Note: Descriptions are shown in the official language in which they were submitted.
BFN 6297 ~4~33
Background of the Invention
This invention relates to preprinted duplicating
masters for producing copies at least by the use of
pressure alone.
With the ever increasing work load on teachers
and instructors, it becomes important to use modern
technology to relieve the teachers of some of the duties
ordinarily undertaken. One tool of frequent use by
educators is the spirit duplication process for producing
copies of tests and instructional materials. Typically,
the teacher makes a master copy or master which in turn is
used to produce the plural copies.
The master is basically a sheet having
reverse-printed thereon an ink composition which when
contacted by a copy sheet having at least the surface wet
with a solvent or spirit material will transfer a portion
of that ink. Thus, plural copies of the master are made
by bringing the sheets to be printed into contact with the
reverse printed side of the master. U.S. Patent Nos.
2,748,024 to Xlinowski; 2,824,812 to Drautz; and 3,036,924
to Newman are examples of spirit duplicating ink
compositions and printing processes.
Initially, the masters were individually made
from a transfer sheet having a surface coating of a spirit
duplicating material. Using a typewriter, for example,
some of the material on the transfer sheet was transferred
to a sheet overlying the transfer sheet by striking the
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Docket 6297
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overlay sheet and causing the ink to be crash printed on
the overlay sheet.
It has been found ~hat it is aIso possible to
preprint masters with i~k compositions of the spirit
duplicating type. Then the teacher can use such preprinted
masters to make copies for students on a given sub]ect
without having to compose the assignment itself. But
the use of such preprinted masters still requires the use
of fluid spirits. In addition, the costs involved in
spirit duplicating because of the use of such fluids
are higher than a transfer process whiçh is capable '
of use without'fluid.
Also of interest in the background of this
invention are the pIastic structures which have an ink '
material dispersed therein and will'transfer some of that '
ink by the application of pressure. Such str~ctures
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are formed as printing plates, hand stamps, ink rollers
for printing processes, and the like, ~ut as far as known
have not been used in making preprinted duplicating
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' masters. They generally comprise a synthetic plastic
material and an inking material. The plastic acts as
an adhesive resinous vehicle; a porous, microreticulated
structure;' or a binder and retains the inking material
until it is exuded under pressure.' The plastic structure
is usually made by mixing the plastic with a'solvent
or plasticizer to form a paste, organosol, plastlsol or
the like and then shaping the plastic and curing by using
heat.' The inking material can be added to the plastic
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material before the shaping step or after the porous
structure is formed. Examples of such processes and
structures are U.S. Patent Nos. 3,037,879, '3,359,900
and 3,458,339 to Newman; U.S. Patent No. 3,436,234'to
Terry et al; and U.S. Patent Nos. 2,777,824; 3,055,297
and 3,101,668 to Leeds. Reference is also made to - -'
Champion patent 2,320,769. ~ -
Summary_of the Inve~tion
The present invention provides a preprinted '
duplicating master which will produce printed copies with
or without the use of spirit duplicating fluids. That
is, the improved preprinted duplicating master of the
lnvention can be used in the conventional spirit , '
duplicati~g process to,produce copies or the master can -~
be'used to make copies without employing spirits or
~ solvents but ~y the use of'pressure alone.
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The amount of dye used'in the ink o~ the
mast~rs of the present invention is less than normally
, used on spirit duplicating masters, and yet the number of
'copies obtained is nearly the same. 'In addition, because
the masters are subject to a fluidless transfer, copy -,
paper can be used which need not be of the grade
necessary in spirit duplicating systems. ~hat is, in
a spirit duplicating process, there is a tendency for the -
25, solvent on the copy paper to carry the ink into and through
the paper causlng the image to blur and the ink to bieed
through the copy paper. In certain'grades of paper this
is more' noticeable than in others. A fluidless transfer
process, however, does not have,this difficulty.
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Still further, the imaging material which is pre-
printed to form the master need not ~e specially formulated in
the sense of being frangible and yet transferable.
Accordingly, the invention in one aspect provides
a preprinted duplicating master for producing printed copies with
or without spirit duplicating fluids comprising a foundation
sheet having a predetermined pattern of imaging material reverse
printed directly thereon without the use of a transfer sheet,
said imaging material comprising a heat-gelled, non-fused vinyl
resin having a microporous structure and having dispersed within
the microporous structure an ink composition comprising a dye
in a solvent, said ink composition being releasable from the
microporous structure of said gelled resin and transferable in
said predetermined pattern to a substrate on the application of
; pressure while said gelled resin is retained on said foundation
sheet.
