JP2016019548A - Metal coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal coating material capable of suppressing heat evolution following oxidation when coating a seed, as much as possible, excellent in workability during heat release, and excellent in adhesive strength to the seed.SOLUTION: A metal coating material 10 is mainly made of iron, and attaches metal powder bodies 11 including at least, granular fine particles 11A and tubular fine particles 11B to a seed 20 for coating the seed 20, in which, a ratio of particles having 63-150 μm in particle size distribution of the metal powder bodies 11 measured by using a JIS test sieve, is equal to or more than 23 mass%.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a metal coating material for coating a rice seed by attaching a metal powder containing iron as a main component and containing at least granular fine particles and plate-like fine particles to rice seeds.

  Since direct seeding cultivation of rice can eliminate the seedling and rice planting operations, it is expected that the labor can be greatly reduced, the use materials can be reduced, and the cost of rice cultivation can be reduced.

  In the direct sowing cultivation, it is known to coat rice seeds with iron. Iron-coated seeds have a high specific gravity, so that the state of seeding by spot sowing is less likely to be disturbed by rainwater or incoming water, and a hard shell of iron coating is formed, which is highly resistant to bird damage. Moreover, since seeding is carried out on the soil surface, seed emergence is improved. Since the iron-coated seeds can be stored for a long period of time, the operation of coating rice seeds with iron can be carried out during the agricultural off-season or the like, and the period until sowing can be stored in an iron-coated state.

  Iron-coated seeds must satisfy the following conditions. That is, the seeds sowed will come into contact with water and should not collapse in an environment where the iron coating is in contact with water. Since rice seeds are sown using a machine such as a sowing machine, they must have strength characteristics that do not collapse due to mechanical impact. After sowing, rice seeds that have become sprouting due to the influence of the accumulated temperature and moisture infiltrated from the iron coating must break the iron coating, and then the iron coating must be peeled off by the action of water in the soil. Furthermore, in order to prevent damage to rice seeds during the coating process, it is desirable that the coating be performed easily under mild conditions and in a short time, and the pH of the coating material is also required to be close to neutral.

Iron-coated seeds are usually coated with iron powder and calcined gypsum and sprayed with water.
For example, in Patent Document 1, to rice seed, iron powder, and 0.5-2% sulfate / chloride or 0.5-35% calcium sulfate / hydrate thereof in a mass ratio to the iron powder, Of iron powder-coated rice seeds that are granulated by adding water, and after supplying and solidifying the iron powder by rust generated by oxidation reaction of metallic iron powder by supplying water and oxygen, and then drying The manufacturing method is described.

  As the iron powder, reduced iron powder, atomized iron powder, iron powder produced as industrial waste from shot blasting process, etc. are disclosed, and it is described that iron powder with particularly small particle size tends to adhere to rice seeds. It is. In this method, sulfate / chloride is used as an oxidation accelerator in order to accelerate the oxidation reaction of iron powder.

  The oxidation reaction of iron powder proceeds if there is water and oxygen. In the method described in Patent Document 1, iron powder and sulfate / chloride are mixed with wet rice seeds, and water is sprayed to efficiently oxidize iron powder. When water disappears due to drying or the like, the oxidation reaction is completed.

  The coating layer produced using the oxidation reaction of iron powder adheres to the rusted iron powder on the surface of rice seeds, and this adhesive action improves the coating strength, making it difficult to peel off from rice seeds as large pieces. It is supposed to be.

Japanese Patent No. 44441645

  In general, when rice seeds are exposed to a temperature of about 50 to 60 ° C. for about 10 minutes under high humidity conditions, they may be damaged by heat, and lack the stability of germination in direct sowing cultivation.

  Rice seeds coated with iron powder generate heat during the oxidation reaction, so it is necessary to avoid thermal damage to the rice seeds. If moisture remains in the iron-coated seeds, the heat generated by the oxidation reaction continues. If the iron powder oxidation reaction is not completely completed during the coating operation, for example, if the iron-coated seeds are left in bulk in a container such as a bag or a bucket, the heat generated by the oxidation reaction May accumulate and cause heat damage to rice seeds.

