Definition
File Requirements for UV direct-to-object printing. Send a vector file when possible (PDF, AI, EPS, SVG). For raster art, send a 300 DPI file with a transparent background at the final print size. RGB color, no white background layer, and the white underbase will be generated for you.
File prep is where most projects pick up time. The fixes are not complicated, but they need to be done before submission, not after the proof comes back wrong. Most UV print jobs print from either a vector file or a 300 DPI raster with a clean alpha channel. Get those two right and most other issues disappear.
Submission checklist
- Vector file (PDF, AI, EPS, SVG) preferred. Send raster only when the art is photographic.
- Raster files are 300 DPI at the final print size, not scaled up from a small original.
- Background is transparent for raster files. No white box around the artwork.
- Color mode is RGB with sRGB profile embedded. CMYK files convert on intake.
- All text in raster files is converted to outlines or rasterized.
- All effects, smart filters, and adjustment layers in PSD files are flattened.
- Hairline strokes are 1 pt or thicker at final print size.
- Smallest text is 6 pt or larger.
- File is named clearly: jobname_size_v01.png. No spaces.
Specs reference
| Spec | Value | Notes |
|---|---|---|
| Preferred format | Vector (PDF, AI, EPS, SVG) | Vectors scale cleanly, give the sharpest edges, and rip fast. |
| Accepted raster | PNG, TIFF, JPG | Transparent PNG preferred when the design has a clean cutout. |
| Resolution | 300 DPI at final print size | Lower resolution causes edge pixelation and banding on solid fills. |
| Color profile | RGB (sRGB) | Our print engine renders in extended RGB with a white channel. CMYK files convert on intake. |
| Color mode | RGB 8-bit | 16-bit and 32-bit files are flattened to 8-bit before RIP. |
| Background | Transparent for raster, no background for vector | Save flat color or transparent. A hidden white background layer creates a halo. |
| White channel | Auto-generated from alpha | Submit a clean cutout. The RIP builds the white underbase for you. |
| Minimum stroke | 1 pt at final print size | Hairlines below 1 pt may not lay down a clean white underbase. |
| Minimum text height | 6 pt | Below 6 pt fine details get hard to read once the color layer prints. |
| Bleed | None required | UV prints land exactly where the artwork lives. No trim margin needed. |
| Layer flattening | Required for raster, optional for vector | Live text in vector is fine. Flatten PSD effects and smart objects before sending. |
The white channel
UV printing uses a separate white ink channel that lays down a base layer before the CMYK color hits the substrate. On dark wood, black acrylic, clear glass, or any non-white surface, the white underbase is what lets your colors pop instead of getting absorbed by the surface color. Our RIP software generates the white channel automatically from the alpha channel in your file. You do not need to create a custom white plate.
If you want a partial knockout (for example, an area where the substrate color should show through on purpose) include that as a separate file or as a clearly labeled layer in your vector. We will preserve it in the white plate.
RGB versus CMYK
UV print engines work in an extended RGB color space with the added white channel. We accept CMYK files but convert them to RGB on intake. If exact color match is critical, send a Pantone reference number or a physical sample and we will tune the file to match. Pantone colors do not translate one-to-one to CMYK or RGB. The conversion is always approximate without a printed proof to compare against.
Soft edges and transparency
Soft edges, drop shadows, and feathered halos reproduce cleanly because the RIP reads the alpha channel directly and applies a matching gradient to the white underbase. The shadow lifts off the substrate with the same softness it has in your file. The common mistake is exporting from Photoshop with a hidden white background layer turned on, which produces a hard white halo around the entire design. Always preview the file against a transparency grid before submitting.