone resins. Aspect 10: The algae adhesion promoting composition according to Aspect 8, wherein the algae is green algae. Aspect 11: The algae adhesion promoting composition according to Aspect 9, wherein the algae is green algae. Aspect 12: An aquatic organism adhesion-promoting paint comprising the aquatic organism adhesion-promoting agent according to any one of Aspects 1 to 5. <<Aspect 13>> An aquatic organism adhesion-promoting article comprising the aquatic organism adhesion-promoting agent according to any one of Aspects 1 to 5. <<Aspect 14>> An algae adhesion-promoting paint comprising the aquatic organism adhesion-promoting agent according to any one of Aspects 1 to 5 and an aquatic invertebrate repellent. <<Aspect 15>> An algae adhesion promoting article comprising the aquatic organism adhesion promoting agent according to any one of Aspects 1 to 5 and an aquatic invertebrate repellent. [Effects of the Invention]

[0011] According to the present invention, there is provided an aquatic organism attachment promoter that exhibits an effect of promoting the attachment of aquatic organisms, and that can make a seaweed bed an environment suitable for the attachment of desired algae and aquatic animals. DETAILED DESCRIPTION OF THE INVENTION

[0012] <Aquatic organism adhesion promoter> The aquatic bioattachment promoter of the present invention comprises a rare earth ferrite and is used for the selective attachment of aquatic organisms selected from aquatic invertebrates and algae.

[0013] When an aquatic organism attachment-promoting article (described below) containing the aquatic organism attachment promoter of the present invention is placed in a situation where it may come into contact with water such as rivers, lakes, marshes, the sea, etc., the attachment of aquatic invertebrates and algae is promoted. Because aquatic invertebrates can feed on algae, depending on the level of feeding behavior of the aquatic invertebrates, either only aquatic invertebrates will attach to the aquatic organism attachment-promoting article, or both aquatic invertebrates and algae will be observed to attach to the article.

[0014] <Rare earth ferrite> The aquatic bioattachment promoter of the present invention comprises a rare earth ferrite.

[0015] The rare earth ferrite contained in the aquatic organism attachment promoter of the present invention is represented by the following formula (1): Ln 2x Fe 2(1-x) O3(1) (In formula (1), Ln is a rare earth element selected from the group consisting of lanthanum, praseodymium, neodymium, and yttrium, and x is a number equal to or greater than 0.50 and less than 1.00.) The composition may be represented by the formula:

[0016] The above-mentioned Patent Document 3 explains that the rare earth ferrite having the composition represented by the above formula (1) functions as an anti-algae agent that exhibits excellent anti-algae effects. However, the present inventors have found that this rare earth ferrite has the function of promoting the attachment of aquatic organisms when placed in a situation where it may come into contact with water such as rivers, lakes, and oceans.

[0017] The rare earth element (Ln) in formula (1) may particularly be lanthanum from the viewpoints of the adhesion effect of aquatic organisms, cost, etc. Therefore, the aquatic organism attachment promoter of the present invention may contain lanthanum ferrite.

[0018] The rare earth ferrite contained in the aquatic organism attachment promoter of the present invention may be in any form as long as it contains a phase in which x in formula (1) is a number of 0.50 or more and less than 1.00. For example, it may form a solid solution of uniform composition as a whole, or may be a mixture of LnFeO3 and Ln(OH)3, or may be a mixture of a solid solution of uniform composition and LnFeO3 and Ln(OH)3, or may contain phases other than these.

[0019] The rare earth ferrite contained in the aquatic organism attachment promoter of the present invention may include LnFeO3 and Ln(OH)3, and may also include lanthanum hydroxycarbonates together with LnFeO3 and Ln(OH)3. Here, "lanthanum hydroxycarbonates" is a concept that encompasses LaCO3OH and its derivatives. Derivatives of LaCO3OH include La2O2(CO3), La2O(CO3)2, etc.

[0020] The phases contained in the rare earth ferrite can be determined by XRD measurement.

[0021] In formula (1), x is 0.50 or greater, and may be 0.55 or greater, 0.60 or greater, 0.65 or greater, 0.70 or greater, or 0.75 or greater. Also, x may be less than 1.00 and 0.90 or less, 0.85 or less, 0.80 or less, 0.75 or less, 0.70 or less, 0.65 or less, or 0.60 or less.

[0022] In the above formula (1), x may typically be a number of 0.65 or more and 0.85 or less, and may further be a number of 0.70 or more and 0.80 or less.

[0023] The aquatic organism attachment promoter of the present invention preferably has a larger specific surface area from the viewpoint of increasing the attachment efficiency of aquatic products. On the other hand, from the viewpoints of maintaining the adhesion of aquatic organisms for a long period of time and preventing particles from falling off when the aquatic organism attachment promoter of the present invention is applied to an article as a paint, it is preferable that the specific surface area of the aquatic organism attachment promoter is smaller. From these viewpoints, the specific surface area of the aquatic organism attachment promoter is, for example, 3 m 2 / g or more, 5m2 / g or more, 10m 2 / g or more, 12m 2 / g or more, or 15m 2 / g or more, for example, 50m 2 / g or less, 30m 2 / g or less, 25m 2 / g or less, 20m 2 / g or less, or 15m 2 / g or less.