  Therefore, in the method described in Patent Document 1, in order to avoid thermal damage of the seed coated with iron powder, after taking out from the granulator, each iron coated seed can be radiated efficiently, for example, without making a lump. It was necessary to dissipate heat by spreading it thinly in a box with a wide bottom. As described above, the method disclosed in Patent Document 1 requires a troublesome work for avoiding thermal damage to rice seeds, which is troublesome.

  Accordingly, an object of the present invention is to provide a metal coating material that can suppress heat generation due to oxidation during coating of seeds as much as possible, is excellent in workability during heat dissipation, and has excellent adhesion strength to seeds. .

  The metal coating material according to the present invention for achieving the above object is a metal coating material for coating a seed by attaching a metal powder containing iron as a main component and containing at least granular fine particles and plate-like fine particles to the seed. And the 1st characteristic structure exists in the point which made the ratio of the particle | grains of 63-150 micrometers in the particle size distribution of the said metal powder measured using the sieve for JIS testing 23weight% or more.

  “Mainly comprising iron” means that the metal coating material contains 50% or more of metallic iron. Since the metal coating material contains iron as a main component, when the metal coating material is attached to the seed, the oxidation reaction of the iron proceeds due to moisture contained in the seed or moisture provided from the outside. Rust is generated by the oxidation reaction, and the iron powder is adhered and solidified to the rice seeds by the rust, and the seeds can be coated with the metal coating material.

  Since the plate-like fine particles have a flaky or flat shape, the flat surface side of the plate-like fine particles easily adheres along the seed surface. Further, since the flat surface of the plate-like fine particles easily comes into contact with other fine particles, for example, the other fine particles are easily connected in the lateral direction and the vertical direction of the plate-like fine particles, so that the plate-like fine particles are in contact with other fine particles. It becomes easier to reliably coat the seed over the whole seed.

  In this way, the metal coating material contains granular fine particles and plate-like fine particles, and particularly when there are edge portions and uneven portions on the surface of the seed, the plate-like fine particles connect other fine particles in a bridge shape. The seeds can be reliably coated even on edge portions and uneven portions that are difficult to coat.

  The metal powder of the metal coating material of the present invention has a particle size distribution such that the proportion of particles of 63 to 150 μm is 23% by weight or more. The degree of temperature rise of the metal coating material of the present invention exhibiting such a particle size distribution is higher than the degree of temperature rise of conventional iron powder (reduced iron powder / atomized iron powder) as shown in Example 2 described later. Perceived to be suppressed. Moreover, as shown in Example 3 to be described later, the temperature rise of the coated seed coated with the metal coating material on the seed is also suppressed from the temperature rise of the coated seed coated with the conventional iron powder. It is recognized. That is, if the metal coating material of the present invention is used, the degree of temperature rise when the seed is coated is suppressed, so that it is easy to prevent a thermal failure that occurs when the seed is coated.

  By suppressing the degree of temperature rise during the oxidation reaction of the metal coating material of the present invention, the work (heat radiation work) when the coated seed is radiated after coating the seed becomes easy. For example, in the case of conventional iron powder having a high temperature rise during oxidation, it is necessary to dissipate heat as quickly as possible so as not to increase the deposition thickness of the coating seeds during heat radiation work. However, if the coated seed is coated with the metal coating material of the present invention, the degree of temperature rise can be suppressed. Therefore, even if there is a certain amount of deposition thickness, it is difficult to raise the temperature to a temperature at which the seed will be damaged by heat. Therefore, it is not necessary to widen the coating seeds so that the thickness of the coating seeds deposited does not increase during the heat radiation operation, so that the workability during heat radiation is excellent. In addition, the space required for the heat radiation work can be reduced.

  Therefore, as in the present invention, if the particulate fine particles and the plate-like fine particles are provided, the rapid temperature rise can be suppressed, which is excellent in safety, and further, compared with the case where the metal powder is composed only of the plate-like fine particles. Metal coating material with excellent cost performance.