A protective cover sheet may be superposed over the
reverse printing to prevent inadvertent or accidental transfer
of the ink composition prior to the actual use of the master.
The invention in a further aspect provides a method
of producing a preprinted duplicating master for producing copies
with or without spirit duplicating fluids, comprising the
steps of: a) reverse printing in a predetermined pattern
directly on a foundation sheet without the use of a transfer
sheet an imaging material comprising a mixture of a vinyl resin
dispersion and an ink composition, comprising a dye in a solvent,
; and b) heating at least the printing on said reverse printed
sheet to gel but not fuse said vinyl resin dispersion whereby
said ink composition will be releasable from said gelled vinyl
resin dispersion and transferable in said predetermined pattern
by at least the application of pressure alone and thereby to
form a duplicating master having an imaging material thereon.
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The foundation sheet which is used may have already
been printed on the other surface with instructional material,
etc. The printing can be done as part of a continuous process
or a batch sheet-by-sheet basis. As one of ~he final steps,
the foundation material is cut or trimmed so as to make
individual sheets, if necessary, and the protective cover material
may be secured over the printing. In this form the sheets may
be bound into a booklet of masters arranged, for example, by
topic. In this way when the class reaches a point where a quiz,
exam or particular work lesson is appropriate, the teacher need
only extract the particular preprinted master from the booklet
and prepare copies. Alternatively, the individual sheets may be
placed in folders, envelopes, boxes, etc.
To use the master, the protective cover sheet is
removed or the master removed from the envelope or folder and
the printing on the master is brought into contact with a
substrate to transfer in the predetermined printed pattern a
portion of the releasable ink in the resin structure to the
substrate. The transfer can be done by using uniform pressure to
force the master and the substrate toward one another. The
application of pressure causes the ink to exude from the resin
structure. This permits use of the master to transfer to any
type of receptive surface, i.e., fabric, leather, wood, etc., and
not just a copy paper. Alternatively, a copy paper could have
at least a surface wet with a solvent or "spirit" matexial which
will dissolve a portion of the ink material and deposit it on the
copy paper as in an ordinary spirit duplicating process.
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Thus the present invention, an improved
preprinted duplicating master as well as the method of
making and using the master, allows for both dry and
-~ spirit duplication. When used in a spirit duplication
process, the Lmproved master will produce as many copies
as ~ne normally gets with presently available spirit
duplicating masters. Significantly, the masters of
the present invention produce usuable copies immediately
while in ordinary spirit duplication, the first few
copies are usually too light to use. Using a pressure
only, i.e., without fluid or spirits, the improved masters
of the invention normally will produce in excess of 150
copies, which can be compared to the Newman dry process
in Patent No. 3,359,900, which produces only up to about
25 copies.
- - Additionally when the fl~idless pro;ess-is used,
it is possible with ~he present masters to print both sides
of a copy sheet. This is because the copy sheet is kept
dry and the application to the reverse side is not
defeated by requiring that a copy paper become wet with
spirit material. In a spirit duplicating process the
wetting would create problems prohibiting ready application
of an image to the reverse side in a second pass.
It is, therefore, an object of the present
invention to provide an improved preprinted duplicating
master, as well as methods of making and using preprinted
duplioating masters, which will produce copies by use of
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Docket 6297
pressure alone.
Another object of the presen~ invention is to
provide a preprinted duplicating master which can also be
. used in a sPirit duplicating process producing as many
copies as conventional despite the-use of less dye in the
ink .
Other objects and advantages of the invention will
be apparent from the following description and the appended ;
claims.
Detailed Des r pL~on of the Invention
The preprinted duplicating masters of the invention
achieve the above objects by having reverse printed thereon a
resin composition which has a transferable ink composition
therein. This allows the masters to be used in either dry
duplicating processes or spirit duplicating processes. The
resin dispersion is preferably a mixture of vinyl resin and
an ink composition. The dispersion is applied to a founda-
tion sheet by printing the mlxture of vinyl resin and ink . .
composition in a reverse pattern and subsequently exposing
the mixture to sufficient heat or energy to gel (but not fuse)
the vinyl resin. The vinyl resin dispersion may be formed by
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~ ~ dispersing the vinyl material, polyvinyl chloride, homopolymer or
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copolymer either alone or with other copolymers in powder form
in the dye solvent itself or in a plasticizer to which dye
solvent is added. In either event the vinyl resin forms a
structure that holds the ink composition therein, but will
release a portion of the ink composition in resp~nse
to the application of the proper amount of pressure-or solvent.
