To export black text for black ink only, define it as CMYK C0 M0 Y0 K100, use a matching CMYK PDF export workflow, and inspect the exported separations. Affinity’s “Overprint black” setting does not convert every black-looking object to K-only black.

This guide covers editable text in the current Affinity desktop app on Mac, exported to a PDF for printing. The task is to keep that text on the process-black separation while allowing other artwork to remain in color. A PDF’s color definitions and a desktop printer’s eventual ink use are separate questions.

What does black ink only mean in the exported PDF?

For solid process-black text, the intended color definition is Cyan 0%, Magenta 0%, Yellow 0%, Black 100%, commonly written C0 M0 Y0 K100. Affinity describes CMYK black as an ink that can be used by itself or combined with the other inks to make rich black. The relevant distinction is the color’s components, rather than how dark it appears on your screen. Color models

A black-looking RGB color does not itself specify a black printing plate. RGB describes red, green, and blue light; CMYK describes printing components. Consequently, choosing an RGB black and later requesting CMYK output is a conversion workflow, rather than an explicit instruction to use only K. Affinity also warns that color values can change when converting between document formats or profiles. Color models

There are two useful acceptance criteria. First, the text object should have a K-only color definition. Second, its exported appearance should separate as intended. These criteria require special care when the text overlaps colored artwork: a K-only text object can overprint an existing colored background.

Set the document and text color before exporting

Establish the destination CMYK profile first

Ask the print provider which CMYK ICC profile and PDF specification the job requires. Affinity’s color-management documentation specifically recommends consulting the print partner for the appropriate CMYK profile. Using an arbitrary profile because its name appears in a tutorial leaves an essential output condition unresolved. Color management

For a new document, select the required Color format and Color profile during creation. For an existing document in the current desktop app, choose Document > Setup > Document Setup, open Color, and select the required format and profile. Affinity also documents Document > Setup > Convert Format / ICC Profile as a direct route. Choose CMYK for this workflow. Color models

Complete any necessary conversion before correcting the text’s numerical color. Affinity distinguishes Assign, which changes the profile while retaining values, from Convert, which recalculates values from the old profile to the new one. Assigning a different profile simply to retain numbers can change their intended interpretation. The practical sequence is therefore: establish the destination, convert if needed, then set the text. Color management

Apply an explicit K-only fill

Select the actual characters that need black-only output. If a text frame contains several colors, work with the intended text selection so that other formatting is preserved.

  1. Open Window > General > Color.
  2. Make the Fill selector active.
  3. In the panel’s preferences, choose Sliders and the CMYK color mode; use percentage values.
  4. Enter C 0%, M 0%, Y 0%, K 100%.
  5. If the text also has a stroke, check that separately and either remove it or give it the intended K-only definition.

Affinity documents the Color panel as the place to apply fill and stroke colors, select a color model, and use CMYK sliders. Entering all four values makes the intended ink recipe explicit. Avoid Shift-dragging while adjusting individual components: Affinity says that modifier moves all CMYK sliders together. Color panel

Repeat the check for every relevant text selection. A useful working checklist is body text, headings, captions, table text, and text on master pages. This is an editorial inspection sequence, not a claim that changing one selected object updates an entire document.

The same selection method cannot recolor letters that are already pixels inside an image. Treat such material as an image-editing task, or recreate the lettering as editable text before applying these steps.

Export the PDF without assuming the preset fixes black

Choose File > Export > Export. Affinity’s current dialog places presets on the left and settings on the right, with additional controls in Advanced. Select the required PDF preset, then inspect its settings. Also check Area: All Pages and All Spreads produce different page arrangements. Export dialog

The official preset comparison shows why the preset name alone is insufficient:

PDF preset Documented default color space What to check for this task
PDF (for print) As document The source document must already have the intended CMYK setup.
PDF (press ready) CMYK Confirm the profile and the provider’s required PDF compatibility.
PDF/X-1a:2003 CMYK Use when this is the requested delivery specification.
PDF/X-3:2003 or PDF/X-4 As document Confirm the document’s color space rather than assuming the preset forces CMYK.
PDF digital presets RGB These defaults do not match this CMYK delivery task.