  Moreover, as shown in Example 4 described later, it is recognized that the coating strength of the metal coating material of the present invention is equivalent to that of conventional iron powder. Therefore, if it is the metal coating material of this invention, it will become the thing which was excellent in the adhesion strength with respect to a seed like the conventional iron powder.

  The second characteristic configuration of the metal coating material according to the present invention is that the mixing ratio of the granular fine particles and the plate-like fine particles is 8: 2 to 2: 8.

  As shown in Example 2 described later, when the mixing ratio of the granular fine particles and the plate-like fine particles is 8: 2 to 2: 8, it is recognized that the degree of temperature rise is suppressed as compared with the conventional iron powder. It is done. Therefore, for example, the metal coating material of the present invention can be easily produced by mixing the particulate fine particles and the plate-like fine particles that are separately produced so that the ratio is 8: 2 to 2: 8.

  The third characteristic configuration of the metal coating material according to the present invention is that the mixing ratio of the granular fine particles and the plate-like fine particles is 8: 2 to 7: 3.

  As shown in Example 4 described later, the coating strength of the metal coating material of the present invention is the same as that of conventional iron powder when the mixing ratio of granular fine particles and plate-like fine particles is 8: 2 to 7: 3. It is recognized that Therefore, the metal coating material of this configuration has particularly excellent adhesion strength to seeds.

  The 4th characteristic structure of the metal coating material which concerns on this invention exists in the point which made content of metal iron 50 weight% or more.

When the seed is covered with a metal coating material, iron powder is attached to the seed by rust generated by oxidation of iron.
As in this configuration, the metal coating material contains 50% by weight or more of metal iron, so that the oxidation reaction of the metal iron can proceed reliably in the presence of water to adhere the metal coating material to the whole seed. Sufficient rust can be generated.

  The fifth characteristic configuration of the metal coating material according to the present invention is that the thickness of the plate-like fine particles is 30 μm or less, and the ratio between the major axis and the thickness is 1.5-20.

  If the thickness of the plate-like fine particles is 30 μm or less and the aspect ratio is 1.5 or more, it can be clearly identified as fine particles exhibiting a plate-like shape. The greater the aspect ratio, the greater the degree of plate shape (flatness). If the aspect ratio is up to about 20, it becomes easy to handle plate-like fine particles having excellent impact resistance.

  A sixth characteristic configuration of the metal coating material according to the present invention is that the seed is rice seed.

  Rice seeds coated with the metal coating material of the present invention can be used for direct sowing cultivation. Since the direct sowing cultivation is a cultivation method that saves seedling and rice planting work, it is possible to reduce labor, reduce use materials, and reduce costs by coating the rice seed with the metal coating material.

It is the schematic of the coating seed coated with the metal coating material of this invention, and the microscope picture figure of a metal coating material. It is a graph which shows distribution of the aspect ratio of a plate-shaped fine particle. It is the graph which showed the result of having measured the temperature at the time of the oxidation reaction of the metal coating material of this invention. It is the graph which showed the result of having measured the temperature at the time of the oxidation reaction of the metal coating material of this invention. It is the graph which showed the result of having measured the temperature at the time of the oxidation reaction of the coating seed coated with the metal coating material of this invention. It is the graph which showed the result of having measured the temperature at the time of the oxidation reaction of the coating seed coated with the metal coating material of this invention in the seedling box. It is the graph which showed the result of the disintegration test.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the metal coating material 10 of the present invention is made of iron as a main component, and a metal powder 11 containing at least granular fine particles 11 </ b> A and plate-like fine particles 11 </ b> B is attached to the seeds 20. It is to be coated. Particularly, in the metal coating material 10 of the present invention, the proportion of particles of 63 to 150 μm in the particle size distribution of the metal powder 11 measured using a JIS test sieve is 23% by weight or more.

  As the seed 20, plant seeds such as rice seeds and wheat seeds are used. As the rice seed varieties, japonica and indica can be used. The coated seed X in which the metal coating is applied to the seed 20 has a high specific gravity and sinks in the water, so that it is difficult to flow by water after sowing. Have. When it is desired to impart such characteristics to a desired seed, the metal coating material of the present invention can be applied to any seed. Hereinafter, this embodiment demonstrates the case where a rice seed is used.