[0024] From the viewpoint of handleability, a larger particle size of the aquatic organism attachment promoter of the present invention is preferable. On the other hand, from the viewpoints of increasing the surface area per mass and preventing particle detachment when the aquatic organism attachment promoter of the present invention is used by applying it to an article as a paint, a smaller particle size of the aquatic organism attachment promoter is preferable. From these viewpoints, the particle size of the aquatic organism attachment promoter may be, for example, 0.1 μm or more, 0.3 μm or more, 0.5 μm or more, 1.0 μm or more, 3.0 μm or more, 5.0 μm or more, or 10 μm or more, or may be, for example, 15 μm or less, 12 μm or less, 10 μm or less, or 8.0 μm or less.

[0025] The aquatic bioattachment promoter of the present invention comprises the rare earth ferrite described above.

[0026] The aquatic organism attachment promoter of the present invention may consist solely of rare earth ferrite, or may contain other optional components.

[0027] <Aquatic organisms> The aquatic organism attachment promoting agent of the present invention promotes the attachment of aquatic organisms selected from aquatic invertebrates and algae.

[0028] (aquatic invertebrates) The aquatic invertebrates whose attachment is promoted by the aquatic organism attachment promoter of the present invention may be, for example, one or more species selected from sponges, flatworms, annelids, tentacleds, mollusks, arthropods, protochordata, cnidarians, etc.

[0029] Porifera are, for example, sponges; Flatworms are, for example, flatworms; Annelids include, for example, Lugworms, Serpula, and Scleractinia; Tentacles are, for example, bryozoans, bryozoans, brachiopods, etc.; Mollusks are, for example, mussels, oysters, mussels, etc.; Arthropods include, for example, barnacles, sea spiders, harpacticoids, etc.; Protochordates are, for example, ascidians, amphioxus, etc.; Cnidarians are, for example, sea anemones, hydroids, etc.

[0030] (algae) The algae whose attachment is promoted by the aquatic organism attachment promoting agent of the present invention may be, for example, green algae. The attachment of brown algae is not promoted as much by the aquatic organism attachment promoting agent of the present invention.

[0031] <Method for producing an aquatic organism adhesion promoter> The method for producing the aquatic organism adhesion promoter of the present invention is not particularly limited.

[0032] The aquatic organism attachment promoter of the present invention may be produced, for example, by applying an appropriate stress to a mixture containing a rare earth source and an iron source in a predetermined ratio, pulverizing and mixing the mixture, and then calcining the mixture.

[0033] As the rare earth source, for example, oxides of the desired rare earth elements may be used, as well as bastnaesite, monazite, xenotime, etc. As the rare earth element, lanthanum is preferably used from the viewpoints of the adhesion of the resulting rare earth ferrite particles to aquatic organisms and cost. Among these, the use of La2O3 allows for the production of a highly effective and relatively inexpensive aquatic organism adhesion promoter.

[0034] The iron source may be an oxide such as FeO, Fe3O4, or Fe2O3; an oxyoxide such as FeOOH, ferrihydrite, or schwermannite; or a hydroxide such as Fe(OH)2 or Fe(OH)3. Among these, if FeOOH is used as the iron source, it has higher reactivity than Fe2O3 or the like, making it possible to calcinate at a lower temperature, and it is also possible to produce an aquatic organism attachment promoter with a smaller particle size than Fe2O3 or the like.

[0035] The ratio of the rare earth source and the iron source used may be determined appropriately to match the value of x in formula (1) for the desired aquatic bioattachment promoter.

[0036] The crushing and mixing may be dry crushing or wet crushing. The stress applied to the mixture of the rare earth source and the iron source during crushing may be, for example, frictional force, shear force, shear stress, impact force, or the like.

[0037] Examples of methods for applying the stress include wet pulverization using a ball mill, a bead mill, a paint shaker, etc. When pulverization is carried out by wet pulverization, for example, water, alcohol, etc. may be used as the liquid medium. After the mixture of the rare earth source and the iron source is pulverized and mixed by wet pulverization, the liquid medium may be removed, if necessary, by an appropriate method such as heating and drying.

[0038] The firing temperature and firing time are not particularly limited and can be set appropriately.

[0039] The firing temperature may be, for example, 600°C or more, 650°C or more, 700°C or more, 750°C or more, or 800°C or more, and may be, for example, 1,200°C or less, 1,100°C or less, 1,000°C or less, 900°C or less, 800°C or less, 750°C or less, or 700°C or less.

