Note: Descriptions are shown in the official language in which they were submitted.
CA 02344404 2001-03-15
WO 00/20219 _ PCTNS99/23150
METHOD OF FORMING INDICIA ON A GAME BALL
SURFACE USING AN INK JET PRINTER
Related Applications
This application is a continuation-in-part of U.S. Application No.
09/166,970 filed October 6, 1998, currently pending, which is a continuation-
in-
part of U.S. Application No. 08/877,938 filed June 18, 1997, now U.S. Patent
No. 5,885,173, which in turn is a continuation-in-part of U.S. Application No.
08/529,361, now U.S. Patent No. 5,770,325. U.S. Application No.
09/166,970 is also a continuation-in-part of U.S. Application No. 08/753,704
filed November 27, 1996, now U.S. Patent No. 5,827,134. Each of the
foregoing applications and patents is incorporated by reference herein.
Background of the Invention
The present invention generally relates to ink jet printing on curved
surfaces, and more particularly to ink jet printing on game balls. Inks that
are
used in ink jet printing commonly are water-based resins which contain dye as
a coloring agent. Other types of inks, such as solvent-based (i.e., non-
aqueous)
formulations and ultraviolet ("UV") curable inks, could be useful in ink jet
printing
if an appropriate viscosity and surface tension of the ink could be achieved
as to
be compatible with both the ink jet printing system and the game ball surface.
UV curable inks are quick-curing inks and therefore are advantageous for
in continuous-type processes in which subsequent treatment of an ink-printed
substrate is involved. A number of UV curable inks are known. For example,
U.S. Patent No. 4,271,258 discloses a photopolymerizable ink composition
containing acrylate resin, rnethacrylate monomer or oligomer, acryfate monomer
or oligomer, photoinitiator, and a particular type of an epoxy resin. U.S.
Patent
No. 5,391,685 discloses a UV curable ink having an isocyanate compound added
thereto. U.S. Patent No. 5,391,685 contends that the ink disclosed therein is
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-2_
particularly well suited for printing on slightly adhesive plastic bases, such
as
those made of polyoxymethylenes and polypropylenes.
Screen printing on spherical surfaces such as golf balls can be difficult.
As a result, pad printing customarily is used for marking golf ball surfaces.
However, many of the known UV curable inks are not well suited for pad
printing
due to difficulties in transferring the ink from a pad to a substrate.
Furthermore,
UV curable inks that can be pad printed have not been found suitable for use
on
golf balls. More specifically, when applied to a golf ball, these inks are not
sufficiently durable (impact resistant) to withstand multiple blows by a golf
club.
it would be useful to obtain a highly durable UV curable ink which has
favorable
pad transfer properties when used for printing indicia on surfaces such as a
curved and dimpled surface of a golf ball, and which provides an image having
good durability.
Ink jet printing is commonly used to form multicolor images on paper for
use in advertising materials, computer-generated photographs, etc. There are
two fundamental types of ink jet printing: continuous and drop on demand. U.S.
Patent No. 5,623,001 describes the distinction between continuous and drop on
demand ink jet printing. In continuous ink jet printing, a stream of ink drops
is
electrically charged and then deflected by an electrical field either directly
or
indirectly onto the substrate. In drop on demand ink jet printing, the ink
supply
is regulated by an actuator such as a piezoelectric actuator. The pressure
produced by the actuation forces a droplet through a nozzle or nozzles onto
the
substrate.
It is known to print directly on a game ball surface using a continuous ink
jet printer which relies on an electric charge to deliver droplets of ink to
the game
ball surface. (See JP 8322967-A published December 10, 1996 (Bridgestone)
and JP 2128774-A published May 17, 1990 (Bridgestone)).
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-3-
Summary of the Invention
An object of the invention is to provide a new and improved method of
forming durable images on game balls.
Another object of the invention is to provide a method of forming multi-
color images on game balls.
A further object of the invention is to provide a method of quickly and
efficiently transferring a logo or image from a computer screen to a game ball
surface.
Another object of the invention is to provide a game ball, such as a golf
ball, having a clear and durable ink image printed thereon. Another object
of the invention is to provide a method for printing indicia on a hard surface
of
a game ball, the indicia comprising ink jet printable ink.
Yet another object of the invention is to provide a method for applying
smudge resistant and durable indicia to a visible surface of a game ball.
Other objects of the invention will be in part obvious and in part pointed
out more in detail hereafter. The present invention satisfies at least one of
the
foregoing objects, at least in part.
One aspect of the invention is a method of applying indicia to a game ball,
comprising: (a). obtaining an ink composition suitable for use in ink jet
printing,
(b), dispensing the ink composition in the form of indicia on a transfer
medium
using an ink jet printer, and (c1. transferring the indicia from the transfer
medium
to the surface of a game ball.
The transfer medium comprises at least one member selected from the
group consisting of silicone, fluoropolymer, and polypropylene. The transfer
medium can be a low surface energy material.
In one form of the invention, the ink composition contains a polymer resin.
In another form of the invention, the ink composition contains resin
components.
The game ball can be a golf ball. The golf ball usually has a dimpled
surface.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99I23150
-4-
An alternative method further includes: (d). forming a protective coating
over the indicia on the surface of the game ball. The protective coating can
include a polyurethane.
The method of the invention optionally includes forming a primer coating
layer on at least a portion of the surface of game ball prior to (b). The
primer
coating layer can contain a material which promotes at least one of
absorption,
adhesion and clarity of the indicia. Several examples of this material are
talc,
amorphous silica, bentonite clay, magnesium silicate, or combinations of these
materials.
The transfer medium used in the method of the invention can be a
silicone-containing medium such as a sheet or a pad.
fn one form of the invention, the ink composition is an aqueous-based
formulation. In another form of the invention, the ink composition is a non-
aqueous, or solvent-based, formulation. In another alternative form of the
invention, the ink comprises a UV curable resin, and the method further
comprises: (e). curing the indicia after the indicia have been transferred
onto the
game ball surface.
Another aspect of the invention is a method of applying indicia to a game
ball, comprising: (a). obtaining an ink composition suitable for use in ink
jet
printing, (b). forming an indicia receiving layer on at least a portion of the
game
ball surface, the indicia receiving layer containing a material which promotes
absorption, adhesion or clarity of the indicia, and (c). printing indicia on
the
indicia receiving layer using an ink jet printer. Optionally, the method
further
includes: (d). forming a protective coating over the indicia. The indicia may
have
impact resistance sufficient to render the game ball suitable for use in
competitive play.
One example of a suitable game ball is a golf ball. The indicia receiving
layer optionally comprises a polyurethane.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-5-
The material which promotes absorption, adhesion or clarity of the indicia
can be talc, amorphous silica, bentonite clay, magnesium silicate, or
combinations thereof.
The indicia can be printed directly on the game ball surface using the ink
jet printer. Alternatively, the indicia can be printed on a transfer medium
using
the ink jet printer, and can be subsequently transferred to the surface of the
indicia receiving layer of the game ball. A drop-on-demand ink jet printer can
be
used. It can have a piezo crystal or thermal printhead.
In another optional form of the invention, the ink comprises an UV curable
resin, and the method further comprises: (e). curing the indicia after the
indicia
have been printed on the indicia receiving layer.
Another aspect of the invention is a method of applying indicia to a game
ball, such as a golf ball, comprising: (a). obtaining a UV curable ink
composition
suitable for use in ink jet printing, (b). printing indicia on a surface of
the game
ball using an ink jet printer, and (c). curing the UV ink composition. The
method
can further include: (d). forming a protective coating over the indicia.
Another aspect of the invention is a method of applying indicia to a game
ball, such as a golf ball, comprising: (a). obtaining an ink composition
suitable for
use in ink jet printing, (b). printing indicia on the surface of a game ball
using a
drop-on-demand ink jet printer, and (cl. forming a protective coating over the
indicia. The resolution of the indicia may be at least about 300 dots per inch
("d.p.i.") (about 120 dots per cm), optionally at feast about 500 d.p.i.
