A method for coloring water-soluble fertilizer to improve the effect in the coloring process

Abstract

This invention discloses a water-soluble fertilizer coloring method that enhances the coloring process, belonging to the field of water-soluble fertilizers. The method includes the following steps: S1, adding glycerol, fatty alcohol polyoxyethylene ether, dimethyl sulfoxide, and pure water to a stirring container and starting stirring to obtain a mixed solvent; S2, adding sodium lignosulfonate to the mixed solvent and continuing stirring until the sodium lignosulfonate is completely dissolved to obtain a dispersion; S3, adding potassium pyrophosphate to the dispersion and continuing stirring until the potassium pyrophosphate is completely dissolved to form a mixed solution one, adjusting the pH to form a stable system solution; S4, slowly adding a water-soluble pigment to the stable system solution and continuing stirring to obtain a colorant; S5, mixing the colorant from S4 with fertilizer, wherein the weight of the colorant is 1%~10% of the fertilizer weight, and continuing stirring to obtain a water-soluble fertilizer product. This invention completes coloring solely through material mixing. After coloring, it can significantly improve fertilizer nutrient utilization, enhance crop stress resistance, and also help improve pigment dispersibility and the binding effect between the colorant and fertilizer.

Description

Technical Field

[0001] This invention relates to the field of water-soluble fertilizers, and in particular to a water-soluble fertilizer coloring method that enhances the coloring process. Background Technology

[0002] Water-soluble fertilizers are increasingly widely used in modern agricultural production due to their rapid dissolution, high absorption efficiency, and suitability for water-saving agricultural scenarios such as drip irrigation and sprinkler irrigation. To achieve brand recognition and product differentiation, while also enhancing the product's aesthetic appeal, coloring water-soluble fertilizers has become a standard industry requirement. This necessitates a full range of colors, including black, red, blue, and green, while ensuring that the fertilizer's original water solubility and efficacy remain unaffected. Furthermore, it is hoped that the fertilizer's nutrient utilization efficiency and crop resistance will be further improved.

[0003] Existing water-soluble fertilizer coloring methods include conventional dyeing formulas (pigment carbon black), and methods such as surface modification of carbon black, addition of coupling agents or OP-10, etc. However, existing water-soluble fertilizer coloring methods have the following shortcomings: (1) Common pigment-type dyes have poor compatibility with water-soluble fertilizers, are prone to agglomeration leading to color spots and color differences, and are easily lost and faded in the water-soluble system of fertilizers, resulting in low color fastness.

[0004] (2) Adding coupling agents, surface modifiers, etc., not only increases the complexity of the process and production costs, but may also introduce substances that are difficult to degrade, affect the environment, and even damage the water solubility and nutrient availability of fertilizers.

[0005] (3) Traditional coloring is often combined with production processes such as extrusion, granulation, and spraying. The process coupling is strong, and it is impossible to achieve convenient material mixing and coloring on its own, resulting in poor adaptability.

[0006] (4) Existing coloring formulas are prone to causing fertilizer products to exceed the standards for moisture and water-insoluble matter content, which does not meet industry standards. At the same time, a single formula is difficult to achieve full color range. Dark colors are prone to uneven color development, and light colors are prone to interference from additives, resulting in impure hues. Fifth, existing coloring formulas only meet the coloring requirements and do not have additional functional designs to improve fertilizer utilization efficiency and crop stress resistance. Even if some formulas achieve coloring, they have problems such as poor pigment dispersibility, insufficient binding with fertilizer, and insufficient fertilizer effect. Summary of the Invention

[0007] To address the aforementioned shortcomings, this invention provides a water-soluble fertilizer coloring method that enhances the coloring process. Coloring is achieved solely through material mixing, without involving other production processes such as extrusion, expansion, crushing, or spraying. It can achieve coloring of a full range of colors, including black, red, blue, and green. The water solubility and efficacy of the fertilizer are not affected after coloring, and the coloring is uniform and has high fastness. Furthermore, through material synergy, it can not only significantly improve the utilization rate of fertilizer nutrients and enhance crop resistance, but also help improve the dispersibility of pigments and the binding effect between colorants and fertilizers.

