DIP Online
Designs Ink
Publishing Article Archive and Reference Library
Articles
by Chris A. Paschke, CPF GCF CMG
"Abridged History of Dry
Mounting "
October 2004
I recently encountered a
short written history of dry mounting and noticed an interesting parallel
between the history of handling photographs and that of digital prints and fine
art of today. In order to better compare them let’s take a look at an
abbreviated history of dry mounting in general.
ABRIDGED HISTORY OF MOUNTING
Whether for holding things
together or for repairing little accidents of time and misfortune, there has always
been a need for adhesives. From the early 1800s to 1945, adhesives included
protein based (hide glue, gelatin); sugar based (dextrin); starch based (arrowroot,
wheat, corn, potato, rice); vegetable or gum based (arabic…); rubber based
(rubber cement); and assorted combinations of these materials. Extensive
moisture was necessary when bonding any of the above adhesives which introduced
expansion, stretching, cockling and/or curvatures in both photographs or paper
prints. Rubber cement was least moisture
inducing, but contained sulfur that discolored and often failed shortly after
mounting.
In an effort to keep
moisture down, a thin paper carrier was developed with thermoplastic adhesive
on either side which was activated by heat. Dry mounting had arrived. The term
"dry mount" was originally used to distinguish between this new dry
technique from traditional damp and wet techniques of mounting. The first dry mount tissue patent was issued
by the “Derepas Brothers” in France in 1901. In 1903, a British Company called
the Adhesive Dry Mounting Company, Limited, received patent #17,327 "An Improved Process for Mounting
Photographs, Engravings, and the like, and as a Means for Carrying the same
into Practice." As stated by
the British company, they had developed a material capable of mounting
“…photographs, engravings, or documents of any kind, on Bristol board or
cardboard...”.
The Kodak Company started
manufacturing dry mount tissue with what might have been the Derepas formula in
1906. And by 1915 the self proclaimed
“pioneers and originators of dry mounting” the Adhesive Dry Mounting Company,
Limited adopted the anagram ADEMCO for their company.
EARLY TTPM
The new adhesives used thin
silk paper or Japanese paper as a carrier which was dipped into an alcoholic
solution of shellac then dried. In 1907, recommended temperature tolerances for
photograph mounting were published in The
Photographic Monthly as follows:
|
Carbon and gum prints |
140-150°F |
60-65°C |
|
Gelatine-chlorides
(strongly alumed) |
165-175°F |
75-80°C |
|
Albumen |
195°F |
90°C |
|
Platinum, plain-salted
silver, and prints with matt faces no
gelatine |
95-205°F |
90-95°C |
With very thick papers it
was stated, “…these temperature may be increased a little and the time could be
lengthened to 15-20 seconds for bonding.”
This is the first indicator of time, temperature, pressure, moisture
rules (TTPM). Interesting that even with the later development of more heat
tolerant resin-coated (RC) photos, suggested mounting temperatures have
remained very similar even today. Note
the lower temperatures suggested for carbon prints at 140-150°F, partnered with
the short dwell time of less than 15 seconds. Sounds like the low temperature, short dwell
time HA boards (SpeedMount™…) that have been developed for heat sensitive
digitals today.
The same article goes on to
say, “…To remove a mounting, heat a metal plate to 250°F or 300°F (120-150°C)
and lay the print upon it, raise the corner and the whole print can be stripped
without injury.” The warmth of the
highly heated metal plate beneath would penetrate the photo from behind without
risking surface damage while still reactivating the adhesive for removal.
EARLY EQUIPMENT
Presses and irons were also
developed to accommodate the new techniques and materials. The first commercial
dry mount presses were advertised in 1904, and by 1906, advertisements for
tacking irons, called touchers or fixing irons, began as part of the
"Adhero" Dry Mounting Machine system sold by the Adhesive Dry
Mounting Company.
Machines introduced in 1906
were pressure controlled by a central screw and wheel system similar to letter
and book presses or clamp or lever models. These machines were initially heated
by burning paraffin, oil, gas, or alcohol,
but in 1907 were adapted for use with electricity. New innovation at the time, electricity. The
style and design of these early presses varies little from current hardbed and
softbed (mechanical press) models. Seal Products, Incorporated, founded in
Connecticut, 1936, developed their first dry mount mechanical press in 1947. Heated
vacuum presses did not emerge until the 1970s.