  The seed 20 coated with the metal coating material 10 can be used for direct sowing cultivation. The time for coating the metal coating material 10 on the seed 20 is not particularly limited as long as it is before sowing such as direct sowing, such as the agricultural free season.

  The metal coating material 10 is configured to contain iron as a main component. In this specification, “mainly composed of iron” means that the metal coating material 10 contains 50% or more, preferably 70% by weight or more of metallic iron. As described above, when the metal coating material 10 contains iron as a main component, the iron oxidation reaction can be reliably advanced in the presence of water.

  Iron is preferably in the form of iron powder. The iron powder only needs to contain powdered iron (Fe), for example, metallic iron (pure iron powder), reduced iron powder, atomized iron powder, electrolytic iron powder, and industrial waste. The iron powder produced can be used. Moreover, as long as the metal coating material 10 contains iron as a main component, an alloy, other metal particles, and metal oxide particles may be contained. For example, when atomized iron powder is used as alloy steel powder, it is possible to use complete alloy powder or partial alloy powder. The metal coating material 10 may contain, for example, oxygen, carbon, sulfur, silicon dioxide and the like in addition to the metal.

  The metal coating material 10 contains at least granular fine particles 11 </ b> A and plate-like fine particles 11 </ b> B as the metal powder 11. The metal coating material 10 may include, for example, rod-shaped fine particles as other fine particles 12 having a shape other than a granular or plate shape.

  The “particulate particulate 11A” refers to a particulate having a spherical appearance and an irregular granular shape similar to the spherical appearance.

  On the other hand, the “plate-like fine particles 11B” are fine particles having an irregular shape and a flat shape. The flat surface side of the plate-like fine particles 11B easily adheres along the seed surface. In addition, other fine particles easily come into contact with the flat surface of the plate-like fine particles 11B. Therefore, for example, other fine particles are connected in the horizontal direction and the vertical direction of the plate-like fine particles 11B, and the plate-like fine particles 11B serve as a bridge with other fine particles.

  As described above, the metal coating material 10 contains the particulate fine particles 11A and the plate-like fine particles 11B, so that the plate-like fine particles 11B are in a bridge shape with respect to the edge portions and the uneven portions present on the surface of the seed 20 in particular. Of fine particles.

  In this specification, an aspect ratio (particle diameter / particle thickness) calculated from the ratio of the particle diameter (major axis) and the particle thickness is used as an index representing the degree of plate shape (flatness) of the fine particles. The plate-like fine particles 11B used in the metal coating material 10 of the present invention have, for example, a thickness of 30 μm or less, preferably 20 μm or less, and an aspect ratio calculated from the major axis and thickness of 1.5 or more. do it. If the thickness of the plate-like fine particle 11B is 30 μm or less, preferably 20 μm or less and the aspect ratio is 1.5 or more, it can be clearly identified as a fine particle having a plate-like shape. When the aspect ratio is up to about 20, preferably up to 10, the plate-like fine particles 11B having excellent impact resistance are obtained.

  As for the aspect ratio, for example, a photograph of the shape of the manufactured plate-like fine particle 11B sample was taken with a scanning electron microscope, and particles with different thickness levels (thick, middle, thin) were randomly extracted and photographed. From the photograph, the particle diameter (major diameter) and the particle thickness are measured and calculated.

The metal powder 11 can be manufactured as a raw material from mill scale, which is a layer of iron oxide formed on the surface of the steel material in the process of manufacturing the steel material, or iron ore. Reduced iron (sintered into a lump) obtained by reducing such raw materials with coke is crushed and pulverized by various pulverizers such as impact type, grinding type and shear type, The particulate fine particles 11A are obtained by classification.
Using the particulate fine particles 11A as a raw material, for example, a plate is formed by a vibration mill. The vibration mill is loaded with media together with the particulate fine particles 11A to give vibration. As the medium, it is preferable to use a metal medium having excellent wear resistance such as a steel ball, but is not limited thereto. The particulate fine particles 11A can be formed into a plate shape by applying an impact force to the particulate fine particles 11A by the media and the wall surface of the mill container.
The plate-like conditions may be, for example, an occupation ratio of 40 to 95%, an amplitude of 3 to 10 mm, a frequency of 10 to 30 Hz, and a residence time of 75 to 150 minutes. After the treatment with the vibration mill, the fine particles 11B are obtained by classification by a method such as vibration sieve and air flow dispersion.