[0008] A coloring method for water-soluble fertilizers that enhances the coloring process includes the following steps: S1, add glycerol, fatty alcohol polyoxyethylene ether, dimethyl sulfoxide and pure water to a stirring container, and start stirring to obtain a mixed solvent; S2, add sodium lignosulfonate to the mixed solvent and continue stirring until the sodium lignosulfonate is completely dissolved to obtain a dispersion; S3, add potassium pyrophosphate to the dispersion, continue stirring until the potassium pyrophosphate is completely dissolved to form mixture one, adjust the pH to form a stable system solution; S4. Slowly add water-soluble pigment to the stable system solution and continue stirring to obtain the colorant; S5, mix the colorant from S4 with the fertilizer, wherein the weight of the colorant is 1% to 10% of the weight of the fertilizer, and continue stirring to obtain a water-soluble fertilizer product; In S1, the stirring speed is 100 r / min to 300 r / min, and the stirring time is 5 min to 15 min; 5 to 10 parts by weight of water-soluble pigment, 5 to 15 parts by weight of sodium lignosulfonate, 20 to 40 parts by weight of glycerol, 1 to 5 parts by weight of potassium pyrophosphate, 1 to 5 parts by weight of fatty alcohol polyoxyethylene ether, 0.5 to 3 parts by weight of dimethyl sulfoxide, and 30 to 100 parts by weight of water; The weight is expressed in grams, kilograms, thousand kilograms, or ten thousand kilograms.

[0009] In one or more optional embodiments of the present invention, in S1, the stirring speed is 100 r / min to 300 r / min, and the stirring time is 5 min to 15 min.

[0010] In one or more optional embodiments of the present invention, in S2, the stirring time is 10 min to 15 min.

[0011] In one or more alternative embodiments of the present invention, in S3, the stirring time is continued for 5 min to 10 min, and the pH is adjusted to 6.5 to 8.5.

[0012] In one or more optional embodiments of the present invention, in S4, the stirring time is continued for 10 min to 20 min at a speed of 200 r / min to 500 r / min.

[0013] In one or more optional embodiments of the present invention, in S4, the water-soluble pigment is one of water-soluble black pigment, water-soluble red pigment, water-soluble blue pigment, and water-soluble green pigment.

[0014] In one or more alternative embodiments of the present invention, in the coloring of water-soluble blue pigment or water-soluble green pigment, the weight ratio of sodium lignosulfonate to potassium pyrophosphate is denoted as M, where M is 3 to 0.5.

[0015] In one or more optional embodiments of the present invention, in S5, the stirring time is 3 min to 10 min, and the stirring speed is 100 r / min to 300 r / min.

[0016] In one or more alternative embodiments of the present invention, in S5, the fertilizer is APP.

[0017] Compared with existing technologies, the invention principles and beneficial effects are as follows: In this invention, dimethyl sulfoxide (DMSO) rapidly carries nutrients from fertilizers through the cuticle and cell membrane of plant leaves, significantly improving fertilizer utilization and enhancing crop stress resistance. Without DMSO, fertilizer nutrient utilization is only at the conventional level, and stress resistance is not improved. At the same time, DMSO has excellent compatibility with each component, especially with [specific component name - missing in original text], which can help improve pigment dispersibility and the binding strength between colorants and fertilizers. Without DMSO, the above effects are generally limited, and the dual optimization of coloring and efficiency cannot be achieved.

[0018] In this invention, for dark colors (black, red), the yellow-brown base color of sodium lignosulfonate is combined with fully water-soluble pigments to form a fuller color rendering effect. At the same time, the macromolecular structure of sodium lignosulfonate encapsulates the pigment particles, and combined with the film-forming adhesion effect of glycerol, it enhances the adhesion and dispersion stability of the pigment on the fertilizer surface. Dimethyl sulfoxide can penetrate into the gaps between pigment particles, assisting sodium lignosulfonate in forming a denser coating layer and improving dispersion stability. Without the addition, the coating layer is loose, the pigment is prone to slight agglomeration, and the color rendering is generally not full.