[0040] The firing time may be, for example, 1 hour or more, 2 hours or more, 3 hours or more, 4 hours or more, 6 hours or more, 8 hours or more, 12 hours or more, or 15 hours or more, and may be carried out for, for example, 72 hours or less, 48 hours or less, 36 hours or less, 24 hours or less, 18 hours or less, or 15 hours or less.

[0041] The ambient atmosphere during firing may be an oxidizing atmosphere, for example, firing may be performed in air.

[0042] The rare earth ferrite obtained as described above may be used as the aquatic organism attachment promoter of the present invention as it is, or may be used as the aquatic organism attachment promoter of the present invention after subjecting the rare earth ferrite to water treatment.

[0043] For example, rare earth ferrite obtained via low-temperature sintering at 800°C or less will contain LnFeO3 and Ln(OH)3. On the other hand, rare earth ferrite obtained via high-temperature sintering at, for example, above 800°C will mainly contain LnFeO3, with a reduced content of the Ln(OH)3 phase. However, by subjecting the rare earth ferrite obtained by high-temperature sintering to water treatment, it is possible to obtain a rare earth ferrite containing LnFeO3 and Ln(OH)3. Note that water treatment may also be performed on the rare earth ferrite obtained by low-temperature sintering.

[0044] The water treatment of the rare earth ferrite may be carried out by any suitable method for contacting the rare earth ferrite with water, for example, by the following contact method. a method in which liquid water is added to the rare earth ferrite, the mixture is brought into contact with the ferrite, and the mixture is stirred as necessary, and then the water is removed after the mixture is brought into contact with the ferrite; A method of supplying water vapor to rare earth ferrite and bringing it into contact with it, etc.

[0045] The rare earth ferrite may be contacted with liquid water at a temperature of, for example, 0° C. or higher, 10° C. or higher, or 20° C. or higher, and 100° C. or lower, 60° C. or lower, or 40° C. or lower. This method may be repeated until the conductivity of the treated water becomes the same as that of tap water.

[0046] The contact of the rare earth ferrite material with water vapor may be carried out at a temperature of 100°C or more, 110°C or more, or 120°C or more, and 200°C or less, 160°C or less, or 140°C or less.

[0047] In the water treatment of the rare earth ferrite, contact with liquid water and contact with water vapor may be carried out in combination.

[0048] After the water treatment, the treated product may be dried appropriately before being used as the aquatic organism attachment promoter of the present invention, if desired. This drying may be carried out at a temperature of 100°C or higher, 110°C or higher, or 120°C or higher and 200°C or lower, 160°C or lower, or 140°C or lower, for a period of 1 hour or higher, 2 hours or higher, 4 hours or higher, 6 hours or higher, or 8 hours or higher, and 72 hours or lower, 48 hours or lower, 24 hours or lower, or 18 hours or lower.

[0049] The resulting aquatic organism adhesion promoting agent may be pulverized to adjust the particle size, if necessary, before use.

[0050] 《Algae adhesion promoting composition》 According to another aspect of the present invention, there is provided an algae attachment promoting composition comprising the aquatic organism attachment promoting agent of the present invention and an aquatic invertebrate repellent.

[0051] The algae adhesion-promoting composition of the present invention, which contains an aquatic organism adhesion-promoting agent and an aquatic invertebrate repellent, inhibits the adhesion of aquatic invertebrates and promotes the adhesion of algae. Therefore, when an algae adhesion-promoting article (described below) containing the algae adhesion-promoting composition of the present invention is placed in a location where it may come into contact with water such as rivers, lakes, and oceans, the adhesion of aquatic invertebrates is inhibited and the adhesion of algae is promoted.

[0052] The aquatic invertebrate repellent contained in the algae adhesion-promoting composition of the present invention may be, for example, an organic tin compound, cuprous oxide, zinc pyrithione, copper pyrithione, organic nitrogen compound, boron compound, fluorine atom-containing polymer, silicone resin, acrylic silicone resin, etc., and one or more selected from these may be used. Among these aquatic invertebrate repellents, the organic nitrogen compound is a concept that includes nitrogen-sulfur based repellents.

[0053] The amount of aquatic invertebrate repellent contained in the algae adhesion promoting composition of the present invention may be, for example, 10 parts by mass or more, 50 parts by mass or more, 100 parts by mass or more, 120 parts by mass or more, 150 parts by mass or more, 200 parts by mass or more, or 250 parts by mass or more, relative to 100 parts by mass of the aquatic organism adhesion promoting agent, and may be, for example, 500 parts by mass or less, 400 parts by mass or less, 300 parts by mass or less, or 250 parts by mass or less. When the amount of aquatic invertebrate repellent is within this range, adhesion of aquatic invertebrates is suppressed without interfering with the algae adhesion promoting effect of the aquatic organism adhesion promoting agent.