PHOTOGRAPHS AND ADHESIVES
Dry mounting is
historically the mounting process of choice by photographers for photographs. The
photographic industry standard has always been to develop materials and
processes to shorten working times, often implementing higher bonding
temperatures. Then, "in August 1934 Kodak introduced an improved [Type-I
tissue] with better adhesion and requiring less heat" (Wilhelm 1993). Lower temperatures again being potentially
less damaging to surface emulsions.
In 1941, a Kodak Chemical
Plant employee, Mr. Wentworth C. Eaton, cited most dry mounts as being
comprised of rubber-wax (cohesive tissues) or shellac (thermoplastic resin). Photos
using a faster developing process and waterproofed print papers might melt at the
higher 175-210°F temperatures required for mounting with shellac-based dry
mount tissues. In that same year, Kodak
released a lower 150°F temperature mounting tissue using a wax adhesive called,
Thermount Tissue which was marketed until 1957. Kodak continued to make Type-I
shellac-based dry mount tissue until February 1974 when it introduced Type-II,
a synthetic adhesive.
Seal Products released
their first dry mount adhesive, Foto-Flat in 1938. Specifically designed to target the lower
temperature requirements of photographs it was a synthetic, removeable tissue
that was impervious to moisture and unaffected by climatic temperature changes.
LOW TEMPERATURES CONTINUE
History continued and time
marched on. Numerous dry mount products have been developed by many companies.
From 1938 to date we have seen tissues come and go; companies fuse; and
formulations change lowering tissue bonding temperatures. Then came heat
activated boards, very innovative in the early 90s. Though p-s coated boards
and materials had been around, this was the first time a dry mount adhesive was
preapplied directly to the mounting substrate. They were clean, easy to use,
priced right, and huge time savers that were marketed for use "with
posters, paper artwork, photographs, newsprint and fabrics".
Not unlike many traditional
photographs, heat sensitivities have once again emerged issue with the
technologies of today. For home/office
inkjet printers that use thermal bubble jet technologies (most HP printers),
low bonding temperatures are a must. The demand for lower temperature adhesives
has been met over and over again with products bonding between 150-175°F, including Single Step Plus and SpeedMount. Even
with the above mentioned HA boards, as the mounting challenges changed from
traditional RC photo to digital photo to paper based art, so has the amount of
time the board must remain under heat and pressure to effectively activate and
bond. Remember the chart above printed
in 1907 for photo tolerances and the heat comments below it concerning
variables?
Most current HA boards
require from 15 seconds to 3 minutes to mount assorted items, with SpeedMount
suggesting the shortest dwell time. This is an important factor with Hewlett-Packard
printed digital photos or heat sensitive laser color images. Both images tolerate 150-155°F temperatures
for up to 30 seconds, but will often surface damage (even at that low
temperature) with a dwell time of 1 minute or more.
REMOVABLE OR REVERSIBLE?
As the industry
spokesperson for mounting, I have been the voice of framers to manufacturers
for almost twenty years now, always demanding more. During the 90s amidst the
onslaught of the early heat sensitive digitals and dropping adhesive
temperatures, my ongoing plea was for a pressure activated tissue adhesive
(not pressure sensitive or PSA) that could be bonded by only the pressure in a
cold frame, mechanical or heat vacuum press. They appear to still be working on
that one.
But, every now and then a
new mounting technique or product comes along that makes one sit up and take
notice. Something that didn’t fill any
specific void or request. Throughout history,
dry mounting as never been noted as a reversible technique, but at times merely
a removable one. And no dry mount adhesive could ever be totally removed. This is true because the very heat that
bonded the adhesive also encouraged absorption into the mounting, even when
removed there would always remain a limited amount of adhesive in the document
or artwork.
ARTCARE RESTORE™
So now we have been
introduced to Artcare Restore, and why is it different? By all accounts the
adhesive used with Restore is inert, pH neutral, and does not appear to leave
any adhesive residue once an image has been removed. All adhesive seems to
brush away. Adhesives notoriously will show up under a black light, like white
fuzzes. Yes even under a black light when removed there is no white remaining,
and any residue adhesive will dust off with your fingertips. Perhaps we simply need to trust the unknown.
