TW202404900A - Rare earth ferrite particles and rare earth ferrite dispersion liquid - Google Patents

Abstract

Rare earth ferrite particles according to the present invention are represented by the following formula (1): Ln2xFe2(1-x)O3 (where Ln is a rare earth element selected from the group consisting of lanthanum, praseodymium, neodymium, and yttrium, and x is a number from 0.45 or greater to less than 1.00). The rare earth ferrite particles, in a volume cumulative distribution of particle size distribution, comprises small particles and large particles, the small particles having a particle size within the range from 0.01 to 1.0 [mu]m, and the large particles having a particle size within the range from greater than 1.0 [mu]m to less than or equal to 17.0 [mu]m. The volume ratio of the small particles in relation to the total volume of the small particles and the large particles is from 10 volume% to 90 volume%.

Description

Rare earth fertilizer granular iron particles and rare earth fertilizer granular iron dispersion liquid

The present invention relates to rare earth fertilizer iron particles and a rare earth fertilizer iron dispersion liquid.

In recent years, various items that have been treated with antibacterial processing, antifungal processing, etc. from the viewpoint of hygiene are being circulated. Antibacterial and anti-mildew items are not limited to items used directly by consumers. For example, the demand for anti-bacterial and anti-mildew products is gradually increasing for exterior and interior walls of buildings, building materials, air filters, gaskets, etc.

Agents that exhibit antibacterial effects are known to include: phenol-based, organotin-based, trisulfonate-based, halogenated sulfonylpyridine-based, captan-based, organic copper-based, chloronaphthalene-based, and chlorophenylpyridazine-based agents and other compounds (see Patent Document 1).

In addition, ions showing antibacterial effects are known to include silver ions, copper ions, zinc ions, etc. These ions are, for example, metal powders of silver, copper, zinc, etc., or alloys and compounds thereof, which are used in a state of being retained in a carrier, and trace amounts of these metal ions are eluted, thereby utilizing their toxicity. Patent Document 2 discloses a dispersion having deodorizing, antibacterial, and antifungal properties in which a carboxylic acid metal salt composed of a carboxyl group-containing polymer and a metal compound is dispersed.

However, recent antibacterial agents in the form of pharmaceuticals and antibacterial agents that utilize the toxicity of metal ions are sometimes considered to be problematic in terms of their environmental pollution and safety.

In addition, in recent years, fertilized iron compounds have been proposed as anti-algae agents with low environmental pollution and excellent safety. For example, Patent Documents 3 and 4 each disclose orthoferrite containing a rare earth element selected from the group consisting of lanthanum (La), phosphorus (Pr), neodymium (Nd), and yttrium (Y), iron, and oxygen. The main component is an anti-algae additive, an anti-algae paint using the same, and an anti-algae product that coats the paint on the surface of a substrate. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. Sho 63-17249 [Patent Document 2] Japanese Patent Application Laid-Open No. 2-288804 [Patent Document 3] Japanese Patent Application Publication No. 2005-272320 [Patent Document 4] International Publication No. 2021/193644

[Problem to be solved by the invention]

In Patent Document 3, it is believed that the anti-algae effect is related to the magnetism of the material, and it is stated that the coercive force is small and the rare earth oxide exhibits a magnetic force close to the inherent magnetic field of the plant: Fe ₂ O ₃ =1:1 (Molar ratio) positive Ferrite is most suitable as an anti-algae additive.

In addition, Patent Document 4 discusses the anti-algae effect of lanthanum-rich orthoferrite.

However, Patent Documents 3 and 4 do not discuss the antifungal effect and antibacterial effect of orthoferrite.

Generally speaking, if mold occurs on an item, bacteria will often be produced along with the mold. Therefore, there is a need for anti-mold and antibacterial agents that can inhibit the occurrence of mold and have sterilizing effects. However, in the conventional technology, no antifungal and antibacterial agents are known that are highly effective against both mold and bacteria.

The present invention is made in view of the above background. The object of the present invention is to provide an antifungal and antibacterial compound with low environmental pollution and excellent safety, and a coating liquid for forming a coating film of the antifungal and antibacterial compound on the surface of an article. [Means to solve the problem]

The inventors of this case have conducted intensive research in order to solve the above-mentioned problems. Furthermore, it was discovered that rare earth fertilizer iron particles with a specific composition and specific particle size distribution can be used as an antifungal and antibacterial agent with low environmental pollution and excellent safety, leading to the completion of the present invention. That is, the present invention is as follows.

