PHOENIX Painting Diluent - 16.9 Fl Oz./ 500ml Oil Brush Cleaner, Odorless Oil Paint Thinner, Mineral Spirits Refined Solvent, Painting Medium for Artists

What it is and where it fits

I tested the Phoenix diluent over several weeks as both a paint thinner and a daily brush cleaner in a small, well-ventilated studio. It’s a refined, hydrotreated petroleum distillate—essentially an odorless mineral spirits–type solvent—geared toward oil painters who want to reduce fumes without sacrificing performance. The pitch is simple: lower odor than traditional turpentine or standard mineral spirits, gentle on brushes, and reliable for thinning and cleanup.

In practice, it behaved exactly like a clean, high-grade OMS should: predictable evaporation, consistent thinning power, and minimal residue. It isn’t a medium in the “adds oil/binder” sense; it’s a solvent. You can use it as part of a medium when combined with linseed, stand, or an alkyd, but on its own it will make paint leaner, faster-setting, and a bit more matte.

Packaging and handling

The 16.9 fl oz (500 ml) bottle is a sensible size for regular use—enough to fill a small brush washer and still have reserve for decanting. The cap sealed tight, and I didn’t experience any seepage in transit or storage. The bottle pours cleanly; I still recommend decanting into a lidded brush washer or a small glass jar for daily use, both to minimize evaporation and to keep sediment contained.

I’d love a narrower spout or a flip-top for micro-pours, but that’s a minor convenience note more than a performance issue.

Thinning performance on the palette

I put the solvent through a few common scenarios:

• Blocking in/underpainting: For the first lean layers, a small amount (roughly 5–15%) loosened the paint body without breaking the film or streaking. Earth colors and titanium white leveled well and set quickly to a soft-matte surface, which is ideal for subsequent “fat over lean” work. There was a subtle acceleration to set time owing to solvent evaporation, but it didn’t create uneven drying patches.

• Glazes and scumbles: Straight solvent produces very lean, matte glazes that can look a touch chalky with high-titanium mixes. For richer, more integrated glazes, I had better results cutting it with a little linseed or stand oil (for example, 1 part oil to 2–3 parts solvent). This balanced flow and transparency while keeping the layer sufficiently lean early in the painting.

• Edge control: A drop or two on the brush helped feather edges and pull long lines without the drag you get from thicker, oilier mixes. This was particularly helpful with synthetics, which tend to snap more and can benefit from a touch of slip.

• Pigment integrity: Colors maintained vibrancy at modest dilution. At heavier dilutions (washes approaching “soup”), pigment can sit more on the surface and look slightly desaturated—typical of any solvent-only wash. That’s not a knock on the product; it’s an expected outcome of removing binder rather than adding it.

Overall, the Phoenix diluent felt consistent—not too “hot,” not sluggish. It’s less aggressive than turpentine, which I appreciated around delicate previous layers.

Brush and tool cleaning

As a brush cleaner, it was effective for fresh paint and the usual end-of-session cleanup:

• Hog bristle: Paint released quickly without stripping the natural oils from the bristles. After a quick swish and wipe, a follow-up with brush soap restored the bristles’ shape with no sign of brittleness.

• Synthetic: No clouding or softening. The solvent cut through alkyd-boosted paints as long as the paint was still fresh. For semi-dried tips, it loosened material but couldn’t fully rescue neglected brushes—which is par for the course; no gentle solvent will reverse hard-set paint.

• Palette knives/palettes: Cut through film cleanly, leaving no oily residue. I still recommend a final wipe with a rag and a touch of soap for glass palettes to eliminate smears.

If you’re used to turpentine’s bite on semi-dried paint, this will feel milder. That’s by design. For hardened gunk, a dedicated brush restorer or a stronger cleaner is still the right tool.

Odor, air quality, and safety

“Odorless” in the solvent world means “very low odor,” not “no VOCs.” In my 10 x 12 ft studio with a window cracked and a small fan running, I didn’t notice any discernible smell during a full day’s session. In a closed room, there was a faint solvent note detectable only at the jar mouth. Compared to hardware-store mineral spirits or turpentine, the difference in ambient comfort was significant.

It conforms to ASTM D4236, which addresses chronic hazard labeling for art materials. That’s reassuring, but standard solvent safety still applies:

• Use with ventilation.
• Keep containers closed when not in use to minimize evaporation.
• Dispose of solvent-soaked rags in a sealed, fire-safe container; they’re flammable.
• Let sediment settle and decant clean solvent to extend life; dispose of sludge per local hazardous-waste guidelines.

Compatibility and film considerations

• Paint films: Over-reliance on straight solvent can under-bind paint, leading to weak films and sinking-in. This is true of all solvents. The Phoenix diluent behaved responsibly in normal use—no unusual sinking beyond what I’d expect from lean layers. If you see persistent dull patches, oil out with a minimal oil/solvent mix or work “fatter” with subsequent passes.

• Varnish/retouch: It’s fine for degreasing an old palette or cleaning a test area, but I wouldn’t use any solvent of this type for thinning final varnishes unless specifically recommended by the varnish manufacturer. For retouch varnish, follow the varnish instructions.

• Medium building: It plays nicely with linseed or stand oil for a lean to moderate medium. For faster drying, add an alkyd to the mix rather than increasing solvent. The solvent simply thins; it doesn’t accelerate oxidative curing like an alkyd would.

• Supports and grounds: On acrylic gesso, wash layers sat evenly without pronounced beading. On oil-primed linen, the first pass absorbed as expected; no unusual staining.

Practical tips

• Start small: Add a drop or two into your paint pile rather than dipping a wet brush into a bath. It’s easy to overshoot into soupy territory.

• Two-jar method: One jar for the initial dirty rinse, one for a cleaner final rinse. Let both settle overnight; decant the clear solvent back into the clean jar and wipe out the pigment sludge.

• Preserve brushes: Always finish with brush soap and water. The solvent will remove paint; the soap will reset the bristles.

• Manage “sinking in”: If a layer dries dull, lightly oil out with a 1:2 or 1:3 oil-to-solvent mix before proceeding.

Value

You’ll likely pay more per ounce than you would for hardware-store mineral spirits or bulk turpentine. In return, you get a cleaner, lower-odor studio experience and a solvent that won’t bully your paints or your brushes. The 500 ml bottle lasted me through multiple medium-sized canvases with daily cleanup, especially when I reused decanted solvent. If you paint frequently in an indoor studio, around family, or in shared spaces, the premium makes sense.

If you only need an aggressive cleaner for hardened tools, this isn’t the most economical choice; a purpose-made brush restorer or a cheaper, stronger solvent might be better for that narrow task. But for the painter’s everyday workflow—mixing, laying in, cleaning as you go—it hits the mark.

What I liked

• Truly low odor in real-world studio use
• Predictable thinning power without excessive bite
• Gentle on both natural and synthetic brushes
• Minimal residue; easy to reuse through settling/decanting
• Reliable, leak-free bottle with a sensible volume

What could be better

• A narrower or controlled-pour spout would reduce waste
• Not ideal for rescuing semi-hardened brushes (a tradeoff of its gentler profile)
• As with all good OMS, it’s pricier than basic solvents

Recommendation

I recommend the Phoenix diluent to oil painters who want a dependable, low-odor solvent for daily studio use. It thins paint cleanly, respects pigment integrity at reasonable dilutions, and makes brush cleanup straightforward without harsh fumes. While it won’t replace a dedicated restorer for badly neglected brushes and it does cost more than hardware-store alternatives, the comfort and consistency it brings to the workflow are worth the premium. If you paint indoors, value predictable handling, and care about brush longevity, this belongs on your bench.