JPH013090A - How to color granular fertilizer substances - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present substance relates to a method for coloring granular fertilizer substances.

[Conventional technology]

Conventionally, granular fertilizer substances, such as granular urea, have been colored, and the methods include (1) mixing a coloring agent with the urea itself, and (2) adding a liquid or powder dye or pigment to the surface of the granular urea. (3) A method of coating the surface of granular urea with a coating material containing a coloring agent (Japanese Unexamined Patent Application Publication No. 50-134871), etc. are known.

[Problems to be solved by conventional technology and invention]

However, (1) is undesirable because it requires a large amount of coloring agent, resulting in high costs, and the equipment and operations required to change the color tone become complicated. Method (3) is disclosed in Japanese Unexamined Patent Application Publication No. 1983-1973, which requires less amount of particles, but has the disadvantage that particles easily peel off due to mutual friction, etc.
134871, it is used when the film is thick in order to slow the release of fertilizer by utilizing the moisture-proofing properties of the film.

Furthermore, if the purpose is simply to color granular fertilizer, a large amount of coating material is used to form a film, which is uneconomical, and the amount of colorant used inevitably increases, leading to high costs. If the thickness of the coating is reduced by simply using a colored coating without any special performance, the strength of the coating will weaken and the particles will easily peel off due to friction between particles during transportation, mixing, etc., and the coloring will be lost. There were drawbacks.

[Means and effects for solving the problems] The present inventors have conducted extensive research in order to solve the above-mentioned problems of the prior art, and have applied an aqueous solution of a condensate of urea and formaldehyde to which a coloring substance has been added to the particle surface. The present invention was completed by discovering that granular fertilizer substances can be colored by treatment.

That is, the method for coloring granular fertilizer substances of the present invention is characterized by treating the particle surface with an aqueous solution of a condensate of urea and formaldehyde to which a coloring substance has been added.

The present invention will be explained in more detail below.

In the method of the present invention, the granular fertilizer material to be treated is a mixture of lime superphosphate, ammonium phosphate, ammonium chloride, etc. and urea, and granular urea. There are no particular restrictions on the method for producing these granular fertilizer substances; for example, in the case of granular urea, a method is used in which molten urea is granulated in a granulation tower (Japanese Patent Application Laid-Open No. 5O-1) 4
380), or a method of spray granulating molten urea in a fluidized state with urea pellets and prilled urea (Japanese Patent Application Laid-Open No. 56-762)
36), or a method of granulating with a dish-type granulator is used.

In the present invention, the surface of these granular fertilizer substances is coated with a condensate of urea and formaldehyde (hereinafter referred to as LIF) containing a coloring agent.
(referred to as condensate). First, a coloring agent is mixed and dissolved in an aqueous solution of UF condensation proboscis in advance, and the surface of the granular fertilizer substance is treated with the coloring agent to coat the granular fertilizer with color, thereby achieving a clear and strong coloring. The method of coating the particle surface may be any conventionally used known method, such as immersion method, transfer coating method using a rotating drum or dish granulator, or fluidized bed method using a jet tank or jet tower. Among these methods, preferred are methods in which the material is transferred using a rotating drum or colored and deposited while being fluidized in a spouted bed. For example, UP condensate water made by heating granular fertilizer material and adding a coloring agent to its surface? A homogeneous film can be formed on the particle surface by spraying the 8 liquid and transferring it for a certain period of time using a rotating drum, or by spraying it while flowing it in a spouted bed.

Is the coloring agent used in the present invention OF condensate water? Any dye may be used as long as it can be melted and mixed into the liquid, but water-based dyes are usually preferably used. Furthermore, food additive dyes, pigments, etc. can also be used if necessary.

In the present invention, by colored coating with tlF metal shrinkage, it is possible to form a coating that adheres strongly without peeling, compared to conventionally used polyolefins, vinyl acetates, etc. Even very thin coatings can cover the entire surface of the granular fertilizer material with a uniform thickness. As a result, it is possible to form a sufficiently strong coating film even if it is thin enough to be impossible to form with other conventional coating materials, or even if it is formed, it is too weak to withstand practical use. It is possible to prevent the color from peeling off on the surface of the substance.

Therefore, compared to the case where other coating materials are used, the amount of LIF condensate used can be reduced, the equipment for the coating process can be made smaller, and the operating time can also be shortened.

As the aqueous solution of the OF condensate used in the present invention, one with a solid content of 40 to 80 weight percent, which is prepared from 1.2 to 6 moles of formaldehyde per mole of urea, can preferably be used. A coloring agent is added and dissolved in this. At this time, it is preferable to mix a predetermined amount of the coloring agent and knead it with a small amount of water, and then add this to the aqueous solution of the OF metal shrinkage. Next, 1 to 2% by weight of ammonium chloride, hydrochloric acid, formic acid, ammonium sulfate, etc., are added as a curing agent to the aqueous solution of the tIF metal product.

