Clear, frosted, mirror, and translucent acrylic are appearance options, not four different plastics. Most display work uses poly(methyl methacrylate), usually called PMMA or acrylic. The finish changes how much light passes through, how private the sheet looks, and how printing and edges read. It does not, by itself, set strength, outdoor life, or food-contact status.
Short answer
Use clear acrylic when the object or insert behind the sheet must stay readable. Use frosted acrylic when you want diffused light and less glare, and when fine text behind the sheet is not required. Use mirror acrylic when the face should reflect the room and hide what is behind it. Use translucent acrylic when you want color and light to pass, but not a sharp view through the part.
Those four choices cover most retail signs, menu stands, brochure holders, and solid display blocks. A sample in the intended thickness is more reliable than a color name, because “frosted,” “translucent,” and “mirror” are not single factory grades.
What the four finishes mean
Sheet standards such as ASTM D4802 sort acrylic mainly by light transmission class: clear, translucent, and opaque. Mirror and frosted finishes are commercial surface or body treatments inside that broader scheme. A buyer should specify both the polymer and the finish, for example “cast PMMA, one-side matte, 3 mm.”
Clear
Clear acrylic is polished on both faces and formulated for high visible-light transmission. Optical-grade cast sheet is the usual choice when a product, photo, or QR code sits behind the panel. Transmission falls as thickness increases, and a tinted “clear” sheet is not the same as colorless sheet. Edge polish also changes the look: a flame-polished or diamond-polished edge stays bright; a saw-cut edge looks milky.
Frosted
Frosted acrylic scatters light at the surface. Factories make it by casting a matte face, sanding or bead-blasting a polished sheet, or applying a frost film. A one-side frost keeps the reverse printable and easier to clean. Two-side frost hides fingerprints better but is harder to wipe and can lower contrast for rear printing. Frost is a privacy and glare treatment, not a structural upgrade.
Mirror
Mirror acrylic is usually a clear or tinted sheet with a reflective coating on the back, then a protective paint layer. The coated face is the back. Cutting, drilling, and heat bending can mark or crack that coating near the edge, so the process route matters more than it does for plain clear sheet. First-surface mirrors exist, but most display parts use a back-coated sheet so the acrylic face can be cleaned.
Translucent
Translucent acrylic lets light through while blocking a sharp image. Color is usually in the body of the sheet, not only on the surface, so a cut edge shows the same hue. It is the practical choice for colored blocks, light boxes, and backlit logos. “Translucent white” and “frosted clear” can look similar in a photo and behave differently under a point light source. White translucent sheet is the usual diffuser; frosted clear is the usual privacy panel.
Comparison table
Values below are selection guidance, not a test report. Published light-transmission figures depend on grade, thickness, measurement method, and whether the finish is in the body or only on one face. Ask the sheet supplier for the grade data sheet before treating any percentage as a specification.
| Finish | What a viewer sees | Best primary job | Watch-outs |
|---|---|---|---|
| Clear | Object or insert behind the sheet | Product risers, photo blocks, menu sleeves, QR panels | Shows scratches, dust, and glare; edge quality is obvious |
| Frosted | Soft light, blurred shapes | Privacy screens, glare control, matte sign faces | Fine text behind the sheet loses contrast; matte face marks more easily |
| Mirror | Reflection of the room | Cosmetic displays, feature panels, concealed backs | Coating is sensitive at cut edges; not a see-through panel |
| Translucent | Color, glow, no sharp image | Colored blocks, backlit logos, light-diffusing panels | Dark colors can look opaque in thicker sections |
When to use each finish
Clear: readability first
Choose clear when a person must read through the material. That includes a card in a sign holder, a brochure in a pocket, a product on a riser, and a QR code printed on the back of a panel. For a counter QR sign, colorless sheet in the 2–5 mm range is the usual starting point: thick enough to stand, thin enough that the code stays sharp. Print the code on the back, or keep a front-printed code away from a high-wear edge.
Clear is also the default for solid brand blocks when the design is engraved or the block is meant to look like glass. If the block will be handled often, specify an edge finish and a scratch-care note. Acrylic is softer than glass; a polish does not stop wear.
Frosted: glare and partial privacy
Choose frosted when the sheet should soften reflections or hide a cluttered background, and when the message is printed on the sheet rather than read through it. A frosted face in front of a window sign reduces mirror-like glare. It is a weak choice in front of a small QR code or a paragraph of body text, because scatter lowers contrast.
