how to merge a paste with 100% of opacity?

[Barabba]

Hi, thanks for support, the example will give you a better idea than explanation.
Imagine you have a word document printed on jpg, you woud add on it a stamp (blue color) to make the document official as really printed and stamped and after scanned.
At this moment I can paste the stamp ad a transpaernt layer over the document, but the blue ink of the stamp cover completely the black text around, the result is obviously a fake. Giving it a bit of transpaerncy make the result more acceptable, but the ink becomes more light (going to white) and the black of the text isn't that black.. as would appear if I scan the real stamped document..
ON the opposite, reducing the document text opacity make the black text "not that black".. looks a fake too.
How can I merge keeping both on thr 100% of opacity? Thank you

[Jean-Luc]

Could you complete your Profile with the version of PSP you use?

Concerning your problem, you need to work with layer and Blend mode. The Mode Multiply could perhaps do the job.