U.S. patent number RE34,647 [Application Number 07/849,277] was granted by the patent office on 1994-06-28 for overprint aqueous varnish.
This patent grant is currently assigned to Petrolite Corporation. Invention is credited to Timothy J. Baker, John H. Woods.
United States Patent |
RE34,647 |
Baker , et al. |
June 28, 1994 |
Overprint aqueous varnish
Abstract
An overprint aqueous varnish has improved properties by having
incorporated therein a small amount of an aqueous mixture of a
finely divided hydrocarbon and certain high molecular weight
oxyalkylated primary alcohols.
Inventors: |
Baker; Timothy J. (Claremore,
OK), Woods; John H. (Tulsa, OK) |
Assignee: |
Petrolite Corporation (St.
Louis, MO)
|
Family
ID: |
46246929 |
Appl.
No.: |
07/849,277 |
Filed: |
November 2, 1992 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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422890 |
Nov 28, 1989 |
5008114 |
|
|
|
267064 |
Nov 4, 1988 |
4908063 |
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Reissue of: |
616475 |
Nov 21, 1990 |
05035946 |
Jul 30, 1991 |
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Current U.S.
Class: |
106/271;
106/31.61; 427/258; 427/411; 524/376 |
Current CPC
Class: |
B01F
17/0028 (20130101); C09D 5/024 (20130101); C09D
11/03 (20130101); C09D 123/30 (20130101); C09D
123/30 (20130101); C08L 2666/22 (20130101) |
Current International
Class: |
B01F
17/00 (20060101); C09D 11/02 (20060101); C09D
123/30 (20060101); C09D 123/00 (20060101); C09D
5/02 (20060101); C09D 004/00 (); C09D 011/12 () |
Field of
Search: |
;106/31R,2R,270,271
;427/258,395,411 ;524/458 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0059461 |
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Sep 1982 |
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EP |
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0310194 |
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Apr 1989 |
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EP |
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899612 |
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Jan 1982 |
|
SU |
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1305211 |
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Jan 1973 |
|
GB |
|
Other References
"Unithox.TM. Ethoxylates: New Solutions for the Puzzles in Your
Water-Based System"(1986). Petrolite Specialty Polymers Group.
.
"Laboratory Preparation of a Dispersion of Unithox.TM. Ethoxylated
Alcohols in Water," (1986). Unithox Ethoxylated Alcohols, Technical
Release 4007.0. Petrolite Specialty Polymers Group. .
"Potential End Use Applications for Unithox.TM. Ethoxylated
Alcohols," (1986). Unithox Ethoxylated Alcohols, Technical Release
4002.0. Petrolite Specialty Polymers Group. .
"Unilin Alcohols," Technical Release, Petrolite Specialty Polymers
Group (1985)..
|
Primary Examiner: Klemanski; Helene
Assistant Examiner: Jones; Deborah
Attorney, Agent or Firm: Pravel, Hewitt, Kimball &
Krieger
Parent Case Text
REFERENCE TO RELATED APPLICATIONS
The present application which is a divisional application of Ser.
No. 07/422,890, filed Nov. 28, 1989.Iadd., now U.S. Pat. No.
5,008,114 .Iaddend.is a continuation-in-part application of
co-pending U.S. patent application Ser. No. 267,064, filed Nov. 04,
1988.Iadd., now U.S. Pat. No. 4,908,063.Iaddend..
Claims
What is claimed is:
1. A .[.paper product bearing printing ink indicia protected by an
overprint aqueous varnish having a.]. formulation .[.enhancing
additive.]. .Iadd.capable of imparting improved slip properties
when added to either a water-based ink or a paper protecting
varnish composition, said formulation .Iaddend.comprising a mixture
of
a. a finely divided unoxidized polyethylene having a molecular
weight of about .[.700.]. .Iadd.300 .Iaddend.to about 3,000;
b. a finely divided oxidized polyethylene having a molecular weight
of about .[.700.]. .Iadd.300 .Iaddend.to about 3,000; and wherein
components a and b comprise 1-6% of the .[.mixture and;.].
.Iadd.mixture; and .Iaddend.
c. 2-40% .Iadd.of .Iaddend.an oxyalkylated essentially linear
alcohol represented by the formula
wherein x is about 8 to about 75 and n is about 2 to about 65 and
balance water.
2. The .[.product.]. .Iadd.formulation .Iaddend.of claim 1 wherein
x is about 19 to about 44.
3. The .[.product.]. .Iadd.formulation .Iaddend.of claim 1 wherein
n is about 4 to about 50.
4. The .[.product.]. .Iadd.formulation .Iaddend.of claim 2 wherein
n is about 4 to about 50. .[.5. The product of claim 1 wherein the
hydrocarbon
is a mixture of unoxidized polyethylene and oxidized
polyethylene..]. 6. The .[.product.]. .Iadd.formulation .Iaddend.of
claim .[.7.]. .Iadd.1 .Iaddend.wherein the oxidized polyethylene
mixture comprises about 55-95%
by weight of the polyethylene mixture. 7. A method of coating a
paper product comprising the steps of forming an aqueous mixture
of
a. a finely divided unoxidized polyethylene having a molecular
weight of about .[.700.]. .Iadd.300 .Iaddend.to about 3,000;
b. a finely divided oxidized polyethylene having a molecular weight
of about .[.700.]. .Iadd.300 .Iaddend.to about 3,000; and wherein
components a and b comprise 1-60% of the mixture and,
c. 2-40% of an oxyalkylated essentially linear alcohol represented
by the formula
wherein x is about 8 to about 70 and n is about 2 to about 65 and
balance water; adding the thus-formed aqueous mixture to an
overprint aqueous varnish; mixing the aqueous mixture and varnish;
and applying the
resulting mixture to a paper product bearing printing ink indicia.