Conditions for the coating treatment include, for example, in the case of granular urea, the particle temperature is 40 to 80°C, preferably 60 to 70°C, and the amount of the treatment agent added is 0.05 to 0.4 with respect to the granular urea.
% by weight, preferably 0.1 to 0.2 weight %, is sprayed, and the treatment time is 3 to 1) minutes, preferably 5 to 8 minutes, by transfer or flow treatment to uniformly cause a coating curing reaction.

The above is sufficient to bring out the effects of the present invention, but additionally coating with wax is necessary to improve performance such as wear resistance, anti-caking property, anti-corrosion property, and hardness. Highly preferred. In this case, taking granular urea as an example, the above OF
After the shrinkage coating treatment, molten wax is subsequently sprayed at a particle temperature of 50-60'C and 0.05-0.0% per granular urea.
5% by weight, preferably 0.1-0.3% by weight, and rolled for 3-8 minutes, preferably 3-5 minutes to ensure uniform coating.

The wax used in this case is preferably petroleum-based paraffin wax or microcrystalline wax with a melting point in the range of 50°C to 60°C, and furthermore, the surface may be sprinkled with fine particles of silicic acid or the like. further improves the effectiveness of the wax coating process.

〔Example〕

The present invention will be explained in more detail with reference to Examples, but the scope of the present invention is not limited thereby.

Example 1 1 kg of granular urea with a diameter of 2 to 3 cylinders is placed in a rotating mixing drum and tumbled while maintaining the temperature at 60''C.

On the other hand, 0.1 g of Vertical Red No. 2 (manufactured by Daiwa Kasei Co., Ltd.) was dissolved in an aqueous solution of 10 g of OF metal shrinkage, and NH was used as a hardening agent.
Mix 4Cl l wt%.

This solution was applied to the above granular urea as a colored coating agent at a rate of 0.2
% and transfer for 5 minutes to color.

Through the above operations, granular urea whose surface is colored and coated in red is obtained.

100g of the obtained colored granular urea was loaded into a vSS horse rotating drum equipped with a baffle plate inside, and transferred, and the time it took for the color to peel off due to rolling friction was measured.It took more than 5 hours for the color to peel off. It cost.

Comparative Example 1 1) The other operations were performed in the same manner as in Example 1, without using the F shrink material. What was the color after 30 minutes? ,+I AI
did.

Comparative Example 2 Coloring III was formed in the same manner as in Example using the same amount of various coating materials in place of the UF shrink material, and a color peeling test was conducted. Table 1 shows the results.

Table 1 APP: Accurate Polypropylene [Effects of the Invention] The granular fertilizer material colored by the method of the present invention has its color very firmly fixed on the surface and does not peel off even under severe conditions. The thickness of the colored coating layer made of tlF shrink metal is only about 1 to 2 μm, and if a layer of the same thickness was made of other materials, it would peel off in a much shorter time.
The colored layer of the granular fertilizer material disappears. This effect is due to the fact that the film of IF shrinkage has a stronger adhesion to the granular fertilizer material than any other material, and the colorant is firmly held within this strong film. This is because there is.

The effect of the present invention lies first in its strong coloring, and as a result of its excellent abrasion resistance, it can be stored for a long time, transported,
The color will not peel off or disappear during other handling. This is completely impossible with methods using other colored coating layers. Moreover, since the color does not disappear even in bulk blending operations with other components, it can be handled quickly and easily.

Secondly, the amount of coating layer used is overwhelmingly small compared to other coating materials, so costs are low and the equipment can be small, and since the coating layer is thin, a relatively small amount of coloring agent is required. Furthermore, this coating layer naturally decomposes after fertilization, so there is no risk of causing problems such as pollution.

In the present invention, the colored coating process is only one step, and the equipment thereof is extremely simple. Therefore, even when changing the coloring agent, cleaning of the device is performed in a timely manner, and the switching operation can be performed in a short time. In addition to the effects related to coloring as described above, as a result of using the UFh1 compound as a coating material, great advantages such as an anti-caking effect, moisture resistance, and improvement in particle hardness can be obtained at the same time.

The colored granular fertilizer material produced by the method of the present invention can be used to change the color and concentration to indicate the component composition and blend ratio with other component particles, which is convenient for management, and can be used as a commercial product. The aesthetics are also good.

can increase value.

Patent applicant: Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] (1) A method for coloring granular fertilizer substances, which comprises treating the particle surface with an aqueous solution of a condensate of urea and formaldehyde to which a coloring substance has been added.