[0054] The aquatic invertebrates whose adhesion is inhibited by the aquatic invertebrate repellent contained in the algae adhesion-promoting composition of the present invention are the same as the aquatic invertebrates whose adhesion is promoted by the aquatic organism adhesion-promoting agent, and therefore, when used in the algae adhesion-promoting composition of the present invention, the adhesion of, for example, sponges, flatworms, annelids, tentacles, mollusks, arthropods, protochordata, cnidarians, etc. is inhibited.

[0055] (algae) The algae whose adhesion is promoted by the algae adhesion promoting composition of the present invention may be, for example, green algae. The algae adhesion promoting composition of the present invention does not promote the adhesion of brown algae as much.

[0056] "paint" The present invention also provides an aquatic organism adhesion promoting paint comprising the above-described aquatic organism adhesion promoting agent, and an algae adhesion promoting paint comprising the algae adhesion promoting composition.

[0057] <Aquatic organism adhesion promoting paint> The aquatic bioadhesion promoting paint of the present invention contains an aquatic bioadhesion promoting agent.

[0058] The aquatic organism attachment-promoting paint of the present invention may contain a resin and a solvent in addition to the aquatic organism attachment promoter, and may further contain other optional components. However, the aquatic organism attachment-promoting paint may be substantially free of an aquatic invertebrate repellent, as described below. The aquatic organism attachment-promoting composition being substantially free of an aquatic invertebrate repellent means that the amount of the aquatic invertebrate repellent in the aquatic organism attachment-promoting composition is 5 parts by mass or less, 3 parts by mass or less, 1 part by mass or less, 0.5 parts by mass or less, or 0.1 parts by mass or less per 100 parts by mass of the aquatic organism attachment-promoting agent, or the aquatic organism attachment-promoting composition may be completely free of an aquatic invertebrate repellent.

[0059] The resin contained in the aquatic organism adhesion-promoting paint of the present invention forms a coating film on the surface of the article and functions as a binder for fixing the aquatic organism adhesion-promoting agent to the article. This resin may be selected from, for example, acrylic resin, acrylic silicone resin, amino alkyd resin, epoxy resin, phenolic resin, polyurethane resin, unsaturated polyester resin, fluororesin, etc. As described below, the silicone resin functions as an aquatic invertebrate repellent. Therefore, paints containing silicone resins are included in the "algae adhesion-promoting paint" described below.

[0060] The amount of resin in the aquatic organism attachment-promoting paint may be, for example, 100 parts by mass or more, 150 parts by mass or more, 200 parts by mass or more, 250 parts by mass or more, or 300 parts by mass or more, relative to 100 parts by mass of the aquatic organism attachment promoter, and may be, for example, 500 parts by mass or less, 450 parts by mass or less, 400 parts by mass or less, 350 parts by mass or less, or 300 parts by mass or less. When the amount of resin is within this range, an extremely strong coating film can be formed without interfering with the aquatic organism attachment-promoting effect. Therefore, a coating film formed from an aquatic organism attachment-promoting paint with such a blending amount can stably exhibit the aquatic organism attachment-promoting effect over a long period of time.

[0061] The solvent contained in the aquatic organism attachment-promoting paint of the present invention may be, for example, one or more selected from water, alcohols, esters, ketones, ethers, aliphatic hydrocarbons, aromatic hydrocarbons, and the like.

[0062] The solvent contained in the aquatic organism attachment-promoting paint of the present invention may in particular be an aromatic hydrocarbon, and may be, for example, one or more selected from toluene, xylene, ethylbenzene, cumene, and the like.

[0063] The amount of solvent in the aquatic organism adhesion-promoting paint of the present invention may be, for example, an amount such that the solid pigment content of the paint is 25% by mass or more, 30% by mass or more, 35% by mass or more, 40% by mass or more, or 45% by mass or more, or, for example, an amount such that the solid pigment content of the paint is 75% by mass or less, 70% by mass or less, 65% by mass or less, 60% by mass or less, 55% by mass or less, or 50% by mass or less.

[0064] Optional components that may be contained in the aquatic organism attachment-promoting paint of the present invention may be, for example, dispersants, colorants, extender pigments, defoamers, thickeners, wetting agents, preservatives, and the like.

[0065] The dispersant contained in the aquatic organism attachment-promoting paint of the present invention may be appropriately selected from known dispersants, such as acrylic acid-based, carboxylic acid-based, sulfonic acid-based, ammonium salt-based, etc. Specific examples of the dispersant include ammonium salts of acrylic copolymers and alkylol ammonium salts of copolymers having acid groups.

[0066] The amount of dispersant in the aquatic organism attachment promoting paint may be, for example, 1 part by mass or more, 3 parts by mass or more, 5 parts by mass or more, or 10 parts by mass or more, per 100 parts by mass of the aquatic organism attachment promoting agent, and may be, for example, 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, or 10 parts by mass or less.