8. The .[.product.]. .Iadd.method .Iaddend.of claim 7 wherein x is
about 19 to
about 44. 9. The .[.product.]. .Iadd.method .Iaddend.of claim 7
wherein n
is about 4 to about 50. 10. The .[.product.]. .Iadd.method
.Iaddend.of claim 8 wherein n is about 4 to about 50. .[.11. The
product of claim 7 wherein the hydrocarbon is a mixture of
unoxidized polyethylene and
oxidized polyethylene..]. 12. The .[.product.]. .Iadd.method
.Iaddend.of claim 7 wherein the oxidized polyethylene mixture
comprises about 55-95% by weight of the polyethylene mixture.
.Iadd.13. An aqueous varnish comprising the formulation of claim 1.
.Iaddend. .Iadd.14. An aqueous
varnish comprising the formulation of claim 6. .Iaddend. .Iadd.15.
The formulation of claim 6 wherein the oxyalkylated essentially
linear alcohol is of the formula
wherein x is between from about 19 to about 44. .Iaddend. .Iadd.16.
An aqueous varnish comprising the formulation of claim 15.
.Iaddend.
Description
FIELD OF THE INVENTION
1. Background of the Invention
This invention relates to a new and useful additive composition for
water-based inks and overprint aqueous varnishes. More
particularly, this invention relates to an aqueous dispersion for
use as a water-based ink and overprint varnish formulation additive
for improving the performance of such inks in terms of gloss,
adhesion, slip and the like and the performance of such varnishes
in terms of gloss, toughness, heat resistance, lubricity and the
like. Also, new additive compositions useful as a clear protective
coating of a substrate, such as a film or paper product, bearing on
its surface printed indicia are provided.
There are four (4) general classes of printing inks. There are
letter press and lithographic inks, also known as oil inks or paste
inks, and there are flexographic and rotogravure inks, also known
as solvent or liquid inks. This invention is concerned with a
particular class of flexographic and rotogravure inks which are
water-based. Although these inks have certain characteristics in
common with inks used in other printing processes, they form a
distinct class because of the character of the printing processes
in which they are used, their applications and their formulations.
The main distinction of flexographic and rotogravure inks is that
they are normally of low viscosity compared to other classes of
printing inks.
Flexographic and rotogravure inks have, in the past, been prepared
by dispersing pigments or other colorants in volatile organic
solvents such as alcohols, ketones and hydrocarbons. Due to
environmental problems associated with the use of inks formulated
with volatile organic solvents, water-based flexographic and
rotogravure inks are becoming more important.
In flexographic printing, a form of rotary letter press uses a
flexible plate, such as rubber, and fluid inks. Originally,
flexographic printing was primarily used for paper bag printing but
subsequently proved suitable for printing almost any kind of
flexible packaging material. Flexographic inks generally consist of
pigment dispersed in a vehicle made by dissolving one or more
resins in a solvent, such as a volatile organic solvent or water.
The water-based flexographic inks are widely used on paper and
paper board. The vehicles for water-based inks are usually made
from acrylic copolymers, acidic rosin esters, shellac, acidic
styrene copolymers and various additives, such as waxes. The
advantages of water-based inks include good press stability and
printability, absence of fire hazard and volatile organic solvent
emissions, convenience and the economy of water as a diluent and
for wash-up. Since the water-based inks do not use volatile organic
solvents, their use is gaining favor over the use of organic
solvent-based inks.
Rotogravure inks normally comprise a pigment, a resin, a polymer or
wax additive and a solvent. As in flexographic inks, water-based
rotogravure inks are gaining favor over organic solvent-based inks
because of environmental and worker hazard considerations
In general, water-based inks are a mixture of water, resin,
emulsifier or dispersing agent, a pigment and a polymer or wax
additive. There exists a need to improve water-based inks in terms
of gloss, maintenance, rub resistance, adhesion, slip, water
resistance and other desirable properties.
In general, overprint varnishes are aqueous emulsions of polymers,
such as acrylic and styrenic polymers which may also contain a
hydrocarbon wax. Overprint varnishes are used to improve the
properties of printed products which have been printed with
relatively low-grade (and low cost) inks. Thus, for products for
which very high quality printing is not necessary (e.g., cereal
boxes, cracker boxes, tissue boxes, pet food bags, etc.), overprint
varnishes offer an economical means of "up-grading" the appearance
and other properties of products printed with low cost inks.
Overprint varnishes are also used to improve the appearance and
tactile qualities of higher grade products, such as lithographic
magazine covers. There exists a need to improve the overprint
varnishes in terms of toughness, gloss, heat resistance, lubricity
and other desirable properties.
2. Prior Art
U.S. Pat. No. 2,925,349 discloses a polish which utilizes alcohols
having up to 20 carbon atoms as dispersants. Such alcohols may be
oxyethylated.
U.S. Pat. No. 3,533,811 discloses a water-based printing ink
comprising a water-missible organic solvent, film forming resins
which are soluble in the water-missible solvent, pigment, soluble
protein, a polymer latex and a volatile base. The water-missible
organic solvents which are used are lower aliphatic alcohols and
the lower alkylene glycols and their esters and ethers.
U.S. Pat. No. 3,563,910 discloses oxyalkylated alcohols having up
to 38 carbon atoms as emulsifiers for water/hydrocarbon
mixtures.