For a reception screen or a price-list cover, one-side frost with printing on the smooth face is easier to produce and clean than two-side frost. Confirm which face is matte on the sample. Reversing it changes both the print surface and the look of fingerprints.
Mirror: reflection, not a window
Choose mirror acrylic when the panel should bounce light and conceal the wall, shelf, or hardware behind it. Cosmetic trays, jewelry back panels, and feature plinths are typical. Do not use it where a guest must see a product or a code through the sheet. If a logo is required, print or engrave the front face, and keep holes and notches away from the viewing area so coating creep at the cut is less visible.
Mirror sheet is a poor outdoor default unless the coating system is specified for that exposure. Humidity at an unprotected cut edge is a common failure point. For indoor retail, a painted backing and sealed edges are the practical controls.
Translucent: color that still carries light
Choose translucent sheet or block color when the part should read as a color from across the room and still glow if it is backlit or edge-lit. Colored logo blocks, pedestal stands, and light-box faces fall here. Thicker sections look darker. A 20 mm translucent red block will not match a 3 mm swatch of the same color code, even from the same supplier family.
For edge-lit signs, colorless or lightly tinted sheet usually carries light farther than a dense color. For a solid gift block that should look colored even with the light off, body-tinted translucent or opaque sheet is the more predictable route.
Thickness, edges, and printing
Finish and thickness should be chosen together. A 3 mm clear panel in a table tent is stiff enough for many counter uses. A freestanding block often starts around 10 mm and goes thicker when it must feel substantial or hold an engraved image. These are ordering ranges, not load ratings.
- Cast sheet is the common choice for thick blocks, machined edges, and laser engraving. Extruded sheet is common for thinner formed parts. They can both be clear; they do not machine or cement identically.
- UV printing suits full-color graphics on clear, frosted, and translucent faces. Leave a small unprinted margin at edges that will be polished after printing.
- Laser engraving shows well on clear and lightly tinted material. On dense translucent colors the mark can lose contrast.
- Solvent cement joints are clearest on clear-to-clear bonds. A frost face or a mirror backing should not sit in the joint.
Common mismatches
- Frosted sheet in front of a payment QR code. Use clear, or print the code on the frosted panel at a size that still scans.
- Mirror acrylic ordered as a “see-through luxury” menu holder. The coating blocks the view.
- A thin color chip approved for a thick block. Approve the color in the production thickness.
- Two-side frost specified, then a photo-quality reverse print requested. Use one-side frost or print on a separate clear insert.
Who Custom-display.com is
The finish guidance above is general acrylic practice. It is not a claim that one factory’s sheet outperforms another.
Custom-display.com is the product site of Sunday Knight Co., Ltd., a Dongguan acrylic manufacturer operating since 2012. The site sells wholesale custom parts, including acrylic blocks, sign holders, brochure holders, and cut-to-drawing parts. A counter example is the acrylic QR code sign holder, which is normally specified in clear or colored sheet. Company background is on the about page.
For a finish decision, the useful factory inputs are sheet grade, thickness, which face is frosted or coated, edge process, and a sample under the real light. Color names alone are not a specification.
FAQ
Is frosted acrylic the same as translucent acrylic?
No. Frost is usually a scattering surface on otherwise clear sheet. Translucent usually means color or diffusion through the body of the sheet. They can look alike in flat light and differ under a lamp or at a cut edge.
Which finish is best for a QR code?
Colorless clear acrylic, with the code large enough and the surface free of heavy texture. Frost and dense translucent colors reduce contrast. Mirror sheet hides a code placed behind it.
Can mirror acrylic be cut after the coating is applied?
Yes, but the cut edge needs a process that limits chipping and coating damage. Specify edge sealing if the part will be cleaned often or placed in a humid area.
Does a thicker clear sheet stay as clear?
It stays transparent, but transmitted light and any tint become more noticeable as thickness increases. Approve thick blocks with a sample, not with a thin offcut.
What should a purchase order name?
Polymer, cast or extruded if it matters, thickness, finish and which face, color in that thickness, edge finish, print or engraving method, and quantity. “Premium clear” is not a grade.
Sources
- ASTM D4802, Standard Specification for Poly(Methyl Methacrylate) Acrylic Plastic Sheet. Classification includes clear, translucent, and opaque transmission classes. astm.org/d4802-16.html
- ISO 7823-1, Plastics — Poly(methyl methacrylate) sheets — Types, dimensions and characteristics — Part 1: Cast sheets. iso.org/standard/73714.html
