trying the paper negative idea
Please elaborate; do you mean you intend to print digital files using an inkjet printer onto paper, and then use those paper prints as negatives that you want to contact print using a wet process?
I never tried this, but in principle it should work. I think your best bet is to not use a paper for the negatives but instead just use generic screen printing transparency film. This is similar stuff to the far more expensive Pictorico OHP and Fixxons, and indeed, with somewhat modest ink loads behaves nearly identically to Fixxons in my experience. This way you don't have to worry about the influence of the paper base, although a thin (low-cost) inkjet paper might work just as well, as these tend to pass quite a bit of light. How much light you need, will depend on the final printing process. Since it's unspecified, I can't comment.
To get decent prints, you'll need to make the final prints 'emulsion to emulsion', so have the inkjet-printed negative image in direct contact with the final printing medium (e.g. silver gelatin paper). You'll also have to go through the process of linearization, as the inkjet negatives as they print 'out of the box' will give very wonky curves due to the sensitivity characteristics of the final printing medium combined with the idiosyncrasies of inkjet prints (dot gain/bleeding, light transmission etc.) There are several methods for linearization, ranging wildly in the software and hardware they rely on. If you dig around a bit online you'll find solutions like Peter Mrhar's Easy Digital Negatives, linearization using QuadTone Rip (for Epson printers) or a variety of plugins relying on scanner captures mostly for Photoshop.