≪Aspect 1≫A rare earth fertilizer iron particle is represented by the following formula (1): In formula (1), Ln is a rare earth element selected from the group consisting of lanthanum, chromium, neodymium, and yttrium, and x is a number between 0.45 and less than 1.00; the aforementioned rare earth fertilizer iron particles have a particle size distribution The cumulative volume distribution contains small-sized particles and large-sized particles; the aforementioned small-sized particles are particles in the range of 0.01 to 1.0 μm; the aforementioned large-sized particles are particles with a diameter exceeding 1.0 μm and 17.0 μm Particles within the following range; and the ratio of the volume of the aforementioned small particle size particles to the total volume of the aforementioned small particle size particles and the aforementioned large particle size particles is not less than 10 volume % and not more than 90 volume %. ≪Aspect 2≫Rare earth fertilizer iron particles as in Aspect 1, wherein the ratio of the volume of the small particle size particles to the total volume of the small particle size particles and the large particle size particles exceeds 50% by volume And less than 75% by volume. ≪Aspect 3≫Rare earth fertilizer iron particles as in aspect 1 or 2, wherein the ratio of the total volume of the small particle size particles and the large particle size particles to the total volume of the rare earth fertilizer iron particles is, It is more than 75% by volume. ≪Aspect 4≫Rare earth fertilizer iron particles as in any one of aspects 1 to 3, wherein the d50 particle size of the aforementioned small particle size particles is 0.05~0.50 μm; the d50 particle size of the aforementioned large particle size particles is 0.05~0.50 μm; 1.1~5.0μm or less. ≪Aspect 5≫Rare earth fertilizer iron particles as in any one of aspects 1 to 4, wherein the aforementioned small particle size particles are particles in the range of 0.10 to 0.50 μm; and the aforementioned large particle size particles , are particles with a particle size in the range of 1.0~5.0μm or less. ≪Aspect 6≫The rare earth fertilized iron particles according to any one of aspects 1 to 5, wherein x in the aforementioned formula (1) is a number ranging from 0.65 to 0.85. ≪Aspect 7≫The rare earth fertilized iron particles according to any one of aspects 1 to 6, wherein Ln in the aforementioned formula (1) is lanthanum. ≪Aspect 8≫A rare earth fertilizer iron dispersion liquid containing the rare earth fertilizer iron particles according to any one of aspects 1 to 7, a resin, and a solvent. ≪Aspect 9≫A mold-proof and antibacterial article having a coating containing rare earth fertilizer iron particles as in any one of aspects 1 to 7. ≪Aspect 10≫Anti-mildew and antibacterial articles such as aspect 9, which are utensils, curtains, door handles, partitions, films for preventing droplets, protective films for smartphones, protective films for touch panels, and masks , train hanging rings, packaging materials, general printed matter, business forms, banknotes, securities, cards, home appliances, air conditioner-related components, toys, building interiors, building exteriors, automobile interiors, train interiors, or aircraft Interior. ≪Aspect 11≫For example, the anti-mold and antibacterial articles in aspect 10 are transparent partitions, transparent droplet prevention films, protective films for smartphones, or protective films for touch panels. [Effects of the invention]

According to the present invention, it is possible to provide an antifungal and antibacterial compound with low environmental pollution and excellent safety, and a coating liquid for forming a coating film of the antifungal and antibacterial compound on the surface of an article.

≪Rare earth fertilizer iron particles≫

The rare earth fertilizer iron particles of the present invention are rare earth fertilizer iron particles and are represented by the following formula (1): In formula (1), Ln is a rare earth element selected from the group consisting of lanthanum, chromium, neodymium, and yttrium, and x is a number above 0.45 but not up to 1.00; In the cumulative volume distribution of the particle size distribution, small particles are included Small-sized particles and large-sized particles; The aforementioned small-sized particles are particles in the range of 0.01 to 1.0 μm in diameter; The aforementioned large-sized particles are particles in the range of more than 1.0 μm and less than 17.0 μm; and The ratio of the volume of the small-diameter particles to the total volume of the small-diameter particles and the large-diameter particles is 10 volume % or more and 90 volume % or less.

In this specification, "particle" does not mean a single particle, but means an "aggregation of particles" showing a specific particle size distribution. Therefore, the word "particle" in this specification can mostly be interchanged with "powder".

The inventors of this case conducted a detailed study on the composition and particle size of rare earth fertilizer iron particles and their antibacterial effects. As a result, they found that by setting the rare earth (Ln):Fe ratio and the particle size in the rare earth fertilized iron to the above ranges, it was possible to achieve both a high antifungal effect and a high antibacterial effect.

The rare earth fertilizer iron particles of the present invention include small-diameter particles that are an aggregation of particles with a particle diameter in the range of 0.01 to 1.0 μm, and an aggregation of particles with a particle diameter in the range of more than 1.0 μm and 17.0 μm or less. large-sized particles.

The rare earth fertilizer iron particles in conventional technology contain many coarse particles. When a coating film containing the rare earth iron particles of the conventional technology is formed, the coarse rare earth iron particles in the coating film are spaced apart from each other and become larger than the size of mold and bacteria. Therefore, even if there are mold or bacteria close to the coarse rare earth iron particles, there will still be many that are not in contact with the rare earth iron particles, making it difficult to achieve the desired antifungal and antibacterial properties.

In contrast, the rare earth fertilizer iron particles of the present invention contain small-sized particles close to the size of bacteria, and large-sized particles close to the size of mold. Additionally, certain embodiments of the present invention reduce the proportion of coarse particles that are significantly larger than the size of bacteria and mold.

Therefore, in the coating film containing the rare earth iron particles of the present invention, the intervals between the rare earth iron particles are mainly composed of parts that are the same size as mold and parts that are the same size as bacteria. Therefore, even if mold approaches or bacteria approaches the coating film containing the rare earth fertilizer iron particles of the present invention, the probability of contact with the rare earth fertilizer iron particles in the coating film will increase, thereby achieving the desired prevention effect. Mildew and antibacterial properties.

Therefore, the rare earth fertilizer iron particles of the present invention are extremely suitable as antifungal and antibacterial agents.

The rare earth fertilizer iron particles of the present invention may be in any form as long as x in the above formula (1) is a number of 0.45 or more and less than 1.00. For example, it may be a solid solution with a uniform composition as a whole, a mixture of the LnFeO ₃ phase and the Ln ₂ O ₃ phase, or a mixture of a solid solution with a uniform composition and the LnFeO ₃ phase and the Ln ₂ O ₃ phase. . In addition, it may also contain phases other than these.

x in formula (1) can also be above 0.50, above 0.55, above 0.60, above 0.65, above 0.70, or above 0.75, or below 0.90, below 0.85, below 0.80, below 0.75, below 0.70, below 0.65 , or below 0.60.

Generally speaking, x in the above formula (1) can be, for example, a number from 0.50 to 0.90, furthermore, it can be a number from 0.65 to 0.85, and particularly, it can be a number from 0.70 to 0.80.

