[0001] This invention relates to spray dispensing and, more particularly, to spray dispensing
of metered quantities of semi-liquid products finding particular utility for depositing
a defined and metered pattern of, for example, an anhydrous cream antiperspirant product
on an axilla surface.
[0002] Spray dispensing is generally achieved by delivering a liquid product to a nozzle
under pressure induced, e.g., by a pump, pressurized gas, or a collapsible wall container.
Each of these dispensing systems have advantages and disadvantages that have made
them more or less suitable for a wide variety of products. The thinner and less viscous
the product, however, the easier it is to spray utilizing such pressure operated systems.
The thicker and more viscous the product, conversely, the harder it is to spray utilizing
such systems. Semi-liquid cream or like products, such as gels, thickened emulsions,
and the like; products having high tackiness, tenaciousness or cohesiveness; or products
having a very high solids content, are particufarty difficult to spray through a nozzle
utilizing conventional pump, pressurized gas, or collapsible wall dispensing systems.
[0003] Finger and trigger pumps as well as squeeze bottles, for example, are generally incapable
of providing sufficient operating pressures for spraying thick cream-like products
from nozzles and particularly for spraying products having a viscosity of 25 to 50
centipoise or higher. Gas operated systems are, of course, capable of supplying higher
nozzle pressures but gas operated systems are prone to other problems, especially
in inexpensive consumer product dispensing systems, including problems in providing
clean start and stop action and a uniform metered spray especially with thick, cohesive
products.
[0004] U.S. Patent No. 3,782,380 describes a device for dispensing fluid through a discharge
orifice in which the fluid is contained within a chamber having a moveable wall and
the moveable wall is contacted by a plunger assembly actuated by a compression spring.
In this case, the plunger assembly is arranged to push the moveable wall with a follow
through force along at least part of the chamber to dispense the product. This type
of action, while suitable for pressure dispensing of a fluent medium, is not generally
satisfactory for sp.ray dispensing of semi-liquid products.
[0005] In spray product dispensing, whether in the industrial/commercial sector or in the
consumer products sector, product safety is becoming increasingly recognized and even
mandated as a prime requisite. Conversely economic/market pressures often require
that such desirable increased safety be achieved without loss of convenience to the
user and within a familiar product-package framework. Simultaneously, pressures exist
to keep costs down, both in the immediate product costs to the consumer and in the
overall environmental costs involved in providing and delivering the product.
[0006] In the area of anti-perspirant/deodorant products for example, spray type products
have been preferred by a large segment of the market, presumably in large part because
of their "non-contact" mode of application; i.e., the product (as opposed to the package)
is not susceptible to being touched by others prior to or between uses by a specific
user as well as requiring only minimal user involvement with the target area.
[0007] Previous efforts to provide "non-contact" dispensing of products such as antiperspirant/deodorant
products without fluorocarbon aerosols have generally involved attempted substitutions
of other pressure sources for the dissolved pressurized aerosol gas, such as finger
pumps, trigger pumps, squeeze bottles or substitution of other gas systems. Since
these devices generally operate at lower pressures or lack long term uniformity of
pressure, product formulations having decreased viscosities have generally been deemed
necessary to permit successful spray application. Viscosity decreases, however, especially
by use of increased solvent or volatile levels, whether aqueous or anhydrous, have
generally not led to commercially satisfactory products, primarily because of increased
problems of perceived wetness, coldness, runniness, and/or stickiness.
[0008] Similar problems of wetness, coldness and/or stickness have been known to exist in
non-spray antiperspirant products.
[0009] In Belgian Patent No. 854,048, there are described certain highly stable anhydrous
antiperspirant creams that are formulated with highly thixotropic cream vehicles containing
particular concentrations of emollients and gelling agents which do not, in general,
impart an undesirable, cold, wet or sticky sensation when applied to the skin, which
exhibit minimal syneresis or bleeding or organic liquids from the thixotropic gel
structure and which do not dry out or form unacceptable crusts upon prolonged exposure
to the atmosphere. While the aforesaid disclosure does not relate to a spray application,
it does exemplify semi-liquid antiperspirant cream products which, in accordance with
the methods and apparatus of the present invention we have discovered can be spray
dispensed. However, it is also to be expressly understood that in its broader aspects
our invention is not limited to spray dispensing of antiperspirant creams but is of
general utility for spray dispensing of semi-liquid products as hereinelsewhere set
forth.
[0010] In the antiperspirant field, however, the formulations of Belgian Patent No. 854,048
provide unique advantages when sprayed in accordance with the present methods and
apparatus and form a unique combination therewith, enabling safe, convenient, aesthetically
and environmentally satisfactory non-contact application of stable non-crusting antiperspirant
products without wetness, coldness, stickiness or runnyness from a hand held and hand
actuated dispenser.
