Gilsonite in Paints and Coatings: An Overview

Gilsonite is a classic resin for black industrial paints and protective coatings. It dissolves in common solvents and oils and gives tough, glossy, chemical-resistant films.
Key benefits
- Deep black colour without large amounts of pigment
- High gloss
- Water, acid and alkali resistance
- Good adhesion to steel, concrete and wood
- Low cost compared with many synthetic resins
Typical products
- Black enamels and japans
- Primers and anti-corrosion paints
- Wood stains and preservatives
- Underbody coatings
- Roof and tank coatings

How it is used
Gilsonite is dissolved in aromatic or aliphatic solvents, drying oils or alkyds, then combined with fillers and other resins.
Where gilsonite fits among coating resins
| Resin | Typical use | Gilsonite’s role |
|---|---|---|
| Drying oils / alkyds | Enamels, primers | Adds hardness, gloss, black colour |
| Bitumen | Protective black coatings | Raises softening point |
| Hydrocarbon resins | General industrial | Partial replacement in dark coatings |
Formulation tips
- Pre-dissolve gilsonite in solvent or hot oil to make a varnish.
- Add pigments and fillers after the gilsonite is fully dissolved.
- Adjust driers in oil and alkyd systems; gilsonite can slow oxidation slightly.
Typical properties of gilsonite coatings
Deep black colour, high gloss when fresh, good water and acid resistance, and strong adhesion to blasted steel and concrete. Gilsonite films can chalk under strong UV over time, so topcoats are used for long-term exterior appearance.
See paint grade gilsonite and gilsonite solvent solubility guide.
Recommended product
Ink & Paint Grade Gilsonite
| Property | Typical value | Test method |
|---|---|---|
| Appearance | Dark brown–black powder | Visual |
| Softening point (R&B) | 150 – 180 °C | ASTM D36 |
| Ash content, max | 3 % | ASTM D3174 |
| Moisture, max | 1 % | ASTM D95 |
| Solubility in toluene, min | 99 % | ASTM D2042 |
| Particle size | 200 – 600 mesh | Sieve |
| Typical dosage | Ink varnish: 20–40 % in oil | |
| Packing | 25 kg paper bags with PE liner, palletized. | |
Typical values. The final specification is confirmed in the COA of each shipment.