(about
200 dots per cm), optionally at least about 600 d.p.i. (about 240 dots per
cm),
optionally at least about 1000 d.p.i. (about 390 dots per cm).
CA 02344404 2001-03-15
WO 00/20219 PCTNS99/23150
-6-
Brief Description of the Drawing
Figure 1 depicts a golf ball having indicia comprising ink jet printable ink
in accordance with the present invention.
Figure 2 is a flow chart depicting two methods for applying ink jet
printable indicia to a game ball by indirect transfer.
Figure 3 is a flow chart depicting a method for applying ink jet printable
indicia to a game ball using a direct printing method.
Figure 4 schematically depicts the durability test apparatus to determine
the durability of the indicia of the invention on a golf ball.
Figure 5 is a partial side view of a portion of an insert plate in the
durability test apparatus which has grooves intended to simulate a golf club
face.
Figure 6 depicts differences in pad transfer of four UV curable inks.
Figure 7 depicts a method for applying indicia to a game ball via a logo
stamping machine using ink jet printed ink.
Figure 8 depicts a golf baff with indicia imprinted by custom stamping -
by pad printing using a conventional solvent-borne pad printable ink - after
being
subjected to the wet barrel durability test.
Figure 9 depicts a golf ball with an indicia imprinted by an ink jet printer
using solvent-based (non-aqueous? ink after being subjected to the wet barrel
durability test.
Figure 10 depicts the adaptations made to the drive system of an ink jet
printer to allow for accommodation of a game ball.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
_'_
Detailed Description of the Invention
One method of the invention for forming an image on a game ball using
ink jet printing is an indirect printing technique which involves printing
indicia on
a transfer medium using an ink jet printer and then transferring the image
from
the transfer medium to the game ball surface. Another method of the invention
is to print directly on a specially treated surface of a game ball using an
ink jet
printer.
A golf ball formed according to one embodiment of the present invention
is shown in Figure 1. The golf ball 8 has a central core 10, which can be
solid,
liquid, gas, gel, wound, or a combination of these, and a dimpled cover 12
surrounding the core. Indicia 14 formed from an ink jet printable ink are
formed
over the cover 12. Optionally, an indicia receiving layer 15 is positioned
between the indicia 14 and the cover 12. A protective top coat 16 is formed
over the indicia 14. This top coat 16 may cover the entire ball 8, though a
partial topcoat 16 covering only a somewhat larger area than the indicia 14 is
also contemplated.
Two methods of indirectly ink jet printing on a golf ball surface are
depicted in Figure 2. As shown at 30, a golf ball is primed with an ink
retaining
primer. An image is ink jet printed onto a transfer sheet, as shown at 32, or
transfer pad, as shown at 34. if the image is printed onto a transfer sheet,
it is
then transferred to a transfer pad on a stamping machine at 34'. The transfer
pad, which is configured for printing on the surface of a golf ball,
subsequently
stamps the image on a golf ball surface at 36. After the image is applied, the
surface of the ball and the indicia optionally can be coated with a suitable
top
coat at 38.
A method for directly ink jet printing on a golf ball is shown in Figure 3.
As shown at 40, a golf ball is primed with an ink retaining primer. After the
coating has been applied, an image is ink jet printed directly onto the
surface of
CA 02344404 2001-03-15
WO 00/20219 PCT/IJS99/23150
_g_
the primer at 42. After the image has been applied, the surface of the ball
and
the indicia optionally can be coated with a suitable top coat at 44.
The method of the invention can be used on curved surfaces of game balls
such as golf balls, basketballs, baseballs, softballs, and the like, and is
particularly useful on golf balls. It can be difficult to print on the curved
and
dimpled surface of a golf ball because the dimples tend to distort an image
printed thereon and because the plastic cover of a golf ball, which typically
is
made of ionomer, bafata, or polyurethane, has a low surface energy. The low
surface energy of the ionomer cover makes adhesion difficult and also causes
ink
to form into beads when placed on the cover, thereby blurring the printed
image.
One way in which the present invention overcomes the beading problem is by
applying a primer coat to at least the portion of the ball surface upon which
the
indicia are to be printed, the primer coat containing a material which
promotes
absorption, adhesion, and/or clarity of the indicia. Suitable materials of
this type
to use in the primer coat of a game ball such as a golf ball include talc,
amorphous silica, bentonite clay, magnesium silicate, or the like, or a
combination of these.
In another form of the invention, the material which promotes absorption,
adhesion, and/or clarity of the indicia is incorporated into the cover itself.
When
the cover is formed from ionomer, polyurethane or balata, for example,
suitable
materials of this type which can be incorporated therein include talc,
amorphous
silica, bentonite clay, magnesium silicate, or the like, or a combination of
these.
The ink which is used in the method of the invention is one which is
suitable for use in an ink jet printer. Typically, the ink contains a coloring
agent,
a carrier, and additives. The coloring agent usually is a dye and/or pigment
and
can be fluorescent. Alternately, the ink can contain a fluorescent material as
the
coloring agent instead of or in addition to an ordinary dye. As another
alternative, the ink can contain a selective absorber of infrared or microwave
radiation. The carrier or vehicle for the coloring agent may be water or an
organic solvent. The physical characteristics of the substrate and the other
ink
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
_g_
components determine the type and quantity of carrier to be used. Examples of
useful additives include materials to control pH, viscosity, light fade and
surface
tension. Furthermore, the ink can contain a polymer resin or resin components.
Examples of polymer resins or resin components which are used in conventional
ink jet printing inks include polyurethanes, polyesters, polyketones and
polyacrylates. In the case of a UV curable ink, the resin components could be,
for example, oligomers. The ink composition and the composition of the ball
cover or primer layer to which the indicia are to be applied may be selected
such
that the surface tension of the ink is appropriately related to the surface
properties of the substrate to which it is to be adhered. Inks contemplated to
be
suitable for ink jet printing typically have a viscosity of from about 1 to
about 20
cps measured at the temperature of application.
As indicated above, UV curable inks can be used in accordance with the
method of the present invention. Most commercially available UV inks are not
suitable for ink jet printing due to the high concentration and size of the
pigments
and fillers in these formulations. To facilitate flow through the ink jet
printer, a
UV ink suitable for an ink jet printer should incorporate very finely divided
pigments (about 0.1 micron or alternatively less than 100 Angstroms),
dissolved
dyes, or combinations of dyes and finely divided pigments. Flow additives,
surface tension modifiers, extra solvent, etc. may be added to the ink formula
to improve ink jet printability and prevent clogging of the ink jet printer.
UV
curable inks are described below in further detail in a separate section of
this
document.
if a primer coating layer is applied to a game ball cover, the coating
typically is a solvent-borne or water-borne polyurethane material. Non-
limiting
examples of suitable coatings are described in detail in commonly assigned
U.S.
Patent Nos. 5,409,233, 5,459,220 and 5,494,291, the contents of which are
incorporated herein by reference.
It is useful for a top coat to be applied over the indicia to protect the
indicia unless the indicia have sufficient adhesion to the surface to which
they
CA 02344404 2001-03-15
WO 00/20219 PCTNS99/23150
-10-
are applied, e.g., the cover or a primer layer, to render the use of a top
coat
unnecessary. The adhesion between the ink and the top coat and/or substrate
is contemplated to be sufficiently strong so that the indicia remain
substantially
intact when the game ball is used. Standards for image retention vary
depending
upon the intended use of the game ball and the degree and frequency of impact
that the image is required to withstand. When applied to a golf ball, the ink
durability desirably is sufficient that after the ball is subjected to the wet
barrel
durability test procedure described below, at feast about 50% of the surface
area
of the original image remains, optionally at least about 70%, optionally at
least
about 80%. Excellent durability results when more than about 85% of the
image remains.