The rare earth (Ln) in the formula (1) can be especially lanthanum from the viewpoint of mildew resistance, antibacterial properties and cost. Therefore, the antifungal and antibacterial agent of the present invention can also be lanthanum fertilized iron particles.

The rare earth fertilizer iron particles of the present invention contain small-sized particles and large-sized particles in the cumulative volume distribution of the particle size distribution.

The above-mentioned particle size distribution is measured by dynamic light scattering after adding rare earth fertilizer iron particles in a dry powder state and dispersing them in an aqueous solution of sodium hexametaphosphate with a concentration of 0.2% by weight.

＜Small size particles＞ Small particle size particles are an aggregate of particles with a particle size in the range of 0.01 to 1.0 μm in the cumulative volume distribution of the particle size distribution.

The particle size range of the small particle size particles may be 0.02 μm or more, 0.03 μm or more, or 0.05 μm or more, or may be 0.9 μm or less, 0.8 μm or less, or 0.7 μm or less. The particle size range of the small particle size particles may be, for example, 0.1~0.5 μm.

For small-size particles, the 50% diameter (d50 particle size) in the cumulative volume distribution of the particle size distribution can also be 0.05~0.50 μm. By setting the d50 particle size of the small particle size particles within this range, the small particle size particles will contain many particles close to the size of bacteria, and the antibacterial properties of the rare earth fertilizer iron particles will be further improved.

The d50 particle size of small particle size particles can be 0.08 μm or more, 0.10 μm or more, 0.12 μm or more, 0.15 μm or more, or 0.18 μm or more, or it can be 0.45 μm or less, 0.40 μm or less, 0.35 μm or less, or 0.30 μm or less. , or below 0.25μm.

＜Large diameter particles＞ Large particle size particles are an aggregate of particles with a particle size ranging from more than 1.0 μm to less than 17.0 μm in the cumulative volume distribution of the particle size distribution.

The particle size range of the large particle size particles may be 1.1 μm or more, 1.3 μm or more, 1.5 μm or more, 1.8 μm or more, or 2.0 μm or more, or it may be 15.0 μm or less, 13.0 μm or less, 10.0 μm or less, or 8.0 μm. or less, 5.0μm or less, or 4.5μm or less. The particle size range of the large particle size particles may be, for example, 1.1 to 5.0 μm.

For large particle size particles, the 50% diameter (d50 particle size) of the cumulative volume distribution of the particle size distribution can also be 1.1~5.0 μm. By setting the d50 particle size of the large particle size particles within this range, the large particle size particles will contain many particles close to the size of mold, and the mildew resistance of the rare earth fertilizer iron particles will be further improved.

The d50 particle size of large particle size particles can be 0.8 μm or more, 1.0 μm or more, 1.2 μm or more, or 1.5 μm or more, or it can be 4.5 μm or less, 4.0 μm or less, 3.5 μm or less, 3.0 μm or less, or 2.5 μm or less. , or below 2.0μm.

＜Existence ratio of small-sized particles to large-sized particles＞ The ratio of the volume of the small-diameter particles to the total volume of the small-diameter particles and the large-diameter particles may be 10 volume % or more and 90 volume % or less. The ratio of the volume of small particle size particles to the total volume of small particle size particles and large particle size particles may be 20 volume % or more, 30 volume % or more, 40 volume % or more, 50 volume % or more, or more than 50 volume %. 60 volume % or more, or 70 volume % or more, or 80 volume % or less, 75 volume % or less, 70 volume % or less, or 60 volume % or less.

When mold or bacteria come close to the coating film containing the rare earth fertilizer iron particles of the present invention, it is considered that the probability of contact between the smaller bacteria and the rare earth fertilizer iron particles is low. Therefore, from the viewpoint of ensuring a good balance between mildew resistance and antibacterial properties, it is ideal to contain more small particle size particles that contribute significantly to antibacterial properties than large particle size particles.

From this point of view, the ratio of the volume of the small particle size particles to the total volume of the small particle size particles and the large particle size particles may be more than 50 volume %, 60 volume % or more, or 70 volume % or more, for example, It may also be more than 50 volume % and 75 volume % or less.

＜The ratio of small-sized particles to large-sized particles in rare earth fertilizer iron particles＞ It is thought that the rare earth fertilizer iron particles of the present invention contain small-diameter particles and large-diameter particles. Among them, the small-diameter particles contribute greatly to antibacterial properties, and the large-diameter particles contribute greatly to antifungal properties.

Therefore, particles other than these sizes, that is, tiny particles with a particle size significantly smaller than the size of bacteria, and coarse particles with a particle size significantly larger than the size of mold, are as few as possible, which represents a high degree of prevention. It is ideal from the viewpoint of mold resistance and antibacterial properties.

From this point of view, the ratio of the total volume of small particle size particles and large particle size particles to the total volume of rare earth fertilizer iron particles can be 75 volume % or more, 80 volume % or more, 85 volume % or more, 90 volume % or more. Volume % or more, or 95 volume % or more, or 100 mass %.

≪Production method of rare earth fertilizer iron particles≫ The method for producing the rare earth fertilizer iron particles of the present invention is not particularly limited.

However, the rare earth fertilizer iron particles of the present invention can be produced, for example, by a method including the following steps: Synthesize rare earth fertilizer granular iron of desired composition (rare earth fertilizer granule iron synthesis steps); Crush the obtained rare earth fertilized iron particles to obtain large particle size particles (large particle size particle preparation step); The obtained rare earth fertilized iron particles are pulverized to obtain small-diameter particles (small-diameter particle preparation step); and large-diameter particles and small-diameter particles are mixed at a predetermined ratio (mixing step).

The above-mentioned preparation steps of large-diameter particles and small-diameter particles can be performed in different orders.