[0019] In this invention, for light colors (blue and green), by increasing the ratio of potassium pyrophosphate to sodium lignosulfonate, the color-developing structure is altered by combining phosphate ions with the phenolic hydroxyl groups / metal ions in sodium lignosulfonate, thus shielding / reducing yellow interference and ensuring the purity of the light-colored hue. Dimethyl sulfoxide can enhance the compatibility of the reaction between potassium pyrophosphate and sodium lignosulfonate, accelerating the shielding reaction rate. Without its addition, the reaction is insufficient, and light colors are prone to slight graying or yellowing, resulting in a mediocre shielding effect. Simultaneously, dimethyl sulfoxide can reduce the interfacial tension between the colorant and the fertilizer surface, improving the spreadability and bonding strength of the colorant on the fertilizer surface. Without its addition, the interfacial tension is high, making the colorant prone to floating and peeling, resulting in mediocre color uniformity and fastness.

[0020] This invention achieves coloring solely through material mixing, without involving other production processes such as extrusion, puffing, pulverization, or spraying. It can achieve coloring in a full range of colors, including black, red, blue, and green. The water solubility and efficacy of the fertilizer are not affected after coloring, and the coloring is uniform and has high fastness. Furthermore, through material synergy, it can not only significantly improve the utilization rate of fertilizer nutrients and enhance crop resistance, but also help improve the dispersibility of pigments and the binding effect between colorants and fertilizers. Detailed Implementation

[0021] The present invention will be further described below.

[0022] As used in this article: "Prepared from" is synonymous with "comprising". The terms "comprising", "including", "having", "containing", or any other variations thereof as used herein are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0023] The conjunction "composed of..." excludes any unspecified elements, steps, or components. If used in a claim, this phrase makes the claim closed, excluding materials other than those described, except for associated conventional impurities. When the phrase "composed of..." appears in a clause of the body of a claim rather than immediately following it, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0024] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually. For example, when the range “1–5” is disclosed, the described range should be interpreted as including ranges “1–4”, “1–3”, “1–2”, “1–2 and 4–5”, “1–3 and 5”, etc. When numerical ranges are described herein, unless otherwise stated, the range is intended to include its endpoints and all integers and fractions within that range.

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified, specific conditions in the embodiments are performed under conventional conditions or conditions recommended by the manufacturer. Reagents (materials) or instruments (equipment) used without a specified manufacturer are all commercially available conventional products.

[0027] In these embodiments, unless otherwise specified, the portions and percentages are all by weight.

[0028] "Parts by mass" refers to the basic unit of measurement that expresses the mass ratio of multiple components. One part can represent any unit mass, such as 1g or 2.689g. If we say that component A has "a" parts by mass and component B has "b" parts by mass, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it can mean that the mass of component A is aK and the mass of component B is bK (K is any number representing a multiplier). It is important to understand that, unlike the number of parts by mass, the sum of the mass parts of all components is not limited to 100 parts.

[0029] "And / or" is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0030] In the following examples and comparative examples, all materials were purchased from the market, and the ammonium polyphosphate was model APP18-58 with a particle size ≤2mm.

[0031] Example 1 The water-soluble fertilizer colorant formulation of this embodiment consists of the following components: 3 parts by weight of water-soluble black pigment, 12 parts by weight of sodium lignosulfonate, 25 parts by weight of glycerol, 2 parts by weight of potassium pyrophosphate, 3 parts by weight of fatty alcohol polyoxyethylene ether (AEO-9), 2 parts by weight of dimethyl sulfoxide, and 53 parts by weight of pure water.

[0032] A method for coloring a water-soluble fertilizer includes the following steps: S1, add glycerol, fatty alcohol polyoxyethylene ether, dimethyl sulfoxide and pure water into a stirring container, start stirring, the stirring speed is 200 r / min, the stirring time is 8 min, and a mixed solvent is obtained.

[0033] S2, add sodium lignosulfonate to the mixed solvent and continue stirring for 12 minutes until the sodium lignosulfonate is completely dissolved to obtain a dispersion.

[0034] S3, add potassium pyrophosphate to the dispersion, stir for 6 minutes to completely dissolve the potassium pyrophosphate and form mixture one, adjust the pH to 7.5 to form a stable system solution; S4. Slowly add water-soluble black pigment to the stable system solution and stir at 300 r / min for 15 min to obtain the colorant.