[0011] The present invention provides novel and improved methods of and apparatus for spray
dispensing a metered quantity of product in a controlled and uniform ballistic cluster
of closely defined particles, particularly suitable for semi-liquid products, such
as highly thixotropic, highly stable anhydrous antiperspirant creams.
[0012] The present method and apparatus provides for the "non-contact" delivery of antiperspirant
and/or deodorant products without, in general, imparting any undesirable, cold, wet,
sticky, or runny sensation to the skin and, particularly axilla surfaces, and having
improved safety in providing generally uniform particle size, minimization of inhalables,
and lack of any gaseous propellant.
[0013] The present invention, in addition to the foregoing, provides for the spray dispensing
of a cluster of semi-liquid particles from a pattern of discharge orifices ballistically
to the surface to impinge and merge thereon in a pattern generally reflecting a projection
of the locus set of the pattern of discharge orifices.
[0014] According to the present invention, there is provided a method of dispensing metered
quantities of a semi-liquid product from a filled substantially rigid container having
a fixed wall provided with at least one and preferably a plurality of generally open
and unobstructed discharge passageways and a moveable wall spaced apart from the fixed
wall by impacting the moveable wall with a moveable mass to induce a pressure pulse
to the product having sufficient energy to surge a metered quantity of product less
than the entire contents of the container through the discharge passageway with sufficient
velocity as to break away from the passageway and the remaining product within the
container for ballistic travel outward of the container as a cluster of generally
uniformly defined and moving particles.
[0015] The invention also provides an apparatus for dispensing a metered quantity of a semi-liquid
product comprising a substantially rigid container adapted to be filled with the semi-liquid
product and having a fixed wall provided with at least one generally open and unobstructed
discharge passageway, a moveable wall spaced apart from the fixed wall and a moveable
mass adapted to contact the moveable wall, wherein energising means provided for accelerating
the moveable impact mass so that it impacts the moveable wall with sufficient impact
force to induce a pressure pulse in the product of sufficient energy to surge a metered
quantity of product less than the entire content of the container and dependent upon
the momentum of the impact mass as a noodle or noodles through the discharge passageway
with sufficient velocity as to break away from the passageway and the remaining product
within the container to ballistically travel outwardly of the container fixed wall.
The spray dispenser of the present invention has the capacity of spraying in any direction
independent of container orientation and is stable, safe, and predictably uniform
independent of atmospheric pressures and compositions or gravitational forces, being
capable of operation, for example, even in space or under water.
[0016] It is believed that it is a feature of the present invention that the impact does
not generally advance the product mass within the container for expulsion through
the discharge passageways. Rather, it is believed that the fixed wall generally retains
the product mass from instantaneous movement so that the momentum of the impact mass
produces primarily pressure head within the product mass which is recovered or converted
to velocity head at the free surface of the product exposed through the discharge
passageway. Hence, the direction of opening of the discharge passageways (i.e., their
axes) need not be in line with the path of travel of the impact mass at the time of
its impingement against the moveable wall or follower and the moveable and fixed walls
need not be parallel. Discharge at right angles to the direction of impact is even
possible. It also appears to be a necessary feature of the present invention that
the total discharge passageway cross-sectional area be substantially smaller than
the area of the moveable wall or follower.
[0017] The noodles or cluster of particles formed by the dispenser travel ballistically
generally generally normal to the fixed wall outwardly of the container. With proper
selection of product formulation and energy levels of plurality of uniform discharge
passageways may produce a generally uniformly moving cluster of generally uniformly
defined and moving particles with minimal inhalables. The cluster of particles may
be aimed toward a target surface and the deposition pattern thereon may, by proper
selection of energy and product, define a projection of the discharge passageway pattern
selectively comprising either a discrete projection of the individual discharge passageways
or a generally uniform coverage of the passageway locus set. The fixed wall may be
generally planar, whereby the particles of the cluster will move along generally parallel
paths or maybe selectively generally concave or convex with the passageway axes converging
or diverging whereby the particle paths will generally converge or diverge, respectively.
[0018] A specific, preferred embodiment of the present invention comprises a hand holdable,
hand operable non-contact dispenser for and in combination with a stable, non-crusting
anhydrous, thixotropic antiperspirant cream to provide metered and uniform non-contact
spray applications thereof to axilla surfaces without, in general, imparting any undesirable,
cold, wet or sticky sensation.
[0019] The preferred embodiment uses one light follower as the moveable wall impacted by
a single heavier hammer-like-impact mass accelerated by a spring and freely moving
when it strikes the moveable wall. Multiple orifices or discharge passageways are
provided in the fixed wall to dispense a single product dose. Multiple followers/cylinders
each with individual or multiple orifices or discharge passageways also are feasible
for dispensing a single dose in accordance with this invention.