[0067] The proportion of the aquatic organism adhesion promoter in the aquatic organism adhesion-promoting paint of the present invention may be, for example, 3 mass% or more, 5 mass% or more, 7 mass% or more, or 10 mass% or more, relative to the total mass of the aquatic organism adhesion-promoting paint, and may be, for example, 25 mass% or less, 20 mass% or less, or 15 mass% or less.

[0068] The proportion of the aquatic organism adhesion promoter in the solids content of the aquatic organism adhesion promoting paint may be, for example, 5% by mass or more, 10% by mass or more, 15% by mass or more, 20% by mass or more, or 25% by mass or more, and may be, for example, 50% by mass or less, 40% by mass or less, 35% by mass or less, 30% by mass or less, or 25% by mass or less.

[0069] The aquatic organism attachment-promoting paint of the present invention may be produced by mixing the aquatic organism attachment promoter, resin, solvent, and other optional components by any suitable means. Mixing may be carried out using a known mixer. Examples of the mixer include a ball mill, a bead mill, a planetary mixer, and a lab shaker.

[0070] <Algae adhesion promoting paint> The algae adhesion-promoting paint of the present invention comprises the above-mentioned algae adhesion-promoting composition. In other words, the algae adhesion-promoting paint of the present invention is a paint containing the above-mentioned aquatic organism adhesion-promoting agent (rare earth ferrite) and aquatic invertebrate repellent.

[0071] The description of the algae adhesion promoting composition may be applied to the blending ratio of the aquatic organism adhesion promoting agent and the aquatic invertebrate repellent in the algae adhesion promoting paint of the present invention.

[0072] The algae adhesion-promoting paint of the present invention may contain a resin and a solvent in addition to the aquatic organism adhesion-promoting agent and the aquatic invertebrate repellent, and may further contain other optional components. Here, when the aquatic invertebrate repellent contains a resinous repellent such as a fluorine atom-containing polymer, a silicone resin, or an acrylic silicone resin, the aquatic invertebrate repellent can function as a binder for the paint. Therefore, in this case, the algae adhesion-promoting paint does not need to contain any resin other than the aquatic invertebrate repellent. However, an algae adhesion-promoting paint containing a resinous repellent may further contain another resin.

[0073] The types and amounts of resins that can be contained in the algae adhesion promoting paint may be the same as those described above for the algae adhesion promoting paint. However, when the algae adhesion promoting paint contains a resinous repellent, the amount of resin should be understood as the total amount of the resinous repellent and other resins.

[0074] The explanation for the algae adhesion-promoting paint may be applied to the types and amounts of solvents and other optional components that may be contained in the algae adhesion-promoting paint. The explanation for the algae adhesion-promoting paint may also be applied to the proportion of the aquatic organism adhesion promoter in the paint, the proportion of the aquatic organism adhesion promoter in the paint solids, and the manufacturing method of the algae adhesion-promoting paint.

[0075] 《Articles》 The present invention further provides an aquatic organism adhesion promoting article comprising the above-described aquatic organism adhesion promoting agent, and an algae adhesion promoting article comprising the algae adhesion promoting composition.

[0076] <Aquatic organisms adhesion promoting article> The aquatic organism attachment-promoting article of the present invention contains the aquatic organism attachment-promoting agent of the present invention. This aquatic organism attachment-promoting article may be made of a material containing the aquatic organism attachment-promoting agent, or may be an article made of any material having a layer containing the aquatic organism attachment-promoting agent on the surface thereof.

[0077] In consideration of the use efficiency of the aquatic organism attachment promoting agent, the aquatic organism attachment promoting article may be an article made of any material, and have a layer containing the aquatic organism attachment promoting agent on the surface thereof. In this case, the layer containing the aquatic organism attachment promoting agent may be formed on a part or the entire surface of the article.

[0078] The concentration of the aquatic organism attachment promoter in the layer containing the aquatic organism attachment promoter is, for example, 10 g / m as the amount of rare earth ferrite per unit surface area of the article. 2 More than 20g / m 2 More than 25g / m 2 More than 30g / m 2 or more, or 35 g / m 2 or more, for example, 100 g / m 2 Below 80g / m 2 Below 50g / m 2 Below 45g / m 2 or less than 40 g / m 2 It may be the following:

[0079] The layer containing the aquatic organism adhesion promoting agent of the aquatic organism adhesion promoting article may be a coating of the aquatic organism adhesion promoting paint of the present invention. Formation of a coating of the aquatic organism adhesion promoting paint on the surface of an article made of any material may be carried out by a known coating method.

[0080] <Articles that promote algae adhesion> The algae adhesion promoting article of the present invention comprises the above-described algae adhesion promoting composition. In other words, the algae adhesion promoting article of the present invention is an article comprising the above-described aquatic organism adhesion promoting agent (rare earth ferrite) and aquatic invertebrate repellent.

