U.S. patent number 3,854,942 [Application Number 05/321,511] was granted by the patent office on 1974-12-17 for transparency for multi-color electrostatic copying.
This patent grant is currently assigned to Xerox Corporation. Invention is credited to Alptekin Akman.
United States Patent |
3,854,942 |
Akman |
December 17, 1974 |
**Please see images for:
( Certificate of Correction ) ** |
TRANSPARENCY FOR MULTI-COLOR ELECTROSTATIC COPYING
Abstract
A transparency is disclosed, which is suitable for use in a
multi-colored xerographic reproduction process comprising a
transparent, thermoplastic film sheet having at least one surface
coated with a mixture consisting of a vinyl chloride-acetate
copolymer resin and an acrylic resin in a weight ratio of between
about 6:4 and 7:3, with a wetting agent in said mixture in an
amount between about 2.5 to 25% by weight of said mixture. In a
preferred embodiment, a percentage of a particulate material is
also incorporated in the coating to reduce static charge on the
transparency and permit easier handling thereof. The coated
transparency, when used in a multi-colored electrostatic copying
process improves adhesion of the multi-colored image thereon and
permits reproduction of colors and color densities in said image
which correspond well to the multi-colored original copied.
Inventors: |
Akman; Alptekin (Ontario,
NY) |
Assignee: |
Xerox Corporation (Stamford,
CT)
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Family
ID: |
26929927 |
Appl.
No.: |
05/321,511 |
Filed: |
January 8, 1973 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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236585 |
Mar 21, 1972 |
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194547 |
Nov 1, 1972 |
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Current U.S.
Class: |
430/47.5;
430/124.52; 428/336; 428/419; 428/451; 427/393.5; 428/412; 428/443;
428/500 |
Current CPC
Class: |
C08J
7/043 (20200101); G03G 7/0013 (20130101); C08J
7/0427 (20200101); G03G 7/002 (20130101); C08J
7/046 (20200101); G03G 7/004 (20130101); Y10T
428/31667 (20150401); Y10T 428/265 (20150115); Y10T
428/31507 (20150401); Y10T 428/31533 (20150401); Y10T
428/31652 (20150401); Y10T 428/31855 (20150401) |
Current International
Class: |
C08J
7/04 (20060101); C08J 7/00 (20060101); G03G
7/00 (20060101); G03g 013/16 (); B44d 001/24 () |
Field of
Search: |
;117/17.5,76F,138.8A,138.8F,161UC,161UH,161UZ,21,63,16R
;96/1R,1.2,1.4 ;355/4,17 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Sofocleous; Michael
Parent Case Text
BACKGROUND OF THE INVENTION
This application is a continuation in part application of my
previous application under Ser. No. 236,585, filed Mar 21, 1972,
which application is a continuation in part of application Ser. No.
194,547 filed Nov. 1, 1972.
Claims
What is claimed is:
1. A transparency for the formation of an adherent electrostatic
image thereon comprising a thermoplastic film sheet, said sheet
having at least one surface coated with a mixture which comprises
an acrylic resin, and a vinyl chlorideacetate copolymer resin in a
weight ratio of between about 6:4 and 7:3, a wetting agent in an
amount of between about 2.5 to 25% by weight of said mixture with
an effective amount of a particulate material in said mixture to
reduce the static properties of said sheet.
2. A transparency as set forth in claim 1 wherein said particulate
material is present in an amount of between about 1 to 20% by
weight of said resins.
3. A transparency as set forth in claim 1 wherein said particulate
material is asbestos, silica or colloidal silica.
4. A transparency as set forth in claim 1 wherein said
thermoplastic film sheet is polysulfone or polycarbonate.
5. A transparency as set forth in claim 1 wherein said coating on
said sheet has a thickness of between about 0.1 and 0.7 mils.
6. A transparency for the formation of an adherent, multi-colored
electrostatic image thereon comprising a thermoplastic film sheet,
said sheet having at least one surface coated with a mixture which
comprises an acrylic resin and a vinyl chloride-acetate copolymer
resin in a weight ratio of between about 6:4 and 7:3, a wetting
agent in an amount of between about 2.5 to 25% by weight of said
mixture and a particulate material in an amount of between 1 to 20%
by weight of said resins to reduce the static properties of said
sheet.