U.S. Pat. No. 3,884,707 discloses a water-based ink comprising a
basic dye, water, an organic solvent and a resin. The organic
solvents employed are, for example, ethylene glycol and its
ethers.
U.S. Pat. No. 4,686,260 discloses a process for preparing a polymer
emulsion for a water-based ink which contains colloidally suspended
polymer. The emulsifiers used are anionic, cationic or nonionic
emulsifiers or mixtures thereof such as a variety of alcohols and
ethylene oxide derivatives of long-chained carboxylic acids such as
lauric, myristic, palmitic, oleic and stearic acids. Also,
analogous ethylene oxide condensates of long-chained alcohols, such
as octyl, decyl, stearyl and cetyl alcohols are disclosed.
U.S. Pat. No. 4,499,255 discloses a coating composition composed of
an aqueous mixture of polyethylene and a surfactant which may be a
cationic, anionic or nonionic type. The composition can be used for
coating for baking on various electrical and automobile parts. No
nonionic surfactant was specifically identified from a chemical
standpoint except by the use of the trade name of Surfynol No. 104.
It is understood that Surfynol surfactants are proprietary mixtures
containing 2,4,7,9-tetramethyl-5-decyl-4,7-diol surfactant.
U.S. Pat. No. 3,563,910 discloses an emulsifier composition
consisting of a mixture of at least two straight and branched chain
polyoxyalkylated alcohols useful in formulating insecticides,
fungicides, defoliants and the like, as well as in the preparation
of paraffinic waxes or coatings, such as paints.
SUMMARY OF THE INVENTION
In accordance with the present invention, it has been found that an
aqueous dispersion of certain high molecular weight oxyalkylated
primary alcohols, a finely divided mostly linear aliphatic
hydrocarbon having a molecular weight of about 300-3,000 and/or
partially oxidized or similarly modified mostly linear aliphatic
hydrocarbon having a molecular weight of about 300-3,000 improves
the print characteristics of water-based inks and coating
characteristics of overprint aqueous varnishes. The water-based
inks to which the additive compositions of the present invention
are incorporated have improved adhesion, gloss, slip properties and
other desirable characteristics. The overprint aqueous varnishes to
which the additive compositions of the present invention are
incorporated impart improved properties to paper products coated
therewith.
In accordance with another aspect of the present invention, an
improved substrate, such as a film or paper product, bearing ink
indicia printed thereon is provided by overlaying such substrate
with a clear protective polymer coating having a formulation
enhancing additive comprising a mixture of certain high molecular
weight oxyalkylated primary alcohols and a finely divided mostly
linear aliphatic hydrocarbon having a molecular weight of about
300-3,000 and/or partially oxidized or similarly modified mostly
linear aliphatic hydrocarbon having a molecular weight of about
300-3,000. The coated product has improved rub resistance, slip,
water spotting prevention, water spot blocking, adhesion over
water-based inks, and clarity and other properties.
Accordingly, an object of this invention is to prepare a new and
useful water-based ink additive composition containing water, the
described oxyalkylated alcohol, and the described aliphatic
hydrocarbon and/or modified hydrocarbon. Such dispersions are
imminently suitable as ink additive systems and can be used to
significantly improve the performance of water-based inks.
Another object of the invention is to prepare a water-based ink of
improved performance, containing an ink additive composition which
includes water, the described oxyalkylated primary alcohol and the
described hydrocarbon and/or modified hydrocarbon.
Another object of the invention is to provide a method of coating a
substrate, such as a film or paper product, bearing printed ink
indicia thereon with a clear overprint aqueous varnish containing
the additive composition of the present invention. The composition
includes water, an oxyalkylated primary alcohol and a hydrocarbon
and/or modified hydrocarbon.
Another object of the invention is to provide an improved
substrate, such as a film or paper product, having printed ink
indicia thereon protected by a clear overprint paper varnish
containing the additive composition comprising the previously
described oxyalkylated primary alcohol and the previously described
hydrocarbon and/or modified hydrocarbon.
Another object of this invention is to provide a clear overprint
aqueous varnish having a formulation enhancing additive
incorporated therein, said additive comprising a finely divided
hydrocarbon and certain high molecular weight oxyalkylated primary
alcohols.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
It has been found that aqueous dispersions of a high molecular
weight oxyalkylated alcohol having an average chain length in the
hydrocarbon portion of the alcohol of from about 18 to about 150
carbon atoms, preferably from about 40 to about 90 carbon atoms,
especially about 25 to about 60 carbon atoms, and a finely divided
mostly linear aliphatic hydrocarbon having a molecular weight of
about 300-3,000 and/or partially oxidized or similarly modified
mostly linear aliphatic hydrocarbon having a molecular weight of
about 300-3,000 are useful in water-based inks and as an additive
for use in compositions protecting printed paper products and for
use in clear overprint aqueous varnishes.
The dispersants used in formulating the water-based ink additive
systems of the invention and in additive varnish compositions for
protecting a paper product bearing printed indicia are represented
by oxyalkylated alcohols of the formula: ##STR1## wherein R and
R.sub.1 individually represent hydrogen or the same or different
lower alkyl groups of from 1 to about 10 carbon atoms; R.sub.2
represents hydrogen or a methyl group; x represents a number of
from about 8 to about 75 and preferably from about 19 to about 44,
and indicates the average number of carbon atoms in the hydrocarbon
portion of the chain; and n represents the average number of
oxyalkylene groups present in the molecule and is a number of 2 to
about 65 and preferably about 4 to about 50. The most preferred
oxyalkylated alcohols are essentially linear alcohols represented
by the formula
where x and n are integers having the same values as just
mentioned. The average molecular weight of the oxyalkylated
alcohols of Formula (A) may range from about 400 to about 8,000.