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Docket 6297
In the event the dye solvent itself is to be the
dispersion medium, the resin is dispersed as a dry powder
directly into the dye solvent. A suitable solvent is
oleic acid. The spirit duplicating dye may be added to
the dye solvent before or after mixing with the vinyl
resin.
In the event the vinyl dispersion is to contain a
plasticizer, the plasticizer should be selected so as to
be compatible with the synthetic resin. An example of a
resin/plasticizer mixture is equal parts of dioctyl
phthalate and Geon (trademark) 120 x 241 from B.F.
Goodrich Co. (a dispersion grade polyvinyl chloride
resin), but other resins and plasticizers can be employed.
When a plasticizer is used, the resin may be
dispersed in the liquid plasticizer using a low-speed,
high-shear mixer, such as for example, a planetary or
internal mixer. The ratio of parts by weight of
plasticizer to parts by weight of resin used to make the
plastisol may range from 1/2 to 2. An ink composition
comprising spirit duplicating ink dissolved in a solvent
such as oleic acid is then added to the plastisol.
Additives also may be incorporated, as needed, to
develop the desired properties of the resin dispersions.
Examples of typical additives in~lude stabilizers,
copolymer resins of larger particle size than the main
resin, fillers, pigments, surface active agents, viscosity
modifiers and volatile thinners.
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Docket 6297 ~4~33
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However the resin dispersion is prepared, the ink composition
is preferably releasable from the gelled resin such that
the ink will maintain its integrity while being distributed
throughout the resin.dispersion and thus wi~l exude from
the resin structure when pressure is applied t~ereto.
The inX composition-is preferably a solution of a
dye in a solvent, with the dye and solvent preferably being
premixed usingC e.g., a normal speed mixer and some heat to
aid the dissolving, to form the ink composition before it
is added to the plastisol or mixed with the resin. If the
inX is to be able to be used in a spirit duplicating process,
in addition to the pressure duplicating process~ the ink
should be soluble in the solvent or spirit material. If
it is to be transferred to a substrate only temporarily, it
~onveniently should be water soluble so that it can be
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easily washed off. Normaily, the dye will comprise from
about 5% to 50% by weight of the ink composition. Although
a wide variety of dyes and solvents can be employed, a
typical inX composition which can be used in both the spirit
and pressure duplicating processes is a 10% solution of
crystal violet in an oleic acid solvent.
Other dyes which may be used instead of crystal
violet include other spirit soluble dyes such as methyl
violet, paper blue, etc. ~iXewise a number of other dye
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Docket 6297 11~4~33
solvents may be used instead of oleic acid. These include
alcohols, glycols, glycerols, polyglycols, and other fatty
acids including derivatives of oleic acid.
Usually the ink composition will comprise 30 to
75~ by weight of the ink-resin dispersion mixture, with
a typical example being 50% by weight of ink composition.
It is important that the resin-ink mixtur~, i.e., the
imaging material, contain a sufficient amount of dye to
tove the number of copies desired, have the rheological
properties necessary for preprinting, maintain its
viscosity upon aging, and, before gelling, be a homogenous
mixture.
The foundation sheet must be able to withstand the
gelling temperatures, e.g;, 60C up to about 175~C or more,
and have little tendency, due to absorption or chemical
reaction to change the properties of the imaging material.
.
The foundation sheet also must be such that the resin
dispersion, e.g., the vinyl, will remain adhered to the sheet
when making copies and only release the releasable ink. The
foundation sheet can be a plastic film, metal foil, treated
or coated paper, combinations and/or composites of plastic,
metal or paper, or the like, material. An example of a
suitable foundation sheet is a 3 mil polyester film, such
as a polyethylene terphthalate film.
To form the master the ink-resin mixture is
printed directly in a reverse printing process on the
foundation sheet. Rotogravure, letterpress, stenciling
or aniline printing techniques may be used to do the
pxeprinting. Preferably the ink-resin mixture is deposited
in ~ patterned layer between .5 and 3 mils thick. The
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printing is then heated, by hot air or infrared radiation,
for example, to between about 120C and about 175C for
- about 5 seconds to about 15 seconds to gel the resin in
the coating and thereby forming the duplicating master.
The printing process can be done as a continuous process
or on a batch, sheet-by-sheet basis.
Because the printing is sensitive to pressure,
it will be desirable to provide protection against acci-
dental transfer. Preferably a protective cover sheet is
applied as part of the printing process. The cover sheet
should have little tendency to absorb the releasable ink
or any other ingredient of the imaging material, and can
be attached by gluing, stapling or the like. An example of
a cover sheet is a grease resistant 20 pound basis weight
tissue paper. In addition to attaching a cover sheet, the
preprinted master may be cut or trimmed to size and/or
otherwise processed as is conventional with preprinted masters.
