Bitumen 85/100 — Specification, Production & Applications
Bitumen 85/100 is a soft paving grade widely specified in South and Southeast Asian road programmes, combining workability with tighter ageing limits than comparable soft grades.
Where Bitumen 85/100 sits among the penetration grades
Penetration is measured as the depth in tenths of a millimetre that a standard needle penetrates the binder in five seconds at 25 °C under a 100 g load, to ASTM D5. A lower number means a harder binder. The scale above runs from hard on the left to very soft on the right.
What defines Bitumen 85/100
Penetration of 85 to 100 at 25 °C makes this a soft binder, but its ageing requirements are those of a premium grade: loss on heating capped at 0.8 per cent and retained penetration at 52 per cent, considerably tighter than the 1.5 and 40 permitted for 70/100. That combination is what distinguishes it.
The values that matter
It is a common choice where a soft binder is needed for workability or climate but the specifying authority is unwilling to accept the wider ageing tolerances that usually accompany softness. The 250 °C flash point minimum, equal to the hard grades rather than the soft ones, points the same way.
How Bitumen 85/100 is produced
Refining route
Production is straight-run vacuum residue at a moderate to shallow cut depth. The distinguishing feature is not the cut but the crude selection and the process control: reaching 85 to 100 penetration while still holding loss on heating below 0.8 per cent requires a residue with low volatile carry-over, which not every slate provides at that softness.
Blend and release control
Where the base residue is too volatile, the correction is either a different crude or a longer stripping stage rather than blending, since blending a soft stream in tends to raise volatile content further. Release testing focuses on the thin film oven results, which are the binding constraint for this grade.
Bitumen 85/100 specification
| Property | Test method | Unit | Requirement |
|---|---|---|---|
| Density @ 25 °C | ASTM D70 | g/cm³ | 1.01–1.06 |
| Penetration @ 25 °C, 100 g, 5 s | ASTM D5 | ×0.1 mm | 85–100 |
| Softening point, ring and ball | ASTM D36 | °C | min 42 |
| Ductility @ 25 °C | ASTM D113 | cm | min 100 |
| Loss on heating | ASTM D6 | wt % | max 0.8 |
| Retained penetration after heating | EN 1426 | % | min 52 |
| Solubility in trichloroethylene | ASTM D2042 | wt % | min 99 |
| Flash point, Cleveland open cup | ASTM D92 | °C | min 250 |
| Spot test | AASHTO T102 | — | negative |
A certificate of analysis accompanies every shipment. Independent inspection by SGS, Intertek or an equivalent surveyor can be arranged at the buyer instruction and account.
Where Bitumen 85/100 is used
South Asian road programmes
National and state highway works where 85/100 is the specified penetration grade.
Tropical surface dressing
Chip seals and surface treatments in humid tropical climates.
Asphalt plant supply
Hot mix production where a softer binder suits the aggregate and mix design.
Cold and warm mix asphalt
Applications where lower mixing temperatures are targeted for energy or emissions reasons.
Pavement maintenance
Overlays, patching and rehabilitation on existing networks.
Emulsion feedstock
Base binder for cationic and anionic bitumen emulsions.
Handling and application temperatures
Working temperatures follow the binder viscosity rather than the grade designation alone. The ranges below are typical starting points for Bitumen 85/100 and should be confirmed against the mix design.
| Operation | Typical range | Control note |
|---|---|---|
| Bulk storage | 145–165 °C | Circulate to avoid local overheating at the coils |
| Pumping and transfer | 145–165 °C | Confirm line tracing before transfer begins |
| Hot mix asphalt mixing | 145–160 °C | Per mix design, not per binder alone |
| Compaction | 125–145 °C | Cease rolling below the lower figure |
| Maximum sustained heating | below 180 °C | Above this, oxidative hardening accelerates sharply |
Drummed material should be reheated in a controlled oven or hot room rather than by direct flame. Localised overheating hardens the binder at the drum wall and can take a compliant parcel out of specification before it reaches the mixer.
Available packing for Bitumen 85/100
| Packing | Net weight | Loading per 20 ft FCL | Typical use |
|---|---|---|---|
| New steel drum | 150 / 180 / 185 / 200 kg | 110 drums, 20.35 MT at 185 kg | Smaller parcels, sites without bulk storage |
| Jumbo bag | 1 MT | 20 MT | Lower packing cost, requires melting facility |
| Flexitank / bitutainer | 20–22 MT | 1 unit | Bulk economics without a bulk vessel |
| Bulk vessel | by parcel | heated tanker | Terminal to terminal, largest volumes |
As a Bitumen 85/100 supplier Bitumen Asphaltive ships on CFR, CIF and FOB terms with commercial invoice, packing list, bill of lading, certificate of origin and certificate of analysis.
Questions about Bitumen 85/100
Why choose 85/100 over 70/100 when the penetration windows overlap?
Because the ageing limits differ substantially. 85/100 caps loss on heating at 0.8 per cent and requires 52 per cent retained penetration; 70/100 permits 1.5 per cent and 40 per cent. If the project cares about how the binder behaves after mixing rather than only in the tank, 85/100 is the tighter specification.
Is 85/100 equivalent to VG-10?
They are frequently cited as near equivalents and the consistency is comparable, but the two standards measure different things. VG-10 is graded on absolute viscosity at 60 °C under IS 73; 85/100 is graded on needle penetration at 25 °C. A binder can satisfy one and not the other. Where a contract names a viscosity grade, only a viscosity-graded certificate satisfies it.
What softening point should we expect?
A minimum of 42 °C by ASTM D36. There is no upper bound in this specification, so a parcel can be considerably above the minimum and still comply. If the mix design assumes a particular softening point, state it in the enquiry rather than relying on the grade alone.
Does the 250 degree flash point mean it can be heated harder?
No. Flash point is a safety limit, not a working range. Sustained heating above 180 °C accelerates oxidative hardening regardless of flash point, and will take the binder out of specification well before any safety threshold is approached.
The penetration grade range
Penetration windows overlap between adjacent grades, so a single parcel can sometimes satisfy two specifications. Ageing limits and softening point are what separate them.
| Grade | Penetration @ 25 °C | Character |
|---|---|---|
| Bitumen 20/30 | 20–30 × 0.1 mm | Hard |
| Bitumen 30/40 | 30–40 × 0.1 mm | Hard |
| Bitumen 40/50 | 40–50 × 0.1 mm | Medium hard |
| Bitumen 50/70 | 50–70 × 0.1 mm | Medium hard |
| Bitumen 60/70 | 60–70 × 0.1 mm | Medium hard |
| Bitumen 70/100 | 70–100 × 0.1 mm | Medium soft |
| Bitumen 80/100 | 80–100 × 0.1 mm | Medium soft |
| Bitumen 85/100 | 85–100 × 0.1 mm | Medium soft |
| Bitumen 120/150 | 120–150 × 0.1 mm | Soft |
| Bitumen 200/300 | 200–300 × 0.1 mm | Very soft |
Speak to a Bitumen 85/100 supplier
Send quantity in metric tonnes, required packing, destination port and preferred Incoterm. Offers are normally returned within one working day.