The relative efficiency of the hydrophilic and lipophilic portions
of the molecular can be controlled by the addition of varying
amounts of ethylene oxide.
The dispersants are prepared by oxyalkylation of alcohols
represented by the formula: ##STR2## wherein R, R.sub.1 and x are
defined above. Oxyalkylating agents include ethylene oxide,
propylene oxide and mixtures thereof. The starting materials can be
readily oxyalkylated with the just described alkylene oxides using
typical base catalysts, such as potassium hydroxide, sodium
hydroxide, sodium ethoxide, potassium t-butoxide, sodium hydride or
sodium or potassium metals. The reaction is normally conducted
under pressures of 0 to 60 psig and at temperatures of 212.degree.
to 356.degree. F. (100.degree. to 180.degree. C.). Higher
temperatures are normally avoided to minimize side reactions and
color formation.
By varying the molecular weight of the starting alcohol and the
amount of oxyalkylation, a variety of compounds of varying
molecular weights can be prepared. Thus, the molecular weight of
the starting alcohol may be chosen to have an average molecular
weight of from about 270 to about 2,000.
A family of primary linear polymeric alcohols to be oxyalkylated
are commercially available under the trade name UNILIN.TM. alcohols
from Petrolite Corporation, Specialty Polymers Group, Tulsa,
Okla.
Also included in the aqueous dispersions of the present invention
is a finely divided mostly linear saturated aliphatic hydrocarbon
having a molecular weight of between about 300 and about 3,000.
Such hydrocarbons include various polyethylenes. The polyethylene
used in preparation of the dispersions of the present invention may
be described as having a molecular weight of about 700-3,000. The
polyethylene may be linear or may have a number of branch
formations in its molecular structure. When branched the
polyethylenes preferably have one or two branches per molecule on
the average and the branches may have 1 to 6 carbons, preferably
C.sub.1 -C.sub.6 alkyl group. For brevity the polyethylenes and
their respective molecular weights are identified by the term "PE"
followed by a number indicating the molecular weight.
In addition to the polyethylenes, the aliphatic saturated
hydrocarbon component of the dispersion of the present invention
may comprise petroleum-derived waxes, such as paraffin and
microcrystalline waxes. The paraffin waxes are mostly linear
alkanes having about 20-36 carbon atoms per molecule on the average
and a molecular weight of about 280-500 and may include C.sub.18
-C.sub.36 isoalkanes and cycloalkanes. The microcrystalline waxes
have molecular weight of about 500-700 with somewhat more branching
than the paraffin waxes.
Furthermore, the aliphatic saturated hydrocarbon component of the
dispersion of the present invention includes Fischer-Tropsch waxes.
Such waxes are polymethylenes. Polymethylene wax production is
based on the Fischer-Tropsch synthesis, which is basically the
polymerization of carbon monoxide under high pressure to produce
the wax. The polymethylene waxes useful herein preferably may have
an average molecular weight of 600-1000.
Also contemplated in the present invention are the above described
hydrocarbons which may have been chemically modified without
sacrificing the ink and/or overprint varnish enhancing properties
of the dispersions of the present invention. These include the
partially oxidized polyethylenes, polymethylenes and the
petroleum-derived waxes. The oxidized low molecular weight mostly
linear hydrocarbons of a molecular weight of 300-3,000 have
multiple functional groups, such as carboxylic acid, ketones,
alcohols, esters, etc., distributed along their chains. The
functional groups are the result of the oxidation of these
hydrocarbons by an oxygen-containing gas at elevated temperatures,
as is well known in the art.
The functional groups of the oxidized hydrocarbons may be generally
quantified by determination of an acid number which is the amount
of potassium hydroxide in milligrams required to neutralize one
gram of the oxidized polymer. The oxidized hydrocarbons will
normally have an acid number in the range of from about 5 to about
25.
Also, the polyethylenes, besides being homopolymers, may be
copolymers of ethylene with propylene, butylene, etc. and
oxygen-containing units such as vinyl acetate, acrylic acid, etc.,
as long as the ink and/or overprint varnish enhancing properties
are retained. Other closely related material that can be used
include the natural waxes, such as beeswax, carnauba and candelila
waxes.
It is important that the hydrocarbon and/or modified hydrocarbon
components of the dispersion of the present invention be finely
divided particles. For best results, these components should have
an average particle size of less than 20 microns and preferably
less than 15 microns and more than 1 micron. Such particle sizes
may be obtained by micronizing larger particles of the hydrocarbon
and/or modified hydrocarbon component or may be attained by
precipitation from solutions thereof. It is desirable that they
have a broad particle size distribution which may best be achieved
directly, for example, by precipitation, or may be achieved by
blending micronized products of different particle sizes.
One method of preparing of the aqueous dispersion of the present
invention is by the following procedure:
1. The final solids content of the dispersion which is desired is
determined. The maximum solids content attainable will vary with
the molecule weight and the amount of oxyalkylation of the
described dispersants.
2. The amount of water needed is weighted into an agitated
dispersion vessel and the amount of dispersant needed is added to a
separate container.
3. The dispersant is heated to 15.degree.-200.degree. F.
(8.degree.-11.degree. C.) above its melting point which may range
from about 180.degree.-250.degree. F. (82.degree.-121.degree. C.);
and, at the same time, the water is heated to about 190.degree. F.
(88.degree. C.).
4. When both components are heated to the appropriate temperatures,
the dispersant is slowly poured into the heated water which is at
the same time vigorously stirred.
5. When all of the dispersant has been added to the water, the heat
source is removed and stirring is continued for 2 to 3 additional
minutes.