[0035] S5, mix the colorant from S4 with APP18-58, wherein the weight of the colorant is 4% of the weight of APP18-58, stir at 200 r / min for 8 min, and obtain a black water-soluble fertilizer product.

[0036] In this embodiment, the colorant has no precipitation, the system is stable, and it spreads well after being mixed with APP18-58. The finished product has no color spots or color difference, the black color is full, and it is firmly bonded with APP18-58.

[0037] Comparative Example 1 The difference from Example 1 is as follows: In this comparative example, the water-soluble fertilizer colorant formulation does not contain dimethyl sulfoxide, and the fatty alcohol polyoxyethylene ether is 5 parts by weight.

[0038] In this comparative example, a small amount of pigment precipitated after the colorant was left to stand for 24 hours. The spreadability after mixing with APP18-58 was average, the finished product had slight color spots, the black color was light and the fullness was average, and some APP18-58 particles had floating color on the surface.

[0039] Example 2 The difference from Example 1 is as follows: In this embodiment, the water-soluble fertilizer colorant formulation does not contain fatty alcohol polyoxyethylene ether, and the dimethyl sulfoxide content is 5 parts by weight.

[0040] In this embodiment, the colorant system is stable and free from precipitation and stratification. After being mixed with APP18-58, the coloring is uniform and the adhesion is firm. The finished product has no color difference or spots, and the fertilizer effect and stress resistance are significantly improved.

[0041] Comparative Example 2 The difference from Example 1 is as follows: In this comparative example, in the water-soluble fertilizer colorant formulation, 2 parts by weight of dimethylformamide (DMF) were used to replace 2 parts by weight of dimethyl sulfoxide.

[0042] In this comparative example, the colorant was evenly dispersed without agglomeration, mixed quickly with APP18-58, and the finished product had no color spots or color difference, with a full red color and no floating color phenomenon.

[0043] Example 3 The difference compared to Example 1 is as follows:

[0044] In this embodiment, in the water-soluble fertilizer colorant formulation, 3 parts by weight of water-soluble red pigment are used to replace 3 parts by weight of water-soluble black pigment.

[0045] In this embodiment, the colorant is evenly dispersed without agglomeration, mixes quickly with APP18-58, and the finished product has no color spots or color differences, the red color is full and there is no floating color phenomenon.

[0046] Comparative Example 3 The difference compared to Example 1 is as follows: In this comparative example, in the water-soluble fertilizer colorant formulation, 3 parts by weight of water-soluble blue pigment replaced 3 parts by weight of water-soluble black pigment.

[0047] In this comparative example, the stability of the coloring system is generally poor. The blue hue is easily affected by the base color of sodium lignosulfonate, resulting in slight yellowing and graying. The coloring uniformity and fastness are also generally poor.

[0048] Example 4 Compared to Comparative Example 3, the difference is: In this embodiment, the water-soluble fertilizer colorant formula is as follows: 3 parts by weight of water-soluble blue pigment, 6 parts by weight of sodium lignosulfonate, 25 parts by weight of glycerol, 4 parts by weight of potassium pyrophosphate, 3 parts by weight of fatty alcohol polyoxyethylene ether (AEO-9), 2 parts by weight of dimethyl sulfoxide, and 53 parts by weight of pure water.

[0049] In this embodiment, the colorant system is stable and has excellent shielding effect. After being mixed with APP18-58, the finished product has no color spots or color difference, the blue hue is pure, and there is no graying or yellowing.

[0050] Comparative Example 4 The difference compared to Example 1 is as follows: In this comparative example, in the water-soluble fertilizer colorant formulation, 3 parts by weight of water-soluble green pigment replaced 3 parts by weight of water-soluble black pigment.

[0051] In this comparative example, the green hue is impure, prone to impurities and yellowing, the pigment dispersion is poor, and the binding effect with fertilizer is mediocre, failing to achieve pure green coloring.

