Clarity is one of the most important performance indicators of epoxy resin, especially in applications like river tables, art, furniture coating, and high-end consumer products. Yet one of the most common issues users face is cloudy epoxy, also known as haze.

Cloudiness can happen before, during, or after curing. Understanding the root causes helps users prevent defects—and helps OEM partners choose more reliable formulations. At CNMI Industrial Corporation, we engineer epoxy systems with enhanced clarity and haze resistance, supported by rigorous R&D and quality control.

1. What Is Cloudiness in Epoxy Resin?

Cloudiness appears as:

• a milky appearance

• microbubbles suspended in the resin

• a foggy or matte finish

• uneven clarity across the piece

This haze indicates that the resin–hardener reaction or physical conditions are not optimal.

2. Why Epoxy Turns Cloudy: The Scientific Causes

① Moisture Contamination

Moisture is the largest contributor to haze.

When epoxy reacts with water, it forms:

• microbubbles

• amine blush

• loss of clarity

High humidity accelerates this effect.

Typical symptoms:

• milky or foggy appearance

• oily surface or blush

• patchy clarity

CNMI’s moisture-resistant hardener systems reduce this risk.

② Low Temperature (Below 20°C / 68°F)

Cold environments increase viscosity.

This causes:

• trapped microbubbles

• uneven mixing

• crystallization-like cloudiness

• slow cure → delayed clarity

CNMI uses anti-crystallization additives in cold-resistant formulations.

③ Incorrect Mixing

Improper mixing creates:

• unmixed resin streaks

• pockets of microbubbles

• reaction imbalance

Common problems caused by poor mixing:

• streaky cloudiness

• milk-like swirls

• partial cure

CNMI formulations include balanced viscosity for easier mixing.

④ Contaminated Containers or Surfaces

Residues of:

• oils

• dust

• silicone

• alcohol

• moisture

…can cause haze, separation, or fisheyes.

This is especially common in furniture coating and flooring applications.

⑤ Old or Expired Resin

Aging epoxy may show:

• partial crystallization

• yellowing haze

• phase separation

This leads to cloudiness even before mixing.

CNMI’s shelf-life engineering and anti-crystallization processes significantly extend clarity retention.

⑥ Incorrect Pour Depth or Exotherm

Pouring too thick causes overheating.

This leads to:

• micro-cracking

• white veining

• heat-induced haze

Deep-pour systems require low exotherm chemistry—CNMI’s HL210 is engineered for this purpose.

3. How CNMI Prevents Cloudiness

At CNMI Industrial Corporation, clarity engineering involves multiple layers of control:

✔ High-purity raw materials

Reduces impurities that cause haze.

✔ Controlled viscosity curves

Ensures proper flow and bubble release.

✔ Anti-crystallization stabilizers

Prevents cloudiness at low temperatures.

✔ Moisture-resistant curing agents

Limits amine blush and humidity haze.

✔ Vacuum degassing and fine filtration

Removes microscopic particulates and air pockets.

✔ Batch-level clarity testing

Each production lot is inspected against clarity standards (APHA color index).

These steps ensure that CNMI epoxy remains crystal-clear in both thin and deep applications.

4. How to Avoid Cloudiness as a User

CNMI recommends the following best practices:

① Keep workspace at 22–26°C (72–79°F)

Ideal temperature for clarity.

② Maintain humidity below 65%

Reduces moisture haze and blush.

③ Warm resin before mixing

Improves flow and releases microbubbles.

④ Mix thoroughly for 2–3 minutes

Scrape sides and bottom.

⑤ Use clean, dust-free containers

Avoid contamination.

⑥ Use appropriate pour thickness

Deep pours require deep-pour formulations.

Following these guidelines ensures optimal clarity during curing.

5. Applications Where Clarity Matters Most

Clarity is critical for:

• river tables

• casted art

• jewelry and molds

• furniture coatings

• deep-pour transparent panels

• premium OEM branded kits

CNMI’s clarity-focused epoxy systems—HL210, HL521, and TC110—are engineered to meet global premium standards.

Conclusion: Cloudiness is Preventable With Correct Chemistry and Technique

Cloudy epoxy is a common but preventable issue. By understanding the scientific causes—moisture, temperature, mixing, contamination, and curing dynamics—users and OEM partners can achieve consistently clear results.

At CNMI Industrial Corporation, our formulations are engineered to avoid haze through advanced chemistry, precise QC testing, and global application expertise.

Whether used for art, furniture, flooring, or composites, CNMI epoxy systems deliver crystal clarity and professional performance worldwide.