As indicated above, in one embodiment of the invention, the indicia are
printed onto a transfer medium using an ink jet printer and are subsequently
transferred to the game ball surface. A suitable transfer medium is one which
has a surface that allows for good clarity of the indicia printed thereon
while
providing for transfer of the image onto the game ball surface. One
contemplated transfer medium is a silicone pad. If necessary, an absorptive
filler
can be added to the silicone pad to promote flow-out of the ink, and to
prevent
beading on the surface of the silicone pad. Additionally or alternatively, the
surface of the pad can be roughened to an extent necessary to achieve the
desired surface energy. When the image is to ne pnniea on a curv~U amu
dimpled surface of a golf ball, using a pad rather than a flat sheet for the
transfer
substrate may facilitate the application of ink inside the dimples. One
contemplated type of silicone pad is that which is used in conventional golf
ball
pad printing.
Although any ink jet printer may be used, two types of ink jet printers
specifically contemplated for printing on game balls are continuous ink jet
printers and drop on demand ink jet printers. In a continuous ink jet printer,
a
stream of ink drops is electrically charged and then deflected by an
electronic
field either directly or indirectly onto the substrate. In a drop on demand
ink jet
CA 02344404 2001-03-15
WO 00/20219 PCT/EJS99/23150
-1 1-
printer, the ink supply is regulated by an actuator such as a piezoelectric
actuator. The pressure produced by the actuation forces a droplet through a
nozzle or nozzles onto the substrate.
UV curable inks
The UV curable ink of the present invention can be used for printing
indicia on golf balls, softballs, baseballs, other game balls, as well as
other
sporting goods including, but not limited to, softball and baseball bats,
tennis and
racquetball rackets, and golf clubs. The ink also can be applied to a variety
of
materials including, but not limited to, ionomers, polybutadiene, composite
materials, metals, etc.
As indicated above, the ink comprises a UV curable resin, a coloring
agent, such as a pigment or a dye, one or more photoinitiators, and possibly a
solvent. The ink may also include aluminum trihydroxide. A thinning agent that
includes a monomer and/or a solvent can be added. A wetting agent also can
be included.
The UV curable resin may comprise an oligomer. Non-limiting examples
of the oligomer include one or more epoxies, acrylics, acrylate urethanes,
elastomeric acrylates, unsaturated polyesters, and polyethers. Specific
examples of suitable ofigomers include methacrylates such as bisphenol A
ethoxylate dimethacrylate and acrylated epoxies. Blends of different oligomers
can be used. The oligomer can provide the ink with characteristics of
flexibility
and impact resistance that are sufficient to withstand the conditions to which
the substrate is to be subjected. For example, if the substrate is a golf
ball, the
oligomer may impart to the ink more flexibility than is inherent in the
underlying
substrate, which is contemplated to provide good durability. When a top coat
is
to be placed over the ink, the ink desirably is not so highly cross-linked
that
adhesion of the top coat to the ink is substantially hindered.
The uncured ink can comprise about 10 - 90 wt % oligomer, optionally
about 20 - 80 wt % oligomer, optionally about 50 - 70 wt % oligomer.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-12-
The coloring agent can be any type of pigment, dye or the like which will
withstand UV treatment, i.e., which is not UV labile. Furthermore, the
coloring
agent is contemplated to permit sufficient passage of UV light through the
ink,
by any combination of transmission, reflection, or refraction mechanisms, to
initiate photocrosslinking. Liquids or powders can be used. One non-limiting
example of an ink is a powder which is dispersed in a liquid monomer. Carbon
black and iron oxide black are non-limiting examples of suitable pigments for
making black inks. Red lake and quinacrydones are non-limiting examples of
suitable pigments for making red inks. Blends of different pigments and/or
dyes
can be used. The uncured ink can contain about 2 - 60 wt % colorant,
alternatively about 5 - 30 wt % colorant, alternatively about 5 - 10 wt
colorant.
The photoinitiator is selected to respond to the wavelength of UV
radiation to be used for photoinitiation. It is also important to consider the
color
of the ink in selecting the photoinitiator because, as indicated above, it is
necessary for the UV light to penetrate the ink composition to initiate the
cure.
More specifically, penetration is sometimes required in order to cure the
portion
of the ink which is beneath the surface. Penetration typically is most
difficult
when black or white pigments are used. Non-limiting examples of
photoinitiators
to be used in conjunction with black pigment include sulfur-type
photoinitiators
such as isopropyl thioxanthone, and benzophenone and its derivatives including
acetophenone types and thioxanthones. Photoactivators can be used in
conjunction with one or more photoinitiators. Non-limiting examp~es of
suitanie
photoactivators are amine-type photoactivators such as ethyl 4-dimethylamino
benzoate. The uncured ink may contain about 0.3 - 5 wt % photoinitiator,
alternatively about 1 - 4 wt % photoinitiator, alternatively about 3 - 4 wt
photoinitiator. Blends of different photoinitiators, or photoinitiators and
photoactivators can be used.
A thinning agent can be added to lower the viscosity of the uncured ink
composition or to contribute to impact resistance or flexibility. When a
monomer
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-13-
is used as a thinning agent, it optionally can be a photopolymerizable monomer
that forms a polymeric structure upon irradiation. In contrast, when solvents
are
used as thinning agents, they evaporate during curing. The monomer can be a
monofunctional, difunctional or multifunctional acryiate. Non-limiting
examples
of suitable monomers include 1,6 hexanediol diacrylate, butanediol diacrylate,
trimethylol propane diacrylate, tripropylene glycol diacrylate and
tetraethylene
glycol diacrylate.
The uncured ink may contain about 10 - 70 wt % monomer, alternatively
about 10 - 60 wt % monomer, alternatively about 10 - 55 wt % monomer. The
combination of monomer plus oligomer may constitute about 45 - 80 wt % of
the uncured ink, optionally about 50 - 80 wt %, optionally about 60 - 80 wt
of the ink.
Non UV curable quick-drying resins which help in ink transfer from the pad
to the ball can be added. Non-limiting examples of such resins are vinyl
resins,
nitrocellulose, acrylic resins, and other quick-drying, film-forming resins.
One
contemplated resin is an acrylic-OH functional resin made by McWorther, Inc.
of
Carpentersville, IL, sold as Resin 975. Typically, if such resins are used,
they are
added in an amount up to about 30 parts by weight based upon 100 total parts
by weight of uncured ink composition.
When a solvent is used in the UV curable ink, it typically is a liquid with
a fast to moderate evaporation rate which, upon partial evaporation causes the
ink to be tacky, and thereby promotes transfer onto and off an ink pad. A
solvent also can be the medium in which a photoinitiator is dissolved. Non-
limiting examples of suitable solvents include aromatic solvents such as
toluene,
xylene, and ester types such as butyl acetate. The uncured ink may include
about 1 - 30 wt % solvent, optionally about 5 - 20 wt % solvent, optionally
about 8 - 10 wt % solvent.
Wetting agents can be added to prevent beading of the ink upon
application to the golf ball. Suitable wetting agents include, but are not
limited
to, silicone surfactants and fluorocarbon surfactants. The uncured ink may
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-14-
include about 0 - 2 wt % wetting agent. Other additives that do not adversely
affect the pad transfer and impact resistance of the ink also can be
incorporated
into the ink composition.
As long as sufficient durability is maintained, extender pigments such as
talc, barium sulfate and the like can be added to improve transferability. For
use
in ink jet printers, the particle size of the extender pigments should be
small
enough to facilitate passage through the orifices of the printer. This would
include finely divided (about less than 0.1 micron or alternatively less than
100
Angstroms) silicas, clays, or talcs, or combinations of these. Typically, if
such
materials are used, they constitute about 10 - 40 wt %, alternatively 20 - 30
wt
%, of the uncured ink formulation.