[0020] No breakup is required of the particles after they leave the discharge passageways
of the fixed wall. The target pattern is achieved by virtue of the geometric orientation
of the discharge passageways. One primary spot of product shows up at the target for
each discharge passageway. The size of the spot is a function of the size of the passageway
orifice, the pressure pulse, and the product properties. Particle breakup may, however,
occur.
[0021] The critical requirement of this dispensing mechanism is the pressure pulse created
by the impact. Without the rapid cut-off nature of the pressure pulse, the product
might not break away from itself at the exit orifice of each passageway. The noodle
extrusion must be accelerated and then decelerated fast enough to allow the inertia
of the product outside the orifice to break away from that still in the passageway
and to then continue traveling on to the target. The larger the particle of product
and distance between orifice and target, the greater the energy that must be transferred
to the product from the impact. The major portion of the product within the container
remains essentially static and it is believed that only a pressure wave is transmitted
through the product, to be converted to velocity only at the product surface portions
exposed through the generally open and unobstructed discharge passageways in the preferred
embodiment.
[0022] Product forms other than a thick, rigid cream can be dispensed with the methods and
from the apparatus of the present invention. However, dry powders and runny creams
might not be easily retained in the orifices or discharge passageways, except by auxiliary
retention or closure means.
[0023] The properties of the product must obviously fit this dispensing approach. The product
must be rigid enough to prevent flow out of the orifice or discharge passageways prior
to the application of the pressure pulse. It should be resistant to deterioration
or changes of properties when exposed to air at the discharge passageways since they
are generally open and unobstructed. Of course, a protective overcap or other closure
means may be provided to be removed or opened manually or automatically, without departing
from the present invention. The products' surface tension, viscosity, yield point,
and related properties should allow it to be extruded and separated with a minimal
energy input. The product should also, when designed to be deposited on a target surface,
adhere to the target surface, preferably without rebound.
[0024] In the preferred embodiment of the apparatus of the present invention, a compression
spring is manually cocked and triggered by a single user motion to accelerate the
hammer-like impact mass. Alternative energy sources may include compressed gases,
explosive caps, electric solenoids, magnetic fields, and other spring configurations.
Also, the follower or moveable wall which rests against the product could be a diaphragm.
[0025] While no breakup of the product particles is required after they leave the dispenser
to provide a spray-like delivery, high speed photographs have revealed that, in fact,
with real products the tenacity and cohesiveness result in the noodles extruded remaining
attached for a finite time to the product remaining in the discharge passageways,
with the connecting product stringing out finer and finer until it breaks apart into
small generally uniform particles trailing behind the larger noodle droplets. None-the-less,
few inhalable droplets are formed and, with proper product, dispensers, and energy
level selection, there is no explosion or shattering of any product droplets and substantially
all of the extruded product remains in the ballistically travelling cluster which
also, in general does not diverge into a cone as would occur with conventional spray
nozzles, unless the dispenser is specifically designed to provide divergence. The
discharge passageways may be generally cylindrical or may be slightly divergent or
convergent and the fixed wall may be, if desired, generally concave or convex rather
than generally planar and/or the passageway axes may also converge or diverge.
[0026] It also appears, in general, that if a uniform nonexpanding cluster of particles
is desired and the effective prevention of inhalables, the product should be devoid
of any trapped gas or other relatively compressible elements, since they would tend
to explode the product noodles upon their being extruded from the discharge passageways,
disrupting the spray pattern and dissipating the impulse energy. In addition, for
the application of products to a skin surface, obviously the product particle velocity
should be sufficiently low as to be not uncomfortable when the particles strike the
skin.
[0027] It is an important feature of the present invention that the amount of product dispensed
at each actuation is uniform and constant, depending upon the impact energy of the
hammer-like impact mass when it strikes the follower. Hence, if the hammer-like impact
mass is accelerated by a uniform spring force, for example, with a uniform spring
compression for each actuation, and allowed to then freely travel for impact with
the moveable wall of the canister, its impact energy will be independent of the depth
of product within the canister and a uniform metered quantity of product will be dispersed.
[0028] It also appears to be an important feature that the fixed wall retain the bulk of
the product mass against movement. Hence, the total cross-section area of the discharge
passageways apparently must be substantially less than the area of each of the fixed
wall and the moveable wall or follower. Also, since pressure is believed to be the
primary energy transfer medium within the product, the fixed and moveable walls need
not be equal in area nor parallel in orientation. Discharge even at right angles to
the direction of impact is even possible.
