U of S | Mailing List Archive | alt-photo-process-l | Re: Palladium on vellum

Re: Palladium on vellum

Hi Loris

"Vegetable (paper) parchment is made by passing a waterleaf made of pulp
fibers into sulfuric acid. The sulfuric acid hydrolysises and solubilises
the main natural organic polymer present in the pulp wood fibers, the
cellulose. The paper web is then washed and neutralized in water, which
stops the hydrolysis of the cellulose and makes a kind of cellulose coating
onto the waterleaf. The final paper is dried. This coating is a natural
cement, non porous that gives to the vegetable parchment paper its grease
resistance which is the main feature of this paper along with its

Other processes can be used to obtain grease resistant paper, such as by
highly beating the fibers giving an even more translucent paper with the
same grease resistance. Silicone and other coatings may be applied to
parchment. One can obtain grease resistance by waxing the paper or by using
fluorine based chemicals. When a silicone coating treatment is applied to
the surface of the paper, this produces a cross-linked material with high
density, stability and heat resistance and low surface tension which imparts
good anti-stick or release properties. Chromium salts can also be used to
impart moderate anti-stick properties."

(from http://wapedia.mobi/en/Parchment?t=6.)

I have read somewhere else that the sulphuric acid process process actually
involves passing the paper through several acid baths, each weaker than the
one before it, then an alkali bath to neutralise the acid.  After that the
paper is washed and put through heated rollers.  It all sounds rather

Don Sweet

----- Original Message ----- 
From: "Loris Medici" <mail@loris.medici.name>
To: <alt-photo-process-l@usask.ca>
Sent: Monday, May 25, 2009 8:50 AM
Subject: Re: Palladium on vellum

> Very interesting Marek, congrats & thanks for sharing. I prefer the gold
> one -> suits the subject matter better IMHO. I also want to try that!
> That's if I manage to find such a transparent paper which is able to take
> wet processing (+ is chemically compatible with iron processes).
> I may try to process Masa paper (which is easier to work with than your
> vellum I presume) in sulfuric acid to make it more transparent -> if I'm
> not mistaking that's how they produce translucent / semi-transparent
> paper. Anyone with details about this?
> Regards,
> Loris.
> 24 Mayıs 2009, Pazar, 11:25 pm tarihinde, Marek Matusz yazmış:
> >
> >
> >  All,
> >
> >
> >
> > Finally after being inspired by Dan Burkholher's show I gothered all the
> > supplies and made my first palladium/platinum prints on vellum with
> > and gold leaf. This is one of my favorite prints that I printed many
> > in gum, so I include two versions of gum prints. The vellum that I am
> > using now is very translucent, but it crinckles and creases so easlily.
> > am learning how to deal with it. It did not really like being ironed
> > wet. You can see creases that are a result of that. On the other hand I
> > enjoying the wrinkles and hande-made feeling of the prints.
> >
> > My scanner broke down so these are photographs of the prints taken
> > with the sun positioned to acccent the vellum surface.
> >
> > Marek
> >
> >
> >
> >
> >
> > You have to copy and paste the link into your browser
> >
> >
> >
> > _________________________________________________________________
> > Insert movie times and more without leaving Hotmail®.
> >
> >