It has been found that by replacing part or all of the extender pigments
such as talc and barium sulfate with aluminum trihydroxide (Al(OH)3~3H20)
(ATH) filler, a number of significant improvements to the UV ink will result
with
respect to printing, curing and processing. Additionally, the inclusion of ATH
will
have minimal effect on the color of the ink. Furthermore, ATH has low oil
absorption, thus ink viscosity is increased very little. When up to 50 wt %
ATH
based upon the total (uncured) weight of ink is added, ink transfer from a pad
to
a substrate is improved. Significantly, ATH does not absorb UV light so curing
of the ink is not impeded. For use in ink jet printing, ATH particle size
should be
small enough to facilitate passage through ink jet orifices.
When ATH is used in a UV curable game ball ink, it generally is included
in an amount of 10 - 50 wt % based upon the total weight of the ink prior to
curing. ATH may be employed in an amount of 10 - 32 wt %, alternatively 20
- 30 wt %. It is believed that ATH loadings up to at least 50 wt % based upon
the weight of (uncured) ink may be useful for providing an overall balance of
properties. Greater quantities of ATH can be used when a low cost ink is
desired
and durability requirements are not stringent. Lower quantities of ATH are
useful
when higher durability is needed. The ATH can be used in a quantity
appropriate
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-15-
to impart to the ink a balance of properties such as pad transfer and
durability
of the ink.
If ATH is used in combination with talc, barium sulfite, or the like, the
ratio of ATH to talc, etc., may be about 1:1.
The use of ATH does not impede the curing process. The surface tension
of the ink affects the wetability of the substrate. The surface tension of the
ink
desirably is not substantially higher than the surface tension of the
substrate
upon which it is printed. The viscosity of the ink is one factor that will
affect the
thickness of the indicia on the cover. If the indicia are too thick, the UV
radiation may not penetrate the indicia and complete curing may become
difficult. On the other hand, if the indicia are too thin, the durability of
the ink
layer may be insufficient for conditions of play. The indicia have thickness
of
less than about 100 microns, optionally about 10 - 40 microns, optionally
about
13 - 30 microns, optionally about 20 - 25 microns.
The cured ink is contemplated to be sufficiently flexible to exhibit good
impact resistance. It is advantageous for the top coat which is applied over
the
ink to react with the ink to hold the ink in place, or to have adhesion by
hydrogen
bonding and/or van der Waals forces. As a non-limiting example, the ink can be
used in conjunction with a two-component polyurethane top coat, such as a top
coat based on polyester or acrylic polyols and aliphatic isocyanates such as
hexamethylene diisocyanate or isophorone diisocyanate trimers.
As one non-limiting example, a UV curable ink formulation of the invention
which is used for marking golf balls can be prepared and used in the following
way. The photoinitiator is dissolved in the thinning agent, which is then
mixed
with an oligomer, and a pigment. The mixture is placed in a dispenser for use
in direct or indirect ink jet printing. A primed but unfinished golf ball is
obtained.
The ball includes, for example, a core, and a durable cover having a dimpled
surface. Alternatively, the core and cover can be formed in one piece. Indicia
formed from the UV curable ink are ink jet printed on to the golf ball cover
either
directly or indirectly by use of a transfer medium. The unfinished golf ball
is then
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-16-
subjected to UV treatment under conditions sufficient to at least commence
curing of the ink. After photoinitiation, curing of the ink is substantially
complete
within a time period of between less than one second and a few seconds.
A top coat layer is placed over the indicia. The top coat is optionally
applied at least partially, and optionally completely, after the ink is cured.
The
top coat layer assists in keeping the indicia on the golf ball surface, as
indicated
above, and therefore the adhesion of indicia to the golf ball does not need to
be
as strong as will be required if the ink constitutes the outer layer of the
ball. The
top coat typically has a thickness of 10 - 40 microns.
The conditions of UV exposure which are appropriate to cure the ink can
be ascertained by one having ordinary skill in the art. For example, it has
been
found that when a golf ball passes through a UV treatment apparatus at a rate
of about 10 ft./min. (about 3 m/min.) at a distance of about 1'/< - 1'/4
inches
(about 3.2 - 4.4 cm) from a UV light source which has an intensity of e.g. 200
- 300 watts/in2 (31 - 47 wattslcm2), the indicia may be exposed to UV
radiation
for no more than a few seconds, optionally no more than about 1 second,
optionally no more than about 0.7 seconds. Higher and lower UV lamp
intensities, distances, and exposure times may be used as long as the cured
ink
meets the applicable durability requirements. Excess UV exposure is avoided to
prevent degradation of the substrate. The ink can be UV cured prior to
application of any top coat.
The pad to be used for transfer of the UV ink according to one
embodiment of the invention can contain silicone. This type of pad has good
elasticity, durability and softness and an appropriate surface tension. Other
types of pads also can be used.
The ink can be applied on a non-UV-labile surface of a game ball.
According to the invention, it is generally not necessary to pretreat the
surface
prior to application of the ink. If it is desired to apply the UV curable ink
on an
extremely smooth surface upon which transfer is poor, the portion of the
surface
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-17-
to be stamped can be chemically or physically etched or abraded in order to
provide an ink-receptive surface.
The ink of the invention has a Sward hardness (ASTM-D 2134-66) after
curing of about no more than 55, alternatively about no more than 40,
alternatively about no more than about 20.
The UV curable ink of the invention provides for durability sufficient to
meet stringent durability standards required for commercial grade golf balls.
The
durability of the ink can be determined by testing stamped golf balls in a
variety
of ways, including using the wet barrel durability test procedure.
Durability according to the wet barrel durability test procedure is
determined by firing a golf ball at 135 ft/sec (at 72°F) (41 mls (at
22°C)) into 5-
sided steel pentagonal container, the walls of which are steel plates. The
container 110, which is shown schematically in Figure 4, has a 19 'h inch
(49.5
cm) long insert plate 1 12 mounted therein, the central portion 114 of which
has
horizontally extending square grooves on it which are intended to simulate a
square grooved face of a golf club. The grooves, which are shown in an
exaggerated form in Figure 5, have a width 130 of 0.033 inches (0.084 cm), a
depth 132 of 0.100 inches (0.25 cm), and are spaced apart from one another
by land areas 134 having a width of 0.130 inches (0.330 cm). The five walls
1 16 of the pentagonal container each have a length of 14 %Z inches (36.8 cm).
As shown in Figure 4, the inlet wall is vertical and the insert plate is
mounted
such that it inclines upward 30° relative to a horizontal plane away
from opening
120 in container 110. The ball travels 15 '/Z - 15 3/4 inches (39.4 - 40 cm)
horizontally from its point of entry into the container 110 until it hits the
square-
grooved central portion 1 14 of insert plate 1 12. The angle between the line
of
trajectory of the ball and the insert plate 1 12 is 30°. The balls are
subjected to
70 or more blows (firings) and are inspected at regular intervals for breakage
(i.e., any signs of cover cracking or delamination). If a microcrack forms in
a
ball, its speed will change and the operator is alerted. The operator then
visually
inspects the ball. If the microcrack cannot yet be observed, the ball is
returned
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/Z3150
-18-
to the test until a crack can be visually detected. The balls are then
examined
for adhesion of the ink.
The following examples are included to further describe the invention.
EXAMPLE 1
A golf ball printing ink was prepared which contains:
5 parts by weight 1,6 hexanediol diacrylate (sold by Sartomer, Exton, PA),
17.5 parts by weight black pigment paste in diacrylate monomer, sold as
Carbon Black UV Dispersion 998415 (Penn Color, Doylestown, PA),
35 parts by weight of an aliphatic urethane acrylate oligomer (CN965,
sold by Sartomer, Exton, PA),
0.5 parts by weight isopropyl thioxanthone, C,eH,40S, a sulfur-type
photoinitiator (ITX, distributed by Aceto Chemical, Lake Success, NY),
1 part by weight ethyl 4-dimethylamino benzoate, C"H,5N02, an amine-
type photoactivator (EDB, distributed by Aceto Chemical, Lake Success, NY),
4.4 parts by weight xylene solvent, and
4.4 parts by weight butyl acetate solvent.
