JPH0244793B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a coated fertilizer with a color display that allows easy visual confirmation of the end of the fertilizer's effectiveness.

Conventional technologies and their problems Conventional chemical fertilizers or advanced chemical fertilizers that combine nitrogen, phosphorus, and potassium components, or single-component fertilizers are inefficient in their normal forms because of large runoff losses due to rainwater and irrigation water after fertilization. It also has drawbacks such as a short validity period.

Therefore, with the aim of eliminating these drawbacks and further saving labor, various slow-release fertilizers designed to gradually dissolve fertilizing ingredients in accordance with plant growth have been proposed and put into practical use. .

One type of slow-release fertilizer is a so-called coated fertilizer, which is a molded fertilizer coated with a thermosetting resin, olefin polymer, vinylidene chloride polymer, petroleum resin, wax, or the like.

This coated type of slow-release molded fertilizer has a mechanism in which water enters through pinholes (porous parts) in the relatively hard film and the fertilizer components gradually dissolve, causing the fertilizer effectiveness to decrease or The weak point was that the fertilizer's lifespan could not be determined from its appearance because the shape of the fertilizer remained unchanged even after the fertilizer was finished.

Accordingly, an object of the present invention is to provide a coated fertilizer whose useful life can be visually and easily determined.

Means for Solving the Problems As a result of various studies, the inventor of the present invention colored the outer periphery of a molded solid fertilizer with dye and/or pigment, and further coated it with resin etc. to create a porous film. The present invention was completed by successfully visually determining the end of the fertilizer effect by designing the coloring component to elute from the fertilizer component in conjunction with the fertilizer component.

That is, the present invention is a coated fertilizer with a color display, which is made by applying a resin coating to a molded fertilizer having a colored layer on the surface formed by applying a water-soluble dye or pigment, and which allows visually determining the fertilization life.

Structure of the Invention The fertilizing ingredients of the coated fertilizer with color display in the present invention are not particularly limited as long as they are solid at room temperature, and examples thereof include ammonium sulfate, urea, ammonium phosphate, potassium sulfate, potassium chloride, etc.
Depending on the purpose of use, these fertilizers may be used alone or in mixtures, but particularly preferred target fertilizers are low- or medium-intensity fertilizers for agriculture, horticulture, or home gardens that contain nitrogen, phosphorus, potassium, etc. in appropriate proportions. degree or advanced chemical fertilizer.

Solid fertilizers are formed using a formulation machine commonly used in fields such as agrochemicals and pharmaceuticals, but in addition to the fertilizer ingredients, internal additives such as wax and polyolefin, or heated tumbling granules are added to adjust the slow-release properties. In this case, it is possible to use various components conventionally known in this field, such as granulating agents such as wax and polyolefin, as well as external additives such as talc.

If the dyes and pigments used to form a colored layer by applying them to the outer periphery of the formed solid fertilizer are soluble in the coating resin component applied to the surface, they will not be eluted by water such as irrigation water. The color simply fades due to deterioration in weather resistance, and it is not possible to clearly determine from the appearance whether the fertilizer effect has diminished or ended. Therefore, the dyes and pigments used for coloring must be insoluble in the coating resin component and have the property of eluting in conjunction with the fertilizing components eluted by water that enters from the porous portion of the coating resin. A wide range of water-soluble dyes, such as those commercially available as watercolors, and pigments that exude with water can be used.

Since such dyes and pigments are available in a large number of various colors, it is extremely convenient because the color tones can be used appropriately depending on the type of fertilizer component, target plant, period of end of fertilizer effect, etc.

The amount of dye and/or pigment applied to form the colored layer is such that the fading of the color of the molded fertilizer can be clearly seen, and although it varies depending on the type of dye and pigment, it is generally 2 to 50 g per 1000 g of the molded fertilizer.

Any method that can be used to uniformly color the outer peripheral surface of the molded fertilizer can be applied, such as dipping in a dye solution or using a coater that supplies the dye solution while rolling the molded fertilizer. .

The coating resin applied to the surface of the colored molded fertilizer can be any resin or resin used in conventional coated fertilizers, as long as it is transparent enough to see through the color of the molded fertilizer and does not dissolve the coloring components. A composition with other components can be used, and a film can be formed by employing a known coating method corresponding to each resin.

Typical resins include thermosetting resins such as epoxy resins, phenolic resins, urea resins, melamine resins, and unsaturated polyester resins, photodegradable photosensitive resins such as diazo resins, and alkyds.

Examples Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Molded fertilizer (ammonium phosphorus, ammonium sulfate, potassium chloride, MgO,
For 1000 g of a mixed molded product of MnO and B ₂ O ₃ , 10 g of watercolor paint (Pentel F watercolor) was dissolved in 50 g of water, and the mixture was mixed while rotating a coater so that the pigment was applied to the entire surface. After drying with hot air, a phenol resin was coated and thermoset to form a film, producing a coated fertilizer uniformly colored red.

Irrigation (100 g
When the relationship between the degree of coloration and the degree of elution of the fertilizer was investigated over time, the color faded as shown in Figure 1, and the lifespan of the fertilizer could be clearly determined visually.

Comparative example 1 Molded fertilizer (ammonium phosphorus, ammonium sulfate, potassium chloride, MgO,
A _coated fertilizer was produced by dissolving 1 g of watercolor paint (Pentel _F watercolor) in 30 g of water and coloring it in the same manner as in Example 1, but the degree of coloring was poor. It was thin and the fading caused by watering was unclear.

Comparative example 2 10g of oil-based pigment (house enamel) and 50% thinner
However, the pigment migrated to the coating resin and remained, and the initial objective could not be achieved.

Effects of the Invention The coated fertilizer of the present invention is a coated fertilizer with a color display in which a colored layer is formed on a molded fertilizer and then coated with a resin in which the coloring components do not dissolve. Now that I can understand it, I can perform additional fertilizing work more accurately.

Since various colors can be selected as the pigments used for the color display, in addition to the fertilization lifespan, other information such as the type of fertilizer and its purpose (target plants, timing of fertilization, etc.) can also be included in the color display. It has the characteristics of a high-quality horticultural fertilizer that is ideal for growing horticultural flower petals, potted plants, agricultural crops, etc.

Also, since the colored pigment is coated with resin, even if you touch it with wet hands, it will not be contaminated by the internal pigment.

Furthermore, the coated fertilizer, which has been discolored due to the leaching of the fertilizing ingredients, can be removed during gardening work, or if it is lightly crushed with fingers, it will break and the leaching of the fertilizing ingredients can be confirmed, so the usability is satisfactory.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the fertilizer weight and the degree of coloring of the coated fertilizer with color display according to the present invention (Example 1), and the scale (a ^* ) on the vertical axis in the figure is CIE
(International Commission on Illumination) Represents the color unit according to the CIELAB method of 1976.

Claims (1)

[Claims] 1. A coated fertilizer with color display, characterized in that it is made by applying a resin coating to a molded fertilizer having a colored layer formed on its surface by applying a water-soluble dye or pigment.