[0029] The invention will now be described with reference to the annexed drawings, in which:
Figure 1 is a perspective illustration of a spray dispenser incorporating the principles
of the present invention;
Figure 2 is a perspective illustration of the spray dispenser of Figure 1 illustrating
the operation thereof;
Figure 3 is an enlarged cross sectional illustration taken along line 3-3 of Figure
1;
Figure 4 is an enlarged cross sectional illustration similar to Figure 3 at the instant
immediately following actuation;
Figure 5 is an end view taken along line 5-5 of Figure 4;
Figures 6 and 7 are partial cross section views similar to FIG. 4 of modified dispensers
in accordance herewith, providing diverging and converging spray patterns;
Figures 8 and 9 are photographs of two exemplary surface deposition patterns achieved
by spraying semi-liquid products with the methods and apparatus of the present invention
ballistically onto target surfaces;
Figures 10, 11 and 12 are graphs illustrating various characteristics of the operation
of the present invention; and
Figures 13, 14 and 15 are sequences of high speed photographs showing the mode of
operation of the spray dispenser of the present invention, utilizing different combinations
of product formulation and discharge passageway configurations.
Detailed description of a preferred embodiment
[0030] With reference now to the drawing, and particularly to FIGS. 1-5 thereof, there is
shown and illustrated a spray dispenser embodying the principles of the present invention
and designated generally by the reference character 10. The dispenser 10 preferably
comprises means for containing a quantity of product for measured spray dispensing
such as a product canister 12 structurally associated with energizing means for accelerating
an impact mass for impact thereagainst to induce a pressure pulse within the product
and thereby spray dispense a metered quantity of product therefrom. The dispenser
10 may, without departing from the broader aspects of this invention, be of substantially
any desired shape, size and configuration commensurate with the product to be dispensed,
the metered quantity thereof to be dispensed by each impact pulse, the number of charges
or metered quantities to be delivered before refill or replacement is required, the
level of the energy per pulse required, the size of the spray pattern desired, the
distance the spray must travel, the discharge velocity desired, the cycling rate desired,
and the like. Moreover, the dispenser 10 may be substantially self-contained, wherein
the container is normally substantially emptied before being refilled or replaced
or may be connected with a supplemental product source wherein product may be essentially
continuously supplied to replenish the supply in the product canister 12 or from which
make up quantities of product may be supplied intermittently, such as, .for example
following each discharge cycle.
[0031] Moreover, the means for accelerating the impact mass may also be designed for relatively
infrequent actuation, as for consumer product dispensing, or for highly repetitive
actuation, as by shop air, power lines, or the like, as for foreseeable commercial/industrial
segment applications, even including high speed multiple operation per minute cycling
providing substantially uninterrupted spraying of product material.
[0032] In accordance with a preferred embodiment, however, the dispenser of the present
invention is especially applicable to the consumer sector spray dispensing of a novel
cream antiperspirant product where generally only a single daily dose application
from a single or a few actuations per axilla is generally what is desired.
[0033] For such use the dispenser should be comfortable to be hand held, directed, aimed
and actuated by a typical consumer. As such, the dispenser 10 should not, in general,
exceed about 15-20 cm in length, about 4-6 cm across the grip area, and about 1 kg
in weight, with the impact mass delivering an energy pulse not exceeding about 2,306
to 3,460 cm.g.
[0034] Being designed to enable the exemplary dispenser 10 to be hand held, the means for
supplying the impact impulse may conveniently, as shown, comprise an energizing helve
14 (the term helve being used to indicate that it functions as fully half the dispenser,
providing a grip portion as well as mechanical utility). The helve 14, in turn, carries
a hand actuable trigger 16 moveable between a normal, unactuated position shown in
solid lines in Figures 1 and 3 and phantom lines in Figure 2 and an inwardly depressed
actuated position, shown in solid lines in Figures 2 and 4. Inward movement of the
trigger 16, as by being hand squeezed by a user, is effective to product a spray or
cluster 18 of product particles ballistically ejected from the product canister 12,
as schematically illustrated in Figure 2 and as photographically shown in FIGS. 13,
14 and 15. The spray or cluster 18 of particles of product in general comprises sets
of primary and secondary product particles designated 20 and 22, respectively.
[0035] The product canister 12 may comprise a generally rigid annular side wall 24 defining
a generally cylindrical bore 26 closed at a forward end portion by a substantially
rigid fixed wall 28 provided with at least one and preferably a plurality of generally
open and unobstructed discharge passageways 30. Slidable within the bore 26 in spaced
apart relationship to the fixed wall 28 there is provided a moveable wall or follower
32 to define within the canister 12 a product chamber 34 which may be filled with
a quantity of semi-liquid product 36. While the moveable wall or follower 32 is slidable
within the bore 26, it should have a tight enough fit to minimize product leakage
between the side wall 24 and the follower 32. In practice, a 0,3 mm diametral gap
appears satisfactory for use with antiperspirant creams as hereinafter described.