To use the preprinted duplicating masters of the
in~ention, the cover sheet is removed and the printed side of
the master is contacted with a substrate whlch is to receive
some of the printing on the master.
In the pressure alone printing process, uniform
pressure is applied to the master and the substrate in an
amount which is sufficient to cause a portion of the ink
?5 composition to exude from the gelled resin dispersion and
transferred to the substrate. The pressure contacting
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Docket 6297 ~i~4~33
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of the maY~er and the substrate is repeated until the
requisite number of copies are produced. Any type of
pressure application means -- such as a roller against a
flat surface, press, pair of rollers, or even hand ~res- -
S sure such as by burnishing with a blunt instrument may
be used. In addition, a spirit duplicating machine,
except without using the spirit solution, could be em- -
ployed. It has also been found that the dwell time in
the pressure application~aan be slgnificant in producing
copies having clean, sharp images. The exact amount of
pressure and time of application necessary to produce
desired number of copies varies, but can be readily deter-
mined by trial and error.
The use of the improved masters of the invention
in a conventional spirit duplicating process requires no
special preparations or apparatus, other than the ink com-
position being soluble in the spirit material. The splrit
material on the surface of the copy sheet will dissolve
a portion of the ink composition in the resin material and
t~ansfer the in~ composition in the predetermined printed
pattern to the copy sheet. The resin dispersion itself
will not be transferred, and the printing process is con-
tinued until the requisite or desired number of copies
have been produced.
An example of a formulation of the imaging
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mater~al, i.e., the ink resin dispersion mixture, and
methods of making and using the duplicating masters of
the invention, although the invention is not limited
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Docket 6297
thereto, is as follows:
Exemplary
Amount
Range of Amounts (Parts by
Ingredients (Parts by Weight) Weight)
Geon(Trademark)
120 x 241 (poly-
vinyl chloride
resin; dispersion
grade 10 -20 15
dioctyl phthalate 5 -40 15
crystal violet .20 -40 3
oleic acid
derivative 4 -40 27
Tribase E
~Trademark)
(basic lead
silicate sulfate) 0.5 - 3
viscosity modifier
(bentonite clay) 0 - 1 .5
The Geon (trademark - obtainable from B.F.
Goodrich Co.) resin and dioctyl phthalate were placed in a
suitable container and mixed using a low-speed, high-shear
mixer to form a plastisol. While the vinyl and
plasticizer were mixing, the crystal violet and oleic acid
derivative were mixed also in a suitable container using
heat, but with a normal speed mixer. Once the resin
reached the plastlsol stage, the Tribase E (trademark -
available from National Lead Co.) was added and mixed so
that it became thoroughly dispersed therein. Next, the
ink composition was added to-the plastisol and dispersed
throughout, followed by addition of the bentonite clay
thixotropic agent to form the printable mixture.
In another example Geon (trademark) 120 x 241
(polyvinyl chloride resin) in powder form was dispersed in
a methy7 violet - oleic acid derivative solution by mixing
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Docket 6297 11~33
together in a mixer. No dioctyl phthalate was used. In
this instance the ink-resin dispersion mixture is as in
the following exemplary amounts (with possible range also
given):
Exemplary
Range of Amounts Amount
Ingredients (Parts by Wei~ht) (Parts by Weight)
Geon(trademark~
120 x 241 (poly-
vinyl chloride
resin; dispersion
grade) 10 -20 15
methyl violet .20 -40 3
oleic acid
derivative 4 -40 27
Tribase E
(trademark)
(ba&ic lead
silicate sulfate) 0.5 - 3
viscosity
modifier
(bentonite clay) 0 - 1 .5
Mixtures prepared by both methods were then used
to print a predetermined reverse pattern on a 3 mil
polyester film sheet to a thickness of 1.5 mil~ After
printing, the sheet was heated to 130C for 10 seconds
to gel the resin and to form a duplicating master.
After trimming the sheet to an appropriate size,
the master was used in a conventional spirit duplicating
machine, except without the use of the spirit duplicating
fluid t SO that there was only pressure contact between the
master and the copy sheets. By the use of pressure alone,
150 copies were made, and each was legible.
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While the process and product herein described
constitute preferred embodiments of the inven~`ion, it is to
be understood that the invention is not limited to this
.precise process and product, and that changes may be made
S therein without departing from the scope of the invention
which is defined in the appended claims.
Wbat is claimed is:
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