7. A transparency as set forth in claim 6 wherein said particulate
material is asbestos, silica or colloidal silica.
8. A transparency as set forth in claim 6 wherein said
thermoplastic film sheet is polysulfone or polycarbonate.
9. A transparency as set forth in claim 6 wherein said coating on
said sheet has a thickness of between about 0.1 and 0.7 mils.
10. A method of xerographically preparing a color transparency copy
comprising:
a. forming a single color powder image of a multi-colored original
to be reproduced;
b. transferring the powder image to a transparency comprising a
thermoplastic film sheet, said sheet having at least one surface
coated with a mixture which comprises an acrylic resin, and a vinyl
chloride-acetate copolymer resin in a weight ratio of between about
6:4 and 7:3, a wetting agent in an amount between about 2.5 to 25%
by weight of said mixture with an effective amount of a particulate
material in said mixture to reduce the static properties of said
sheet; and
c. fixing the powder image on the transparency.
11. The method of claim 10 wherein the steps of powder image
formation and transfer are repeated before the fixing step, each
sequence corresponding to the formation of a different color to
effect multi-color reproduction, said transfer of each developed
electrostatic image taking place in registration on the
transparency.
12. The method of claim 10 wherein the fixing is carried out by
vapor fusion.
13. The method of claim 10 wherein the transparency used in
transfer step contains particulate material in an amount of about 1
to 20% by weight of the resin material.
14. The method of claim 10 wherein the coating on the transparency
used in the transfer step has a thickness of about 0.1 to 0.7
mils.
15. The method of claim 10 wherein the transparency used in the
transfer step contains asbestos, silica or colloidal silica as a
bulking agent.
16. The method of claim 10 wherein the transparency used in the
transfer step is a thermoplastic film sheet of polysulfone or
polycarbonate.
17. The method of claim 10 wherein the step of forming a single
color powder image comprises:
a. exposing a charged photoconductive member to a filtered light
image of the multi-colored original to record a single color
electrostatic latent image thereon; and
b. developing the single color electrostatic latent image with
toner particles complementary in color thereto.
Description
This invention relates to xerographic reproduction and specifically
to transparencies which are suitable for use in a xerographic
reproduction process.
Transparencies are a highly useful product in visual education
since an image on a transparency may be projected with the
necessary degree of magnification onto a screen where it may be
viewed by a large number of persons. Transparencies have heretofore
been made by photographic reproduction of the desired image and
accordingly been required the skill of an individual who is
familiar with complex photographic reproduction processes.
Photographic reproduction of transparencies also requires the
expenditure of a large amount of time and money and is thus
undesirable for this reason. Therefore, an easy and inexpensive
means for the production of transparencies has been sought whereby
transparencies could be conveniently and economically imaged and
then used an unlimited number of times in visual education
programs.
The advent of xerography and electrostatic copying as generally
disclosed by Carlson in U.S. Pat. No. 2,297,691 has proven to be a
highly successful process for reproduction with the inherent
advantages of speed and reliability. In a usual xerographic
process, an electrostatic image on an object as formed on a
recording member such as a xerographic plate or drum. The
xerographic plate may comprise a layer of photoconductive material,
such as selenium on a conductive metal backing. The latent
electrostatic image which is formed on the photoconductive material
is developed into a powder image which is then subsequently
transferred to a sheet of paper and affixed thereon to form a
permanenet print.
The xerographic process has therefore proven to be an easy and
reliable means for the production of transparencies. Transparencies
made by a xerographic process are produced by forming an
electrostatic image of the desired object, developing it, and then
transferring it to a transparent sheet material with the image
being permanently affixed or fused thereto by either the
application of heat or by the action of a solvent vapor. In either
case the toner which is used to develop the powdered image is
coalesced on the sheet material by the fusing technique to form a
permanent image thereon. Solvent fusion techniques, for transparent
materials made by a xerographic process, for example, are
illustrated in U.S. Pat. Nos. 3,049,810 and 3,148,078.