Hereinafter, each step of the method for producing the rare earth fertilizer iron particles of the present invention will be described in order.

＜Synthesis Steps of Rare Earth Fertilizer Granular Iron＞ The step of synthesizing rare earth fertilizer granules is to synthesize rare earth fertilizer granules of desired composition.

Synthesis of rare earth fertilized iron particles can be performed, for example, by applying an appropriate stress to a mixture containing a rare earth source and an iron source at a predetermined ratio, pulverizing and mixing (first pulverizing), and then calcining the mixture.

As the rare earth source, for example, oxides of desired rare earth elements can be used. In addition, bastnasite, monazite, xenotime, etc. can also be used. As the rare earth element, lanthanum is preferably used from the viewpoint of the antibacterial properties of the obtained rare earth fertilizer iron particles and the cost. Among them, if La ₂ O ₃ is used, it is possible to produce lanthanum fertilizer granular iron particles that are highly effective and relatively cheap.

As an iron source, oxides such as FeO, Fe ₃ O ₄ , and Fe ₂ O ₃ can be used; oxyhydroxides such as FeOOH, ferrihydrite, and "Schwertmannite"; Fe(OH) ₂ , Fe(OH) ₃ and other hydroxides, etc. Among these, if FeOOH is used as the iron source, since it has higher reactivity than Fe ₂ O ₃ and the like, it becomes possible to calcine at a low temperature. In addition, compared to Fe ₂ O ₃ and the like, it can be produced with a smaller particle size. of rare earth fertilizer iron particles.

The usage ratio of the rare earth source and the iron source can be appropriately determined to suit the value of x in the formula (1) of the desired rare earth fertilizer iron particles.

The grinding and mixing (first grinding) may be dry grinding or wet grinding. The stress applied to the mixture of the rare earth source and the iron source during the first crushing may be, for example, friction force, shear force, shear stress, impact force, etc. and

An example of a method of applying the stress is wet grinding in a ball mill. When the first grinding is carried out by wet grinding, as the liquid medium, for example, water, alcohol, etc. can be used. After the mixture of the rare earth source and the iron source is pulverized and mixed by wet pulverization, if necessary, the liquid medium can be removed by an appropriate method such as heating and drying, and then calcined.

The calcination temperature and calcination time are not particularly limited and can be set appropriately.

The calcination temperature may be, for example, 700°C or higher, 800°C or higher, 900°C or higher, or 1,000°C or higher, and, for example, 1,300°C or lower, 1,200°C or lower, 1,100°C or lower, or 1,000°C or lower.

The calcination 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 72 hours or less, 48 hours or less, 36 hours or more. hours, 24 hours, 18 hours, or 15 hours.

The surrounding environment during calcination can be an oxidizing environment, for example, calcination can be performed in air.

The steps for synthesizing rare earth fertilizer granules can be as described above to obtain rare earth fertilizer granules.

Before supplying the obtained rare earth fertilized iron particles to the next step, the calcined product can be cleaned if necessary. This cleaning can be performed by immersing the rare earth fertilized iron particles in an appropriate liquid medium such as water or alcohol, and extracting and removing impurities in the liquid medium. Before cleaning, the rare earth fertilizer particles can also be roughly crushed by legal methods to make cleaning easier.

＜Preparation steps of large particle size particles＞ In the large-diameter particle preparation step, the obtained rare earth fertilized iron particles are pulverized (second pulverization) to obtain large-diameter particles.

The stress exerted on the rare earth fertilized iron particles in the second crushing in the large particle size particle preparation step may be, for example, friction force, shear force, shear stress, impact force, etc. A method of applying such stress may include, for example, dry grinding in a hammer mill.

Through this second crushing, large-diameter particles are obtained. The obtained large particle size particles are supplied to the mixing step. The obtained large particle size particles can also be supplied to the mixing step after being classified as necessary.

＜Preparation steps of small particle size particles＞ The small particle diameter particle preparation step is to pulverize the obtained rare earth fertilized iron particles (third grinding) to obtain small particle diameter particles.

The stress exerted on the rare earth fertilized iron particles in the third crushing of the small particle size particle preparation step may be, for example, friction force, shear force, shear stress, impact force, etc. In order to apply such stress to the calcined material, for example, an appropriate crushing device such as a ball mill, a bead mill, a paint shaker, or a planetary mixer can be used.

For the third crushing, you can add the calcined material and liquid medium to the stirring device, as well as the dispersant as needed, and use the appropriate amplitude and vibration frequency for an appropriate time. At this time, appropriate grinding media corresponding to the grinding device can also be used. The grinding medium is, for example, balls from a ball mill, beads from a bead mill, beads from a paint shaker, etc.

The liquid medium can be, for example, water, alcohol, ester, etc.

The dispersing agent may be appropriately selected from known dispersing agents such as acrylic acid type, carboxylic acid type, sulfonic acid type, and ammonium salt type, for example. Specific examples of the dispersant include ammonium salts of acrylic copolymers and hydroxyalkyl ammonium salts of copolymers having acidic groups.

The usage amount of the dispersant is arbitrary. For example, it may be 5 parts by mass or more and 200 parts by mass or less based on 100 parts by mass of the rare earth fertilizer granular iron.

Before performing the above-mentioned third grinding, you may also perform the same grinding as the second grinding in the large-diameter particle preparation step. In addition, it is also a suitable embodiment of the present invention to supply part of the large-diameter particles obtained in the large-diameter particle preparation step to the small-diameter particle preparation step.

In the above manner, a dispersion containing small-sized particles will be obtained. The obtained dispersion is supplied to the mixing step after removing the liquid medium and the grinding medium. The obtained small particle size particles can also be supplied to the mixing step after being classified as necessary.