6. The dispersion is slowly stirred, cooling at the rate of about
2.degree.-4.degree. F. (1.degree.-2.degree. C.) per minute. When
the temperature reaches about 140.degree. F. (60.degree. C.), the
cooling rate may be increased or held constant until the desired
pour temperature is reached. A stable dispersion results.
7. the finely divided hydrocarbon and/or modified hydrocarbons is
thereafter incorporated in the resulting dispersion.
The addition of a small amount of the dispersion of the present
invention in inks and overprint varnishes notably improves the
performance of such inks and varnishes in regard to gloss,
immediate adhesion, delayed adhesion, coefficient of friction
(COF), wet rub, dry rub and water resistance. Gloss can be
determined using conventional glossmeters, adhesion can be
determined by adhesive tape pull tests, slip can be determined
using conventional slide angle/slip and friction testers, rub
resistance can be determined using a Sutherland Rub Tester and
water resistance can be determined by a water drop test at 10, 30
and 60 second application intervals. These are standard tests
conventionally employed by the industry.
The preferred additive composition of the present invention is an
aqueous dispersion having a solids content of at least 8.0% by
weight. Normally, the solids content of the dispersion may be lower
or much higher in the range of at least 20% by weight and as high
as 70% by weight. Dispersions useful for adding to water-based inks
or paper protective coating compositions in accordance with the
present invention may contain about 30-92% by weight water, about
2-40% by weight oxyalkylated alcohol and about 1-60% by weight of
hydrocarbon and/or modified hydrocarbon. The amount of hydrocarbon
to modified hydrocarbon may range from 0 to 100% hydrocarbon.
Preferably, the dispersion will comprise about 40-80% by weight
water, 2-20% by weight alcohol and 1-40% by weight of hydrocarbon
and/or modified hydrocarbon.
It has been found that excellent results are obtained when mixture
of oxidized and unoxidized polyethylenes as the hydrocarbon mixture
are used. The most preferred composition is 50-85% water, 2-15%
oxyalkylated alcohol and 10-35% of oxidized plus unoxidized
polyethylene. It is preferred for the oxidized polyethylene portion
of the mixture to be about 50-95% and the unoxidized polyethylene
portion of the mixture to be about 5-50%. Excellent results have
been obtained where the composition contains 70-80% oxidized
polyethylene and 20-30% unoxidized polyethylene.
Water-based inks and paper protecting varnish compositions
containing about 0.5 to about 10% by weight of the dispersion of
the present invention have improved properties. The preferred
amount of the dispersion in the inks is about 1-8% by weight.
The additive formulation of the present invention may be
incorporated in conventional clear overprint aqueous varnishes
containing a polymer and a solvent system. Typically, the polymer
may be a styrene/acrylic copolymer. Any polymer suitable for use in
clear overprint aqueous varnishes are useful.
In the following examples, all percentages are on a weight/weight
basis unless otherwise indicated.
The following examples will illustrate the practice of the present
invention in its preferred embodiments. Other embodiments within
the scope of the claims herein will be apparent to one skilled in
the art from consideration of the specification and practice of the
invention as disclosed herein. It is intended that the
specification, together with the examples, be considered exemplary
only, with the scope and spirit of the invention being indicated by
the claims which follow.
EXAMPLE I
This example illustrates preparation of the oxyalkylated alcohol
component which serves as the dispersant of the composition of the
present invention.
A primary linear alcohol of the following formula was prepared by
oxidation of a corresponding polyethylene precursor:
wherein x is about 23.
This olefin-derived linear polymeric alcohol was oxyethylated in a
conventional manner to provide an oxyethylated alcohol having 16
ethylene oxide units per mole of polymer on the average and a
molecular weight of about 1,400 and melting about 224.degree.
C.).
EXAMPLE II
This example illustrates the preparation of an aqueous dispersion
of the oxyethylated alcohol prepared in Example I.
Using the formulating procedure as described above, a suitable
quantity of water was heated to 190.degree. F. (88.degree. C.). In
a separate vessel the alcohol was heated to a molten condition.
Then, molten oxyethylated alcohol was added to the hot water under
high shear conditions to yield a 25% by weight aqueous dispersion
of the oxyethylated alcohol and cooled. This dispersion was
designated Composition 1.
EXAMPLE III
This example illustrates the preparation of the micronized low
molecular weight polyethylenes.
Linear polyethylene of an average molecular weight of about 2,000
was used in the following examples. Oxidized polyethylene used in
the following examples was prepared by air oxidizing a linear
polyethylene of a molecular weight of 1,500 to an acid number of
18. The unoxidized polyethylene portion and the oxidized
polyethylene portion separately were comminuted using conventional
micronizing equipment. Portions of each polyethylene were
comminuted to average sizes of 6 microns and 10 microns.
EXAMPLE IV
This example illustrates the preparation of an aqueous dispersion
containing the oxyethylated alcohol and a mixture of oxidized and
unoxidized micronized low molecular weight linear
polyethylenes.
To 100 parts by weight of the aqueous dispersion prepared in
accordance with Example II, 1.9 parts by weight of the oxidized
polyethylene (MW=1,500) and 0.6 parts by weight of the unoxidized
polyethylene (MW=2,000) were added and vigorously blended into the
dispersion. The unoxidized polyethylene had an average size of 10
microns and the oxidized polyethylene had an average size of 6
microns. The resulting composition was given the designation of
Composition 2.