The photoinitiator and photoactivator were dissolved in the xylene/butyl
acetate
solvent blend. The ink was pad printed using a silicone pad on unprimed,
dimpled ionomeric covers of several dozen golf balls. The ink had a viscosity
of
about 27,500 centipoise ("cps") at the time of application.
The balls containing the stamped indicia were passed through a Uvex UV
treatment apparatus Lab Model #14201 at a rate of 10 feet/min. (3 m/min.),
using a lamp intensity of 235 watts/in2 (36.4 watts/cm2~ and wavelength range
of 200 - 400 nm with the indicia being located about 1 3~4 inches 14.4 cm)
from
the UV light source. The ink was cured in less than about 1 second and had a
Sward hardness of about 14 after curing was complete.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
_19_
The golf balls were then coated with a solvent-borne polyurethane top
coat formed from a polyester type hexamethylene diisocyanate. The adhesions
of the indicia on the balls were tested for durability according to the wet
barrel
durability test procedure described above. After wet barrel durability
testing, the
balls were examined and it was found that no more than about 20% of the
surface area of the original ink logo was removed.
EXAMPLE 2
The procedure of Example 1 was repeated with excepting that the ink
formulation that was used contained:
10 parts by weight 1,fi hexanediol diacrylate (sold by Sartomer),
35 parts by weight black pigment paste in diacrylate monomer, sold as
Carbon Black UV Dispersion 998415,
70 parts by weight of a difunctional aliphatic urethane acrylate oligomer
(Ebecryl 4833 sold by UCB, RadCure,lnc., Smyrna, GA),
1 part by weight isopropyl thioxanthone, C,6H,40S (ITX), and
2 parts by weight ethyl 4-dirnethylamino benzoate (EDB).
The ink had a viscosity of about 25,000 cps. The ink was cured in about 1
second and produced a film having a Sward hardness of about 12. The balls
were subjected to the wet barrel durability test procedure. After the wet
barrel
durability testing, it was found that no more than about 20% of the ink logo
was
removed.
EXAMPLE 3
The procedure of Example 1 was repeated excepting that the CN965
oligomer was replaced by a difunctional oligomer sold as Ebecryl 8402 (UCB
RadCure, inc., Smyrna, GA). The ink had a viscosity of about 18,000 cps. The
ink was cured in about 1 second and produced a film having a Sward hardness
of about 14. The ink was found to be as nearly as durable as that of Examples
1 and 2.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-20-
EXAMPLE 4
The procedure of Example 1 was repeated excepting that the ink
formulation that was used contained:
7.3 parts by weight 1,6 hexanediol diacrylate (sold by Sartomer, Exton,
PA1,
19.2 parts by weight black pigment paste in diacrylate monomer, sold as
ICU 386 (Industrial Color Inc., Joliet, IL),
21 .0 parts by weight aliphatic polyether urethane oligomer (BR-571,
Bomar Specialties Company, Winsted, CT),
0.5 parts by weight isopropyl thioxanthone, C,6H,40S, a sulfur-type
photoinitiator (ITX, distributed by Aceto Chemical, Lake Success, NY),
1 part by weight ethyl 4-dimethylamino benzoate (EDB),
1 1.4 parts by weight talc (Vantalc 6H, Vanderbilt, Norwalk, CT),
22.9 parts by weight barium sulfate (106 Low-Micron White Barytles,
Whittaker, Clark & Daniels, Inc., South Plainfield, NJ),
12.1 parts by weigh butyl acetate solvent, and
4.6 parts by weight propylene glycol monomethyl ether acetate solvent.
The ink was applied directly to ionomeric covers of golf balls, and also
over ionomeric covers to which a water-borne polyurethane primer layer had
been applied prior to application of the ink. The ink was cured in about 1
second
and produced a film having a Sward hardness of about 14. The balls were top
coated and subjected to the wet barrel durability test procedure. After the
wet
barrel durability testing, it was found that no more than about 20% of the ink
logo was removed.
COMPARATIVE EXAMPLE 1
The procedure of Example 1 was repeated with the exception that a
commercially available UV curable ink was used, namely Blk #700801 (Traps
Tech, Carol Stream, iL). The ink had a viscosity of about 6,000 cps. The ink
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-21-
was cured in about 1 second and produced a film having a Sward hardness of
about 26. After the wet barrel durability test only the outline of the logo
remained. Most of the ink in the dimples and on the land areas had been
removed. Intercoat adhesion between the ink and top coat was poor.
COMPARATIVE EXAMPLE 2
The procedure of Example 1 was repeated on several golf balls with the
exception that a commercially available UV curable ink was used, namely L-526-
163-B (Qure Tech, Seabrook, NH). The ink had a viscosity of about 28,500 cps.
The ink was cured in about 1 second and produced a film having a Sward
hardness of about 20. As a result of the wet barrel durability test, the ink
on at
least about 60% of the surface area of the logo had been removed. It is
believed
that the ink was too brittle to withstand the conditions of the wet barrel
durability test.
EXAMPLE 5
ATH-containing formulation 1, shown below, was prepared:
ATH-Containing Formulation 1 Parts by weight
Acrylic -OH functional resin' 540.5
Acetate and aromatic hydrocarbon solvent blend2 189.2
ATH3 270.3
1000.0
' McWorther Resin 975 (McWorther, Inc., Carpentersville, IL).
Z Summit Ink Reducer, Summit PT #910527 (Summit Screen Inks, No. Kansas City,
MO) Alternatively, a mixture
based upon 43.4 parts by weight butyl acetate, 28.3 parts by weight xylene and
28.3 parts by weight propylene
glycol monomethyl ether acetate can be used.
' ATH SpaceRite S-3 (ALCOA Industries, Bauxite, AR).
The ATH-containing formulation 1 was then used to form a golf ball ink which
contained:
5 parts by weight aliphatic urethane triacrylate (BR-990, Bomar Specialties
Co., Winsted, CT),
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-22-
35 parts by weight ATH-containing formulation 1,
5.5 parts by weight trimethylolpropane triacrylate (TMPTA) (Sartomer Co.,
West Chester, PA),
parts by weight black dispersion in oligomer/monomers
5 (ICU 386, Industrial Color Inc., Joliet, IL),
0.3 parts by weight isopropyl thioxanthone, C,BH,40S, a sulfur-type
photoinitiator (ITX, distributed by Aceto Chemical, Lake Success, NY),
1 part by weight ethyl 4-dimethylamino benzoate, C"H,5N02, an amine-
type photoactivator (EDB, distributed by Aceto Chemical, Lake Success, NY),
and
10 parts by weight ATH (SpaceRite S-3, ALCOA Industries, Bauxite, AR1.
All ingredients were mixed and dispersed on high speed mixing equipment. The
ink was pad printed using a silicone pad on unprimed, dimpled ionomeric covers
of several dozen golf balls.
The balls containing the stamped indicia were passed through a Uvex UV
lamp at a rate of 10 feet/min. (3 m/min.), using a lamp intensity of 235
watts/in.2 (36.4 watts/cm2) and a wavelength range of 200 - 400 nm with the
indicia being located about 1 3/4 inches (4.4 cm) from the UV light source.
The
ink was cured in less than one second.
The golf balls were then coated with a two component polyesterlaliphatic
polyisocyanate clear coat.
The printability, jetness, detail image, pad release, and durability of the
ink
was evaluated and was compared with three sets of control inks, designated as
Control A, Control B, and Control C. The formulations of the Control A and
Control B inks are shown below:
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-23-
Control A
parts by wt.