＜Mixing step＞ The mixing step is to mix large particle size particles and small particle size particles at a predetermined ratio. Thereby, rare earth fertilized iron particles having a desired particle size distribution can be obtained.

The mixing of large particle size particles and small particle size particles can be carried out by known methods.

≪Rare earth fertilizer granular iron dispersion≫ According to another aspect of the present invention, a dispersion liquid of rare earth fertilizer granular iron can be provided.

The rare earth fertilized iron dispersion of the present invention contains the rare earth fertilized iron particles of the present invention, a resin, and a solvent, and may further contain a dispersant.

The rare earth iron particles contained in the rare earth iron dispersion of the present invention are the rare earth iron particles of the present invention, and the above description can be directly quoted.

The resin contained in the rare earth fertilized iron dispersion of the present invention forms a coating film on the surface of the article and functions as a binder for fixing the rare earth fertilized iron particles to the article. The resin may be one that is soluble in the solvent of the rare earth fertilizer iron dispersion liquid or has good dispersibility.

The resin, for example, can be selected from the group consisting of acrylic resin, acrylic silicone resin, silicone resin, amino alkyd resin, epoxy resin, phenolic resin, polyurethane resin, unsaturated polyester resin, fluorine resin, and the like.

The dispersant used in the second grinding when producing the rare earth fertilizer iron particles of the present invention can be appropriately selected from those exemplified above.

The solvent may be one or more selected from water, alcohol, ester, ketone, ether, aromatic hydrocarbon, etc., for example.

The content of rare earth iron particles in the rare earth iron iron dispersion of the present invention, from the perspective of achieving a high balance between antibacterial properties and coating film formation properties, is determined by the total solids of the rare earth iron iron dispersion. When the ingredient content is set to 100% by mass, it may be 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, or it may be 60% by mass or less, 55% by mass or less. 50 mass% or less, 45 mass% or less, or 40 mass% or less.

In the rare earth iron dispersion of the present invention, the ratio of the rare earth iron particles to the total mass of the rare earth iron particles and the resin achieves high antibacterial properties and the effect of the rare earth iron particles on the coating film. From the viewpoint of the balance of good fixation, it may be 10 mass% or more, 12 mass% or more, 15 mass% or more, 18 mass% or more, or 20 mass% or more, or it may be 50 mass% or less, 45 mass% or less. Mass% or less, 40 mass% or less, or 35 mass% or less.

The content of the dispersant in the rare earth fertilizer iron dispersion liquid of the present invention can be 5 parts by mass or more, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more relative to 100 parts by mass of the rare earth fertilizer iron particles. , more than 25 parts by mass, or more than 30 parts by mass, or less than 200 parts by mass, less than 175 parts by mass, less than 150 parts by mass, less than 120 parts by mass, less than 100 parts by mass, less than 80 parts by mass, less than 75 parts by mass, Or less than 60 parts by mass.

≪Production method of rare earth fertilizer granular iron dispersion≫ The rare earth fertilizer granular iron dispersion of the present invention can be produced by any method as long as it has the above composition.

The rare earth fertilizer granular iron dispersion of the present invention can be produced, for example, by mixing the above-mentioned components. The components of the rare earth fertilizer granular iron dispersion can be mixed using appropriate devices such as ball mills, bead mills, paint shakers, and planetary mixers.

≪Moldproof and antibacterial items≫ According to yet another aspect of the present invention, antifungal and antibacterial articles can be provided.

The antifungal and antibacterial articles of the present invention have a coating film containing the rare earth fertilizer iron particles of the present invention. This coating film can be formed on the surface of any article.

The coating film of the antifungal and antibacterial article of the present invention may also contain resin, dispersant, etc., in addition to the rare earth fertilizer iron particles of the present invention. These resins and dispersants can be appropriately selected from the resins and dispersants contained in the rare earth fertilizer granular iron dispersion of the present invention. The usage ratio of the rare earth fertilizer iron particles, resin, and dispersant in the coating film of the antifungal and antibacterial article of the present invention can also be the same as that in the rare earth fertilizer iron particle dispersion liquid of the present invention.

The thickness of the coating film of the antifungal and antibacterial article of the present invention may be 1 μm or more, 5 μm or more, or 10 μm or more, or it may be 100 μm or less, 50 μm or less, or 20 μm or less.

The ratio of rare earth fertilizer iron particles contained in the coating film of the antifungal and antibacterial article of the present invention can be 0.1g/ ^m2 or more, 1g/m2 or ^more , or 10g/m2 ^or more per unit surface area of the article. , it can also be 50g/ ^m2 or less, 40g/ ^m2 or less, 30g/ ^m2 or less, or 20g/ ^m2 or less.

＜Mold-proof properties of anti-mold and anti-bacterial items＞ The anti-mold and antibacterial articles of the present invention will exhibit excellent anti-mold properties. Specifically, the mold suspension is coated on the coated surface of the anti-mold and antibacterial article of the present invention, and the mold area after being left to culture for 45 days in a room temperature environment is less than 12% of the area of the coated surface. , below 10%, below 8%, or below 7%, extremely low.

＜Antimicrobial properties of anti-mold and antibacterial items＞ The anti-mold and antibacterial articles of the present invention will exhibit excellent antibacterial properties. Specifically, the ATP reduction rate in the antibacterial evaluation by the "wiping method" can be 60% or more, 65% or more, 70% or more, 75% or more, 80% or more, 85% or more, or 90% or more. , or above 95%.

The "wiping method" refers to a test to investigate the degree of inhibiting the growth of bacteria in an environment with relatively low humidity and close to a normal living environment.