While the xerographic reproduction process is an apparent solution
to the problem of economical and efficient production of
transparencies, other problems have also been encountered with its
use in the production of transparencies. One of the most pronounced
problems with producing transparencies by an electrostatic copying
process is to get the powdered or developed image to adhere well to
a transparent film material before the image is permanently affixed
thereto by fusing. Failure to achieve this, results in partial or
"cracked" images. A further problem encountered in obtaining proper
and uniform density of the image after fixing or fusion and without
resultant damage to the transparent film material either in the
fusion process or in the transfer system employed within the
machine. For this reason, various coating and combinations thereof
with various types of transparent sheet materials have been
previously proposed to obviate some of these difficulties. Included
are various single component polymeric coatings such as are
exemplified in U.S. Pat. Nos. 3,539,340; 3,539,341 and
3,535,112.
The above coatings, while of some assistance in improving adhesion
of the developed electrostatic image to a transparent film
material, nevertheless, are not entirely suitable when
transparencies are produced by a multi-colored xerographic imaging
process. The difficulties encountered with a multi-colored imaging
process and transparencies produced thereby are due in part to the
multi-component pigment developers required in the multi-colored
imaging process and their varying degree of attraction for the
transparent sheet material. Furthermore, the problem of getting the
correct degree of coalescence of the toner particles in the
permanent image is an even more critical matter with multi-colored
imaging than with single color image development. This increased
criticality is due to the fact that single color transparent images
only require complete opaqueness or non-opaqueness of varying
degrees to produce a transparency which has images suitable for
projection.
Multi-colored transparency images, on the other hand, must allow
for a certain degree of color density for each color or color
combination in the image which is sufficient and uniform enough to
allow projection of a uniform and true color. This therefore,
requires a different and unique combination of materials being
employed and more critical controls being immposed upon the
transparent materials which are used in a multicolor xerographic
imaging process to obtain the correct degree of attraction of toner
to the transparent sheet as well as proper coalescence of toner
particles for good color density.
It is an object of the present invention therefore, to provide for
a transparency upon which a multi-colored xerographic image may be
permanently affixed with uniform and consistent color reproduction
and density.
It is also an object of the present invention to provide a
transparency which is permanent in nature and having the sheet
strength necessary to allow repeated use thereof for visual
education purposes.
It is also an object of the present invention to provide for
production of a color transparency by a xerographic multi-color
imaging process which in turn eliminates the skill of a technician
who is trained in reproduction photographic processing.
These and other objects, as well as the scope, nature and
utilization of invention will be apparent by the following detailed
description and appended claims.
SUMMARY OF THE INVENTION
It has now been determined that the general objective of producing
a transparency which will permanently hold a true and consistent
multi-color xerographic image may be best achieved by utilizing a
transparent, thermoplastic, film sheet such as a polysulfone or
polycarbonate sheet material, followed by the coating of this sheet
prior to xerographic imaging with a mixture of a vinyl
chloride-acetate copolymer resin, an acrylic resin, such as poly
n-alkyl methacrylate, and a wetting agent such as a quaternary
ammonium salt or fatty acid amide. It is this coating composition
which has been found to insure that all colored pigments required
in the multi-colored reproduction process are properly attracted to
and held by the transparent sheets during imaging and sheet
transfer so that a permanent image having uniform and accurate
color densities may be then fused on the transparent sheet. This
coating overcomes the previously noted difficulties with producing
a transparency by a multi-colored electrostatic copying process,
among which are poor adherence of the developed xerographic image
on the transparent film, as well as difficulty in insuring that a
consistent and true color density is developed from the colored
original which will also be suitable for projection or
magnification on a screen. As indicated, these problems while
existing with single color xerographic imaging, are even more
pronounced when a multi-colored xerographic process is
employed.