EXAMPLE V
In this example, an aqueous dispersion was prepared by mixing at a
temperature of 250.degree. F. (121.degree. C.) under pressure
water, the oxyalkylated alcohol of Example I and unoxidized linear
polyethylene wax having a molecular weight of 2,000 to produce a
dispersion composed of 60% by weight water, 19% by weight
oxyalkylated alcohol and 21% by weight polyethylene. Upon cooling
the polyethylene precipitated as finely divided particles having an
average size of 2 microns. The resulting dispersion was designated
Composition 3.
EXAMPLE VI
In this example, a dispersion of 60% water and 40% solids was
prepared. Of the solids 80% was composed of the oxyalkylated
alcohol of Example I and 10% by weight of oxidized polyethylene
(MW=1,500) having a 6 micron size and 10% by weight of unoxidized
polyethylene (MW=2,000) having a 10 micron size was prepared. The
resulting dispersion was designated Composition 4.
EXAMPLE VII
This example illustrates the preparation of a water-based ink.
The following ink composition was prepared:
TABLE 1 ______________________________________ Ingredient Weight %
Supplier ______________________________________ Joncryl 61-LV 13.0
S. C. Johnson Water 2.5 -- Isopropanol (95%) 4.5 -- Foamburst 320CT
1.0 Ross Chemical Neocryl A-1054 55.0 ICI Resins Flexiverse BCD5103
24.0 Sun Chemical ______________________________________
This preparation was accomplished by weighing Joncryl 61LV acrylic
emulsion and water into a mixing tub. Then, Foamburst 320CT
antifoam, isopropanol and Neocryl A-1054 acrylic resin dispersion
were added to the tub and mixed thoroughly with the other
ingredients therein. Finally, the Flexiverse BCD5103 blue pigment
was added to the tube and mixed thoroughly with the ingredients
therein to form a well dispersed ink composition. This ink
composition was blended with ink additive compositions as described
in Example VIII.
EXAMPLE VIII
Water-based blue surface inks containing compositions of the
present invention were applied to various substrates at different
levels of compositions based on oxyethylated alcohols and the
micronized polyethylene polymers of low molecular weight and were
tested for gloss, 90.degree. degree delayed adhesion, static
coefficient of friction (slide angle) and dynamic coefficient of
friction (slide angle) using a four color, flexographic press.
Composition 5 was an aqueous dispersion of Example II containing a
surfactant coated micronized branched polyethylene of about 700
molecular weight.
Higher gloss readings and higher adhesions are desirable properties
and lower coefficients of friction are also desirable properties in
the following table.
TABLE 2 ______________________________________ Gloss on Low Density
Polyethylene Substrate Ink Ink Glossmeter Additive Additive %
Reading ______________________________________ Composition 2 3 77
Composition 2 6 76 Composition 3 1.25 80 Composition 3 3.75 74
Composition 5 5 80 ______________________________________
TABLE 3 ______________________________________ Gloss on
Polypropylene Film Ink Ink Glossmeter Additive Additive % Reading
______________________________________ Composition 2 3 87
Composition 2 6 79 Composition 3 1.25 86 Composition 3 3.75 68
Composition 5 5 80 ______________________________________
TABLE 4 ______________________________________ 90.degree. Delayed
Adhesion on Low Density Polyetheylene Substrate Ink Ink Additive
Additive % Rating ______________________________________
Composition 2 3 10.0 Composition 3 6 10.0 Composition 3 1.25 9.0
Composition 3 3.75 7.5 Composition 5 5 8.0
______________________________________
TABLE 5 ______________________________________ 90.degree. Delayed
Adhesion on Polypropylene Film Ink Ink Additive Additive 5 Rating
______________________________________ Composition 2 3 1.0
Composition 2 6 10.0 Composition 3 1.25 4.5 Composition 3 3.75 8.0
Composition 5 5 6.5 ______________________________________
TABLE 6 ______________________________________ Static COF* on Low
Density Polyethylene Substrate Ink Ink Additive Additive % COF
______________________________________ Composition 2 3 0.43
Composition 2 6 0.49 Composition 3 1.25 0.48 Composition 3 3.75
0.47 Composition 5 5 0.47 ______________________________________
*Coefficient of Friction as measured using slide angle test
employing Testing Machines, Inc., Model No. 3235-00.
TABLE 7 ______________________________________ Static COF on
Polypropylene Film Ink Ink Additive Additive % COF
______________________________________ Composition 2 3 0.58
Composition 2 6 0.57 Composition 3 1.25 0.59 Composition 3 3.75
0.50 Composition 5 5 0.47
______________________________________
TABLE 8 ______________________________________ Dynamic COF on Low
Density Polyethylene Substrate Ink Ink Additive Additive % COF
______________________________________ Composition 2 3 0.31
Composition 2 6 0.34 Composition 3 1.25 0.32 Composition 3 3.75
0.37 Composition 5 5 0.34
______________________________________
TABLE 9 ______________________________________ Static COF on
Polypropylene Film Ink Ink Additive Additive % COF
______________________________________ Composition 2 3 0.35
Composition 2 6 0.33 Composition 3 1.25 0.38 Composition 3 3.75
0.26 Composition 5 5 0.31
______________________________________
In this example, the speed of the printer was held constant at 200
feet/minute and each run was about a minute long. The wet
temperature on the drier was held at 170.degree. F. (77.degree. C.)
for all the runs. This example shows that the water-based printing
aid compositions of the present invention are useful in the
formulation of water-based inks.
EXAMPLE IX
This example illustrates the results of using compositions of the
present invention wherein different combinations of unoxidized
polyethylene and oxidized polyethylene in different finely divided
sizes were employed.