The "wiping method" is to cover a petri dish with filter paper moistened with water, place a test piece (an anti-mold and antibacterial article with a coating) on the filter paper, add drops of milk, for example, to the test piece and cover it with The state of the petri dish is left in a constant temperature and humidity chamber for 24 hours to deliberately allow bacteria to multiply. The test piece taken out after 24 hours was wiped with ATP wiping test reagent, and the amount of bacteria attached to the test reagent was measured as the amount of ATP (adenosine triphosphate) luminescence.

On the other hand, an article without a coating film was used as a reference sample, and bacterial growth and bacterial load were measured in the same manner as above.

Furthermore, the numerical value expressed as a percentage is the reduction rate of the bacterial load of the test piece compared with the bacterial load of the reference sample, and is evaluated as "ATP reduction rate".

The antibacterial property test by the "swabbing method" can be performed specifically by the method shown in the Examples mentioned later.

Antibacterial articles in the conventional technology will show high antibacterial properties when evaluated by the "film adhesion method" which is a general antibacterial test method, but when evaluated by the "wiping method", they will become antibacterial. The evaluation results of low sex. In comparison, the antifungal and antibacterial articles of the present invention still show excellent antibacterial properties even when evaluated by the "film adhesion method", and also show particularly good antibacterial properties when evaluated by the "wiping method". Excellent antibacterial properties.

"Film sealing method" is a test in an environment with a lot of moisture. The test is conducted under the condition that the surface of the article is covered with a water film. Therefore, it is believed that bacteria approaching the object will not reach the surface of the object and will be killed by the antibacterial ingredients leached from the object. On the other hand, the "wiping method" is a test in an environment with little moisture. It is believed that bacteria approaching the item will reach and contact the surface of the item and be killed by the antibacterial ingredients in the item.

Most of the antibacterial articles in the conventional technology are antibacterial component-eluting type. In the "film sealing method" in an environment with high moisture, the antibacterial component will dissolve and kill bacteria. However, it is considered that the "wiping method" in an environment with little moisture makes it difficult for antibacterial ingredients to elute, so it is difficult to express antibacterial properties.

In contrast, in the antifungal and antibacterial article of the present invention, small-diameter rare-earth fertilizer iron particles that are antibacterial components are fixed in the coating film. Therefore, the "film sealing method" in an environment with a lot of moisture will hinder the access and contact of bacteria on the surface of the article by the water film, so the antibacterial properties will be slightly impaired. However, the "wiping method" in an environment with low moisture will not hinder the access and contact of bacteria on the surface of the object, so it will show a high degree of antibacterial properties.

＜Use of anti-mold and antibacterial items＞ As mentioned above, the "wiping method" is a test to investigate the degree of inhibiting the growth of bacteria in an environment with relatively low humidity and close to a normal living environment. Therefore, the anti-mold and anti-bacterial articles of the present invention, which exhibit excellent antibacterial properties in this "wiping method" and also have excellent anti-mold properties, are suitable for use in environments close to normal living environments. The anti-mold and antibacterial articles of the present invention are suitable for use in, for example, home entrances, living rooms, kitchens, restaurants, bedrooms, corridors, etc.; corporate receptions, offices, conference rooms, reception rooms, corridors, lounges, restaurants, etc. ; Items used in public transportation ticket machines, ticket gates, waiting rooms, platforms, cars and other environments close to normal living environments.

The anti-mold and antibacterial articles of the present invention can be selected from, for example, utensils, curtains, door handles, partitions, films for preventing droplets, protective films for smartphones, protective films for touch panels, masks, and hanging rings for trains. , packaging materials, general printed matter, business forms, banknotes, securities, cards, home appliances, air conditioner related components, toys, building interiors, building exteriors, automobile interiors, tram interiors, aircraft interiors, etc.

The rare earth fertilizer iron particles contained in the coating film of the antifungal and antibacterial articles of the present invention are tiny particles with a 50% diameter (d50 particle diameter) of 17.0 μm or less. They are transparent due to the low degree of scattering of visible light. Excellent performance and low haze value. Therefore, the antifungal and antibacterial articles of the present invention will not damage the color tone of the article before the coating film is formed, but can exhibit a high degree of antifungal and antibacterial properties.

In particular, among the antifungal and antibacterial articles of the present invention, if the article before the coating film is formed is transparent, the transparency of the article before the coating film is formed will not be impaired, and a high degree of mildew resistance can be expressed. , antibacterial properties.

Therefore, the antifungal and antibacterial articles of the present invention may be articles requiring transparency. Specifically, for example, they may be selected from the group consisting of transparent partitions, transparent droplet prevention films, protective films for smartphones, and touch panels. Protective film, etc.

≪Methods for manufacturing anti-mold and antibacterial articles≫ The antifungal and antibacterial article of the present invention can be produced by any method as long as it has the above-mentioned structure.

The antifungal and antibacterial article of the present invention can be produced, for example, by coating the surface of a desired article with the dispersion of rare earth fertilized iron particles of the present invention, and then removing the solvent to form a coating film. Before applying the rare earth fertilizer iron dispersion, you can also apply an appropriate primer on the article.

The coating of the rare earth fertilizer granular iron dispersion liquid on the surface of the article can be carried out by a known method. For example, known coating devices such as bar coaters, doctor blades, spray coaters, roll coaters, slit coaters, gravure coaters, and dip coaters can be used. In addition, well-known coating tools such as sprays, rollers, brushes, and spatulas can be used.