  In this way, the plate-like fine particles 11B are produced from the granular fine particles 11A. The manufacturing cost of the metal coating material 10 can be suppressed, so that the ratio of the plate-shaped fine particle 11B contained in the metal coating material 10 of this invention is small.

  The metal powder 11 used in the metal coating material 10 of the present invention has a particle size distribution such that the proportion of particles of 63 to 150 μm is 23% by weight or more. The particle size distribution is measured using a JIS test sieve (JIS Z8801-1). The metal powder 11 has a ratio of 75 to 150 μm particles of 9.5% by weight or more.

  If the mixing ratio of the granular fine particles 11A and the plate-like fine particles 11B is 8: 2 to 2: 8, and preferably the mixing ratio of the granular fine particles 11A and the plate-like fine particles 11B is 8: 2 to 7: 3, the seed 20 is coated. The degree of temperature rise is suppressed, and the adhesion strength to the seed is excellent.

The metal coating material 10 of the present invention is coated on seeds as follows, for example.
The seed is preferably pretreated by immersing it in water before coating. About 0.5 times as much metal coating material 10 as the weight of the seed and about 5 to 10% calcined gypsum (oxidation accelerator: calcium sulfate CaSO4) of the metal coating material 10 are mixed with this seed.
The ratio of the metal coating material 10 and calcined gypsum is not restricted to this, It is good to change suitably. Further, potassium sulfate, magnesium sulfate, potassium chloride, calcium chloride, magnesium chloride and the like may be used instead of calcined gypsum used as an oxidation accelerator.

These are mixed with stirring in a granulator, and water is sprayed as appropriate to promote the oxidation reaction. If necessary, a finished calcined gypsum may be added about 5% of the metal coating material 10.
When the metal coating material 10 contains iron, when water is supplied by spraying or the like when the metal coating material 10 is brought into contact with the seed 20, the oxidation reaction of the iron proceeds. The iron powder is adhered and solidified to the seed 20 by the rust generated by the oxidation reaction to form the coating layer 13, and the seed 20 can be coated with the metal coating material 10.

  The granulated coated seed X is taken out, and an oxidation reaction is allowed to proceed at room temperature, for example, so as not to hinder heat dissipation of the coated seed. The coated seed X coated with the metal coating material 10 of the present invention is suppressed in temperature rise so that it is difficult to raise the temperature to a temperature at which the seed 20 is damaged even if there is a certain accumulation thickness. Therefore, it is not necessary to spread the coating seed X so that the deposition thickness of the coating seed X during the heat radiation operation does not increase.

The deposition thickness of the coating seed X can be appropriately selected depending on the amount of the coating seed X, the season, and the outside air temperature. Since the metal coating material 10 of the present invention can suppress the degree of temperature rise during the oxidation reaction, it may have a certain thickness (for example, about 2 cm).
When the moisture of the coated seed X is lost, the oxidation reaction is completed, and the coated seed X coated with the metal coating material 10 of the present invention can be manufactured.

  Below, the Example of the metal coating material 10 of this invention is described.

[Example 1]
A metal coating material 10 of the present invention was produced.
First, granular fine particles 11A were produced using iron ore as a raw material. An appropriate amount of reduced iron ingot obtained by reducing mill scale or iron ore was put into a hammer mill which is an impact-type and shear-type pulverizer, and pulverized under predetermined conditions. Granular fine particles 11A were obtained by classification using a vibrating sieve (a sieve mesh opening of 109 μm).