[0052] Example 5 Compared to Comparative Example 4, the difference is: In this embodiment, the water-soluble fertilizer colorant formula is as follows: 3 parts by weight of water-soluble green pigment, 5 parts by weight of sodium lignosulfonate, 25 parts by weight of glycerol, 5 parts by weight of potassium pyrophosphate, 3 parts by weight of fatty alcohol polyoxyethylene ether (AEO-9), 2 parts by weight of dimethyl sulfoxide, and 53 parts by weight of pure water.

[0053] In this embodiment, the colorant has good dispersibility and excellent shielding effect. It is evenly mixed with APP18-58, and the finished product has no color spots or color differences, a pure green hue, and no interference from other colors.

[0054] Comparative Example 5 The water-soluble fertilizer colorant formula of this comparative example consists of the following components: 3 parts by weight of water-soluble black pigment and 83 parts by weight of pure water.

[0055] A method for coloring a water-soluble fertilizer includes the following steps: S1. Add water-soluble black pigment and pure water to a mixing container, turn on the stirrer, stir at a speed of 300 r / min for 10 min to obtain the colorant.

[0056] S2, mix the colorant from S1 with APP18-58, wherein the weight of the colorant is 4% of the weight of APP18-58, stir at 200 r / min for 8 min, and obtain a black water-soluble fertilizer product.

[0057] In this comparative example, the colorant exhibited extremely poor stability, was prone to precipitation and stratification, and showed severe uneven coloring and significant fading, which adversely affected the fertilizer's water solubility and fertilizer efficacy.

[0058] Comparative Example 6 The water-soluble fertilizer colorant formula of this comparative example consists of the following components: 3 parts by weight of water-soluble black pigment, 25 parts by weight of glycerol, and 58 parts by weight of pure water.

[0059] S1. Add water-soluble black pigment, glycerol and pure water to a stirring container, turn on the stirring and stir at a speed of 300 r / min for 10 min to obtain the colorant.

[0060] S2, mix the colorant from S1 with APP18-58, wherein the weight of the colorant is 4% of the weight of APP18-58, stir at 200 r / min for 8 min, and obtain a black water-soluble fertilizer product.

[0061] In this comparative example, the colorant exhibited moderate dispersibility and stability, poor color uniformity and fastness, and did not enhance fertilizer efficiency or crop resistance.

[0062] The water-soluble fertilizer products of Examples 1-4 and Comparative Examples 1-5 were subjected to performance tests. The test items included color uniformity, system stability, moisture content, water-insoluble content, color fastness (natural exposure for 15 days), water solubility, fertilizer efficiency retention rate, fertilizer nutrient utilization rate, and crop stress resistance (drought resistance / cold resistance). The test methods referred to the water-soluble fertilizer industry standards HG / T 5939-2021 and NY / T 1107, as well as conventional agricultural fertilizer field / laboratory testing methods. Among them, fertilizer nutrient utilization rate and crop stress resistance were determined by field plot test method, and system stability was observed after the colorant was left to stand for 72 hours. The results of color uniformity, system stability (72 hours), moisture content, water-insoluble content, and fading after 15 days of exposure are shown in Table 1 below. The results of water solubility, fertilizer efficiency retention rate, fertilizer nutrient utilization rate, and crop stress resistance (drought resistance / cold resistance) are shown in Table 2 below.

[0063] Table 1 Table 2 From Tables 1 and 2, we can see that: Comparing Example 1 with Comparative Examples 1-3, Example 1 showed superior performance in all aspects, with uniform coloring, stable system, and indicators far exceeding industry standards. It also significantly improved fertilizer nutrient utilization (more than 15% higher than the group without additives) and significantly enhanced crop stress resistance, achieving the dual effects of coloring and efficiency enhancement. In contrast, Comparative Examples 1-3 only achieved basic coloring effects. Although the moisture and water-insoluble matter indicators still met the standards, the coloring uniformity, system stability, and color fastness were all average. Furthermore, there was no improvement in fertilizer nutrient utilization or crop stress resistance, making them general coloring formulas with only one function.

[0064] Comparing Example 1 and Comparative Examples 4-5, Comparative Examples 4 and 5 had problems such as uneven coloring, exceeding the standard, severe fading, and reduced fertilizer efficiency, and had the worst performance.

