This article systematically introduces the concept, characteristics, functions, application fields, selection considerations, and common problem-solving measures of TGIC powder coatings. Special emphasis is placed on their key functions to help readers better understand what TGIC powder coatings are, their unique features, and their primary applications.
What Is TGIC Powder Coating?
TGIC powder coating is a thermosetting powder coating that uses TGIC (Triglycidyl Isocyanurate) as the curing agent. It is typically formulated with polyester resin and forms a dense, durable coating through heat melting, cross-linking, and curing processes.Characteristics of TGIC Powder Coatings
The main characteristics of TGIC powder coatings are as follows:1. Excellent Weather Resistance
TGIC powder coatings offer exceptional UV resistance and can withstand prolonged outdoor exposure without chalking or fading, making them a leading choice for durable outdoor coatings.
2. Outstanding Mechanical Properties
The coating is hard and impact-resistant while maintaining excellent flexibility, allowing it to pass bending tests without cracking.
3. Good Chemical Resistance
It resists acid rain, detergents, and common solvents, effectively protecting substrates from chemical corrosion.
Functions of TGIC Powder Coatings
The primary functions of TGIC powder coatings include the following:1. Protective Functions
Weather Protection
Protects substrates such as aluminum and steel from UV radiation, rain, and environmental degradation, preventing aging, chalking, and corrosion.
Mechanical Protection
The hard and impact-resistant coating withstands scratches, impacts, and deformation caused by metal bending.
Chemical Protection
Provides resistance against acid rain, detergents, salt spray, and other corrosive chemicals.
2. Decorative Functions
TGIC powder coatings provide long-lasting gloss and color stability, maintaining an attractive appearance without significant fading or gloss loss over time.
Applications of TGIC Powder Coatings
TGIC powder coatings are widely used in the following industries:1. Construction and Outdoor Facilities
Aluminum doors and windows
Curtain walls
Railings
Street light poles
Highway guardrails
These applications require long-term UV resistance and corrosion protection.
2. Transportation Industry
Automotive wheels
Vehicle frames
Roof racks
Truck components
Agricultural machinery
Excavators and construction equipment
These applications require impact resistance and wear resistance.
3. Household Appliances
Air conditioner outdoor units
Refrigerator side panels
Ovens
Washing machine panels
These products require both weather resistance and heat resistance.
4. General Industrial Products and Furniture
Outdoor fitness equipment
Bicycle frames
Metal office furniture
Storage racks
Electrical equipment enclosures
How to Choose TGIC Powder Coatings
When selecting TGIC powder coatings, many users are unsure how to make the right choice. Based on our industry experience, we recommend focusing on the following factors:1. Select According to the Service Environment
Extreme Outdoor Applications
(Building curtain walls, automotive wheels)
Choose super-durable weather-resistant grades that comply with standards such as AAMA 2604.
General Outdoor Applications
(Fitness equipment, guardrails)
Choose standard industrial-grade coatings that provide a good balance between performance and cost.
2. Select According to Process Requirements
Curing Temperature
Verify that the curing oven can achieve temperatures of 180–200°C while considering the thermal mass of the workpiece.
Film Thickness
For standard applications, a film thickness of 60–80 μm is recommended. For thicker coatings (>100 μm), TGIC systems offer significant advantages due to their lower tendency to develop pinholes.
Mechanical Performance
If the coated part requires stamping or bending, request reverse-impact and cupping test data from the supplier.
3. Consider Safety and Regulatory Compliance
Toxicity Control
TGIC raw materials may cause sensitization. Choose products that comply with relevant standards such as GB/T 27807-2011 and ensure adequate ventilation and protective measures in the coating workshop.
Common Problems and Solutions for TGIC Powder Coatings
The following are the most common issues encountered during the use of TGIC powder coatings, along with recommended solutions based on our industry experience.1. Cratering and Surface Pits
Symptoms
Circular crater-like depressions or small pits appear on the coating surface.
Main Causes
Inadequate substrate degreasing
Oil or water contamination in compressed air
Cross-contamination from different powder coatings
Solutions
Thoroughly clean the pretreatment line to ensure substrate cleanliness.
Install efficient oil-water separators and air filtration systems after the air compressor.
Completely clean the spray booth, powder hopper, and recovery system when changing powder types.
2. Pinholes
Symptoms
Numerous small visible holes appear on the coating surface.
Main Causes
Excessive coating thickness in a single application (especially above 120 μm in TGIC systems)
Insufficient or ineffective degassing agent (such as benzoin)
Powder particle size is too fine
Solutions
Control coating thickness within the recommended range (typically 60–80 μm).
Consult the supplier regarding the appropriate amount of degassing agent.
Optimize particle size distribution to reduce excessive fine particles.
3. Orange Peel
Symptoms
The coating surface exhibits slight waviness resembling orange peel.
Main Causes
Poor leveling properties of the powder coating
Excessive coating thickness
Uneven oven temperature or overly rapid heating
Solutions
Work with the supplier to optimize leveling agents and filler systems.
Adjust spraying parameters to achieve uniform film thickness.
Inspect the oven circulation system to ensure consistent temperature distribution.
4. Low Gloss or Incomplete Curing
Symptoms
The coating appears dull, and powder may even rub off by hand.
Main Causes
Insufficient curing temperature or curing time
Severe shortage of TGIC curing agent in the formulation
Solutions
Measure the actual workpiece temperature during curing, especially for heavy parts.
Increase curing temperature or extend curing time.
Request batch quality inspection reports from the supplier to verify TGIC content.
5. Brittle Film and Poor Impact Resistance
Symptoms
The coating cracks or peels during bending or impact testing.
Main Causes
Excessive TGIC content resulting in overly high cross-link density
Mismatch between polyester resin and TGIC curing agent (acid value or reactivity incompatibility)
Solutions
Strictly control the TGIC ratio in the formulation.
The TGIC dosage can be calculated using the following formula:
TGIC Amount = (Polyester Acid Value × Polyester Weight) / (561 × TGIC Epoxy Value)
Use polyester resin and TGIC systems recommended by the same supplier to ensure compatibility.
If you encounter difficult-to-solve issues during the use of powder coatings, please feel free to contact us for professional technical support. We are committed to working together with customers to solve coating challenges and promote the development of the powder coating industry.
We hope this article provides a professional and reliable reference regarding powder coating technology. We sincerely welcome any inquiries related to powder coating performance, industry standards, application methods, precautions, or any other related topics.
Please feel free to leave a message or contact us directly. We would be pleased to provide detailed product information, demonstration videos, and customized coating solutions to help you gain a comprehensive understanding of our products and their advantages.