[0036] In the dispenser 10 of FIGS. 1-5, the fixed wall or orifice plate 28 is generally
planar so that the particles of product as they move generally perpendicularly outwardly
thereof move along generally parallel paths, without diverging as would occur in conventional
spray mechanisms. However, the spray may, if desired, be made to converge or diverge
by making the fixed wall 28 outwardly concave or convex and for the passageway axes
otherwise convergent or divergent, respectively. Hence, and with reference to FIGS.
6 and 7, there are shown and illustrated, respectively, modified product canister
12' and 12" having an outwardly convex fixed wall 28' with outwardly divergent passageways
30' and an outwardly concave fixed wall 28" with outwardly convergent passageways
30", from which the product will be dispensed in a generally diverging and converging
spray pattern, respectively.
[0037] A "semi-liquid" product, as used herein, both in the description and hereinafter
in the claims is intended to be used to describe products that can be satisfactorily
spray dispensed with the apparatus and process herein described to define a metered
cluster of ballistically ejected generally uniformly defined and formed particles,
as herein described, disclosed, illustrated and shown. Quantitative descriptions of
the properties leading to prediction of successful results, as defined by the quality
of particle uniformity in size and trajectory, have not yet been achieved. Representative
products that are successful are disclosed herein, but it is not the intention hereof
to limit the scope of the present invention, in its broader aspects, to any particular
product formulation.
[0038] Suitable "semi-liquid" products are, in general, thick or viscous so that they exhibit
little tendency to run or flow under gravitational attraction and therefore preferably
do not flow out of the generally open and unobstructed discharge passageways 30 until
the pressure pulse is induced by, for example, the energizing helve 14 and then, only
the desired metered quantity of product is ejected from the generally open and unobstructed
discharge passageways as is determined by the magnitude and duration of the pressure
pulse induced in the product by the impact mass. antiperspirant compounds are set
forth hereinafter. In addition, tests by which "semi-liquids" may be easily identified
are hereinafter described and disclosed. While in its preferred embodiments the invention
sprays a uniform cluster of a semi-liquid product the invention is not limited thereby,
however, and in its broader aspects may be used to dispense other flowable materials
which do not form uniform product. droplets, such as products which do explode or
break up after or during exit from the discharge passageways.
[0039] The canister 12 may be sold or supplied as a disposable package, sold or supplied
pre-filled with the product 36. Alternatively, the canister 12 may be refillable.
To enable the canister 12 to be sold or supplied pre-filled and to enable quick and
easy replacement thereof, the end portion of the side wall 24 generally opposite the
fixed wall or orifice plate 28 may be provided with means, such as internal screw
threads 38 for providing removable attachment of the canister 12 to the energizing
helve 14.
[0040] The forward and rearward faces of the movable wall or follower 32 may be provided
with counterbores or recesses 40 and 42, respectively. The side wall 24 may be extended
generally forwardly of the forward wall or orifice plate 28, as shown, to provide
an annular rim portion 44 surrounding the openings of the discharge passageways 30,
enabling the spray device 10 or the product canister 12 to be placed on a table or
other surface resting on the annular rim 44 with the forward wall or orifice plate
28 being raised therefrom.
[0041] The energizing helve 14 provides support for the canister 12 enabling the spray device
10 to be hand-held and actuated for spray ejection therefrom of the metered quantity
of product constituting the cluster 18 of product particles. The dynamics of the helve
14, together with the diameter and mass of the moveable wall or follower 32, determine
the magnitude and duration of the pressure pulse and, dependent upon the product characteristics
and size and number of discharge passageways, the quantity of product ejected. The
generally cylindrical configuration of the helve 14 also enables the dispenser 10
to be aimed or directed for the ballistic delivery of the cluster 18 of particles
20 and 22 which are discharged from the generally open and unobstructed discharge
passageways 30 in a spray pattern determined primarily by the size, number and pattern
of the open and unobstructed discharge passageways 30 across the fixed wall or orifice
plate 28 relative the magnitude of the pressure pulse induced and the product characteristics.
In the illustrated embodiments, the fixed wall 28, 28' and 28" are generally transverse
the longitudinal axis of the helve 14 and, particularly, the handle portion thereof.
Since, however, it is believed to be primarily pressure, rather than velocity that
is transmitted through the product from the follower 32 to the fixed wall 28 (or 28'
or 28"), the fixed wall need not be parallel the follower 32 nor even transverse the
helve 14.