It has been further determined that if the coating mixture also
includes a particulate material which is relatively inert, such as
for example, asbestos, silica, colloidal silica and the like, the
coated transparency is characterized by an exceptional reduction in
its static properties to allow easy handling of the transparency
through the frictional paper handling system of the machine, as
well as permit multiple sheet feeding through the machine without
jamming or sticking therein. Sheets which are coated with a mixture
containing an effective amount of a particulate material to reduce
the static properties of the sheet, also assist in toner transfer
to the sheet during development, since if a high degree of static
charge builds up on the sheet because of friction through the
handling system, it can reduce the degree of attraction for the
electroscopic toner particles used to develop the image and in fact
may repel the toner particles thus preventing development of the
image. The coating which also includes a particulate material
therein, because of a reduction in static charge buildup, assists
in toner transfer to transparent films.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the process of multi-colored xerographic reproduction, a
subtractive color to color reproduction technique is used to
develop images formed on the photoconductive layer. Furthermore, a
multi-color xerographic imaging process may also employ multiple
scanning of the colored original at different wavelengths of light
to produce multiple images corresponding to each primary color
involved in the original. These primary color images may be then
recombined to form a single multi-colored image corresponding to
the original by using a multi-component or multi-colored toner in a
subtractive color to color reproduction process. A subtractive
color to color reproduction process is illustrated in U.S. Pat. No.
3,057,720.
Toners which are employed in multi-color xerography use subtractive
primary colors, yellow, cyan (blue green) and magenta. These in
turn are used to reproduce a wide gamut of colors normally found in
the colored original. For the purposes of illustration, when
subtractive mixing of the yellow and cyan colorants take place,
greens are obtained. Likewise, the mixing of magenta and yellow
colorant in varying amounts reproduces reds, while combining the
cyan with magenta results in the reproduction of blues. Mixtures of
equal amounts of each toner, of course, will produce a black
image.
Production of the multi-colored copy from the colored original may
be appropriately achieved by any multi-colored xerographic imaging
process. It is not intended that this invention be limited by
particular variations in the multi-colored xerographic imaging
processes that might be employed or with the equipment used in said
process. Nevertheless, for the purposes of illustration, a suitable
process for color imaging begins with proper discernment of the
color composition of the original subject matter and recording
thereof. This may be conveniently accomplished by sequential
optical scanning of the color original a number of times to
formulate a sequence of the latent electrostatic images which
correspond to the primary colors in the original. This is
accomplished by the light image passing through an appropriate
color filter so that the latent image is then in effect, color
separated according to the various primary colors. Theoretically,
the latent image which is formed by passing the light image through
a green filter should require the magentas (the complementary
color) as areas of relatively high charge density on the drum
surface, while the green (the separated color) should cause a
low-charged density level. The magentas are then made visible by
applying a green absorbing magenta toner to the image bearing
member. By the same token, a blue separation is developed with a
cyan toner. The three developed color separations are then brought
together in registration upon the final sheet of support material
to produce a multi-colored facsimile of the original colored
document copy.
It is this multi-component developer system used in a substrative
color to color reproduction process which presents numerous
problems when, for example, a color transparency is produced
thereby which will reproduce, with uniform and accurate consistency
the color densities which correspond to the colored original.
In the production of transparencies by a multi-colored xerographic
imaging process according to the present invention, a transparent,
thermoplastic film sheet material is selected as the support
material upon which the multi-colored xerographic image to be
developed. Although the sheet material may be any suitable
thermoplastic film material which has the clearness, strength and
heat resistance to allow repeated projection thereof, materials
which are particularly preferred for the present invention include
thermoplastic films made from theromplastic resins such as the
polysulfones or polycarbonates.
Thermoplastic sheet material which may be conveniently utilized in
the present invention includes polysulfone sheet materials which
are commercially available from Rowland Products Inc., Kensington,
Connecticut and Instar Supply Co., Inc., New York, N.Y. under the
name Folacron PSN, as well as polycarbonate sheet materials
commercially available from General Electric Corp., Waterford, N.Y.
under the name Lexan SL 1007. These materials may be selected from
any thickness range desired, although in selecting film thickness,
the films should be thick enough to have the necessary strength but
still be thin enough to remain flexible throughout continuous use
thereof. A suitable thickness of the film suitable for use in
xerographic imaging, will generally be 3 to 8 mils.