[0081] The algae adhesion promoting article may be made from a material containing the algae adhesion promoting composition, or may be an article made from any material having a layer containing the algae adhesion promoting composition on its surface.

[0082] Considering the use efficiency of the aquatic organism adhesion promoting agent, the algae adhesion promoting article may have a layer containing the algae adhesion promoting composition on the surface of an article made of any material. In this case, the layer containing the algae adhesion promoting composition may be formed on a part or the entire surface of the article.

[0083] Regarding the concentration of the aquatic organism attachment promoting agent in the layer containing the algae attachment promoting composition, the explanation for the aquatic organism attachment promoting article may be applied.

[0084] Furthermore, the layer of the algae adhesion-promoting article containing the algae adhesion-promoting composition may be a coating of the algae adhesion-promoting paint of the present invention. Formation of a coating of the algae adhesion-promoting paint on the surface of an article made of any material may be carried out by a known coating method.

[0085] (Use of the item) The aquatic organism attachment-promoting article and algae attachment-promoting article of the present invention may be, for example, an artificial seaweed reef, an algae seedling raising sheet, an aquaculture net, an aquaculture rope, a shellfish aquaculture pipe, etc. [Example]

[0086] 1. Confirmation of the effectiveness of aquatic organism adhesion promoters and aquatic invertebrate repellents <Synthesis of aquatic biofouling promoter> La2O3 and FeOOH were weighed and charged into a ball mill using 10 mm diameter alumina balls as grinding media so that the molar ratio of La to Fe was La:Fe = 70:30, and water was added, followed by grinding and mixing for 5 hours. The resulting ground material was dried at 300°C for 15 hours and then crushed in a rotary crusher. The resulting crushed material was fired at 700°C for 15 hours and then crushed in a hammer mill to obtain lanthanum ferrite (LaFe, aquatic organism adhesion promoter).

[0087] When the obtained lanthanum ferrite was subjected to XRD analysis, a peak at about 2θ=32.1° attributed to LaFeO3 and a peak at about 2θ=27.9° attributed to La(OH)3 were observed.

[0088] The specific surface area of the obtained lanthanum ferrite measured by the BET single-point method in accordance with JIS Z8830 was 19.2 m 2 / g.

[0089] <<Preparation of evaluation samples>> Example 1 A 100 mL mayonnaise bottle was charged with 9.4 g of the lanthanum ferrite (LaFe) obtained above, 70.5 g of an acrylic resin solution (solvent: xylene, solids concentration: 40 wt%), 0.9 g of an ammonium salt-based wetting and dispersing agent "DYSPERBYK-180" (trade name, manufactured by BYK-Chemie GmbH), and 0.1 g of xylene as an additional solvent. 80 g of 3 mm diameter zirconia beads were then added and shaken for 3 hours in a paint shaker to prepare an aquatic invertebrate repellent-free aquatic organism adhesion-promoting paint. The lanthanum ferrite content in the resulting paint was 25 wt% based on the solids content of the paint. The median diameter (D50) of dispersed lanthanum ferrite particles in the resulting paint was 0.41 μm as measured by dynamic light scattering.

[0090] The paint obtained above was applied to one side of a 70mm x 150mm rectangular FRP flat plate (manufactured by Miecast Co., Ltd.) with a dry paint amount of 150g / m 2 (LaFe coating amount 37.5g / m 2 ) was applied with a brush to prepare an evaluation sample.

[0091] Example 2 The lanthanum ferrite (LaFe) synthesized above was added to a chemical-free silicone paint manufactured by Bassel Chemical Industry Co., Ltd., product name "SS Guard," so that the LaFe concentration in the coating film was 30 mass %, and the mixture was further diluted with xylene so that the paint solids content was 45 mass %. The mixture was then thoroughly stirred to prepare an algae adhesion-promoting paint containing silicone resin as an aquatic invertebrate repellent.

[0092] The paint obtained above was applied to one side of the same type of FRP flat plate as used in Example 1 in a dry paint amount of 125 g / m2 (LaFe coating amount 37.5g / m 2 ) was applied with a brush to prepare an evaluation sample.

[0093] Comparative Example 1 The same type of FRP flat plate as used in Examples 1 and 2 was used as an evaluation sample without being coated with paint.

[0094] Adhesion test The obtained evaluation samples were immersed and left to stand offshore in City A, Prefecture A. After four months had passed since the start of the test, the state of aquatic organisms attached to the samples was examined and evaluated according to the following criteria. A: Large amounts of adhesion B: A small amount of adhesion C: No adhesion

[0095] The test was conducted from October to March of the following year. The results are shown in Table 1.

[0096] [Table 1]

[0097] According to Table 1, the evaluation sample of Example 1, which was coated with a paint containing LaFe but no aquatic invertebrate repellent, had a higher amount of both aquatic invertebrates and algae attached four months after the start of the attachment test than the evaluation sample of Comparative Example 1, which was not coated with a paint. Also, the evaluation sample of Example 2, which was coated with a paint containing LaFe and an aquatic invertebrate repellent, had no aquatic invertebrates attached but a high amount of algae attached.

