In industrial coatings, inks, plastics, and touch-up paint systems, aluminum paste plays a crucial role in imparting luster and protection to metals. However, many failures—such as decreased gloss, gas generation, black spots, or poor orientation—are not product quality issues, but rather caused by improper use. Silver Rocket Metal Pigments Ltd. shares key steps to ensure stable and reliable aluminum paste performance.

Why Aluminum Paste Fails: Understanding the Core Mechanisms

Aluminum paste (including solvent-based and water-borne grades) is sensitive to moisture, pH changes, and aggressive additives. When improperly handled, aluminum flakes can oxidize, react, or agglomerate—leading to coating defects.
Understanding these mechanisms allows users to prevent over 90% of failures long before production begins.

1. Step One: Store Aluminum Paste Correctly to Prevent Early Deterioration

Avoid Moisture Exposure

Aluminum flakes react with water, forming hydrogen gas. Even small humidity levels can cause foaming or pressure build-up.
Key rules:

• Keep containers sealed tightly.

• Store between 5–35°C in a dry, shaded area.

• Rotate inventory (FIFO).

Temperature Stability Matters

High heat accelerates oxidation, while low temperatures cause solvent separation.

• Do NOT expose drums to sunlight or heaters.

• Warm gently (25–30°C) before production if paste becomes too thick.

Never Mix Old and New Batches

Different moisture levels or solvent ratios may trigger unwanted reactions.

2. Step Two: Use Proper Dispersion Techniques (The Most Overlooked Step)

Avoid High-Shear Mixing

Excessive shear breaks the protective coating of aluminum flakes.
Result: Loss of brightness, darkening, gas formation.

Recommended:

• Low-speed stirring.

• Add aluminum paste after all resin and solvents are fully mixed.

Choose Compatible Solvents and Resins

Some polar solvents or alkaline additives can attack the aluminum.

• Test small batches before mass production.

• For water-based systems, use water-based aluminum paste or SiO₂-coated aluminum powder.

Never Add Aluminum Paste Directly to Water

This mistake is responsible for many customer complaints.
Always pre-mix with resin or solvent first.

3. Step Three: Control Your Formulation Environment

Check pH Before Adding Aluminum Paste

Alkaline conditions (pH > 8) accelerate reactions.
For water-based systems, maintain:

• pH 6.5–7.5

Avoid Corrosive Additives

Amine-rich dispersants, strong surfactants, or metal catalysts can destabilize aluminum flakes.

Use Anti-Oxidation Additives When Needed

Some formulations require stabilizers for long storage periods.

Applications & Comparison: How Correct Handling Improves Real-World Results

Correct aluminum paste handling improves:

• Metallic gloss

• Orientation

• Storage stability

• Safety

• Production efficiency

Follow the Right Steps and Avoid 90% of Aluminum Paste Problems

Most aluminum paste failures are preventable. By storing correctly, dispersing gently, controlling pH, and using compatible materials, you ensure stable performance and longer shelf life.

For expert guidance or customized grades, contact Silver Rocket Metallic Pigment Co., Ltd.

Email: info@silverocket.com
Website: https://www.silverocket.com/