The thermoplastic film material is then coated with a mixed,
polymeric coating composition which has been found to significantly
improve adhesion of a multi-colored xerographic image to a
transparency during the xerographic development process while at
the same time during image fusion, permitting accurate reproduction
of color density of the transparency. The coating in this regard
has been found to assist in permanent fixing or fusing of the
developed image to the transparency by either solvent vapor or heat
fusion techniques, although solvent vapor fusion is preferred as
the method of fusion for transparencies produced according to the
present invention.
In a preferred embodiment of the present invention, it has also
been determined that if the coating contains a relatively inert
particulate material, a transparency is provided which is
characterized by an exceptional reduction in its static properties,
permitting easier handling thereof as well as permitting multiple
sheet feeding of the sheets through the paper handling system
without feeding problems from the paper feeding tray.
The coating developed herein comprises a mixture of a vinyl
chloride-acetate copolymer resin, an acrylic resin such as a poly
n-alkyl methacrylate, and a wetting agent such as a quaternary
ammonium salt or fatty acid amide and as a preferred embodiment,
incorporation of a relatively inert particulate material. This
coating mixture will be normally applied to the transparent film
material in the form of a solution and because of this, the choice
of solvents to provide the solution is important, relative to the
coating composition, since it must not cloud or change the film
material and it must at the same time provide enough solubility for
the coating composition to provide a clear uniform coating on the
transparency with no evidence of component insolubility. It will,
of course, be understood that when a coating mixture is employed
which contains a relatively inert particulate material, the latter
will ordinarily be insoluble, being in suspension in the solution
of the other components of the coating mixture.
The solvent composition found to be suitable for use with the
present composition and for its application to transparencies
produced therewith is a mixture of 2-ethoxy ethanol and a ketone,
preferably methyl isobutyl ketone. The mixture of these solvents
which is used to dissolve the coating composition of the present
invention will preferably comprise between about 2.5 to 3.0 parts
of 2-ethoxy ethanol to 1 part of the ketone, although variations in
the amount of these solvents may be made depending on the specific
materials employed out of the group that will work.
The proper amounts of the coating composition are then added to the
aforementioned solvent mixture and dissolved. The preferred amounts
of materials utilized in the coating composition of the present
invention include a ratio of the acrylic resin to the vinyl
chloride-acetate copolymer resin of between about 6:4 and 7:3 by
weight of the mixture. If the ratio of these two ingredients falls
above this range, an undesirable tackiness would result with the
coating, while if the ratio falls below this range, poor image
adhesion results. The wetting agent is also in an amount of between
2.5 to 25% by weight of the coating composition mixture, and this
percentage range increases toner transfer to the film substrate as
well as produce a more uniform consistent and brilliantly colored
image.
In the preferred embodiment of the present invention, a particulate
material is included in the coating composition in an amount of
between about 1 and 20% by weight of the polymeric components of
the mixture, i.e., the acrylic and vinyl chloride-acetate copolymer
resin. This particular percentage range has been found to be the
most effective means for reducing static charge buildup on the
transparent sheet through the paper handling system of the machine
under varying conditions of relative humidity. Obviously, since the
degree of static charge buildup will be somewhat dependent on the
relative humidity of the environment, the percentage of particulate
material may be varied over a wider range depending on the amount
that is needed to reduce the static charge to an acceptable level
without a deleterious effect on the transparency of the sheet.
The particulate material which is added to the coating for
reduction of the static charge on the transparent sheet under
handling conditions; adds a degree of "bulk" to the coating and due
to its protrusion through the coating imparts a certain degree of
roughness or texturing on the transparency surface, even though
this texturing may not be be readily discernible to the unaided
eye. This texturing or roughness succeeds in reducing the static
charge buildup on the transparency surface during handling by
frictional contact by reducing the surface area of the sheet which
is in contact with other frictional surfaces in the sheet handling
system of the machine, since contact with the sheet surface occurs
only through the particulate material. This minimal surficial
contact will result in a sheet which exhibits little static buildup
during handling, development and transfer and permits easy machine
feeding thereof. It is therefore, the proper combination of these
components which is critical for proper fixing and adhesion of the
multi-colored xerographic image to the transparency. It is also
this combination of ingredients which allows correct reproduction
of color density in the fused image, as well as giving strength to
the film which is needed for sheet transfer during copying and
continuous use of the transparency after formation. The ingredients
used must also be compatible with the multi-component toners used
for the subtractive color reproduction processes and accordingly
prevent precipitation or deposition of the toner as discrete,
recognizable, particles in the final developed image as opposed to
coalescence and formation of a uniform and consistent toner film.
