Re: Rives BFK, again

Keith Schreiber (KEITH@ccp.arizona.edu)
Wed, 17 Jan 1996 19:02:39 -0700 (MST)

Carson Graves wrote:
> I'm sure they haven't changed their formula in 200 years, but rags
> sure have changed their content in that time. From the early 70's
> to the early 80's I started noticing spots of polyester "contamination"
> in art papers (including BFK, which I have used more than any other
> paper). These were translucent, fused "goobers" (nice scientific term)
> which were easy to spot by holding up the paper to light.
>
> I don't know if paper manufacturers have gotten better about getting
> the double-knits out of their rag supply lately or not as I haven't
> looked at that much of it lately.

In the paper tests I am working on for pt/pd, I have found several
papers in which it appears that some of the fibers do not absorb any
of the coating material. These polyester "goobers" would seem to be a
likely culprit.

I did the densitometer readings yesterday for about 2 dozen or so
step wedge tests. Things are a bit crazy here with an exhibition
opening Friday that we are busy installing so I will have to delay
until next week reporting those results. Also I will plot the curves
though I don't know how to put that on email.

Keith
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Keith Schreiber
Center for Creative Photography
University of Arizona
Tucson, Arizona 85721
520-621-7968
520-621-9444 FAX
keith@ccp.arizona.edu