The solvent after coating can be removed, for example, by heating at 10°C or above, 20°C or above, 30°C or above, 40°C or above, 50°C or above, 60°C or above, 70°C or above, 80°C or above, 90°C or above, Or above 100℃, and below 400℃, below 300℃, or below 200℃, let stand for more than 10 seconds, more than 1 minute, more than 30 minutes, more than 1 hour, more than 4 hours, more than 6 hours, more than 8 hours or more than 12 hours and less than 48 hours, or less than 24 hours. At this time, the coated article can also be placed under reduced pressure. [Example]

≪Synthesis of lanthanum fertilizer granular iron particles≫ (1) The synthesis of lanthanum fertilizer granular iron particles is in a ball mill using 10 mmΦ alumina balls as the grinding medium, and feeding 0.3 mole parts of La ₂ O ₃ and 0.4 mole parts of FeOOH. , and water, crush and mix for 5 hours. The obtained pulverized material was dried at 300° C. for 15 hours, and then disintegrated with a rotary pulverizer. The obtained crushed material was calcined at 1,000°C for 15 hours to synthesize lanthanum fertilized iron particles.

(2) Preparation of large-diameter lanthanum fertilizer iron particles By crushing the obtained lanthanum fertilizer granules with a hammer mill, large-diameter lanthanum fertilizer granular iron particles are obtained. The d50 particle size of the large-diameter lanthanum fertilizer iron particles obtained was 1.5 μm.

The obtained large particle size lanthanum fertilizer particles were qualitatively analyzed using a scanning fluorescence X-ray analyzer product name "ZSX Primus III+" manufactured by Rigaku Co., Ltd. As a result, it was found that the obtained lanthanum fertilized iron particles were lanthanum fertilized iron particles (formula La _1.4 Fe _0.6 O ₃ ) with La:Fe=70:30 (molar ratio).

In addition, a part of the large-diameter lanthanum fertilizer iron particles obtained was put into an aqueous solution of sodium hexametaphosphate with a concentration of 0.2% by weight, and ultrasonic waves with an output of 300 W were applied and dispersed for 3 minutes to obtain a dispersion. The particle size distribution of the obtained dispersion was measured using a particle size distribution measuring device manufactured by Microtrac BEL Co., Ltd., product name "MICROTRAC MT3000", at a refractive index of 2.40. The d50 particle size of the large-diameter lanthanum fertilizer iron particles is 1.5 μm.

(3) Preparation of small-diameter lanthanum fertilizer iron particles In a paint tank with a capacity of 0.3L, add 100 mL of water as a solvent, 10 g of the large-diameter lanthanum fertilizer iron particles obtained above (d50 particle size = 1.5 μm), and 100 g of Φ0.3 mm zirconia beads. Install the paint can into the paint shaking machine and disperse it for 24 hours at a vibration speed of 50 rpm.

By removing the beads with a filter, a dispersion containing small-diameter lanthanum fertilizer iron particles is obtained. The d50 particle size of the obtained small-diameter lanthanum fertilizer iron particles is 0.2 μm.

≪Preparation of agar medium≫ In 1,000 mL of pure water, 10 g of high-quality agar for culture media (product name "BA-70" manufactured by Ina Food Industry Co., Ltd.) and 30 g of fine sugar were added, and the mixture was heated and dissolved to obtain a solution. The resulting solution is poured into a sterilized petri dish and left to solidify at room temperature to prepare an agar medium.

≪Preparation of mold suspension≫ If commercially available wood is stored in a humid environment, mold will naturally proliferate and develop. 0.001g of the mold was taken, added to 10 mL of pure water, and stirred to mix, thereby preparing a mold suspension with a concentration of 0.01% by mass.

≪Example 1≫ (1) Preparation of lanthanum fertilizer granular iron dispersion Add 15 parts by mass of large-diameter lanthanum fertilizer iron particles and a dispersion of small-diameter lanthanum fertilizer iron particles (equivalent to 15 parts by mass of small-diameter lanthanum fertilizer iron particles) obtained above to the VONCOAT HY-364 resin. (Water-based acrylic urethane emulsion manufactured by DIC Co., Ltd., solid content 45% by mass) was mixed with 133.3 parts by mass (equivalent to 60 parts by mass of solid content) to prepare a lanthanum fertilizer granular iron dispersion.

A portion of the obtained lanthanum fertilizer particle iron dispersion was sampled, and the particle size distribution was measured. The measurement results are shown in Table 1 and Figure 1.

As can be seen in Figure 1, the lanthanum fertilizer granular iron particles contained in the lanthanum fertilizer granular iron dispersion of Example 1 contain 50% by volume of small particle size particles with a particle size of 0.1 to 1.0 μm in the cumulative volume distribution of the particle size distribution. 50% by volume of large particles with a particle size of more than 1.0 μm and less than 17.0 μm.

(2) Evaluation of mildew resistance Use a rod coater #10 to coat the obtained lanthanum fertilizer particle iron dispersion on the paper base material, let it stand at room temperature for 1 day (24 hours) and dry to form a coating film with a film thickness of 6 μm. Prepare samples for mildew resistance evaluation.

Cut the sample for fungal resistance evaluation obtained above into 5 cm square, and place it on the agar medium in a sterilized petri dish with the coated side facing up. On the coating surface of the sample, drop 200 μL of mold suspension, and rotate and spread evenly on and around the sample.

Cover the petri dish and let it stand at room temperature. Measure the area of mold produced after 45 days. Calculate the ratio of the area of mold produced to the sample surface (5cm×5cm=25cm ² ). The evaluation results are shown in Table 1.

(3) Evaluation of antibacterial properties (wiping method) Use a rod coater #10 to apply the obtained lanthanum fertilizer particle iron dispersion on the PET substrate, let it stand at room temperature for 1 day (24 hours), and dry to form a coating film with a film thickness of 6 μm, thereby producing Samples for antibacterial property evaluation.

A filter paper moistened with pure water was placed on a Petri dish, and a sample for antibacterial evaluation cut into a size of 10 cm × 5 cm was placed on the Petri dish with the coated side facing up. On the coated surface of the evaluation sample, 100 μL of milk was dropped and spread evenly on the coated surface. Cover the Petri dish, place it in a plastic bag with a zipper, and place it in a constant temperature and humidity chamber that has been adjusted to a temperature of 40°C and a relative humidity of 90% for 24 hours to deliberately allow bacteria to multiply.