If the toner is deposited as recognizable and discrete particles,
then an image is produced which has a "dirty" or spotty look and
the color density thus becomes eratic. The coating materials must
therefore be comparible with the toner materials used to develop
the multi-color images, while at the same time being transparent
and yet strong enough to permit normal handling of
transparencies.
The vinyl chloride-acetate copolymer material which may be used in
the coating composition of the present invention may be any
commercially available form of this material. Suitable for use, for
example, is that copolymer material manufactured by Union Carbide
Corp., including Bakelite VMCH. The vinyl chloride-acetate
copolymer resin material imparts the necessary toughness to the
film and the image which is produced thereon to prevent scratching
of the image or the film besides also preventing excessive curling
of the transparency after subsequent fusion techniques.
The acrylic resin is added to and improves adhesion and fixing of
the toner and may be conveniently selected from among the various
poly n-alkyl acrylic resins such as the polymerized n-alkyl
methacrylates which are commercially available from E. I. duPont
deNemours and Co. and available under the trade name of Lucite.
Although various alkylated methacrylates will be suitable for use
in the present invention, nevertheless, the butyl methacrylates
such as Lucite 44, 45 and 46 are preferred for use in the present
coating composition.
A wetting agent is added to the coating composition of the present
invention to improve colored toner flow and coalescence over the
coating during the subsequent vapor fusing operation. The material
also aids in wetting the toner particles so as to give more
uniform, brilliant, and consistent colors besides improving color
density in the transparency. The addition of the wetting agent
further improves the surficial characteristics of the transparency
itself and assists in reduction of the static properties thereof,
at least under conditions of high humidity, in order to prevent
sticking together of the transparencies either before or after
imaging. Materials which are specifically preferred as the wetting
agents in the present invention are quaternary ammonium salts and
fatty acid amides such as are available from Armour Industrial
Chemical Co., Chicago, Ill. and sold under the trade name of Arquad
2 HT-75 Armid O, Armid C or Armostat 310.
In the preferred embodiment of the present invention, the
particulate material which is added to the coating to texturize the
surface of the transparency may be selected from a group of
relatively inert, particulate materials including asbestos, silica,
or colloidal silica and can be conveniently added to the coating
during dissolution of the polymeric materials. As previously noted,
a preferred range for addition is between about 1 to 20% by weight
of the mixture of polymeric components which comprise the vinyl
chloride-acetate copolymer resin and acrylic resins. This range of
addition allows for a sufficient degree of reduction of static
charge on the sheet under varying conditions of relative humidity
to permit easy handling and multiple sheet feeding without having a
deleterious effect on the clearness or transparency of the
thermoplastic film. It should be recognized however, that the
particulate material could be employed outside of this range
dependent on the ambient conditions the sheet might be used under
as long as an acceptable decrease in static properties of the sheet
occurs without affecting the transparency of the film sheet.
Transmission measurements made over the wavelength region of active
light on transparencies containing the particulate material
indicate substantially the same transmission is obtained with the
uncoated sheet as with the coated sheet containing the particulate
material.
The coating composition after dissolution in the appropriate
solvent mixture is applied to the transparent thermoplastic film by
techniques which are well known to those skilled in the art of
paper coating. Various techniques which are suitable for coating
could be by roll, air knife, or any other uniform application means
used in paper coating. For instance, the coating may be simply
passed through a hopper containing the coating composition in
liquid form, which is provided by a doctor blade on the coating may
be applied by use of a more precise coating apparatus such as a
gravure press. Preferably a coating of between about 0.1 and 0.7
mils thickness is produced upon the transparent thermoplastic film
sheet after evaporation of a solvent or solidification of the
dissolved polymeric materials. Since the polymeric coating on the
sheet is in the nature of an extremely thin film, no significant
impairment of the transparency of the sheet itself results from its
presence and the transparency formed therfrom by electrostatic
image, processes the requisite degree of clearness to be
satisfactory for most visual education purposes.