In each of the following compositions various linear polyethylene
species were added to an aqueous dispersion prepared in accordance
with Example II. The total amount of added polyethylene was 2.5% by
weight of the resulting composition.
The first species of polyethylene was a mixture of 50% unoxidized
polyethylene of 2,000 molecular weight and a particle size of 6
microns and 50% unoxidized polyethylene of 2,000 molecular weight
and a particle size of 10 microns.
The second species of polyethylene was a mixture of 50% by weight
oxidized polyethylene of 1,500 molecular weight and a particle size
of 6 microns and 50% by weight of oxidized polyethylene of 1,500
molecular weight and a particle size of 10 microns.
The third species of polyethylene was a mixture of 50% by weight of
unoxidized polyethylene of 2,000 molecular weight and a particle
size of 6 microns and 50% by weight oxidized polyethylene of 1,500
molecular weight and a particle size of 10 microns.
The fourth species of polyethylene was a mixture of 50% by weight
of oxidized polyethylene of 1,500 molecular weight and particle
size of 6 microns and 50% by weight of unoxidized polyethylene of
2,000 molecular weight and a particle size of 10 microns.
The fifth species of polyethylene was a mixture of 50% by weight of
unoxidized polyethylene (MW=700; 6 micron size) and 50%
polyethylene added as a 30% solids aqueous dispersion by weight of
a commercially available aqueous dispersion of polyethylene (30%
solids). This fifth species was not made in accordance with Example
II mentioned above; it is a stand alone product.
The sixth species of polyethylene was a mixture of 75% by weight of
oxidized polyethylene of 1,500 molecular weight and a particle size
of 6 microns and 25% by weight of unoxidized polyethylene of 2,000
molecular weight and a particle size of 10 microns.
The compositions of the various species of polyethylene mixtures
and the oxyethylated alcohol of the present example were added to a
standard water-based blue ink in an amount of 3.0% by weight. The
resulting ink composition was applied to aluminum foil and
polypropylene film and tested for various properties including
gloss, slip, rub and adhesion. The results of such tests are
summarized in Tables 10 and 11.
TABLE 10 ______________________________________ Comparision on
Aluminum Foil Adhesion Composition Gloss Slip Rub Ranking
______________________________________ PE Species 1 77 .41/.21 .09
2 PE Species 2 72 .42/.19 .07 6 PE Species 3 73 .36/.20 .07 2 PE
Species 4 73 .38/.20 .07 2 PE Species 5 71 .44/.23 .08 5 PE Species
6 79 .42/.18 .05 1 ______________________________________
TABLE 11 ______________________________________ Comparison on
Polypropylene Film Adhesion Composition Gloss Slip Rub Ranking
______________________________________ PE Species 1 71 .44/.23 .08
2 PE Species 2 68 .39/.20 .06 6 PE Species 3 66 .45/.20 .07 2 PE
Species 4 68 .43/.20 .07 2 PE Species 5 62 .48/.21 .07 5 PE Species
6 65 .39/.15 .06 1 ______________________________________
From the Tables 10 and 11, it is noted that the combination of the
use of oxidized polyethylene of 6 micron size and unoxidized
polyethylene of 10 micron size when added to the aqueous dispersion
of oxyethylated alcohol provides markedly better gloss, slip and
adhesion in water-based inks as compared to the use of the standard
additive when added to the same dispersion and slightly better
properties over other tested combinations of oxidized and
unoxidized polyethylenes.
EXAMPLE X
A second oxyethylated alcohol having a molecular weight of about
865 and an ethylene oxide content of 10 moles per mole of polymer
was prepared.
EXAMPLE XI
In this example, an aqueous dispersion containing a mixture of
paraffin wax and essentially linear unmodified polyethylene was
prepared to form a 50% solids composition. Of the solids 10% by
weight was composed of the oxyalkylated alcohol of Example X and
90% by weight of paraffin wax (MP=147.degree. F. (63.9.degree.
C.)). The dispersion was added to printing ink at an additive level
of 3.0% by weight. The resulting ink when applied to various
surfaces showed improved characteristics.
When used in small amounts by weight of the ink composition in
water-based inks, the aqueous dispersions prepared in accordance
with this example improve such inks in terms of gloss maintenance
and rub resistance without sacrifice of adhesion of the inks to a
substrate, of slip of the inks from the substrate and of water spot
resistance of inks applied to a variety of substrates.
EXAMPLE XII
This example illustrates the improvements in the finely divided
polyethylene in water using the long chain oxyalkylated alcohol
dispersants as compared to the use of other tested nonionic
surfactants.
In various tests the use of long chain oxyalkylated alcohol
dispersants as used in the present invention was compared with the
use of other nonionic dispersants with regard to the ability of
each to form stable dispersions of finely divided polyethylene
having a molecular weight of 500 (PE-500).
The dispersants tested as follows:
______________________________________ Surfactant Description
______________________________________ a The oxyalkylated alcohol
prepared generally in accordance with Example I of the instant
application but having an average molecular weight of 900 and 10
ethylene oxide units b T Max 81, Mazer, Inc. HLB 10.0
(POE-5-sorbitan monostearate) c T Max 61, Mazer, Inc., HLB 9.6
(POE-5-sorbitan monostearate) d Tween 81, ICI Americas, Inc., HLB
10.0 (POE-S-sorbitan oleate) e Tween 61, ICI Americas, Inc. HLB 9.6
(POE-4-sorbitan monostearate) f Brig 30, ICI Americas, Inc., HLB
(POE-4-lauryl ether) g Hodag 20-LT, Hodag Inc., HLB 10.0
(PEG-200-monolaurate) h Hodag 40-LT, Hodag Inc., HLB 12.8 (PEG-400
monolaurate) i Triton N-57, Rohm-Haas, HLB 10.0 (nonylphenol + 5EO)
j Surfynol 104-E, Air Products Co.,
(2,4,7,9-tetramethyl-5-decyl-4,7-diol)
______________________________________
Dispersing of PE-500 were made by melting various amounts of PE-500
and various amounts of the tested surfactants by heating and
stirring the PE-500 and surfactants together to about 225.degree.
