A spirit duplicator was a printing method invented in 1923 by Wilhelm
A spirit duplicator was a printing method invented in 1923 by Wilhelm

Ritzerfeld and commonly used for much of the rest of the 20th century. The term
Ritzerfeld and commonly used for much of the rest of the 20th century. The term

"spirit duplicator" refers to the alcohols which were a major component of
"spirit duplicator" refers to the alcohols which were a major component of

the solvents used as "inks" in these machines. The device coexisted alongside
the solvents used as "inks" in these machines. The device coexisted alongside

the mimeograph. Spirit duplicators were used mainly by
the mimeograph. Spirit duplicators were used mainly by

schools, churches, clubs, and other small organizations, such as in the
schools, churches, clubs, and other small organizations, such as in the

production of fanzines, because of the limited number of copies one could make
production of fanzines, because of the limited number of copies one could make

from an original, along with the low cost and correspondingly low quality of
from an original, along with the low cost and correspondingly low quality of

copying. History
copying. History

The spirit duplicator was invented in 1923 by Wilhelm Ritzerfeld. The
The spirit duplicator was invented in 1923 by Wilhelm Ritzerfeld. The

best-known manufacturer in the US and the world was Ditto Corporation of
best-known manufacturer in the US and the world was Ditto Corporation of

Illinois, while copiers available in the UK were commonly manufactured by the
Illinois, while copiers available in the UK were commonly manufactured by the

Block & Anderson company, under their "Banda" brand. In both cases the
Block & Anderson company, under their "Banda" brand. In both cases the

trademark became a generic name for both the copiers and the process in their
trademark became a generic name for both the copiers and the process in their

respective markets. Spirit duplicator technology gradually
respective markets. Spirit duplicator technology gradually

fell into disuse starting in the 1970s after the availability of low-cost,
fell into disuse starting in the 1970s after the availability of low-cost,

high-volume xerographic copiers. By the turn of the 21st century, the use of the
high-volume xerographic copiers. By the turn of the 21st century, the use of the

technology was rare. The technology remains useful where electrical power is
technology was rare. The technology remains useful where electrical power is

unavailable, or where the only remaining originals of legacy documents requiring
unavailable, or where the only remaining originals of legacy documents requiring

duplication are in "spirit master" form. Tattoo artists use the master copies
duplication are in "spirit master" form. Tattoo artists use the master copies

these machines produce as the transferred design makes a very durable
these machines produce as the transferred design makes a very durable

print on the skin that resists smudging as excess ink is wiped off during the
print on the skin that resists smudging as excess ink is wiped off during the

process. It is perhaps the only modern-day usage of such a device;
process. It is perhaps the only modern-day usage of such a device;

industry-specific machines that produce the prints are now available as artists
industry-specific machines that produce the prints are now available as artists

in the past have coveted and exhausted the supply of older models leftover.
in the past have coveted and exhausted the supply of older models leftover.

The faintly sweet aroma of pages fresh off the duplicator was a memorable
The faintly sweet aroma of pages fresh off the duplicator was a memorable

feature of school life in the spirit-duplicator era. A pop culture
feature of school life in the spirit-duplicator era. A pop culture

reference to the aroma can be found in the 1982 film Fast Times At Ridgemont
reference to the aroma can be found in the 1982 film Fast Times At Ridgemont

High. At one point a teacher distributes a duplicated schedule of class quizzes,
High. At one point a teacher distributes a duplicated schedule of class quizzes,

and every student immediately lifts it to his or her nose and inhales. The
and every student immediately lifts it to his or her nose and inhales. The

blues band Saffire - The Uppity Blues Women has another perspective in their
blues band Saffire - The Uppity Blues Women has another perspective in their

song "School Teacher's Blues," which has the lines, "My fingers have turned
song "School Teacher's Blues," which has the lines, "My fingers have turned

purple, My master's like I chewed it, my mind is getting warped from inhaling
purple, My master's like I chewed it, my mind is getting warped from inhaling

Ditto fluid." Design
Ditto fluid." Design

The duplicator used two-ply "spirit masters". The first sheet could be
The duplicator used two-ply "spirit masters". The first sheet could be

typed, drawn, or written upon. The second sheet was coated with a layer of
typed, drawn, or written upon. The second sheet was coated with a layer of

wax that had been impregnated with one of a variety of colorants. The pressure
wax that had been impregnated with one of a variety of colorants. The pressure

of writing or typing on the first sheet transferred the colored wax from the
of writing or typing on the first sheet transferred the colored wax from the

second sheet to the shiny/coated back side of the first sheet, producing a
second sheet to the shiny/coated back side of the first sheet, producing a

mirror image. This produced the same result of a sheet of carbon paper put in
mirror image. This produced the same result of a sheet of carbon paper put in

backwards. The two sheets were then separated, and the first sheet was
backwards. The two sheets were then separated, and the first sheet was

fastened onto the drum of the machine, with the back side facing out, acting as
fastened onto the drum of the machine, with the back side facing out, acting as

a printing plate. There is no separate ink used in spirit
a printing plate. There is no separate ink used in spirit

duplication, as the wax transferred to the back side of the first sheet
duplication, as the wax transferred to the back side of the first sheet

contained the ink. As the paper to be printed moved through the printer, the
contained the ink. As the paper to be printed moved through the printer, the

solvent was spread across each sheet by an absorbent wick. When the
solvent was spread across each sheet by an absorbent wick. When the

solvent-impregnated paper came into contact with the back side of the first
solvent-impregnated paper came into contact with the back side of the first

sheet, it dissolved just enough of the pigmented wax to print the image onto
sheet, it dissolved just enough of the pigmented wax to print the image onto

the paper as it went under the printing drum.
the paper as it went under the printing drum.

