The key to color aluminum plates is to choose the right process. Overall, powder coating, liquid coating, electrophoretic coating, and coating processes are the mainstream methods for color aluminum plates at present. Powder spraying has low cost and easy operation; Liquid coating has rich colors and strong adaptability; Electrophoretic coating has good adhesion and uniform film thickness; The coating process can endow aluminum plates with better weather resistance. Different coloring requirements correspond to different process choices, and reasonable use is necessary to achieve the desired effect.

1. Main coloring techniques

1. Powder spraying process

(1) Principle: Powder coating is uniformly attached to the surface of aluminum plate through electrostatic adsorption, and then cured at high temperature to form a coating.
(2) Characteristics:
Rich in colors, capable of achieving various effects such as matte, high gloss, metallic texture, etc
Coating thickness 30-120 μ m, weather resistance 5-10 years
Excellent environmental performance, VOC emissions close to zero
(3) Process flow:
Surface pretreatment (degreasing, rust removal, phosphating)
Electrostatic spraying (voltage 60-80kV)
Curing (180-220 ℃, 10-15 minutes)

2. Fluorocarbon spraying process

(1) Principle: A liquid coating based on polyvinylidene fluoride (PVDF) resin is used to form a coating through air spraying or electrostatic spraying.
(2) Characteristics:
Excellent weather resistance (15-20 years), strong UV resistance
High color retention and resistance to fading
Excellent chemical corrosion resistance
(3) Key parameters:

Parameter project	Technical indicators
coating thickness	25-40 μ m (dual coating)
Curing temperature	230-250℃
Gloss	10-90% (adjustable)
Pencil hardness	≥2H

3. Roller coating process

(1) Principle: The liquid coating is continuously applied to the surface of a moving aluminum coil through a coating roller, and then baked and cured to form a continuous coating.
(2) Characteristics:
High production efficiency, suitable for large-scale continuous production
Excellent coating uniformity, with a thickness deviation of ± 2 μ m
Can achieve special effects such as dual color and wood grain
(3) Equipment requirements:
Coating head accuracy ≤ 0.01mm
Temperature uniformity of baking oven ± 5 ℃
Tension control system accuracy ± 0.5N/mm

4. Electrophoretic coating process

(1) Principle: Under the action of a direct current electric field, charged coating particles migrate and deposit onto the surface of a color aluminum plate to form a coating.
(2) Characteristics:
Good coating permeability, with 100% coverage of edges and corners
High swimming penetration, suitable for complex shaped workpieces
Simple wastewater treatment with obvious environmental advantages
(3) Process conditions:

Project	Parameter range
Voltage	100-300V
Electrophoresis time	1-3 minutes
Tank liquid temperature	25-30℃
Solid fraction	18-22%

2. Process selection suggestions

(1) In the field of building curtain walls, fluorocarbon spraying technology is preferred, as its weather resistance of over 20 years can meet the long-term exposure requirements of high-rise buildings.
(2) In the field of interior decoration, powder coating technology has the highest cost-effectiveness, rich color selection, and meets environmental performance standards.
(3) In the field of home appliance panels, roller coating technology is suitable for large-scale production and can achieve decorative effects such as wood grain and stone grain.
(4) Complex structural components: The electrophoretic coating process ensures uniform coating on all parts, making it particularly suitable for irregular parts such as car wheels.

3. Key points of quality control

(1) Pre treatment quality: The thickness of the phosphating film should be controlled at 2-3 μ m, and there should be no red rust after a salt spray test of ≥ 1000 hours.
(2) Coating thickness: Use an eddy current thickness gauge to ensure compliance with process standards.
(3) Adhesion test: Conduct a grid test according to GB/T 9286 standard to achieve level 0 standard.
(4) Color difference control: detected using a spectrophotometer, with a Δ E value ≤ 1.5 (compared to a standard plate).

4. Development Trends

With the increasing environmental requirements, the proportion of water-based coatings and powder coatings will continue to rise. The application of intelligent equipment such as intelligent spraying robots and online detection systems will promote the development of color aluminum plate coloring technology towards higher efficiency and precision. Meanwhile, the development of functional coatings such as self-cleaning and antibacterial will become a new growth point.
Now, we have learned about various processes for color aluminum plates, whether it is powder coating that pursues cost-effectiveness, liquid coating that values color richness, electrophoretic coating that emphasizes adhesion, or coating processes that pursue weather resistance, all of which can make aluminum plates emit a unique charm. If you are troubled by color aluminum plates, you may want to boldly try these techniques according to your own needs. I believe that with the help of appropriate craftsmanship, the aluminum plate in your hand can become a masterpiece of color and embark on a colorful new journey!