Short answer
Posca does not make a chalk marker. Posca’s range page lists only water-based paint markers, from the PC-1MR to the PC-17K. The Uni chalk marker is the uni-ball Chalk Marker PWE-5M (a medium bullet tip) sold under the uni-ball name. Use liquid chalk for chalkboards and menu boards you wipe often; use Posca for windows, art and signs, knowing Posca says its paint wipes off smooth surfaces with a damp rag but can become encrusted over time.
Does Posca make chalk markers?
No. Posca’s range page lists ten tips in seven shapes and 66 colors, all water-based paint markers: PC-1MR, PC-1MC, PC-3M, PC-5M, PC-7M, PC-8K, PC-17K, the brush PC-5BR and PCF-350, and the PCM-22. None is a chalk marker. The confusion is understandable: Posca is used on many of the same surfaces as liquid chalk, and the same Uni company sells a chalk marker under the uni-ball name.
Posca vs liquid chalk markers
Posca paint markers compared with liquid chalk markers
| Posca paint marker | Liquid chalk marker | |
|---|---|---|
| What it is | Water-based pigment paint | Water-based chalk ink |
| On glass and windows | Wipes off with a damp rag, per Posca; can encrust over time | Made to wipe off with water |
| On chalkboards | May stain or ghost on porous boards; test first | Made for non-porous chalkboards and menu boards |
| On paper, wood, stone | Permanent, per Posca | Not designed for it; soaks in |
| Opacity | Strong, layerable | Bright, usually a single layer |
| Best for | Art, signs that stay up a while, window art | Menus and boards you rewrite often |
Posca’s window advice is in its FAQ: a damp rag cleans designs off a window or display case, but pigments can become encrusted and stop being erasable. For seasonal window art, either works; for a menu board rewritten daily, chalk is the better tool.
The Uni chalk marker: uni-ball PWE-5M
The uni-ball Chalk Marker is sold as the PWE-5M with a medium bullet tip; Amazon listings title it at 2.5 mm, in white, gold and multi-color packs, from a single pen to a dozen whites. Like other liquid chalk markers, it is meant for non-porous surfaces such as boards, windows, mirrors and whiteboards. Other chalk marker brands are compared on chalk markers, white chalk markers and window chalk markers; Sharpie’s version is covered on Sharpie chalk markers.
Which to use where
- Café menu boards, rewritten daily: liquid chalk marker.
- Seasonal window art: either; Posca gives stronger color, chalk wipes off more easily. Take Posca designs down when the season ends.
- Car windows: a chalk marker sold for car windows; test on a corner.
- Black paper art, “chalkboard style” lettering: Posca white on black paper or card, which is permanent and will not smudge. See white Posca markers.
- A real chalkboard you want to keep clean: test any marker on a corner. Painted chalkboards are often porous enough to ghost.
Removing chalk marker and Posca from boards and glass
- Start with water
Wipe with a damp microfiber cloth. Most liquid chalk and fresh Posca come off glass this way.
- Add a little soap
A drop of dish soap in warm water lifts stubborn spots.
- Use a plastic scraper on glass
For older, encrusted paint on glass only, a plastic razor scraper helps. Avoid scraping boards.
- Test cleaners
Try any stronger cleaner on a hidden corner first, especially on chalkboard paint.
The full method, including ghosting on chalkboards, is in how to remove chalk marker. For where Posca is permanent and where it is not, see are Posca markers permanent.
Uni chalk markers and Posca on Amazon
Uni’s liquid chalk markers and the Posca whites people use instead, each listing checked by hand.
-
uni-ball PWE-5M Chalk Marker, medium bullet, white, pack of 12
Uni’s own liquid chalk marker in white, the color used most on boards.
- Medium bullet
- White, 12 pens
-
uni-ball PWE-5M Chalk Marker, bullet tip, gold, 2.5 mm
Gold for headings and borders on menu boards and windows.
- 2.5 mm
- Gold
-
Uni-Ball liquid chalk marker, 8 pieces
An eight-color pack of Uni liquid chalk markers.
- Chalk marker
- 8 pens
-
Posca PC-17K paint marker, extra broad 15 mm, white
Posca’s widest white for window art that wipes off later, per Posca’s FAQ.
- 15 mm
- White
-
Posca PC-5M white, 3 count
Medium white Posca for chalkboard-style lettering on black paper and card.
- 1.8 to 2.5 mm
- White
Each pick links to an Amazon listing we checked by hand. Prices, colors and pack sizes change on Amazon, so check the listing before you buy. As an Amazon Associate we earn from qualifying purchases.
Questions people ask
What type of paint are POSCA markers?
Posca calls them water-based paint markers with stable pigments. Many retailers call them acrylic markers. They are opaque, layerable once dry, permanent on porous surfaces like paper, wood and stone, and erasable on smooth surfaces like glass, according to Posca. They are paint, not chalk.
Will chalk markers work on paper?
They will mark paper, but they are not made for it. Liquid chalk is designed for non-porous surfaces such as chalkboards, glass and whiteboards, where it wipes off. On porous paper it soaks in, cannot be erased, and can look streaky. For paper, use a paint marker such as Posca or a regular art marker.
Why are POSCA markers so expensive?
Posca has not published a cost breakdown. Likely factors are the pigment paint, the valve and mixing ball inside each pen, reversible tips on the fine and medium sizes, and a formula Posca says has been unchanged since 1983. Independent testing rated Posca the best pump-action marker overall, which supports demand.
Do Posca pens rub off?
On smooth surfaces like glass and windows, yes: Posca says a damp rag cleans its designs off, which is why it is popular for window art. On porous surfaces like paper, wood and stone, Posca says the paint is permanent. Posca also warns window designs can become encrusted over time and stop being erasable.
Can I use Posca on a chalkboard?
Test first. A chalkboard’s surface can be porous, and Posca says its paint is permanent on porous surfaces, so it may not wipe off cleanly and can ghost. For boards you rewrite often, use liquid chalk markers made for chalkboards, such as the uni-ball PWE-5M, and test those on a corner too.
Sources
Last reviewed 2026-10-12. Specs and availability change; check the listing before you buy.