HF-B3 is a modified aromatic amine epoxy curing agent that combines low viscosity with fast curing. It is widely used in epoxy flooring, mortars, composites, and casting applications. Notably, this product offers excellent cost‑performance and is particularly suitable for epoxy flooring primers.

1. Product Overview of HF-B3

HF-B3 belongs to the modified aromatic amine category. Through chemical structure optimisation, it significantly reduces viscosity while improving low‑temperature curing capability compared to conventional aromatic amines.

Typical physical properties:

• Colour (Gardner): ≤ 18

• Viscosity at 25°C: 100–300 mPa·s

• Active hydrogen equivalent: 95 g/eq

• Density at 25°C: 1.085–1.105 g/cm³

• Recommended dosage (EEW = 190): 50 phr

Typical handling properties:

• Gel time (100 g mix at 25°C): 40–60 minutes

• Hardness Shore D (24 h at 25°C): 78

These data show that HF-B3 achieves reasonably fast room‑temperature curing (40–60 min gel time) and reaches Shore D 78 within 24 hours, making it suitable for applications requiring efficiency.

2. Technical Characteristics of Aromatic Amine Curing Agents

Aromatic amines are compounds where amino groups (–NH₂) are directly attached to an aromatic ring (e.g., benzene, naphthalene). Compared to common aliphatic or cycloaliphatic amines, they exhibit the following scientific features:

• Excellent substrate permeability:
  Aromatic amine curing agents generally have low molecular weight and moderate polarity, allowing them to penetrate porous substrates such as concrete, mortar, or wood. This results in improved adhesion and a more compact cured layer, which is especially beneficial for flooring primers and penetrating sealers.

• Chemical and corrosion resistance:
  The cured network is rich in aromatic rings, providing excellent resistance to organic acids, organic solvents, and weak acids/bases. HF-B3’s data sheet specifically highlights “especially good electrical and mechanical properties against organic acids,” which directly correlates with the aromatic amine structure.

3. Conclusion

HF-B3 is a scientifically designed modified aromatic amine epoxy curing agent that successfully balances the high heat and chemical resistance of traditional aromatic amines with low viscosity, good permeability, and room‑temperature curing. Its technical data clearly show that when used at 50 phr with an epoxy resin of EEW ≈190, it provides a working window of about 40–60 minutes at 25°C and rapidly builds a Shore D hardness of 78 within 24 hours. With its high cost‑performance, excellent permeability, and suitability for epoxy flooring primers, HF-B3 is a technically reliable and economically attractive choice for engineering systems that require both organic acid resistance and application efficiency.