TNF - thermal negative film

Jewelry Discussion
1

I’m in the process of producing photopolymer plates from reduced
images of my ink paintings. In order to get a good solid black and
clear negative, I’m using Thermal Negative Film (TNF). Has anyone
here worked with this product? It uses a developer that is sprayed on
after the film has been exposed. I’m wondering what the developer
chemical is, and if it might be able to find it locally. I’m running
through the small amount that came with my kit fairly quickly.

Pam East

2

You can also use a good quality copy machine with clear acitate and
it will do the job! Used this process MANY times for a jewelry
manufacturer for 12 yrs. and works fine. Also cheap!

Steve

3

Hi Steve,

That is exactly how I’ve been doing it for the past year or so, and
it’s worked fine as long as my designs were bold enough. But lately
I’ve started working with more detailed images containing a fair bit
of very fine lines, and I started having a problem with it. The black
on the photocopier image just isn’t black enough to allow for a
longer exposure time on the PPP and the fine lines would lift off
during the scrub out phase. The black on the TNF is so dense I can
double my exposure time on the PPP. I’m now getting very crisp,
sturdy results, including the very fine lines.

It’s possible I didn’t have access to a good enough quality copy
machine. I tried at Kinkos and Staples several times and was never
able to get anything darker than I could get on my laser printer at
home. I made one poor tech redo the transparency about 6 times before
I gave up. Lol.

Pam East

4

The clear acetate is called “overhead transparency film”. It is
designed specially for photocopiers and transfers the toner onto the
film.

5 
it's worked fine as long as my designs were bold enough. But
lately I've started working with more detailed images containing a
fair bit of very fine lines, and I started having a problem with
it.

You can always try touch up with a black sharpie.

6

Fast copiers, like those at Kinkos and Staples are built for speed.
If you search for an old used Canon photocopier, this will work
great.

I found one on Craig’s List for $100. The toner will actually cost
you as much or more than the printer, but it will last for a long
time. The slower the movement, the more toner gets slathered on, the
better the resist.

k
Karen Christians
Waltham, MA
http://www.cleverwerx.com

7 
Fast copiers, like those at Kinkos and Staples are built for
speed. If you search for an old used Canon photocopier, this will
work great.

I didn’t realize how much I had lucked out! I have an ancient Cannon
I bought at an estate sale for maybe $30. I can barely lift it (and
I’m not dainty) but it works great for transfering images to acetate
for etching.

The reason I mention this, other than to make you jealous, is that I
got a new toner cartridge for it on eBay for a fraction of what it
costs at the regular stores.

Noel

8 
You can always try touch up with a black sharpie.

Touchup is very common practice. Most offset negatives, for example,
are examined and touched up on a light table before they’re used to
burn plates.

It’s simple to do – provided you’ve got a big enough light table.

RC

9

The clear acetate is called “overhead transparency film”. It is
designed specially for photocopiers and transfers the toner onto the
film.

k