= Colors = The usual wax color was aniline purple,
= Colors = The usual wax color was aniline purple,

a cheap, moderately durable pigment that provided good contrast, but masters were
a cheap, moderately durable pigment that provided good contrast, but masters were

also manufactured in red, green, blue, black, and the hard-to-find orange,
also manufactured in red, green, blue, black, and the hard-to-find orange,

yellow, and brown. All except black reproduced in pastel shades: pink, mint,
yellow, and brown. All except black reproduced in pastel shades: pink, mint,

sky blue, and so on. Spirit duplicators had the useful
sky blue, and so on. Spirit duplicators had the useful

ability to print multiple colors in a single pass, which made them popular
ability to print multiple colors in a single pass, which made them popular

with cartoonists. Multi-colored designs could be made by swapping out the waxed
with cartoonists. Multi-colored designs could be made by swapping out the waxed

second sheets; for instance, shading in only the red portion of an illustration
second sheets; for instance, shading in only the red portion of an illustration

while the top sheet was positioned over a red-waxed second sheet. This was
while the top sheet was positioned over a red-waxed second sheet. This was

possible because the duplicating fluid was not ink, but a clear solvent.
possible because the duplicating fluid was not ink, but a clear solvent.

The duplicating fluid typically consisted of a 50/50 mix of isopropanol
The duplicating fluid typically consisted of a 50/50 mix of isopropanol

and methanol, both of which were inexpensive, readily available in
and methanol, both of which were inexpensive, readily available in

quantity, evaporated quickly, and would not wrinkle the paper.
quantity, evaporated quickly, and would not wrinkle the paper.

In 1938 a nonflammable solvent was invented by Johan Bjorksten to allow the
In 1938 a nonflammable solvent was invented by Johan Bjorksten to allow the

possibility of using electrically driven machines without the concern of the
possibility of using electrically driven machines without the concern of the

flammability of pure methyl/ethyl alcohol. "A composition composed of 10%
flammability of pure methyl/ethyl alcohol. "A composition composed of 10%

of monofluoro tri-chloro methane and 90% of a mixture of 50% methyl alcohol, 40%
of monofluoro tri-chloro methane and 90% of a mixture of 50% methyl alcohol, 40%

ethyl alcohol, 5% water and 5% of ethylene glycol mono-ethyl ether. This
ethyl alcohol, 5% water and 5% of ethylene glycol mono-ethyl ether. This

solvent mixture is non-flammable in the closed space of the reservoir and has a
solvent mixture is non-flammable in the closed space of the reservoir and has a

flash point of 100°F. when fully exposed to air. The solvent mixture has a
flash point of 100°F. when fully exposed to air. The solvent mixture has a

pleasant odor, reduced toxicity and gives at least as good copies as the
pleasant odor, reduced toxicity and gives at least as good copies as the

duplication liquid before the addition of the mono-fluoro tri-chloro methane.
duplication liquid before the addition of the mono-fluoro tri-chloro methane.

It is believed that the high efficiency of mono-fluoro tri-chloro methane as a
It is believed that the high efficiency of mono-fluoro tri-chloro methane as a

flame reducing agent is due to the fact that its boiling point is sufficiently
flame reducing agent is due to the fact that its boiling point is sufficiently

low as to cause the formation of a non-flammable vapor, film on the surface
low as to cause the formation of a non-flammable vapor, film on the surface

of the organic solvent, with sufficiently high boiling point as to be
of the organic solvent, with sufficiently high boiling point as to be

substantially retained by the solvents even at high summer temperatures."
substantially retained by the solvents even at high summer temperatures."

This process worked best with cheap, lightweight paper stocks, but when the
This process worked best with cheap, lightweight paper stocks, but when the

sheets of paper were impregnated with the solvent they could easily crease or
sheets of paper were impregnated with the solvent they could easily crease or

crumple, jamming the machine. One well-made master could print about 500
crumple, jamming the machine. One well-made master could print about 500

copies before the pigment was exhausted and the print became illegible. If fewer
copies before the pigment was exhausted and the print became illegible. If fewer

copies were required, the master could be removed from the printing drum and
copies were required, the master could be removed from the printing drum and

saved for future use. Durability
saved for future use. Durability

Dittoed copies now pose a serious challenge to archivists responsible for
Dittoed copies now pose a serious challenge to archivists responsible for

historic document and artistic preservation. Dittoed images gradually
historic document and artistic preservation. Dittoed images gradually

fade with exposure to ultraviolet light, limiting their usability for permanent
fade with exposure to ultraviolet light, limiting their usability for permanent

labels and signage. When exposed to direct sunlight, ditto copies can fade
labels and signage. When exposed to direct sunlight, ditto copies can fade

to illegibility in less than a month. The low-quality paper often used would
to illegibility in less than a month. The low-quality paper often used would

yellow and degrade due to residual acid in the untreated pulp. In the worst
yellow and degrade due to residual acid in the untreated pulp. In the worst

case, old copies can literally crumble into small particles when handled.
case, old copies can literally crumble into small particles when handled.

See also Duplicating machines
See also Duplicating machines

Hectograph Fordigraph
Hectograph Fordigraph

List of duplicating processes References
List of duplicating processes References

Further reading Information Processing Equipment. Edited
Further reading Information Processing Equipment. Edited

by M.P. Doss ... Contributors: Hubbard W. Ballou [and Others], Etc. New York.
by M.P. Doss ... Contributors: Hubbard W. Ballou [and Others], Etc. New York.

1955. Irvin Albert Herrmann. Manual of Office
1955. Irvin Albert Herrmann. Manual of Office

Reproduction: Reproduction Processes, Systems Duplicating. Office Publishing
Reproduction: Reproduction Processes, Systems Duplicating. Office Publishing

Company.
Company.