Semi-Refined Wax, commonly referred to as Semi-Refined Paraffin Wax, is a petroleum-based wax obtained 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 combines good physical stability, flexibility, and cost efficiency, making it one of the most widely consumed wax grades globally for both industrial and commercial applications.
This grade is preferred where high purity is not critical, but consistent performance, appearance, and ease of processing are required.
Key Characteristics – Detailed Explanation
Moderate Oil Content (3–7%)
Retained oil enhances: Flexibility, Plasticity, Ease of blending
Improves workability in candle molding, rubber compounding, and coatings.
Stable & Controlled Melting Range
Typical melting point: 54°C – 66°C
Ensures: Uniform melting behavior, Controlled cooling, Dimensional stability in finished products
Good Transparency & Appearance
Light white to off-white color
Lower odor compared to slack wax
Suitable for decorative and visible end products
Smooth Texture & Surface Finish
Provides: Even surface coating, Improved gloss, Reduced surface defects
Cost–Performance Balance
More economical than fully refined wax
Higher quality than crude/slack wax
Ideal for high-volume consumption industries
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 (Saybolt) | #ERROR! |
| Odor | Mild petroleum |
Refining & Manufacturing Process
Slack Wax Production: Generated during solvent deoiling of lubricating oil base stocks
Partial Deoiling: Reduces oil content to targeted range (3–7%)
Filtration & Clay Treatment: Improves color and clarity, Removes residual solids and impurities
Mild Hydrotreatment (Optional): Reduces odor and sulfur, Enhances oxidation stability
Unlike fully refined wax, deep hydro-finishing is avoided, allowing some oil to remain for better flexibility and processing ease.
Available Grades (Indicative)
Semi-refined wax is often supplied in multiple melting points:
54–56°C
58–60°C
60–62°C
64–66°C
Each grade is selected based on climate, application, and end-product requirements.
Available Forms & Packaging
Physical Forms: Slabs / Blocks (1–5 kg), Granules / Pellets, Flakes (on request), Molten bulk supply (industrial)
Packaging Options: Poly-lined cartons, HDPE bags, Drums, Jumbo bags, Export-grade palletized packing
Applications of Semi-Refined Wax
1. Candle Manufacturing: Most common application. Provides: Smooth surface finish, Controlled burning, Good scent retention. Used for: Pillar candles, Household candles, Decorative candles.
2. Packaging Industry: Moisture-resistant coatings, Paperboard and corrugated boxes, Waxed paper and wrappers.
3. Rubber & Tyre Industry: Processing aid in rubber compounding, Anti-ozonant surface protection, Improves flexibility and durability.
4. Cosmetics & Personal Care: Used in: Creams, Hair products, Basic cosmetic formulations. Acts as a: Thickener, Emollient, Texture modifier (Not typically used in high-end or pharma-grade cosmetics).
5. PVC & Plastic Processing: Lubricant for extrusion and molding, Improves surface finish, Reduces friction during processing.
6. Adhesives & Sealants: Blended into hot-melt adhesives, Controls viscosity and setting time.
7. Matches & Board Manufacturing: Matchstick coating, Plywood and particle board moisture resistance.
8. Polishes & Waterproofing Products: Shoe polish, Floor polish, Rust prevention coatings.
Advantages of Semi-Refined Wax
✔ Cost-effective for large-scale use
✔ Good balance of flexibility and hardness
✔ Easy to process and blend
✔ Consistent melting behavior
✔ Wide availability and grade options
Limitations
⚠ Higher oil content than fully refined wax
⚠ Slight petroleum odor in sensitive applications
⚠ Not suitable for pharmaceutical or food-grade uses
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 high temperatures
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 raw 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, especially where cost efficiency and performance consistency are critical.