[0098] The amount of attached algae was less in the evaluation sample of Example 1 compared to the evaluation sample of Example 2, which is presumably because the attached aquatic invertebrates ate the algae.

[0099] These results verified that by using a paint containing the aquatic organism adhesion promoter of the present invention and selected to contain or not contain an aquatic invertebrate repellent, it is possible to selectively attract aquatic invertebrates and algae to the target object.

[0100] 2. Checking the attachment status of aquatic invertebrates <<Preparation of evaluation samples>> Example 3 In the same manner as in Example 1, an evaluation sample was prepared by applying a paint containing LaFe but not containing an aquatic invertebrate repellent.

[0101] Comparative Example 2 Similar to Comparative Example 1, an FRP plate without paint coating was used as the evaluation sample.

[0102] Adhesion test The obtained evaluation samples were immersed in different test locations and left to stand. After 40 to 50 days from the start of the test, the adhesion status of aquatic organisms was checked and evaluated according to the same criteria as in Example 1.

[0103] The test was conducted from October to March of the following year, and the results are shown in Table 2.

[0104] [Table 2]

[0105] Although the types of organisms that attached differed depending on the test location, it was verified that the amount of aquatic invertebrates attached generally increased in the evaluation sample of Example 1, which was coated with a paint containing the aquatic organism attachment promoter of the present invention. Note that, despite the expectation of ingestion by aquatic invertebrates, the amount of algae attached was high in City c, Prefecture C and City d, Prefecture D. This is thought to be due to the different types of aquatic invertebrates that attached and the fact that the amount of algae eaten by aquatic invertebrates was low due to the influence of the season in which the test was conducted.

[0106] 3. Confirmation of selective adhesion performance of algae

[0107] <Synthesis of aquatic biofouling promoter> In a ball mill using 10 mm diameter alumina balls as the grinding media, 0.4 moles of La2O3, 0.2 moles of FeOOH (La:Fe = 80:20 (molar ratio)), and water were charged and ground and mixed for 5 hours. The resulting ground product was dried at 300°C for 15 hours and then crushed in a rotary crusher. The resulting crushed product was fired at 700°C for 15 hours and then crushed in a hammer mill to obtain a crushed product.

[0108] Next, the crushed material was subjected to water treatment. In this water treatment, the crushed material obtained was placed in a washing tank, tap water was added and stirred, the treated water was removed by filtration, and then new tap water was added, followed by repeated stirring and filtration. The end point of the water treatment was the point at which the treated water and tap water had the same conductivity.

[0109] The crushed material after the water treatment was dried at 130°C for 15 hours and then crushed again with a hammer mill to obtain lanthanum ferrite (an aquatic organism adhesion promoter).

[0110] When the obtained lanthanum ferrite was subjected to XRD analysis, a peak at about 2θ=32.1° attributed to LaFeO3 and a peak at about 2θ=27.9° attributed to La(OH)3 were observed.

[0111] <<Preparation of evaluation samples>> Example 4 The aquatic organism adhesion promoter synthesized above was added to a chemical-free silicone paint manufactured by Bassel Chemical Co., Ltd., product name "SS Guard," so that the concentration of the aquatic organism adhesion promoter in the coating film was 30 mass %, and then xylene was added to dilute the paint so that the paint solids content was 45 mass % and stirred well to prepare a test paint.

[0112] A commercially available polyethylene seaweed net was immersed in the test paint prepared above, and then left to dry at room temperature for 1 day (24 hours) to prepare a test net.

[0113] Comparative Example 3 A test net was prepared in the same manner as in Example 4, except that the silicone paint "SS Guard" without the addition of an aquatic organism adhesion promoter was used as the test paint.

[0114] Comparative Example 2 The seaweed net without any test paint applied was used as the test net.

[0115] Adhesion test The test net was set up in the ocean off the coast of City E, Prefecture E, where the current is calm, and the adhesion of green and red algae was examined on the 26th, 64th, 115th, and 153rd days after installation. The test was carried out from the end of November to the beginning of April of the following year. The adhesion of algae was expressed as the adhesion area of each algae, with the area of the test net being taken as 100%. The results are shown in Table 3.

[0116] [Table 3]

[0117] In the seaweed net of Comparative Example 4, which was not coated with paint, red algae had a slight preference over green algae until the 64th day after the test net was installed, but thereafter the red algae drove out the green algae, and by the 153rd day, red algae had attached to 95% of the test net area.Furthermore, the test net of Comparative Example 3, which was coated with only silicone paint, was effective in preventing the attachment of both green and red algae, but no effect was observed in promoting the attachment of specific algae.