[0042] While it is not our desire to be limited to any specific theory as to how the pressure
pulse is absorbed by the product, nor as to how it travels through the product to
extrude the product at high velocity from the discharge orifices or passageways, it
appears that when the light-weight moveable wall or follower 32 is impacted, the pressure
pulse is transmitted through the product to the portion thereof filling the passageways
in the fixed wall 28. As the yield point of the product is exceeded, noodles are extruded
from each discharge passageway 30 for the duration of the pressure pulse. As the noodles
stop extruding, the portion of each noodle no longer confined by the discharge passageway
walls breaks away from that portion still within the discharge passageway 30. The
short noodles or particles then ballistically traverse the air between the orifice
plate or fixed wall 28 and the target (if any) with essentially no change in direction,
except due to gravitational and windage forces.
[0043] When multiple discharge passageways 30 are used, no breakup is required of the particles
after they leave the orifice plate or fixed wall 28. The target pattern is achieved
by virtue of the geometric orientation of the passageways across the orifice plate.
One primary spot of product shows up at the target for each passageway. The size of
the spot is a function of the size of the passageway, the product characteristics,
the energy transfer, and the relative sizes and masses of the impact mass and the
follower.
[0044] The larger the diameter of the canister the heavier the follower or moveable wall
32 generally are the more flexible are the canister or container walls and the orifice
plate or fixed wall 28.. The follower or moveable wall 32 are generally heavier, not
only because of the diameter, but also because larger diameters require longer sidewalls
to prevent cocking.
[0045] Not only has the characteristics of the product necessary for optimal spraying not
yet yielded to mathematical analyses such that optimization could be predicted accurately
without trial and error, but also have the energy requirements failed to yield to
accurate mathematical prediction. However, some generalization can apparently be made.
Hence, if it is the pressure pulse in the product that determines delivery rate and
how well it breaks away from the passageways and remaining product, then for maximum
product discharge for a given energy level it is believed advantageous to induce the
highest pressure pulse possible.
[0046] Impulse generated force is a function of the time of impact for a constant energy
level. It is this force which establishes the pressure pulse. P = F/A. Thus, the lower
the area of the moveable wall or follower 32 for a given impulse, the higher will
be the magnitude of the pressure pulse.
[0047] The heavier the product moveable wall or follower 32 the slower it will accelerate
and therefore the longer the time of the impulse and lower the forces creating the
pressure pulse.
[0048] Flexibiity of the canister acts to dampen the pressure pulse. The smaller the canister
the more rigid it is.
[0049] From the above reasoning, it was speculated that a smaller diameter follower will
require less impact energy to deliver the same amount of product per impact and with
the same breakaway characteristics.
[0050] This was verified as follows: a 6 cm. ID canister and a 4 cm. ID canister were fabricated
both with the same wall thickness, same orifice pattern, and same depth of product.
These canisters were subjected to impact by drop testing of a weight against followers
of the same diameter as the canister bore (inside diameter) using a common weight
and height. The delivery rate from each canister was measured.
Example II cream is the product described in detail hereinafter in Example II at page
43 and with reference to Figure 12.
[0051] The delivery from the smaller diameter canister was, therefore, 270% of that from
the larger canister.
[0052] The ratio of areas is
[0053] Thus, it would be predicted that the pressure pulse in the small canister would.be
214% of the pressure pulse in the large canister and the delivery from the small canister
would be 214% of the delivery from the large canister. The delivery is actually 270%
for the small canister, somewhat greater than the theoretical value. This is believed
to be at least partly explained by the fact that the larger diameter canister had
more flexible walls to absorb some of the pressure and a larger follower weight to
reduce the impulse generated force.
[0054] In general, the experiment did confirm that follower diameter affects the delivery
rate as was postulated. The smaller the follower, the greater the delivery per impact
when all else is constant. In addition, the differing velocities and product delivery
rates resulting in significant changes in the deposition of the product on the target
surface.
[0055] Figures 8 and 9 are photographs, essentially full size, of the product deposition
pattern resulting on a black target surface from each of the two trials described
immediately hereabove.
[0056] FIG. 8 shows the deposition pattern from the 6 cm. diameter canister. It may be readily
seen that a single small primary spot of product essentially appears for each of the
45 discharge passageways. Hence, the deposition pattern defines a projection of the
discharge passageway pattern providing a discrete projection of the individual discharge
passageways.
[0057] FIG. 9 is a similar photograph which shows the product deposition pattern from the
4 cm. diameter canister. As can be seen, the deposition pattern also defines a projection
of the discharge passageway pattern and one single primary spot of product essentially
appears for each of the discharge passageways. However, the product spots are seen
to be much larger, apparently because of both the increased product delivery rate
per discharge passageway and the probably increased velocity of the product particles
at impact on the target. Hence, while the distribution of the spots still corresponds
to a projection of the discharge passageway pattern, on the target the spots have
each spread to partially overlap and merge to provide a generally uniform coverage
of the passageway locus set.
