Re: paper
rdalrymple (dalrymple@hidesert.com)
Wed, 28 Aug 1996 08:29:35 -0700
Bas van Velzen wrote:
>
> Judy wrote:
>
> But now that you bring the subject up, I think the list would be very
> interested next in learning some of the plusses and minuses of the 3
> different types of paper. (Anyway, I would.)
>
> On Tue, 27 Aug 1996, Bas van Velzen wrote:
> > mono-layer: tear the paper cross grain- no layers will become visible
> > multi-layer couched:tear in same way- layers will be visible (up to three)
> > multi-layer glued: burn corner of paper- layers will be visible (as ash)
> > and will have separated, fanned out -couched papers will not show separated
> > layers after burning-
>
> As you will remember I always had hesitations with multi-layered
> objects. Especially when they are supposedly single property items (such as
> CD's, photos etc.) The fact that they have more than one layer means that
> the layers interact with each other. This goes for paper too! Here I am
> talking about machine made paper, handmade paper has all the described
> properties but not so prominent and often hardly distinguishable.
> Couched paper is most times made pressing the felt sides* of two
> paper rolls of two paper machines together when the paper is just made (the
> water content of the paper will be between 10 and 8%) in this way the paper
> fibers can still intertwine a little and establish a bond. This is done to
> give the paper the same (printing) characteristics on both sides. On
> wetting such sheets in a water bath air bubbles can form between the two
> layers. The bond between the layers is not so strong as to prevent this.
> When two different papers are couched together the paper will have more
> problems since the layers will act differently on wetting. The paper will
> be fairly easy to flatten after wetting.
> Glued papers are more stiff than couched papers and since this bond
> is most times stronger air bubbles will not easily form on wetting. Glued
> papers will have more problems in lying flat when dry because the glues
> contain water. The paper rolls being glued together will swell on one side
> and develop stresses on drying. The papermaker will try to avoid these
> stresses by carefully conditioning the paper before and after glueing.
> Glued papers can also be made using sheets. These will have the machine
> directions changed with each layer thus more or less eliminating stresses.
> Wetting glued papers in a water bath will release the stresses in the
> paper, it will be very difficult to flatten the paper afterwards.
> In general mono layer papers are the most easy to control, although
> the two sides are slightly different the overall stresses are lesser in
> these papers. The heavier the paper can be made in one layer the less these
> differences will be noticeable. A heavy paper will be about 180 grs/m2.
> Above this weight it will soon be called carton and above about 400 grs
> board. Cartons and board will almost always have more than one layer.
> Handmade papers, when well made, will have less stresses, less
> direction and less differences between sieve and felt side. Also a fresh
> made paper will be more difficult to control than matured paper, the drying
> stresses are still present in the paper. Remember that in machine made
> papers the fibers are totally saturated with water when poured on the sieve
> and then dried in a matter of minutes to 3% water content. This stresses
> the fibers very much. When I buy paper I will keep it for over a year to
> mature it. Keep your paper well protected from light and dust and keep it
> flat. In cases where the paper is not flat keep it under just enough weight
> to have it flat. After some time you will see the paper will keep flat even
> after taking away the board and weight. Heavy cockled papers cannot be
> flattened when the air is dry (under 40% RH), wait for the wetter season.
> For those who have the time and energy to read a little more on this
> subject:
>
> Hunter, Dard
> Papermaking, the history and technique of an ancient craft
> New York 1947, 19?? - Dover publications
> ISBN 0-486-23619-6
>
> Heller, Jules
> Papermaking, the white art
> New York 1978 - Watson-Guptill publications
> ISBN 0-8230-3895-5
>
> Saltman, David
> Paper basics: forestry, manufacture, selection, purchasing, mathematics and
> metrics, recycling
> New York 1978, 1991 - Krieger publishing company, Malabar, Florida
> ISBN 0-89464-569-2
>
> Turner, Silvie
> Which? paper
> New York 1994 - Lyons & Burford
> ISBN 1-55821-312-0
>
> * paper has two sides: the sieve side where the paper lies on the sieve
> when being formed contains more smaller fibres. This means that when wetted
> the sieve side will swell more and is bigger in this situation. The sieve
> side can be recognized in raking light: look for a sieve structure. Also in
> coloured papers the sieve side is darker: pigments will sink in the paper
> due to gravity and dyes will adhere more easily to the short and relative
> broad fibers.
> The felt side is pressed together with the couching roll (which is
> made of felt) and is therefore more compressed and smoother. Sometimes a
> structure is pressed in the paper on this side with a dandy roll. Also
> (false) watermarks are made this way.
>
> Jonge Eland papierrestauratie
> eland@knoware.nl
> t +31 20 623 79 89
> f +31 20 627 32 23
>
> VeRes (Dutch Association of Professional Restorers)
> postbus 11503
> 1001 GM Amsterdam
>
> PAPER IS ART IS PAPER IS ART IS PAPER IS ART IS PAPER IS ART IS PAPER
As a beginner on this listserve, I have some beginner's questions.
Would anyone besides myself be interested in starting a thread about
negatives for cyanotype and gum prints? I would like to know which is
best, more common or favored-multiple negatives, continuous tone, high
contrast, low contrast? Do any of you use negatives and positives (for
the same final print) for your printing? I would appreciate any comments
on this subject. Also, what types of film and developers are favored
for the final negatives and are slides or negatives (black and white or
color) most often used by most of you?
Looking forward to your comments,
Marilyn
(As a beginner on this listserve I have not had any luck just sending a
message. I seem to have to "reply" and tag my messages on to others
that are not always written about the subject I want to discuss. Excuse
my interuptions--I am trying to learn how to do this properly.
M