[0065] Comparing Comparative Example 3 with Example 4 and Comparative Example 5, for light-colored systems, by reasonably adjusting the ratio of sodium lignosulfonate to potassium pyrophosphate, the yellow background interference of sodium lignosulfonate can be effectively shielded, making the blue and green coloring purer, more uniform, and free from yellowing and graying. This significantly improves the hue purity and appearance quality of light-colored systems, solving the technical problem that traditional light-colored water-soluble fertilizers are easily affected by additives and have impure hues.

[0066] As can be seen from Examples 1-5, through the synergistic effect of various water-soluble pigments with sodium lignosulfonate, glycerol, potassium pyrophosphate, fatty alcohol polyoxyethylene ether, dimethyl sulfoxide and water, the performance in all aspects is excellent, the coloring is uniform, the system is stable, the indicators are far superior to the industry standard, and the fertilizer nutrient utilization rate is greatly improved (more than 15% higher than the group without additives), and the crop's stress resistance is significantly enhanced, achieving the dual effect of coloring and efficiency enhancement.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A coloring method for water-soluble fertilizers that enhances the coloring process, characterized in that, Includes the following steps: S1, add glycerol, fatty alcohol polyoxyethylene ether, dimethyl sulfoxide and pure water to a stirring container, and start stirring to obtain a mixed solvent; S2, add sodium lignosulfonate to the mixed solvent and continue stirring until the sodium lignosulfonate is completely dissolved to obtain a dispersion; S3, add potassium pyrophosphate to the dispersion, continue stirring until the potassium pyrophosphate is completely dissolved to form mixture one, adjust the pH to form a stable system solution; S4. Slowly add water-soluble pigment to the stable system solution and continue stirring to obtain the colorant; S5, mix the colorant from S4 with the fertilizer, wherein the weight of the colorant is 1% to 10% of the weight of the fertilizer, and continue stirring to obtain a water-soluble fertilizer product; 5 to 10 parts by weight of water-soluble pigment, 5 to 15 parts by weight of sodium lignosulfonate, 20 to 40 parts by weight of glycerol, 1 to 5 parts by weight of potassium pyrophosphate, 1 to 5 parts by weight of fatty alcohol polyoxyethylene ether, 0.5 to 3 parts by weight of dimethyl sulfoxide, and 30 to 100 parts by weight of water; The weight is expressed in grams, kilograms, thousand kilograms, or ten thousand kilograms.

2. The water-soluble fertilizer coloring method with enhanced effect during the coloring process according to claim 1, characterized in that, In S1, the stirring speed is 100 r / min to 300 r / min, and the stirring time is 5 min to 15 min.

3. The water-soluble fertilizer coloring method with enhanced efficiency during the coloring process according to claim 1, characterized in that, In S2, continue stirring for 10 to 15 minutes.

4. The water-soluble fertilizer coloring method with enhanced effect during the coloring process according to claim 1, characterized in that, In S3, continue stirring for 5 to 10 minutes and adjust the pH to 6.5 to 8.

5.

5. The water-soluble fertilizer coloring method with enhanced efficiency during the coloring process according to claim 1, characterized in that, In S4, continue stirring for 10-20 minutes at 200-500 rpm.

6. The water-soluble fertilizer coloring method with enhanced efficiency during the coloring process according to claim 1, characterized in that, In S4, the water-soluble pigment is one of the following: water-soluble black pigment, water-soluble red pigment, water-soluble blue pigment, and water-soluble green pigment.

7. The water-soluble fertilizer coloring method with enhanced effect during the coloring process according to claim 6, characterized in that, In the coloring of water-soluble blue or water-soluble green pigments, the weight ratio of sodium lignosulfonate to potassium pyrophosphate is denoted as M, where M is 3 to 0.

5.

8. The water-soluble fertilizer coloring method with enhanced effect during the coloring process according to claim 1, characterized in that, In S5, continue stirring for 3 to 10 minutes at 100 to 300 rpm.

9. The water-soluble fertilizer coloring method with enhanced effect during the coloring process according to claim 1, characterized in that, In S5, the fertilizer is APP.

Images