  The granular fine particles 11A are put into a continuous vibration ball mill (CH-35: manufactured by Chuo Kako Co., Ltd.) together with steel balls (1/2 inch), and the occupation ratio is 70%, the amplitude is 6 mm, the vibration frequency is 20 Hz, and the residence time is 120 minutes. The plate-like treatment was performed under the conditions described above. Classification was performed using a vibration sieve (a sieve mesh opening of 109 μm) to obtain plate-like fine particles 11B.

A plurality of types of metal coating materials 10 were prepared by variously changing the mixing ratio (granular fine particles: plate-like fine particles) of the granular fine particles 11A and the plate-like fine particles 11B thus obtained. Invention Example 1 (90:10), Invention Example 2 (85:15), Invention Example 3 (80:20), Invention Example 4 (75:25), Invention Example 5 (70: 30), Invention Example 6 (65:35), Invention Example 7 (60:40), Invention Example 8 (50:50), Invention Example 9 (40:60), Invention Example 10 (20: 80)). For Invention Example 3 (80:20), five types of samples were prepared (Invention Examples 3-1 to 3-5).
Table 1 also shows the particle size distribution of only the granular fine particles 11A (Comparative Example 1), only the plate-like fine particles 11B (Comparative Example 2), and Comparative Example 3 (current standard iron powder DSP317, manufactured by DOWA IP Creation Co., Ltd.). It was. In the particle size distribution shown in Table 1, particles having excessively large particle sizes are excluded. FIG. 1 shows electron micrographs of Invention Example 3 (FIG. 1B) and Invention Example 8 (FIG. 1C).

From Table 1, the particle size distribution of Examples 1 to 10 of the present invention is
Less than 45 μm: 36.8-46.7% by weight,
45 to less than 63 μm: 30.0 to 33.1% by weight,
63 to less than 75 μm: 12.7 to 18.5% by weight,
75 to less than 106 μm: 9.2 to 12.7% by weight,
106 to less than 150 μm: 0.2 to 0.7% by weight, and particles of 150 μm or more were not contained.

  Table 2 shows the proportions of particles having a particle size distribution of 63 to 150 μm and 75 to 150 μm with respect to Inventive Examples 1 to 10 and Comparative Examples 1 to 3.

  From Table 2, the ratio of the particle | grains of less than 63-150 micrometers in the particle size distribution of the metal powder 11 contained in the metal coating material 10 of this invention is 23.3-31.7 (about 23-32) weight%, and is 150 micrometers. Considering that the above particles are not contained, this is a ratio of particles of 63 μm or more. In addition, the ratio of particles having a particle size distribution of 75 to less than 150 μm (ratio of particles having a diameter of 75 μm or more) in the particle size distribution of the metal powder 11 was 9.5 to 13.2% by weight.

  In the metal coating material 10 of the present invention, the aspect ratio (particle diameter / particle thickness) of the plate-like fine particles 11B was determined and shown in Table 3. The calculated distribution of aspect ratio is shown in FIG.

  The selected 31 particles had a particle diameter of 15 to 115 μm, a particle thickness of 2 to 20 μm, and a calculated aspect ratio in the range of 1.5 to 38.3.

  Table 4 shows the compositions (% by weight) of the three types of metal coating materials 10 among the inventive examples.

[Example 2]
To what extent the metal coating material 10 of the present invention generates heat by an oxidation reaction was examined.
3% of each sample in 20 g of Invention Example 3-1 (80:20), Invention Example 7 (60:40), Invention Example 9 (40:60), Invention Example 10 (20:80) 2 mL of saline was added, and after 30 seconds of stirring, the sample was transferred to a 30 mL paper cup, and the temperature of the sample was measured with a thermocouple (room temperature, described up to 23 minutes). For Comparative Examples 1 to 3, the temperature was measured under the same conditions. The results are shown in FIG.

  As a result, the temperature of the metal coating material 10 of the present invention (example of the present invention) reached about 29 to 32 ° C. in about 10 minutes after the start of measurement, and thereafter it was recognized that the temperature was maintained around this temperature. On the other hand, in Comparative Example 3 (DSP 317), it was recognized that the temperature was continuously increased after 10 minutes from the start of measurement and the temperature was also increased after 23 minutes.

