JPS6324960B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a fertilizer for foliar spraying, particularly a highly stable liquid or cream fertilizer containing urea and sucrose fatty acid ester. It is known that spraying urea and sucrose fatty acid ester on growing tea leaves improves the quality of tea leaves, especially low-grade tea leaves such as second-grade tea and third-grade tea. However, sucrose fatty acid ester is extremely poorly soluble in water, and commercially available sucrose fatty acid ester powder is difficult to disperse in water, making it difficult to prepare a uniform spray solution. The present inventors investigated a method for producing a concentrated, storage-stable liquid or cream fertilizer containing urea and sucrose fatty acid ester, and found that urea and sucrose fatty acid ester were heated at a temperature higher than the melting point of the sucrose fatty acid ester. The present invention was completed based on the knowledge that the desired purpose could be achieved by dissolving the product in water. To explain the present invention in more detail, in the present invention, urea and sucrose fatty acid ester are dissolved in water while heating. It is desirable that the concentration of urea and sucrose fatty acid ester in the product be as high as possible.
Usually, the total amount of urea and sucrose fatty acid ester is 20% or more, preferably 30% or more of the total amount. When the proportion of urea and sucrose fatty acid ester increases, the product generally changes from a solution-like state to a cream-like state that is fluid at room temperature, or even a non-flowing cream-like state. This tendency becomes more pronounced as the amount of sucrose fatty acid ester increases. For example, if the total amount of urea and sucrose fatty acid ester in the product is about 33% of the total, the ratio of urea to sucrose fatty acid ester is 94:6.
When the ratio is 84:16, it is in the form of a liquid liquid at room temperature. Even if the ratio of urea and sucrose fatty acid ester is 94:6, if the total amount of both reaches 50% of the total, the product will become creamy with no fluidity at room temperature. Therefore, the total amount of urea and sucrose fatty acid ester is 30~
50% is preferred. Sucrose fatty acid ester is usually used in an amount of 2% or more based on urea. It is preferably used in an amount of 3 to 25%, particularly 3 to 10%. Any commercially available sucrose fatty acid ester can be used. Urea and sucrose fatty acid ester are dissolved in water at a temperature higher than the melting point of the sucrose fatty acid ester. Sucrose fatty acid ester is a mixture and does not have a clear melting point, and generally melts while softening within a range of several degrees Celsius, but in the present invention, the temperature at which sucrose fatty acid ester completely melts, that is, the upper limit of the softening point, is defined as the melting point. shall be. Sucrose fatty acid esters are generally extremely poorly soluble in water at room temperature, but their solubility increases when heated, and above their melting point they form a homogeneous solution with water. When this solution is cooled, sucrose fatty acid ester-
In a two-component system of water, sucrose fatty acid ester precipitates. However, in the presence of urea, the sucrose fatty acid ester does not precipitate, and the whole becomes uniformly liquid or creamy. This substance dissolves easily in water, so
Before use, it may be diluted with water to a predetermined concentration. In addition, when dissolving urea and sucrose fatty acid ester in water while heating, fertilizer components such as potassium chloride and ammonium phosphate, and trace components such as boron and manganese may be added, if desired. According to the present invention, it is possible to easily produce a fertilizer for foliar spraying that has good storage stability and is in the form of a thick liquid or cream. The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited to the following Examples unless it exceeds the gist thereof. Example A total of 100 g of urea and sucrose fatty acid ester (lyotosugar ester) was placed in a 500 ml Erlenmeyer flask, and a predetermined amount of water was added thereto. 70℃
After stirring for 5 minutes to dissolve the mixture, the mixture was allowed to cool. This was stored at 5°C for one week, then allowed to return to room temperature, and diluted with water to form a 1% urea solution. The results are shown in Table 1. The HLB values of the sucrose fatty acid esters used were: HLB = 15 for S1570, HLB = 5 for S570, and HLB = 5 for S970.
is HLB=9.

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Claims (1)

[Scope of Claims] 1. A method for producing a liquid or cream fertilizer for foliar spraying, which comprises dissolving urea and sucrose fatty acid ester in water at a temperature higher than the melting point of the sucrose fatty acid ester. 2. The method for producing a fertilizer for foliar spraying according to claim 1, wherein the weight of urea and sucrose fatty acid ester accounts for 20% or more of the total weight of the liquid fertilizer produced. 3. The method for producing a fertilizer for foliar spraying according to claim 1 or 2, characterized in that it contains 3 to 25% of sucrose fatty acid ester based on urea.