Semi-Refined Wax, commonly referred to as Semi-Refined Paraffin Wax, is a petroleum-based wax produced from slack wax through partial refining processes such as deoiling, filtration, and mild hydrotreatment. It represents an intermediate grade between crude/slack wax and fully refined paraffin wax.
With a controlled oil content typically between 3% and 7%, semi-refined wax offers an optimal balance of physical stability, flexibility, appearance, and cost efficiency. It is one of the most widely consumed wax grades globally for industrial and commercial applications where ultra-high purity is not essential.
Key Characteristics
Moderate Oil Content (3–7%)
Retained oil enhances flexibility, plasticity, and ease of blending, improving workability in candle molding, rubber compounding, and coatings.
Stable & Controlled Melting Range
Typical melting point of 54°C – 66°C ensures uniform melting, controlled cooling, and dimensional stability in finished products.
Good Transparency & Appearance
Light white to off-white color with lower odor than slack wax, suitable for decorative and visible end products.
Smooth Texture & Surface Finish
Provides even coating, improved gloss, and reduced surface defects.
Cost–Performance Balance
More economical than fully refined wax while offering significantly better quality than slack wax.
Typical Mechanical & Physical Properties
| Property | Typical Range |
|---|---|
| Melting Point | 54°C – 66°C |
| Oil Content | 3% – 7% |
| Penetration @ 25°C | 15 – 30 dmm |
| Density @ 25°C | 0.88 – 0.92 g/cm³ |
| Viscosity @ 100°C | 3 – 6 cSt |
| Flash Point | 180°C – 220°C |
| Color | Light white to off-white |
| Odor | Mild petroleum |
Refining & Manufacturing Process
Slack Wax Production
Generated during solvent deoiling of lubricating oil base stocks.
Partial Deoiling
Oil content reduced to the targeted 3–7% range.
Filtration & Clay Treatment
Improves color, clarity, and removes residual impurities.
Mild Hydrotreatment (Optional)
Reduces odor and sulfur while improving oxidation stability.
Unlike fully refined wax, deep hydro-finishing is avoided, allowing some oil retention for better flexibility and processing ease.
Available Grades (Indicative)
| Grade | Melting Point |
|---|---|
| Semi-Refined Wax | 54–56°C |
| Semi-Refined Wax | 58–60°C |
| Semi-Refined Wax | 60–62°C |
| Semi-Refined Wax | 64–66°C |
Available Forms & Packaging
Physical Forms
✔ Slabs / Blocks (1–5 kg)
✔ Granules / Pellets
✔ Flakes (on request)
✔ Molten bulk supply
Packaging Options
✔ Poly-lined cartons
✔ HDPE bags
✔ Drums
✔ Jumbo bags
✔ Export-grade palletized packing
Applications of Semi-Refined Wax
Candle Manufacturing
Smooth surface finish, controlled burning, and good scent retention for household, pillar, and decorative candles.
Packaging Industry
Moisture-resistant coatings for paperboard, corrugated boxes, and wrappers.
Rubber & Tyre Industry
Processing aid and anti-ozonant surface protection.
Cosmetics & Personal Care
Used as thickener, emollient, and texture modifier in basic formulations.
PVC & Plastics
Lubricant for extrusion and molding processes.
Adhesives & Sealants
Controls viscosity and setting time in hot-melt systems.
Matches, Boards & Polishes
Matchstick coating, plywood waterproofing, shoe and floor polish.
Advantages
✔ Cost-effective for large-scale use
✔ Balanced flexibility and hardness
✔ Easy to process and blend
✔ Consistent melting behavior
✔ Wide grade availability
Limitations
⚠ Higher oil content than fully refined wax
⚠ Mild petroleum odor in sensitive applications
⚠ Not suitable for pharmaceutical or food-grade use
Semi-Refined vs Fully Refined Paraffin Wax
| Parameter | Semi-Refined Wax | Fully Refined Wax |
|---|---|---|
| Oil Content | 3–7% | ≤ 0.5% |
| Purity | Moderate | Very high |
| Odor | Mild | Odorless |
| Cost | Lower | Higher |
| Applications | Industrial, candles | Pharma, food, cosmetics |
| Flexibility | Higher | Lower |
Storage & Handling Guidelines
✔ Store in a cool, dry, covered area
✔ Avoid direct sunlight and excessive heat
✔ Stack cartons properly to prevent deformation
✔ Melt slowly using indirect heating to avoid discoloration
Semi-Refined Wax is a versatile, economical, and reliable paraffin wax grade that bridges the gap between slack wax and fully refined wax. Its balanced oil content, stable melting range, and smooth appearance make it a preferred choice for candles, packaging, rubber, PVC, adhesives, and general industrial applications where performance consistency and cost efficiency are essential.