After 24 hours, the evaluation sample was taken out, and the coated surface was wiped with the ATP wiping test reagent "LuciPac A3 Surface" manufactured by Kikkoman Biochemifa Co., Ltd., and the ATP amount and microorganism tester "Lumitester Smart" manufactured by the same company was used. , the amount of bacteria attached to the test reagent is measured in the form of the amount of ATP (adenosine triphosphate) luminescence, and the amount of bacteria _BAS on the coated surface of the evaluation sample is calculated.

In addition, a PET substrate not coated with the lanthanum fertilizer granular iron dispersion was used, and bacteria were intentionally propagated in the same manner as above, and the bacterial load _BAR on the PET substrate was calculated.

The antibacterial activity (ATP reduction rate) was calculated using the following formula using the bacterial load _BAS on the coated surface of the evaluation sample obtained above and the bacterial load _BAR on the PET substrate. The evaluation results are shown in Table 1. ATP reduction rate (%)={(BA _R -BA _S )/BA _R }×100

≪Comparative example 1≫ The antifungal properties were evaluated in the same manner as in Example 1 using a paper base material that was not coated with the lanthanum fertilizer granular iron dispersion liquid. The evaluation results are shown in Table 1.

≪Comparative Examples 2 and 3≫ Except for changing the composition of the components in the lanthanum fertilizer granular iron dispersion liquid as shown in Table 1, in the same manner as in Example 1, each lanthanum fertilizer granule iron dispersion liquid was prepared, and each evaluation was performed using these. The evaluation results are shown in Table 1.

As can be seen from Table 1, the sample of Comparative Example 2 prepared using a lanthanum fertilizer granular iron dispersion containing only large-diameter lanthanum fertilizer granular iron particles had excellent mildew resistance, but poor antibacterial properties. In addition, the sample of Comparative Example 3 prepared using a lanthanum fertilizer granular iron dispersion containing only small-particle-diameter lanthanum fertilizer granular iron particles had excellent antibacterial properties but poor mildew resistance.

Compared with these, it was confirmed that the sample of Example 1 prepared using a lanthanum fertilizer dispersion containing both small-diameter lanthanum iron particles and large-diameter lanthanum iron particles had mildew resistance and antibacterial properties. Both sexes are excellent.

[Fig. 1] Fig. 1 is a graph showing the particle size distribution of lanthanum fertilizer granular iron particles contained in the lanthanum fertilizer granular iron dispersion liquid obtained in Example 1.

Claims (12)

A rare earth fertilizer iron particle is represented by the following formula (1): In formula (1), Ln is a rare earth element selected from the group consisting of lanthanum, chromium, neodymium, and yttrium, and x is a number between 0.45 and less than 1.00; the aforementioned rare earth fertilizer iron particles have a particle size distribution The cumulative volume distribution contains small-sized particles and large-sized particles; the aforementioned small-sized particles are particles in the range of 0.01 to 1.0 μm; the aforementioned large-sized particles are particles with a diameter exceeding 1.0 μm and 17.0 μm Particles within the following range; and the ratio of the volume of the aforementioned small particle size particles to the total volume of the aforementioned small particle size particles and the aforementioned large particle size particles is not less than 10 volume % and not more than 90 volume %. The rare earth fertilizer iron particles of claim 1, wherein the ratio of the volume of the small particle size particles to the total volume of the small particle size particles and the large particle size particles is more than 50% by volume and less than 75% by volume. . The rare earth fertilized iron particles of Claim 1, wherein the ratio of the total volume of the small particle size particles and the large particle size particles to the total volume of the rare earth fertilized iron particles is 75% by volume or more. The rare earth fertilizer iron particles of claim 1, wherein the ratio of the volume of the small particle size particles to the total volume of the small particle size particles and the large particle size particles is more than 50% by volume and less than 75% by volume. ; Furthermore, the ratio of the total volume of the small particle size particles and the large particle size particles to the total volume of the rare earth fertilizer iron particles is 75% by volume or more. Such as the rare earth fertilizer iron particles of claim 1, wherein the d50 particle size of the aforementioned small particle size particles is 0.05~0.50 μm; The d50 particle size of the aforementioned large particle size particles is 1.1 to 5.0 μm or less. Such as the rare earth fertilizer iron particles of claim 1, wherein the aforementioned small particle size particles are particles with a particle size in the range of 0.10~0.50 μm; And the aforementioned large particle size particles are particles with a particle size in the range of 1.0 to 5.0 μm or less. For example, the rare earth fertilizer iron particles according to any one of claims 1 to 6, wherein x in the aforementioned formula (1) is a number ranging from 0.65 to 0.85. Such as the rare earth fertilizer iron particles according to any one of claims 1 to 6, wherein Ln in the aforementioned formula (1) is lanthanum. A rare earth fertilizer iron dispersion liquid contains the rare earth fertilizer iron particles according to any one of claims 1 to 6, a resin, and a solvent. A mildew-proof and antibacterial article having a coating film containing rare earth fertilizer iron particles according to any one of claims 1 to 6. For example, the anti-mold and antibacterial articles in claim 10 include utensils, curtains, door handles, partitions, films for preventing droplets, protective films for smartphones, protective films for touch panels, masks, and hanging rings for trains, Packaging materials, general printed matter, business forms, banknotes, securities, cards, home appliances, air conditioner-related components, toys, building interiors, building exteriors, automobile interiors, train interiors, or aircraft interiors. For example, the anti-mold and anti-bacterial articles in claim 11 are transparent partitions, transparent droplet prevention films, protective films for smartphones, or protective films for touch panels.

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