Aliphatic urethane-acrylic oligomer' 6.45
Acrylic -OH functional resin2 42.96
Acetate and aromatic hydrocarbon
solvent blend3 8.85
Talc4 5.59
Barium sulfates 12.89
Black dispersion in oligomer/monomerfi 6.01
TMPTA' 15.18
Isopropyl thioxanthonee 0.69
Ethyl 4-dimethylamino benzoate9 1.38
100.00
1 5 ' BR-571 (Bomar Specialties Co., Winsted, CT).
2 McWorther Resin 975 (McWorther, Inc., Carpentersville, IL).
' Summit Ink Reducer (Pt# 910527, Summit Screen Inks, No. Kansas City, MO1.
° Van Talc #6H (Vanderbilt, Norwalk, CT).
5 Barytes #22 (Whittaker, Clark & Daniels, Inc., South Plainfield, NJ1.
6 ICU 386 (Industrial Color Inc., Joliet, IL).
' (Sartomer Co., West Chester, PA).
a ITX (distributed by Aceto Chemical , Lake Success, NYI.
9 EDB (distributed by Aceto Chemical, Lake Success, NYI.
Control B
parts bV Wt.
Epoxy-acrylate oligomer' 19.24
Acrylic -OH functional resin2 27.70
Acetate and aromatic hydrocarbon
solvent blend3 13.84
Talc4 7.69
Barium sulfates 7.69
Black dispersion in oligomerlmonomers 6.15
Polyester-acrylate oligomer' 15.38
Isopropyl thioxanthone8 0.77
Ethyl 4-dimethylamino benzoate9 1 .54
100.00
' Ebecryl 3700 (Rad-Cure, Smyrna, GA).
2 McWorther Resin 975 (McWorther, Inc., Carpentersville, IL).
' Summit Ink Reducer (Pt# 910527, Summit Screen Inks, No. Kansas City, MO1.
' Van Talc 6H (Vanderbilt, Norwalk, CT~.
5 Barytes #22 (Whittaker, Clark & Daniels, Inc., South Plainfield, NJ).
g ICU 386 (Industrial Color Inc., Joliette, IL).
' Ebecryl 80 (Rad-Cure, Smyrna, GA).
8 ITX (distributed by Aceto Chemical, Lake Success, NY).
9 EDB (distributed by Aceto Chemical, Lake Success, NY).
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-24-
Control C was Trans Tech ink # 2P37-2 (Trans Tech, Carol Stream, II_). The
ratings for the various ink formulations are shown below:
Ink PrintabilityJetness Detail Pad Durability
Image Release
Example 1 'h 1 1 1 '/2 1
Control 2 %Z 2 %2 2 2 %2 1
A
Control 3 2 '/2 2 '/Z 3 2 '/Z
B - 3
I Control 1 '/2 - 1 1 1 %Z - 2 %2
C 2 2
5
Ratings were from 1 - 5 with 1 being ideal and 5 being unacceptable. All of
the
balls of Example 5 and the balls of Controls A, B and C were covered with a
one-
coat top coating system of 160 mg, the top coating being a two component
polyester/aliphatic polyisocyanate clear coat.
The ink of Example 5 had a oligomer/monomer content of 22.608 wt %,
an acrylic resin content of 21.508 wt %, a black pigment content of 3.08 wt %,
an ATH pigment content of 31.63 wt %, a solvent content of 20.008 wt % and
an initiator content of 1.62 wt %. The density of the ink was 10.68 Ibs./gal.
(1.28 kg/L), the total nonvolatiles content was 80%, and the volatile organic
compounds constituted 2.14 Ibs./gal. (0.256 kg/L). The viscosity of the ink
was
1 1,000 cps at the time of application. After curing, the smudge resistance of
the ink was tested using methyl ethyl ketone solvent. No smudging occurred.
It has been found that the solvent content of the ink can be significantly
increased without reducing the quality of the identification stamp. For
example,
by further reducing the ink by 30% (by adding solvent), the viscosity of the
ink
should decrease to about 1420 cps. An ink with this low viscosity tends to
have
better printability than more viscous inks on certain pad printing machines.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-25-
Figure 6 shows a silicone pad after 12 golf balls have been stamped with
a particular type of ink. Figure 6A (150) shows the stamp after stamping with
the ink of Control A. Figure 6B (152) shows the silicone pad after stamping
with
the ink of Control B. Figure 6C (154) shows the pad after stamping with the
ink
of Example 5. Figure 6D (155) shows the pad after stamping with Control C.
As indicated by the resulting stamps, the best transfer, i.e. the least
quantity of
ink remaining on the stamp, resulted from the use of the ink of Example 5.
EXAMPLE 6
ATH-containing formulation 2, shown below, was prepared:
ATH-Containing Formulation 2 Parts by weight
Acrylic-OH functional resin' 21.84
Propylene glycol monomethyl ether acetate solvent2 4.85
ATH3 20.70
Talc4 19.50
Black dispersion in oligomer/monomer5 9.50
76.39
' McWorther Resin 975, (McWorther, Inc., Carpentersville, IL).
2 Dow Chemical (and othersl.
3 ATH SpaceRite S-3 (ALCOA Industries, Bauxite, AR).
° Van Talc #6H (Vanderbilt, Norwalk, CT).
5 ICU 386 (Industrial Color Inc., Joliet, IL).
After the formulation was mixed, the following materials were added:
1.31 parts by weight butyl acetate, (Eastman Chemical and others),
6.16 parts by weight Aromatic 100 or HiSol 53, (Ashland Chemicals),
3.08 parts by weight cyclohexanone (Ashland Chemicals),
0.50 parts by weight isopropyl thioxanthone, C,6H,40S, a sulfur-type
photoinitiator (ITX, distributed by Aceto Chemical, Lake Success, NY),
1 part by weight ethyl 4-dimethylamino benzoate, C"H,5N02, an amine-
type photoactivator (EDB, distributed by Aceto Chemical, Lake Success, NY),
5.78 parts by weight aliphatic urethane triacrylate (UV curable resin) (BR-
990, Bomar Specialties Co., Winsted, CT), and
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-26-
5.78 parts by weight trimethylolpropane triacrylate (UV curable resin)
(TMPTA) (Sartomer Co., West Chester, PA).
The total parts by weight were 100. All ingredients were mixed and
dispersed using high speed mixing equipment.
The ink was pad printed using a silicone pad on unprimed, dimpled
ionomeric covers of a large number of golf balls. The golf balls containing
stamped indicia were passed through a Uvex UV lamp at a rate of 10 ft/min. (3
m/min.), using a lamp intensity of 235 watts/in.2 (36.4 watts/cm2) and a
wavelength range of 200 - 400 nm with the indicia being located at about 1 3/4
inches (4.4 cm) from the UV light source. The ink was cured in less than one
second.
The golf balls were then coated with a two-component polyester/aliphatic
pofyisocyanate clear coat and were subjected to the wet barrel durability test
procedure. After the wet barrel durability testing, it was found that no more
than about 20% of the ink logo was removed.
EXAMPLE 7
The procedure of Example 6 was repeated with the exception that the
quantity of ATH was reduced to 19.20 parts by weight, and the ATH-containing
formulation (ATH-containing formulation 2) included only 0.22 parts by weight
of black dispersion in oligomer/monomer (CU 386, Industrial Color Inc.,
Joliet,
IL), and further contained 8.16 parts of a first red dispersion in
oligomer/monomer (ICU Red Lake C, Industrial Color Inc., Joliet, IL) and 2.62
parts of a second red dispersion in oligomer/monomer (ICU Lithol 388 Red,
Industrial Color Inc., Joliet, IL). All ingredients were mixed and dispersed
an high
speed mixing equipment. The total parts by weight were 100.
