Polyurethane Coating Agent for Slow Release Fertilizer

Polyurethane Coating Agent for Slow Release Fertilizer

Product Overview

Polyurethane Coating Agent for Slow Release Fertilizer is a modified polymer coating material developed for the production of slow-release and controlled-release fertilizers.

It forms a dense and uniform coating layer on fertilizer granules, helping regulate nutrient release, extend fertilizer efficiency and improve nutrient utilization.

The coating formulation can be customized according to fertilizer type, target release period, crop requirements, local climate, soil conditions and production process.

Main Applications

This product is suitable for the production of:

• Slow-release fertilizer

• Controlled-release fertilizer

• Polyurethane-coated urea

• Coated compound fertilizer

• High-tower compound fertilizer

• Conventional compound fertilizer

• Organic fertilizer granules

Technical Specifications

The above data represents typical test results and may vary slightly depending on the production batch.

Key Product Advantages

1. Customized Nutrient Release Period

The coating formulation supports customized nutrient release periods from 30 to 180 days.

Available release periods include:

• 60 days

• 90 days

• 120 days

• Other customized periods from 30 to 180 days

The nutrient release profile can be adjusted to match different crop growth cycles and soil conditions.

2. Uniform and Durable Coating

The product forms a dense and uniform coating film with strong adhesion to fertilizer granules.

The coating helps reduce:

• Cracking

• Peeling

• Powdering

• Moisture absorption

• Fertilizer caking during storage

It is suitable for fertilizer products requiring storage stability and long-distance transportation.

3. Good Processing Performance

The coating agent has good fluidity and sprayability, allowing it to be evenly distributed over fertilizer granules.

Under recommended processing conditions, initial film formation can be completed in approximately 5 minutes, with full curing in approximately 1 hour.

Actual film formation and curing time depend on temperature, coating dosage, fertilizer granule quality and production equipment.

4. Compatible with Common Coating Equipment

The product can be used with common fertilizer coating equipment, including:

• Rotary drum coating equipment

• Fluidized-bed coating equipment

• Mixing and polishing equipment

• Standard hot-coating production lines

No highly complex production system is required. Specific process parameters can be adjusted according to the customer’s existing equipment.

5. Economical Coating Dosage

For coated urea production, the recommended coating-agent dosage is approximately:

8–10 kg per metric ton of urea

The actual dosage should be determined according to:

• Target nutrient release period

• Fertilizer particle size

• Surface condition of fertilizer granules

• Coating equipment

• Production temperature

• Required coating thickness

6. Improved Fertilizer Efficiency

The coating layer helps control the release of nitrogen and other nutrients, reducing rapid nutrient release at the early stage and insufficient nutrient supply at the later stage.

It can help:

• Extend fertilizer efficiency

• Improve nutrient utilization

• Reduce fertilizer application frequency

• Reduce labor requirements

• Reduce nutrient loss through leaching and volatilization

Reference Performance of Coated Urea

Polyurethane-coated urea produced with a suitable formulation and coating process may achieve the following reference indicators:

These values are reference indicators rather than guaranteed specifications for every production condition. Final coated-fertilizer performance depends on raw fertilizer quality, coating dosage, formulation, equipment and process control.

Recommended Application Process

A typical hot-coating process includes the following steps:

1. Screen and prepare the fertilizer granules.

2. Heat the fertilizer granules to the required processing temperature.

3. Spray the coating agent evenly onto the rotating fertilizer granules.

4. Continue mixing to ensure uniform surface coverage.

5. Complete coating, polishing and film formation.

6. Allow sufficient curing before cooling and packaging.

The appropriate temperature, spraying rate, coating time and curing conditions should be determined through production testing.

Customized Formulation Service

Customized coating formulations are available according to:

• Fertilizer type

• Target release period

• Crop type

• Climate conditions

• Soil conditions

• Fertilizer particle size

• Existing production equipment

• Customer production process

• Destination market requirements

Customers can provide fertilizer samples and target release requirements for technical evaluation.

Information Required for Quotation

For a faster quotation and technical recommendation, please provide:

• Type of fertilizer to be coated

• Target release period

• Fertilizer particle size

• Current coating equipment

• Required monthly or annual quantity

• Packaging requirements

• Destination country and port

• Sample testing requirements

Contact Us

Contact us for:

• Product specifications

• Technical data

• Sample evaluation

• Application guidance

• Customized coating formulations

• Commercial quotation

We welcome inquiries from fertilizer manufacturers, coated-urea producers, agricultural chemical distributors and international fertilizer importers.