Restore looks like any HA
precoated foam board though it does have a slight tooth to the matte finish
adhesive side. I have completed my own testing in relation to mounting and
removing images from photo to digital to newspaper, and have decided to believe
in this as a revolutionary new type of product, a new adhesive concept
altogether, not unlike the dry mounting of 1906.
THE ULTIMATE TEST
I am a purist when it comes
to framing my own artwork for my gallery. I only mat with 100% cotton museum
boards, UV Conservation glazing, and always use preservation hinging
techniques. As an artist for Wild Apple Graphics I have hundreds of originals,
some published, some stored. Since I
paint with sumi inks and collage many of my images, there are numerous variations
in paper weight, multiple layers and much moisture present during creation.
Hence the edges warp like watercolors can.
Hinging still may result in wavy edges beneath the window. Though I
consider this an intricate part of the creation it has never bothered me, but
clients would rather they not warp. Size all materials and prepare to mount.
Notice the completed double mat has already been completed. Tack the centered
artwork to hold it in place for mounting. Because of the thicker collaged
layers this image required 160°F for 1 minute to mount using release papers. The
completed image now shows smooth lines at the window edge.
DRY MOUNTING IN THE 21ST CENTURY
It has been established that
lower temperatures are safer for mounting. This is why the low temperature HA
boards have worked so well with photographs since their release. Adhesive
reformulations over the years have lowered tissue adhesive temperatures from
225°F to that of 190°F. Lower temperatures, less adhesive absorption, less
potential for damage. Yet, any adhesive absorption is not preservation. The
framing industry and conservators alike have had a tough time accepting new
practices. Dry mounting a traditional canvas is wrong, while dry mounting a
digital canvas is becoming the correct way to present it.
Throughout the history of
dry mounting, innovations in the formulations of dry mount adhesives have
evolved, first to meet the needs of photographic materials and technologies,
and now same with digital photographs, prints and canvases. Photography has dictated many new products
throughout the past 100 years.
In 1993, Stephanie Watkins,
AIC wrote “Dry mount has been used on photographs, books, papers, textiles, and
paintings in conservation treatments [throughout history], also. Therefore,
questions remain and the research continues.”
It is now 2004 and the research continues. Museum curators are being
forced to deal with large face mounted photos being placed in their
collections. This is the permanent
mounting of the surface of a digital print to the verso (back) side of clear
acrylic for display, generally by the artist. Museums now are buying one for
display, one for dark storage, times have changed. Remember the British company
that developed a material capable of mounting “…photographs, engravings, or documents of any kind, on
[acidic] Bristol board or cardboard...” at the opening of my article? They believed in gluing things down then.
We would never consider
using masking tape or corrugated cardboard to frame today, but we did at one
time. Perhaps a few years from now we will think back to the days we would
never consider dry mounting an original and think that sounds odd too. Now if I
can only get framers to see that mounting a digital canvas is also thinking
into the future we might be truly reaching into the 21st century of
framing.
Today my horse wears
plastic horseshoes; I send my articles via email attachment; and I mount some
of my original art with Artcare Restore, who knew? So get those wrinkles out of
that watercolor, and welcome to the 21st century!
END
Bibliography
“Origins
and Development of Dry Mounting”, paper by Stephanie Watkins, The American Institute for Conservation (AIC),1993.
MOUNTING, LAMINATING AND
TEXTURING, Seal Products, Incorporated, 1990
THE PERMANENCE AND CARE OF
COLOR PHOTOGRAPHY, Henry Wilhelm & Carol Brower, 1993.
Information on dry mounting
basics is found in The Mounting and
Laminating Handbook, Second Edition, 2002, and The
Mounting And Laminating Handbook, Third Edition, 2008. Creative Mounting, Wrapping, And Laminating,
2000 will teach you everything
you need to know about getting the most from your dry mount equipment and
materials as an innovative frame designer. All books are available from Designs Ink Publishing through this
website.
For live consultations with
Chris Paschke, CPF GCF call Designs Ink, 661.821.2188. A flat fee of $25 will
be charged for each new technical problem. Unlimited calls or emails are
allowed for each established mounting problem.
Chris A Paschke, CPF GCF
Designs Ink
Designs Ink Publishing
785 Tucker Road, Suite G-183
Tehachapi, CA 93561
661.821.2188