After the wet barrel durability testing, it was found that no more than
about 20% of the ink logo was removed.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-27-
EXAMPLE 8
ATH-containing formulation 3, shown below, was prepared:
ATH-Containing Formulation 3 Parts by weiaht
Acrylic -OH functional resin' 30.78
Butyl acetate solvent 4.67
Xylene solvent2 3.04
Propylene glycol monomethyl ether acetate solvent 3.04
ATH3 31.66
73.19
' McWorther Resin 975 (McWorther, Inc., Carpentersville, IL).
2 Shell.
3 ATH SpaceRite S-3 (ALCOA Industries, Bauxite, AR).
After mixing, the following materials were added:
5.69 parts by weight red dispersion in oligomer/monomer (ICU Red Lake
C, Industrial Color Inc., Joliet, IL),
1.92 parts by weight red dispersion in oligomer/monomer (ICU Lithol
Rubine, Industrial Color Inc., Joiiet, IL),
0.47 parts by weight black dispersion in oligomer/monomer (ICU 386,
Industrial Color Inc., Jofiet, IL),
0.49 parts by weight isopropyl thioxanthone, C,6H,40S, a sulfur-type
photoinitiator (ITX, distributed by Aceto Chemical, Lake Success, NY),
1.14 parts by weight ethyl 4-dimethylamino benzoate, C"H,4N02, an
amine-type photoactivator (EDB, distributed by Aceto Chemical, Lake Success,
NY),
8.14 parts by weight aliphatic urethane triacrylate (BR-990), Bomar
Specialties Co., Winsted, CT), and
8.95 parts by weight trimethylolpropane triacrylate (TMPTA) (Sartomer
Co., West Chester, PA).
The total parts by weight were 99.99.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
_28_
To provide for optimum printing, the viscosity of the ink was reduced to
1200 cps by adding 15 wt % (based upon the weight of the ink before
reduction) of a solvent which was made by mixing 43.4 parts by weight butyl
acetate, 28.3 parts by weight xylene and 28.3 parts by weight propylene glycol
monomethyl ether acetate.
The ink was printed on a number of golf balls. The golf balls were then
coated with a two-component polyester/aliphatic polyisocyanate clear coat and
were subjected to the wet barrel durability test procedure. After the wet
barrel
durability testing, it was found that no more than about 20% of the ink logo
was
removed. The balls which were initially printed had a crisp image. After time,
some ghosting appeared.
EXAMPLE 9
ATH-containing formulation 4, as shown below, was prepared:
ATH-Containing Formulation 4 Parts by Weight
Acrylic -OH functional resin' 21.63
Butyl Acetate 7.57
ATH2 21.34
Talc3 19.35
First red dispersion in oligomer/monomer4 7.04
Second red dispersion in oligomer/monomer5 2.26
Black dispersion in oligomer/monomers 0.61
Xylene solvent 3.80
83.60
' McWorther Resin 975 (McWorther, Inc., Carpentersville, IL).
2 ATH SpaceRite S-3 (ALCOA Industries, Bauxite, AR1.
3 Van Talc #6H (Vanderbilt, Norwalk, CT).
° ICU Red Lake C, (industrial Color Inc., Joliet, IL).
5 ICU Lithol Rubine 388, (Industrial Color Inc., Joliet, ILI.
6 ICU 386 (Industrial Color Inc., Joliet, IL).
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
_29-
After mixing, the following materials were added:
3.80 parts by weight propylene glycol monomethyl ether acetate solvent,
0.38 parts by weight isopropyl thioxanthone, C,sH,~OS, a sulfur-type
photoinitiator (ITX, distributed by Aceto Chemical, Lake Success, NY),
0.86 parts by weight ethyl 4-dimethylamino benzoate, C"H,QN02, an
amino-type photoinitiator (EDB, distributed by Aceto Chemical, Lake Success,
NY1,
5.69 parts by weight aliphatic urethane triacrylate (BR-990, Bomar
Specialties Co., Winsted, CT), and
5.69 parts by weight trimethylolpropane triacrylate (TMPTA) (Sartomer
Co., West Chester, PA).
Total parts by weight were 100.02.
The ink was printed on a number of golf balls. The image was very dark.
A satisfactory image probably could have been obtained using a lower level of
black dispersion. The golf balls were then coated with a two-component
polyester/aliphatic polyisocyanate clear coat and were subjected to the wet
barrel
durability test procedure. After the wet barrel durability testing, it was
found
that no more than about 20% of the ink logo was removed.
EXAMPLE 10
Referring to Figure 7, an ink jet printer (Epson Stylus Color 640) 200 was
used to print an image from a JPEG computer file onto a polysilicone coated
sheet of paper (Dow Corning HS2) 202. This resulted in an ink jet logo 204 on
the silicone coated paper 202.
An ionomer covered golf ball 206 was obtained which had been coated
with an ink retaining primer coat formed from 100.00 parts by weight of
Witcobond 235 (Witco), which is a water borne polyurethane primer, and 7.0
parts by weight of amorphous silica (Hi-Sil 915, PPG, Pittsburgh, PA). After
the
primer coating had dried, the image 204 on the silicone paper 202 was
CA 02344404 2001-03-15
WO 00/20219 PCTNS99/23150
-30-
transferred to the surface of the golf ball 206 using a golf ball logo
stamping
machine 208.
More particularly, the ball logo stamping machine 208 has a horizontal arm
210 to which is attached a plunger 212 carrying a transfer pad 214. The
silicone coated paper 202 holding the logo 204 was placed underneath the
transfer pad 214. The plunger 212 advanced the transfer pad 214 against the
logo 204, lifting the logo image 204 onto the transfer pad 214. The transfer
pad
214 retracted, moving along the arm 210 to a second position beneath which
a golf ball 206 was held. At this second position, the plunger 212 advanced
the
transfer pad 214 against the primed golf ball 206, stamping the newly
imprinted
image onto the ball 206.
After the ink was dry, the primed golf ball 206 with the stamped image
was then coated with a top coat 216 of the following formulation:
Parts by Weight
Polyol (Desmophen 670-80, Bayer Corp.) 100.0
Isocyanate (Desmodur N-3200, Bayer Corp.) 30.0
Methyl amyl ketone solvent 50.0
Butyl acetate solvent 25.0
Methyl isobutyl ketone solvent 25.0
UV absorber (Sandoz 3206) 2.0
UV stabilizer (Tinavin 292, CibaGeigy) 1 .0
233.0
After the top coat was cured at an elevated temperature, as shown at
218, the ball was durability tested using the wet barrel test described above.
About 80% of the ink logo remained. This process produced a multi-color logo
with good distinction, recognition and durability on a dimpled and curved
surface
of a golf ball.
EXAMPLE 11
An ionomer covered golf ball was obtained which had been coated with
an ink retaining primer coat formed from 100.00 parts by weight of Witcobond
235 (CK Witco, Stamford, CT), which is a water borne polyurethane primer,
CA 02344404 2001-03-15
WO 00/20219 PCTNS99/23150
-31-
10.0 parts of talc (magnesium silicatel, 1.0 part by weight of amorphous
silica
(Hi-Sil 532EP, PPG, Pittsburgh, PA1, and 5 parts by weight of polyaziridine
(Zeneca Resus, Wilmington, MA). The primer coating was allowed to dry.
A solvent-based printing ink of the following formulation was prepared:
50.0 parts by weight isopropanol,
2.0 parts by weight ethylene glycol monobutyl ether,
15.0 parts by weight methyl isobutyl ketone (MIBK),
6.0 parts by weight Savinyl Dyes, solvent soluble metal complex dyes,
sold by Clariant Corp., Coventry, R.I., and
3.0 drops BYK 346, a polyether modified polydimethyl siloxane, sold by
BYK Chemie, Wallingford, Connecticut.
