CMYK Black

[Luciano]

Turan,
I suggest that you use pure 100% k for text without CMY.
Text should be set to "overprinting", (right click imagesetting)
Do not forget to put text above pictures not behind (even for transparent ones), if you want to avoid finding text converted to a bitmap.

See attached example and the pdf output (PDFx1/a).
If you can check the pdf file you will verify it is pure black covering the picture behind, leaving no "holes" in it