into the Properties of Porcelain Paperclay
by Gaye Stevens
Originally published in Ceramics
Technical. Reprinted by permission.
In July, 2000, I began a research project
with the assistance of a Faculty Research Grant from The College
of Fine Arts,University of New South Wales to investigate the properties
and potential of porcelain paperclay.
My studio work is concerned with the vulnerability
of being human, with the dynamics of how we interact as a community
and the consequent processes of acceptance and rejection. Hence,
the juxtaposition of light and shadow has held significance for
me as a metaphor for inclusion and exclusion. I have been searching
for a medium that will convey fragility and vulnerability but one
that also has a degree of permanence. In early 2000 I had read an
article by Steve Harrison ‘The making of paperclay porcelain banners’
(Pottery in Australia 37/2 1998 p68-69). In this article, Harrison
describes how he makes paper-thin porcelain banners of translucency
that can be imprinted with "tools fingers and objects".
It seemed that this medium had potential for the type
of sculpture I wanted to produce. My aims were twofold. Firstly,
I wanted to find a way of imprinting thin sheets of this body with
a photographic image to produce a watermarked effect. That is, I
wanted to find a way (without using any ink), of pressing a photographic
image into the clay body, using some appropriate kind of intaglio
printing plate, in order to yield a heavily embossed image which
when backlit, would produce a photographic watermark. Secondly,
I wanted to explore the potential of this body for producing 3D
forms that would lend themselves to illumination.
My starting point was his recipe for porcelain paperclay
- Clay Ceram 50 %
- Nepheline Syenite 50%
- Ceramic fibre (1000˚C) 8 %
- Fine paper pulp 17 %
- Water 30%
The clay body is fired to cone 8 in an electric kiln.
The ceramic fibre helps to stabilize the body after
the paper pulp has burnt out at 250ºC and stops the thin sheets
from cracking "along the stress lines created by the decoration".
The initial process of familiarizing myself with porcelain
paperclay body proved to be not as straightforward as I anticipated.
The result of my first batch was coarse textured and short, totally
inappropriate for holding the imprint of a recognizable photographic
produce a finer textured body I used shredded ceramic fibre (rather
than ceramic blanket which I had used initially, that had to be
laboriously torn into tiny pieces) and mixed it with a heavy-duty
blunger in about four liters of water, until satisfied with its
homogeneous consistency. I mixed the paper pulp in a similar way
and with about the same amount of water, but I used boiling water
this time, to help break down the fibres. The ceramic fibre and
paper pulp were then thoroughly mixed with the blunger and the other
dry ingredients were added.
The extra water in the mix, which allowed for easier
blending, was removed by heaping the clay on a plastic tarpaulin
and allowing the clear water to run off over a few days. The resultant
body was sticky. I found the easiest way to work with it was to
roll it into slabs between sheets of heavy-duty plastic.
Initial trials of imprinting the porcelain body with
ceramic stamps were effective. The clay held the imprint crisply
and I was encouraged to think that a photographic image would be
possible if the right type of ‘stamp’ (plate) could be found. I
had used solar etching plates to produce photographic etchings in
printmaking and thought it might be possible to use such a plate
to imprint the clay. Unfortunately, the solar plate was unsuitable
for this process because the light sensitive emulsion on the plate
was unable to maintain the sustained contact with the clay body
necessary to imprint it. The emulsion absorbed moisture from the
clay body, expanded and separated from the backing plate. The resilience
of the high cellulose content in the body also prevented it from
being able to hold the fine imprint to any degree that would produce
an effective image.
In a photographic exhibition of work by Jenny Pollack
and Louis Vidal, entitled ‘Passages’, (Customs House Sydney, November
2000) I saw embossed photocopies of photographs that had been produced
to make a tactile, readable surface for people with impaired vision.
These photocopies are produced with a special heat-sensitive paper
which when passed through a PIAF machine reacts to raise the areas
printed with ink to give a kind of Braille photocopy. With the help
of Michael Keighery at the University of Western Sydney, Milperra,
I was able to produce a photographic 3D image. By using a printing
press, I imprinted this image into a standard clay body and the
imprint was sharp and readable. When I repeated the process with
the porcelain paperclay the resilience of the cellulose once again
reduced the clarity of the image. I discovered that by allowing
the paperclay mix to age (at least one month), this resilience was
reduced and the readability of the image improved, but the results
read more as a silhouette than a photographic image.
An article in Ceramic Review May/June 2001 presented
research by Helen Smith at the University of the West of England
on the potential of using flexography to emboss paperclay with a
Further inquires within the printing industry led
me to a du Pont product named Cyrel®. This proved to be just
what I was searching for. Cyrel® is a flexible vinyl plate of
approximately 10 mm thickness to which a photographic image can
be transferred by placing a photographic transparency on the plate
and exposing it to intense UV light. The process duplicates even
the minutest detail and the resulting stamp-like plate will effectively
imprint the porcelain paperclay.
I roll the clay to a similar thickness to the Cyrel
plate, spray the top of the slab with a fine mist of water and smooth
the surface with a plastic ruler. I then leave it to a dry leatherhard
state and use a rolling pin to imprint the clay with the plate.
By drying the imprinted slab slowly over a few days I avoid any
warping. The slab is then fired slowly on a flat even bed of white
silica sand in an electric kiln to cone 8.
The fired porcelain paperclay is porous and fragile.
As Steve Harrison suggests, it can be painted with acrylic medium
to give it strength and flexibility and the medium gives the surface
an almost imperceptible luster. Early results have been most encouraging,
to my mind opening up enormous possibilities for future development.
In my initial attempts to produce three-dimensional
forms, I experimented with various construction and firing techniques
and although the paperclay was effective at the construction stage,
immense care had to be taken during drying to avoid warping. I found
the most effective construction technique was to work with leather
hard or even totally dry slabs that had been cut to the desired
shape with a sharp blade and to join them with a slightly drier
than normal paper porcelain slip. It was also possible to roll partially
dried slabs into cylindrical forms. However, during firing, even
with meticulously built supports, the forms warped slightly and
although in some cases this was acceptable, it was too ‘organic’
for the type of form I wished to produce at this point.
For my purposes, I overcame this weakness by constructing
the forms after firing. In the first instance where I wanted to
convey a sense of precariousness and tension, and the fragility
of sanctuary, I layered the sheets to create the 3D form. In another
piece that addresses the effort that must go into the construction
of sanctuary, I perforated the edges of the sheets and sewed them
together. The results have been rewarding, to my mind embodying
all the fragility and vulnerability I had hoped to convey.
Porcelain paperclay while challenging traditional
methods of production, has presented possibilities for my studio
practice. The edges possible with this body, its translucency and
affinity for light, and its seeming fragility are qualities I intend
to investigate further.
Because of the health hazards associated with ceramic
fibre and dry paper pulp, it is essential to use a facemask and
gloves while mixing this body. Mix the clay in an area with sufficient
ventilation and when touching the ceramic fibre, cover as much of
your body as possible with protective clothing.
At the time of writing, Gaye Stevens
was a M Des(Hons) candidate at the College of Fine Arts, University
of New South Wales, Australia. Supervisor: Jacqueline Clayton.
How to make Paperclay
More on Paperclay - article by Graham Hay
Paperclay - Links