The above ink formulation was ink jet printed directly onto the primed golf
ball using an Epson Stylus Color 640 ink jet printer, a drop on demand
piezoelectric printer. The drive system of the ink jet printer was physically
adapted to allow for printing directly on to the golf ball as shown in Figure
10.
The adaptation was constructed in such a manner that the game ball had the
identical indexing or rotational speed as paper that is driven through the
printer.
Referring to Figure 10, a rotational system 305 consisting of a series of
shafts
connected by belts and pulleys rotated the main drive shaft 300. A game ball
310 was held by two suction units 315 that rotated with the main drive shaft
300. The rotational system 305 advanced the main drive shaft 300 at such a
rate that the game ball 310 advanced at a rate identical to the index speed of
a
piece of paper. The ink jet printhead 320 advanced horizontally across the
game
ball 310, printing the desired image onto the game ball 310 in a series of
passes.
The ink had a viscosity of about 6 cps at the time of application.
The resulting golf ball had a clean, durable and opaque image found
thereon.
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-3 2-
After the ink was dry, the golf ball with the image thereon was then
coated with a solvent-borne two-part aliphatic polyurethane top coat which is
described in U.S. Patent No. 5,459,220. The opacity, clarity and color of the
image did not change upon application of the top coat.
The ball was durability tested using the wet barrel test, breaking after 197
blows. The results after durability testing are shown in Figure 9. After
testing,
the balls were examined and it was found that about 80% of the ink logo
remained. This process produced a multi-color logo with good distinction,
recognition and durability on a dimpled and curved surface of a golf ball.
This result can be compared to the results after durability testing a golf
ball that was custom stamped by pad printing using a conventional solvent-
borne
pad printable ink. Figure 8 depicts a golf ball that has been subjected to wet
barrel testing after an indicia was imprinted via custom stamping. The ball
broke
after 186 blows. After wet barrel durability testing, far less of the ink logo
remained on the custom stamped ball in Figure 8 than the ink jet printed ball
in
Figure 9.
EXAMPLE 12
The procedure of Example 11 was repeated with the exception that a
water-based printing ink of the following formulation was substituted:
50.0 parts by weight water,
5.0 parts by weight isopropanol,
6.0 parts by weight Sandovac-L Dyes, sold by Clariant Corp, Coventry,
R.I., and
3.0 drops BYK 346, a polyether modified polydimethyl siloxane, sold by
BYK Chemie, Wallingford, Connecticut.
The resulting golf ball had a clear and durable image formed thereon.
While the opacity of this image was slightly less than that of the image on
the
ball of Example 1 1, the opacity could be improved by using a larger quantity
of
dye or by increasing the mixing intensity of the formula during preparation in
order to better disperse the dye:
CA 02344404 2001-03-15
WO 00/20219 PCT/US99l23150
-33-
COMPARATIVE EXAMPLE 3
The procedure of Example 11 was repeated excepting that a commercially
available glycol-based ink formulation, found in conventional ink jet ink
cartridges, namely Epson Ink Jet Printer ink formulation found in ink
cartridges
for use with the Epson Stylus Color 640 ink jet printer, was used. The ink had
a viscosity of about 5 or 6 cps. This process did not produce an acceptable
image.
EXAMPLE 13
A golf ball printing ink was prepared which contained Formula C. To
prepare Formula C, Formulas A and B were first prepared:
FORMULA A
)carts by wt.
Epoxy-acrylate oligomer' 70.0
Polyester-acrylate oligomer2 30.0
Butyl acetate 100.0
Methyl isobutyl ketone (MIBK) 100.0
Isopropyl thioxanthone8 0.7
Ethyl 4-dimethylamino benzoate9 1.5
302.2
' Ebecryl 3700 (Rad-Cure, Smyrna, GA).
2 Ebecryl 80 (Rad-Cure, Smyrna, GA).
a ITX (distributed by Aceto Chemical, Lake Success, NY).
9 EDB (distributed by Aceto Chemical, Lake Success, NY).
FORMULA B
parts by wt.
Formula A 40.0
Savinyl Dye' 1.0
41.0
' E.g., One of the following: Savinyl Blue GLS, Savinyl Yello RLS, Savinyl
Black RLSN, or Savinyl Pink
6BLS (Clariant Corp., Coventry, R.I.).
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-34-
FORMULA C
parts by wt.
Formula A 20.0
Formula B 20.0
MIBK 10.0
50.0
The ingredients of Formula C were mixed and ink jet printed directly onto the
golf
ball primed with the primer of Example 11 and using the ink jet printer of
Example 1 1. The drive system of the ink jet printer, a piezoelectric printer,
was
physically adapted to allow for printing directly on to the golf ball.
The balls containing the stamped indicia were passed through a Uvex UV
treatment apparatus at a rate of about 10 feet/min. (3 m/min.), using a lamp
intensity of about 235 watts/in2 (36.4 watts/cm2' and wavelength range of
about
200 - 400 nm with the indicia being located about 1 3/4 inches (4.4 cm) from
the
UV light source.
The indicia on the ball were distinct and durable.
PROPHETIC EXAMPLE 14
A golf ball printing ink is prepared which contains:
parts by wt.
Epoxy-acrylate oligomer' 20.0
Acrylic -OH functional resin2 30.0
Acetate and aromatic hydrocarbon
solvent blend3 15.0
Black Dye4 15.0
Polyester-acrylate oligomer5 15.0
Isopropyl thioxanthones 1.0
Ethyl 4-dimethylamino benzoate' 1.5
' Ebecryl 3700 (Rad-Cure, Smyrna, GA).
2 McWorther Resin 975 (McWorther, Inc., Carpentersville, IL).
' Summit Ink Reducer (Pt#910527, Summit Screen Inks, No. Kansas City, MO).
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/23150
-35-
E.g., Savinyl Black RLS (Clariant Corp., Coventry, R.I.).
5 Ebecryl 80 (Rad-Cure, Smyrna, GA1.
6 ITX idistributed by Aceto Chemical, Lake Success, NY).
' EDB (distributed by Aceto Chemical, Lake Success, NY).
The ingredients are mixed. The ink is sufficiently diluted with solvent, e.g.,
butyl
acetate, to constitute a viscosity of between about 1 to 20 cps, optionally
between about 5 to 10 cps, optionally between about 5 to 6 cps.
The above ink formulation is ink jet printed directly onto the primed golf
ball using the ink jet printer of Example 11. The drive system of the ink jet
printer, a piezoelectric printer, is physically adapted to allow for printing
directly
on to the golf ball.
The balls containing the stamped indicia are passed through a Uvex UV
treatment apparatus at a rate of about 10 feet/min. (3 m/min.), using a lamp
intensity of about 235 watts/in2 (36.4 watts/cm2) and wavelength range of
about 200 - 400 nm with the indicia being (coated about 1 3~4 inches (4.4 cm)
from the UV light source.
The golf balls are then coated with a solvent-borne polyurethane top coat
formed from a polyester type hexamethylene diisocyanate.
PROPHETIC EXAMPLE 15
The procedure of Example 12 is repeated excepting that a Hewlett
Packard 693C bubble jet printer, a drop on demand printer, is substituted for
the
Epson Stylus Color 640 ink jet printer.
PROPHETIC EXAMPLE 1 fi
The procedure of Example 12 is repeated excepting that 10 parts by
weight of black pigment, Microlith Black C-WA (CIBA Specialty Chemicals Corp.
USA, Newport, DE), is substituted for the Sandovac-L Dyes. The pH of the
composition is increased to at least 8.5 by adding an amine such as triethanol
amine.
As will be apparent to persons skilled in the art, various modifications
CA 02344404 2001-03-15
WO 00/20219 PCT/US99/Z3150
-36-
and adaptations of the structure above described will become readily apparent
without departure from the spirit and scope of the invention, the scope of
which is defined in the appended claims.