[0118] In contrast, it was confirmed that the test net of Example 1, which was coated with a silicone paint containing the aquatic organism adhesion promoter of the present invention, exhibited an adhesion-preventing effect against red algae as well as an adhesion-promoting effect against green algae.

[0119] 《Reference example 1》 (1) Measurement of changes in suspension pH over time 60 g of the lanthanum ferrite (LaFe, La:Fe = 70:30) obtained above was added to 200 g of pure water and stirred with a magnetic stirrer to form a suspension. Stirring with the magnetic stirrer was continued, and the pH of the suspension was measured using a portable pH meter manufactured by HORIBA, Ltd., one hour, one day (24 hours), and one month (720 hours) after adding LaFe.

[0120] The initial pH of the pure water used here was 7.3.

[0121] (2) Measurement of ion elution amount The same LaFe as above was added to 98 g of pure water and allowed to stand for 7 days (168 hours). After standing, the supernatant was sampled and subjected to inductively coupled plasma atomic emission spectroscopy (ICP-AES) under the following conditions to quantify the amount of La ions in the supernatant. Measurement equipment: Shimadzu Corporation, inductively coupled plasma optical emission spectrometer, model "ICPS-8100" Transmission method: Free running Transmission frequency: 27MHz ±1MHz Rated output: 0.8~1.6kW First spectrometer: 1m Czerny-Turner mounting Diffraction grating: 4,960 lines / mm Wavelength range: 160~372nm Second spectrometer: 1m Czerny-Turner mounting Diffraction grating: 4,320 lines / mm Wavelength range: 250~426nm

[0122] Comparative Example 1 Assuming that the procedure was the same as in Reference Example 1, except that commercially available calcium hydroxide was used instead of LaFe in Reference Example 1, the pH of the suspension after 1 hour, 1 day (24 hours), and 1 month (720 hours), as well as the amount of Ca ion elution after standing for 7 days (168 hours), were each determined by theoretical calculation.

[0123] The above results are shown in Table 4.

[0124] [Table 4]

[0125] When commercially available calcium hydroxide was added to water, a large amount of Ca ions were released into the water, causing the pH of the water to rise rapidly. However, it was confirmed that LaFe released only a small amount of La ions into the water and had the ability to gradually increase the pH of the water.

[0126] It is presumed that these properties of LaFe are involved in the long-term expression of the aquatic organism adhesion promoting function of the aquatic organism adhesion promoting agent of the present invention, although the present invention is not limited to any particular theory.

Claims

1. Contains rare earth ferrite, Used for the selective attachment of aquatic organisms selected from aquatic invertebrates and algae, Aquatic biofouling promoter.

2. The rare earth ferrite has the following formula (1): Ln ２ｘ Fe ２（１－ｘ） O ３ (1) (In formula (1), Ln is a rare earth element selected from the group consisting of lanthanum, praseodymium, neodymium, and yttrium, and x is a number equal to or greater than 0.50 and less than 1.00.) The aquatic organism adhesion promoter according to claim 1, having a composition represented by the formula:

3. The aquatic organism adhesion promoter according to claim 2, wherein x in formula (1) is a number of 0.65 or more and 0.85 or less.

4. 2. The aquatic bioattachment promoter according to claim 1, wherein the rare earth ferrite is lanthanum ferrite.

5. The aquatic organism adhesion promoter according to claim 2, wherein Ln in formula (1) is lanthanum.

6. The aquatic invertebrate is one or more selected from sponges, flatworms, annelids, tentacles, mollusks, arthropods, protochordates, and cnidarians. The aquatic organism adhesion promoter according to any one of claims 1 to 5.

7. The aquatic organism adhesion promoting agent according to any one of claims 1 to 5, wherein the algae is green algae.

8. An algae adhesion promoting composition comprising the aquatic organism adhesion promoting agent according to any one of claims 1 to 5 and an aquatic invertebrate repellent.

9. The algae adhesion promoting composition according to claim 8, wherein the aquatic invertebrate repellent is one or more selected from organic tin compounds, cuprous oxide, zinc pyrithione, copper pyrithione, organic nitrogen compounds, boron compounds, fluorine atom-containing polymers, and silicone resins.

10. The algae attachment promoting composition of claim 8 , wherein the algae is green algae.

11. The algae attachment promoting composition of claim 9, wherein the algae is green algae.

12. An aquatic organism adhesion promoting paint comprising the aquatic organism adhesion promoting agent according to any one of claims 1 to 5.

13. An aquatic organism adhesion promoting article comprising the aquatic organism adhesion promoting agent according to any one of claims 1 to 5.

14. An algae adhesion-promoting paint comprising the aquatic organism adhesion-promoting agent according to any one of claims 1 to 5 and an aquatic invertebrate repellent.

15. An algae adhesion promoting article comprising the aquatic organism adhesion promoting agent according to any one of claims 1 to 5 and an aquatic invertebrate repellent.

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