The following is giving a specific illustration of the present
invention although it should be understood that the invention is
not intended to be limited to specific details to be set forth
thereon.
EXAMPLE 1
A transparent, thermoplastic film material with dimensions of 81/2
.times. 11 inches consisting of a polysulfone transparent sheet
having a thickness of 5 mils was used as the substrate for a
coating composition which was prepared by forming a solution of 45
parts of 2-ethoxyethanol, and 15 parts of methyl isobutyl ketone,
followed by the addition thereto of:
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin (86% vinyl chloride,
13% acetate)
0.5 g. dialkyl quaternary ammonium chloride
(Arquad 2 HT-75, Armour Industrial Chemical Co.)
This was mixed until a clear solution was obtained followed by the
application of the coating composition to the polysulfone sheet
with a No. 20 Mayer Rod, followed by drying of the coated sheet
with warm air. After evaporation of the solvents used in applying
the coating, a coating thickness of about 0.3 mils was
obtained.
The coated transparent sheet material was subjected to a
multi-colored xerographic imaging process with resultant vapor
fusion of the adherent multicolored image. It was observed that
superior image adhesion occurred both before and after vapor fusion
and more toner transfer was obtained with a highly uniform and
accurate colored image being formed. The colors reproduced were
uniformed, with consistent color density and no evidence of toner
"spotting." Additionally, the multi-colored transparencies
exhibited low frictional and static properties when compared with
uncoated transparencies.
EXAMPLE 2
The procedure of Example 1 was followed with the exception that to
the solution of 45 parts of 2-ethoxyethanol, and 15 parts of methyl
isobutyl ketone, the following mixture was added:
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate)
0.5 g. fatty acid amide
(Armid O, Armour Industrial Chemical Co.)
This was mixed well with the solvents until a clear solution was
obtained, followed by application to the polysulfone sheet material
as set forth in Example 1. The resultant coating thickness after
drying measured about 0.3 mils.
This coated transparent sheet material was subjected to a
multi-colored xerographic imaging process, and superior image
adhesion to the transparent sheet occurred both before and after
vapor fusion to fix the image. Furthermore, excellent toner
transfer to the sheet occurred with a resultant improvement in
uniformity of the colored image and the density thereof. The imaged
transparency also exhibited less friction and a decrease in static
properties, and the image thereon corresponded well in color to the
original.
EXAMPLE 3
The procedure of Example 1 was followed and with the exception that
to the solution of 45 parts of 2-ethoxyethanol and 15 parts of
methyl isobutyl ketone, the following mixture was added.
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate)
2.0 g. dialkyl quaternary ammonium chloride
(Arquad 2 HT-75, Armour Chemical Co.)
This was mixed well with the solvent mixture until a clear solution
was obtained followed by application to the polysulfone sheet
material as set forth in Example 1. The resultant coating thickness
after drying was about 0.3 mils.
When this coated transparent sheet material was subjected to a
multi-colored xerographic imaging process, superior image adhesion
resulted both before and after vapor fusion which was used to fix
the image. Furthermore, good toner transfer occurred with uniform
and consistent colors being produced which correspond well to those
of the colored original.
EXAMPLE 4
Three transparent polysulfone sheet materials as in Example 1 were
coated according to the procedure of Example 1 and were designated
as sheets A, B, and C. The sample designations corresponded to the
following formulations used to prepare the coating used for each
sheet.
Sample A:
8 g. n-butyl methacrylate
2 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate) dissolved in a mixture of
45 parts of 2-ethoxyethanol and 15 parts of methyl isobutyl
ketone.
Sample B:
5 g. n-butyl methacrylate
5 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate) dissolved in a mixture of
45 parts of 2-ethoxyethanol and 15 parts of methyl isobutyl
ketone.
Sample C:
2 g. n-butyl methacrylate
8 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate) dissolved in a mixture of
45 parts of 2-ethoxyethanol and 15 parts of methyl isobutyl
ketone.
