Fading of TTY paper

Peter D Verheyen <pdverhey [at] syr__edu> writes

>I have question regarding fading of yellow TTY (teletypewriter)
>paper from the late 1970s/early 80s. No doubt this paper was not
>intended to be retained permanently, however in this case the rolls
>are part of a landmark legal case and the donors would like to have
>them preserved. ...

I did a little bit of research on this topic a few years ago, but am
no expert. There were a number of different devices available for
teletyping. Typically the prints were made on endless paper, and the
typing mechanism could be either a daisy-wheel, individual keys, a
so-called golf ball, a cylinder, or a different mechanism. In all
cases it is a device with full characters that press an ink ribbon
against the surface of the paper, thereby transferring the ink. See
videos at

    <URL:http://www.pdp8.net/asr33/videos.shtml>

(take note of the yellow colour of the paper!).

Regarding the colour of the paper supports, there are some
interesting pictures of RTTY prints at

    <URL:http://bbsdocumentary.dreamhost.com/photos/099sheetz/>

While it is a little difficult to determine the real colour of the
papers from these photographs, since the photographer's camera's
white balance apparently had a will of its own, it is possible to
see within one of the photographs RTTY prints on different coloured
papers, some of which are whitish, some brownish, and some even
quite yellowish. Whether they originally had these colours or
whether this is due to paper deterioration I cannot say.

The printed characters are basically ink on paper, and the ink is
essentially a kind of typewriter ink. Some ribbons had more than one
colour, e.g. black and red inks. In Germany these ribbons were (and
still are) categorized by the DIN 2103 norm (DIN 2103: Office
machines; inked ribbons; woven fabric ribbons). See

    <URL:http://www.ro-fa.de/index.html?farbbaender.htm>

for some pictures of typical ribbons.

But consider that with a teletypewriter it was also possible to
create carbon copies (an option we have lost with contemporary
printers), since printing was based on impact. This means that the
papers you describe could be carbon copies and not the original
front sheets with the ink.

In general, I would recommend making a distinction between the
printed characters and the paper support, each of which could have
its own problems. I can't really see how the paper would "fade", as
you indicated in your query, although I can imagine it would yellow
if it is of poor quality. The printed characters, on the other hand,
could be fading, I suppose. I am sure a paper conservator
experienced with typewritten documents and carbon copies would have
sound advice for the preservation of these objects, and it would be
interesting to hear about this on the Cons DistList.

With all of this said, I must admit that I have not yet seen any
real RTTY prints with my own eyes, but perhaps the following
references will help you in your query:

    Rivlin, Robert. The Algorithmic Image: Graphic Visions of the
    Computer Age (Redmond, WA: Microsoft Press, 1986). pp. 14-15.

    Danet, Brenda. Cyberpl_at_Y: Communicating Online (Oxford; New
    York, NY: Berg, 2001). pp. 203-5

A very good resource for early teletype and computer printing is the
well illustrated book:

    Webster, Edward. Print Unchained: Fifty Years of Digital
    Printing. 1950-2000 and Beyond. A Saga of Invention and
    Enterprise (DRA of Vermont, Inc, 2000).

Finally, for ribbons and inks I recommend:

    Elbert, Donald L. et al.
    Ribbons and Inks, Output Hardcopy Devices, Robert C. Durbeck and
    Sol Sherr, eds. (San Diego: Academic Press, Inc, 1988). pp.
    413-439.

Martin Jurgens
Photograph Conservator, MA
Schumacherstr. 98
22767 Hamburg, Germany
+49 40 2800 4785
Mobile: +49 160 441 2563
Fax: +49 40 2805 6511


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                  Conservation DistList Instance 23:36
                  Distributed: Monday, March 22, 2010
                       Message Id: cdl-23-36-005
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