Temperature measurement was performed over 3 hours under the same conditions. Samples used were Invention Example 3-1, Invention Example 8, Comparative Examples 1 to 3, Comparative Example 4 (reduced iron powder for metallurgy DNC, manufactured by DOWA IP Creation Co., Ltd.), and Comparative Example 5 (atomized iron for metallurgy). Powder Atmel 270M series, manufactured by Kobe Steel, Ltd.) and Comparative Example 6 (reduced iron powder for metallurgy, JFE Steel Corporation). The results are shown in FIG.
For Comparative Examples 4 to 6, Table 5 shows the particle size distribution.

From Table 5, the particle size distribution of Comparative Examples 4 to 6 is
Less than 45 μm: 18.8-31.9% by weight,
45 to less than 63 μm: 13.5 to 16.7% by weight,
63 to less than 75 μm: 10.1 to 15.8% by weight,
75 to less than 106 μm: 19.2 to 34.1% by weight,
106 to less than 150 μm: 11.7 to 22.7% by weight,
150 μm or more: 0.8 to 11.5% by weight.

  Table 6 shows the ratio of particles of 63 μm or more and the ratio of particles of 75 μm or more in the particle size distributions of Comparative Examples 4 to 6.

  From Table 6, in the particle size distribution of Comparative Examples 4 to 6, the ratio of the particles of 63 μm or more was 53.6 to 67.7% by weight, and the ratio of the particles of 75 μm or more was 42.4 to 57.6% by weight. . That is, in the samples of Comparative Examples 4 to 6, the ratio of the particles of 63 μm or more (23.3 to 31.7% by weight) in the inventive examples 1 to 10 and the ratio of the particles of 75 μm or more (about 9.5 to 9.5). 13.2% by weight).

  As a result of the temperature measurement, Comparative Examples 3, 4, 5, and 6 reached 50 ° C. or higher by 100 minutes. On the other hand, Example 3-1 of the present invention, Example 8 of the present invention, and Comparative Examples 1 and 2 did not reach 40 ° C.

From this result, when the iron powders of Comparative Examples 3, 4, 5, and 6 are coated on the seed, the temperature is raised to a temperature at which there is a risk of causing heat damage to the rice seed due to heat generated during the oxidation reaction. Therefore, when rice seeds are coated with the iron powders of Comparative Examples 3, 4, 5, and 6, it is necessary to be careful not to deposit the coated seeds thickly during heat dissipation in order to avoid thermal damage to the rice seeds.
On the other hand, when the seeds were coated with the metal coating material 10 of Invention Example 3-1 and Invention Example 8 on the seeds, it was considered that there was almost no possibility of causing thermal damage to the seeds due to heat generation during the oxidation reaction.

Example 3
Rice seeds (Koshihikari: Japonica seeds) were coated with the metal coating material 10 of the present invention by the following method.
Rice seeds immersed in water; 2 kg, metal coating material 10 of Invention Example 3-1 (80:20); 1 kg, calcined gypsum; 0.1 kg is put into a coating machine (KC-151: Keibunsha Seisakusho Co., Ltd.) These were mixed while spraying an appropriate amount of water. After mixing for 13 minutes at room temperature, 0.05 kg of finished calcined gypsum was added, and these were mixed for 2 minutes while spraying an appropriate amount of water. A total of 0.4 kg of water was used.
The granulated coated seed X was taken out from the coating machine, spread so as to have a thickness of about 2 cm, and the oxidation reaction proceeded at room temperature. The coated seed X was allowed to stand until it reached room temperature, and then the coated seed X produced in a predetermined container was stored.

  In Comparative Example 3 (DSP317), rice seeds were coated in the same manner (conventional coated seeds).

  For the coated seed X coated with Example 3-1 (80:20) of the present invention and the conventional coated seed coated with Comparative Example 3 (DSP 317), the temperature of heat generated by the oxidation reaction was measured (FIGS. 5 and 6). . The measurement was started when it was removed from the coating machine.