[0058] Passageway cross-sections other than round can be used, and slots have successfully
dispensed product. However, the use of slots rather than round holes is not as satisfactory,
the resulting spray pattern lacking the uniformity resulting from round holes.
[0059] An additional study was conducted to determine product delivery rate (volume/impact)
and repeatability under controlled energy delivery. The impact energy was provided
by dropping a weight through a known distance. Since potential energy of an elevated
weight is WH, where W=g. and H=cm., then E=cm.g. of energy. The weight measured 83.5
gm. The drop height varied from 20 cm. to 60 cm. The canister and follower were 5.7
cm. in diameter.
[0060] Experiment 1: The weight was dropped from a 20 cm. drop height five times and sprayed
product collected on the same tared card. The card was weighed after each drop and
recorded. Energy developed per drop from 24 holes 0.16 cm. diameter x 0.32 cm. long
was calculated to an average weight per shot of .22 gm. ± .01 gm. and each impact
was within 5% of this value.
[0061] Experiment 2: The weight was dropped from several heights. The energy developed for
each impact was calculated and the product sprayed in each impact was collected on
a separate tared card which was weighed. The amount of product delivered at each energy
level for each drop from 24 holes 0.16 cm. diameter x 0.32 cm. long using the formula
of Example II hereafter (Page 13) is as shown in the following table and in the graph,
FIG. 10.
[0062] On tests 3 and 4, rebound was evident to a large degree. The product had bounced
off the cardboard target onto the device's orifice plate and skirt. Hence, the high
end of the graph of FIG. 10 is skewed towards the left to an unknown degree, but increased
energy input clearly results in increased product being dispensed.
[0063] In FIG. 11, there is shown a graph wherein delivery rate utilizing the same dispenser;
(i.e., 24 holes, 5.7 cm. diameter canister) is compared against hole length. The energy
pulse was supplied by a falling 83.5 g. weight dropped 28 cm. The hole diameter was
0.16 cm. The curve indicates that, at least for this product, for maximum delivery
for a given energy input, the orifice or passageway length should be kept as short
as possible since, at larger ratios, the amount of product dispensed decreases markedly.
The product was that of Example III, described in detail hereinafter, page 13. The
graph also shows that, since product delivery weight can be affected by the length
of the discharge passageway, variations in passageway length can be used to provide
a mechanism for effecting varying delivery rates for the same energizer and product.
[0064] In FIG. 12, the same product (i.e., Example III) the same dispenser and same impulse
input was used to plot the delivery rate through 24 passageways of 0.165 cm. lengths
with differing diameters. The graph shows a nearly perfect linear relationship between
hole diameter and grams delivered.
[0065] As heretofore pointed out. substantially any flowable product may be dispensed using
the present invention providing only that it can be retained in the container and
discharge passageways; that is, it will not run or leak from the unit when not actuated.
The limits of flowability, wherein the product will break away from the unit and fly
to the target area when actuated yet will not run or leak from the unit when not actuated,
are hard to define on an absolute basis, since factors other than simple viscosity
seem to be important. As a guideline, however, and bearing in mind the preferred embodiment
wherein the dispensers of the present invention is to be hand held and actuated, discharge
passageway diameter between about 0.018 and 0.318 cm., were judgementally assumed
to be about the minimum and maximum diameters at all consistent with hand held, hand
actuated dispensing. With these discharge passageway diameter limits, some guideline
limits of flowability can be defined, using some exemplary fluids.
[0066] Hence, for example, a lower limit was defined by using various dimethylpolysiloxane
fluids furnished by Dow Corning Corporation under the trademark Fluid 200. The least
viscous one of these fluids which did not flow from the discharge passageway during
static conditions had a kinematic viscosity of about 26.4 centistokes as designated
by Dow Corning and as determined by Dow Corning Corporate Test Method CTM 0004 dated
July 29, 1970 entitled "VISCOSITY - Glass Capillary Viscometer" and available from
Dow Corning Corporation, Midland, Michigan. The test measures the time required for
a fixed volume of sample to pass through a calibrated glass capillary using "gravity-flow"
and interpolates the time to the times of fluids standardized according to ASTM D2162.
The method is based on ASTM D445.