Each coated sheet was subjected to a multi-colored xerographic
imaging process, with resultant examination of the quality of the
image on the transparent sheet material.
Sample A was observed to have good image quality with good color
density and uniformity although the coating had an undesirable
tackiness.
Samples B and C were observed to have good image quality with good
color density and uniformity although adhesion of the image before
and after vapor fusion was poor.
EXAMPLE 5
A series of six transparent, thermoplastic film sheets having
approximate dimensions of 81/2 .times. 11 inches consisting of
polysulfone material and with a thickness of 5 mils were used as
the substrates for the following six coating compositions, all of
which were prepared by forming a solution of 45 parts of
2-ethoxyethanol and 15 parts of methyl isobutyl ketone. Each of the
following mixtures were dissolved or dispersed in the solvent
mixture followed by their application to each of the respective
polysulfone sheets with a No. 20 Mayer Rod. The coated sheets were
dried with a current of warm air, and after evaporation of the
solvents used in applying the coating, a coating thickness of about
0.3 mils was obtained. The coated sheets were designated according
to the compositions used for the respective coating thereof
according to the following formulations.
Sheet 1:
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate)
1 g. wetting agent
(Armostat 310, Armour Industrial Chemical Co.)
Sheet 2:
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate)
1 g. wetting agent
(Armostat 310, Armour Industrial Chemical Co.)
0.1 g. asbestos
Sheet 3:
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate)
1 g. wetting agent
(Armostat 310, Armour Industrial Chemical Co.)
0.5 g. asbestos
Sheet 4:
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride, 13% vinyl acetate)
1 g. wetting agent
(Armostat 310, Armour Industrial Chemical Co.)
1 g. asbestos
Sheet 5:
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin
(86% vinyl chloride - 13% vinyl acetate)
0.5 g. wetting agent
(Armostat 310, Armour Industrial Chemical Co.)
1 g. asbestos
Sheet 6:
7 g. n-butyl methacrylate
3 g. vinyl chloride - acetate copolymer resin
0.5 g. wetting agent
(Armostat 310, Armour Industrial Chemical Co.)
1 g. colloidal silica
(Cab-o-Sil, Cabot Corporation)
After coating and drying, the six coated sheets were subjected to
feeding tests in a multi-colored electrostatic copier, and their
ability to machine feed evaluated. Further, the static and kinetic
coefficient of friction was measured for each coated sheet against
itself according to ASTM procedure D 1894-64, entitled Standard
Method of Test for Coefficients of Friction of Plastic Film and
compared against uncoated polycarbonate and polysulfone sheets. The
static or starting coefficient of friction expressed is related to
the force measured to begin movement of the surfaces of the two
sheets relative to each other, while the kinetic or sliding
coefficient of friction expressed is related to the force measured
in sustaining this movement. The transmission of certain sheets
containing the asbestos and silica was also measured at various
wavelengths of actinic light and compared to uncoated sheets. The
test results ae summarized as follows:
Polysulfone Polycarbonate Sheet Sheet (uncoated) (uncoated) Coated
Coated Coated Coated Coated Coated Control Control Sheet 1 Sheet 2
Sheet 3 Sheet 4 Sheet Sheet
__________________________________________________________________________
6 1. Machine Feeding Won't feed Won't feed Poor Fair Fair Good Good
Good Characteristics 2. % Transmission 420 m.mu.. 87% 88% 88% 560
m.mu.. 90% 89% 89% 700 m.mu.. 92% 89% 89% 3. Coefficients of
>1.0 .50/.44 .43/.44 .48/.48 .64/.59 .72/.66 .31/.27 .40/.45
Friction (static coefficient of friction/kinetic coefficient of
friction)
__________________________________________________________________________
It may be seen from the data set forth that the transparencies
which were coated with coating compositions which additionally
contained a particulate material such as asbestos or silica,
exhibited improved machine feeding properties and better
coefficients of friction than the coated sheets which did not
contain a particulate material.
Although the invention has been described both various embodiments,
it is understood that variations and modifications may be made as
will be apparent to those skilled in the art. Such reasonable
variations and modifications are furthermore considered to be
within the spirit and scope of the claims appended hereto.
* * * * *