These are Affinity’s documented defaults, and presets can be customized. Select the specification the recipient requires rather than choosing a PDF/X version solely because it sounds more suitable for print. Compare PDF export presets

For an already prepared CMYK document, check Color space is CMYK or As document, and keep Profile/ICC Profile aligned with the document’s intended output profile. Affinity exposes separate controls for export color space and profile; its documentation does not promise that an arbitrary profile change will preserve K-only text values. Export Settings

Leave Embed ICC profiles enabled when using the documented print preset defaults unless the recipient specifies otherwise. Disabling embedding is not a documented black-only conversion method: Affinity explains that an unprofiled export omits the profile information used to interpret colors. Compare PDF export presets, Color management

Avoid selecting Rasterize: Everything as a correction for text color. It turns the entire design into raster output. Unsupported properties limits rasterization to unsupported elements. Nothing has its own limitation: Affinity says unsupported elements are omitted, so it should not be selected indiscriminately. Export Settings

Click Export, give the file a name, choose its location, and click Save. Keep the editable Affinity document available for corrections after inspecting the result. Export dialog

Which export controls do not make text K-only?

Overprint black sets CMYK-black design elements to overprint. That documented contract does not say it converts RGB black or rich black into C0 M0 Y0 K100. Similarly, Convert image color spaces applies to placed images; it is not an editable-text black-preservation control. Export Settings

Affinity’s current export-settings reference does not document a dedicated command that remaps all black-looking text to process black during export. The supported preparation path is to define the text’s CMYK color explicitly, establish the appropriate output conditions, and verify the resulting PDF.

Overprinting also changes how you interpret a separation check. It prints an ink over the underlying color instead of removing that color beneath the object. Thus, black text over a cyan rectangle can have a K-only text fill while cyan still exists beneath the letters. Decide with the print provider whether overprinting or knockout is appropriate for that design. Glossary

Verify the exported PDF with a simple diagnostic test

Start with an illustrative test page containing only the neutral words Sample text 123, set to C0 M0 Y0 K100 on an unprinted white background. Export it using the intended production settings. This isolates the text from colored backgrounds and makes unexpected color components easier to investigate; it is a proposed test, not a reported measurement.

If you have Acrobat Pro, open the exported PDF and choose All tools > Use print production > Output preview. Choose Separations, use the intended output simulation profile, and inspect the text. Adobe documents controls for showing individual plates and reading ink percentages under the pointer. Preview the PDF output

On that isolated test, hide Black and leave Cyan, Magenta, and Yellow visible: the lettering should disappear. Show Black alone: the lettering should remain. Use Object Inspector to examine the object’s color mode as well. This combines a separation check with an object check rather than relying on a composite screen preview. Preview the PDF output

Then inspect the real production PDF. For text over colored backgrounds, use the object information alongside the separations because the background may legitimately remain on other plates. If you do not have a suitable PDF inspection tool, ask the print provider to check the exported text’s color definition and separations.

Use the result to choose the next action:

Observation Next action
Selected text has nonzero C, M, or Y in the source Reapply its fill, and inspect any stroke separately.
The isolated source test is K-only but exported text is not Recheck export color space, profile, and whether the text became raster content.
Only some text fails Inspect those text selections individually, including any placed content.
Color appears beneath black text over a colored shape Check overprinting and inspect the text object separately.
The PDF checks correctly but a desktop print uses color ink Investigate the downstream print workflow; the export check establishes the PDF’s contents.

Affinity’s own Preflight can help before export. Its documented checks include Text uses too rich black and, when the document expects only gray and spot colors, Text uses CMY. These checks depend on the active preflight profile and thresholds, so a green status is not a substitute for inspecting the exported PDF. Preflight

The practical finishing point is a PDF whose text color and separations meet the intended specification. Establish the CMYK destination first, apply explicit K-only text values, inspect the export settings, and check the exported file. That sequence gives you a concrete result to assess without relying on an undocumented black-conversion switch.

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