C. Then, each of the resulting melts was poured into various
amounts of water at 200.degree. F. with vigorous stirring. While
still being stirred, each of the resulting aqueous dispersions was
quickly cooled to room temperature. Then, the stability of each
dispersion was visually noted. The results of these tests have been
set forth in the following table wherein the weights of the
components are given in grams:
______________________________________ Wt. of Surfac- Surfac- Wt.
of Wt. of tant tant H.sub.2 O PE-500 Observation
______________________________________ a 5 450 45 White stable
dispersion of extremely fine particles b 5 450 45 White dispersion
with quick separation of particles c 5 450 45 White dispersion with
quick separation of particles d 5 450 45 White dispersion with
quick separation of particles e 5 450 45 White dispersion with
quick separation of particles f 5 450 45 White dispersion with some
large particles and with quick separation of particles g 5 450 45
White dispersion with quick separation of particles h 5 450 45
White dispersion with many large particles and quick separation of
particles i 5 450 45 White dispersion with many large particles and
quick separation of particles j 5 450 45 White dispersion with
quick separation of particles b 10 450 40 White dispersion with
quick separation of particles b 15 450 35 White dispersions with
many large particles and quick separation of particles b 20 450 30
White dispersion of small particles and quick separation of
particles e 15 450 35 White dispersion with many large particles
and quick separation of particles
______________________________________
From the above data, it can be seen that the stability of aqueous
dispersions of polyethylene of low molecular weight is greater when
the dispersants used in the ink composition of the present
invention is used as compared to the use of other tested nonionic
surfactants.
EXAMPLE XIII
Various compositions of the present invention were tested as
property enhancing additives in clear overprint aqueous varnishes
conventionally used to protect paper products having ink indicia
printed thereon. In the test, 8.times.51/2 inch paper cards
obtained from the Leneta Company were employed. One half of each
card was blank and the other half had black lithographic ink
printed on it. The cards had a very light coating of lacquer on
both the blank portion and the black portion.
To a standard overprint varnish, additives of the present invention
were incorporated in a series of tests and a standard additive
presently in use in the industry was incorporated in a comparative
test. The enhancement of the tested varnishes in terms of gloss,
rub resistance and slip angle slide was determined using
conventional and known procedures.
In each of the tests the standard overprint protecting varnish had
the following composition as set forth in Table 12:
TABLE 12 ______________________________________ Parts/hundred
Ingredient (pph) ______________________________________
Styrene/acrylic copolymer 90 Surfynol 104-E emulsifier 0.3 Water
9.7 ______________________________________
The effectiveness of the additive compositions of the present
invention in enhancing the properties of the just described clear
overprint aqueous paper varnish as compared to the effectiveness of
a standard additive conventionally used in the trade to assist
formulators of clear paper coating systems as above described was
determined. In all the tests the black portion of the cards was
used as surface on which the properties were determined.
The standard additive known as Jonwax 26 and obtained from S.C.
Johnson Co. is identified as a 25% solid aqueous dispersion of
polyethylene wax containing 6% fatty acid soap as the
dispersant.
Additive Composition 6 was composed of 21% polyethylene of 2,000
molecular weight (PE-2000), 19% of the oxyethylated alcohol
dispersant of Formula B above where x averages 49 and n averages
16, and 60% water.
Additive composition 7 was composed of 1.8% oxidized PE-1500, 0.6%
unoxidized PE-2000, 24% of the oxyethylated alcohol dispersant of
Formula B above where x averages 49 and n averages 16, and 73.6%
water.
Additive Composition 8 was composed of 45% of a paraffin wax (Citco
Pacemaker 53), 5% of the oxyethylated alcohol dispersant of Formula
B above where x averages 29 and n averages 10, and 50% water.
Additive Composition 9 was composed of 50% of Composition 8 and 50%
of Composition 3.
The test data of the various tests have been tabulated in Table
13:
TABLE 13 ______________________________________ Slide Angle Rub
Resistance Slide Angle Dynamic Relative Rating Static Slip Slip
Additive % (0-4 best) Resistance Resistance Gloss
______________________________________ Blank 0.0 0.0 34 32 68
Standard 6.0 1.0 23 16 70 No. 6 3.8 4.0 23 14 65 No. 7 6.0 2.0 24
13 68 No. 8 3.0 3.6 14 9 72 No. 9 3.3 4.0 16 9 68
______________________________________
As can be seen from the above table, the additives of the present
invention consistently provide better relative rub resistance even
at lower amounts as compared to the use of the standard additive.
Improvements are also noted in both static slip resistance and
dynamic slip resistance with the use of the additives of the
present invention without sacrifice of gloss.
While the illustrative embodiments of the invention have been
described with particularity, it will be understood that various
other modifications will be apparent to and can be readily made by
those skilled in the art without departing from the spirit and
scope of the invention. Accordingly, it is not intended that the
scope of the claims appended hereto be limited to the examples and
descriptions set forth herein but rather that the claims be
construed as encompassing all the features of patentable novelty
which reside in the present invention as herein disclosed,
including all features which would be regarded as equivalents
thereof by those skilled in the art to which the present invention
pertains.
* * * * *