  FIG. 5 shows the results of measuring the temperature of the coated seed X of the present invention and the conventional coated seed by depositing the coated seed in a plastic container (height 13 × 6.75 × 13 cm: 1140 mL) to a thickness of 50 mm. (Room temperature). FIG. 6 shows the results of measuring the temperature of the coated seed X of the present invention deposited on a seedling box (height 28 × 58 × 3 cm: 4827 mL) at a thickness of 30 mm (outside temperature 6 to 7 ° C.). ).

  From FIG. 5, a temperature peak (about 92 ° C.) was observed at about 6 hours (about 350 minutes) in the conventional coated seed. On the other hand, in the coated seed X of the present invention, no high temperature peak as observed in the conventional coated seed was observed by 6 hours, and the temperature could be suppressed to about 37 ° C. In the conventional coated seed, the time required to raise the temperature to 37 ° C. was about 4 hours. That is, the time required to reach the predetermined temperature in the coated seed X of the present invention was 1.5 times that of the conventional coated seed.

  From FIG. 6, when heat was dissipated in the seedling box, a difference was observed in the degree of temperature rise by about 400 minutes in the coated seed X of the present invention and the conventional coated seed (the coated seed X of the present invention: about 14 ° C., Conventional coated seeds: 17.8 ° C).

  From the results of FIGS. 5 and 6, it was recognized that the temperature of the coated seed X coated with the metal coating material 10 of the present invention was suppressed more than the conventional coated seed coated with iron powder.

In the conventional coated seeds, the high temperature peak observed in FIG. 5 was not observed, but since the tendency of the temperature to rise can be read from the graph of FIG. 6, a temperature peak is expected to appear after 400 minutes. It was. The coated seed X of the present invention is also considered to gradually increase in temperature in a state in which the degree of temperature rise is suppressed compared to the conventional coated seed, but does not increase to a high temperature as observed in the conventional coated seed. Therefore, there is no risk of causing heat damage to rice seeds.
Thus, since the time when the temperature peak appears varies depending on the seed deposition thickness and the outside air temperature, the time for releasing heat after coating may be appropriately determined according to the amount of seed to be processed and the season.

Example 4
In the coating seed X produced in Example 3, the coating strength of the metal coating material 10 of the present invention (Invention Examples 1 to 6) was evaluated (disintegration test).
The coated seed X, whose weight was measured, was placed on a test sieve (diameter 200 mm, sieve mesh opening 1 mm). In this state, the coated seed X cannot pass through the mesh of the test sieve.
The test sieve on which the coated seed X was placed was vibrated for 10 minutes with a known low-tap shaker which is a particle size distribution measuring device. The weight of the coated seed X after vibration was measured, the weight of the coated seed X before and after vibration was compared, and the residual ratio (%) of the metal coating material 10 on the surface of the rice seed was calculated (Table 7, FIG. 7). The conventional coated seeds coated in Comparative Examples 1 and 3 were similarly subjected to a disintegration test, and the results were shown.

  As a result, the residual ratio of the metal coating material 10 of Invention Examples 3 to 5 (mixing ratio of granular fine particles and plate-like fine particles of 8: 2 to 7: 3) is 98.8% or more, and Comparative Example 3 (DSP317) The residual ratio was almost the same as). In particular, Example 4 of the present invention had the same residual rate as Comparative Example 3 (DSP 317), and was the most excellent in strength among the examples of the metal coating material 10 of the present invention. Thus, it was found that the metal coating material 10 of the present invention has practical strength even when the seed 20 is coated.

  The metal coating material of the present invention can be used for seed coating.

DESCRIPTION OF SYMBOLS 10 Metal coating material 11 Metal powder 11A Granular microparticle 11B Plate-shaped microparticle 12 Other microparticle 20 Seed

The metal coating material according to the present invention for achieving the above object contains iron as a main component and contains at least granular fine particles and plate-like fine particles .

Claims (1)

A metal coating material that has iron as a main component and coats the seed by attaching a metal powder containing at least granular fine particles and plate-like fine particles to the seed,
The metal coating material whose ratio of the particle | grains of 63-150 micrometers in the particle size distribution of the said metal powder measured using the sieve for JIS tests is 23 weight% or more.