[0067] Various Fluid 200 dimethylpolysiloxane fluids were tested for suitability as to flowability
in a 6.35 cm. diameter canister, with a 0.018 cm. hole 0.05 cm. long, supported statically
with the fluid above the hole. Fluids less viscous than the 26.4 centistoke sample
flowed excessively through the hole. Capillary action caused only a low level of leakage
of the 26.4 centistoke sample. Normal unit orientation (e.g. upright) could presumably
eliminate this capillary leakage action if the hole length exceeded the capillary
rise in that hole. An impulse force within the parameters tested can deliver this
fluid through this hole.
[0068] The upper limit for viscosity of anhydrous antiperspirant cream formulations of the
type described in Belgian Patent No. 854,048 and the hereinafter described examples
was measured by needle penetration and determined to be 46 mm penetration of a 83
mm conical needle with a taper of about 9° and about a .15 mm diameter ball tip under
100 g. loading for 5 sec. (using ASTM D1321-70) for product which can be applied from
a 6.35 cm. diameter piston, with a 0.32 cm. 0.05 cm. long hole, driven by a 23,060
cm.g. impulse. An impact impulse of 23,060 cm.g. is approximately 10 times the energy
of the preferred embodiment and double that of the mechanically unaided person.
[0069] Hence, it is apparent that many combinations of product formulation, impulse, input,
canister size, and discharge passageway size, number and pattern are possible and
that variation in any or all of these factors may produce changes in the spray pattern
and deposition pattern of the product. At the present time, a balancing of these factors
has resulted in a judgmental setting of these parameters, for spraying of an antiperspirant
product cream as set forth hereinafter as Example 11, to define a preferred embodiment
to comprise a canister of 5.7 cm. I.D. with its fixed wall being 0.32 cm. thick and
provided with 120 discharge passageways arranged in a hexagonal array (as shown in
FIG. 5) on 0.4 cm. center to center spacing with each being 0.09 cm. in diameter by
0.076 cm. length and having a 0.24 cm. internal countersink to be actuated by 2,306
cm.g. of energy by a 68 g. hammer against a 13.6 g. follower with a 5.7 cm. outside
diameter.
[0070] With renewed reference now to FIGS. 1-5, the energizing helve 14 has a generally
cylindrical handle portion 46 having a longitudinally extending groove 48 within which
the trigger 16 is hinged, as by a pintle or pin 50. The handle portion 46 is also
provided with a recess 52 providing access to the trigger 16 by the user's hands or
fingers even while the trigger 16 is being depressed to its actuated position, enabling
operation thereof by a simple squeeze motion of a user's hand. A generally longitudinally
extending bore 54 and a generally longitudinally extending slot 56 are provided, the
slot 56 connecting the groove 48 with the bore 54. The groove 48 and slot 56, in addition
to enabling movement of the various actuating elements, also provide vents of the
bore 54 to the atmosphere. Sufficient venting of the various impulse delivering elements
is important to avoid any pneumatic dampening or cushioning.
[0071] The forward end portion of the energizing helve 14 may comprise a hammer cup 57 provided
with a generally circular hole or bowl 58 extending generally perpendicularly inwardly
from the hammer cup front face 60. The front face 60 may be generally perpendicular
the bore 54. The hammer cup 57 may also be provided with an externally threaded shoulder
62 onto which the canister 12 can be assembled. Contained within the bowl 58 of the
hammer cup 57 is slidably disposed a hammer-like impact mass 64 comprising a stem
portion 66. The hammer 64 is freely moveable with the bowl 58 and the stem portion
66 thereof may be slidably guided within the bore 54 for reciprocating movement perpendicular
the hammer cup front face 60. Reciprocation of the hammer 64, guided by the stem portion
66, enables the front face 70 of the hammer 64 to impact against the movable wall
or follower 32 of the cannister 12 to provide the pressure pulse within the product
36 to initiate the spray operation.
[0072] The hammer 64 is provided with a passage 68 extending from the impact face 70 of
the hammer 64 generally longitudinally concentrically through the stem portion 66
thereof. The passage 68 provides both a vent path through the hammer 64 to preclude
any air dampening or cushioning thereof and a channel within which there may be disposed
a hammer return spring 72. The hammer return spring 72 biases the hammer 64 inwardly
of the hammer cup 57 and bowl 58. The hammer return spring 72 exerts, at all times
a return force against the hammer 64 exceeding the weight of the hammer 64 to enable
the dispenser to be operated in any orientation. The hammer return spring 72 may extend
from the passage 68 into the lower end of the bore 54. The hammer return spring 72
may be a helical extension spring having hooked ends, one end which is attached to
a hammer retaining pin 74 extending transversely of the hammer 64 through the passage
68.
[0073] At the other end of the bore 54 of the handle portion 46, there is provided a counterbore
76 terminating at a forward shoulder 78. Within the counterbore 76 there may be reciprocally
contained a slide member 80. The slide member 80 may comprise a lug portion 82 extending
transversely outwardly thereof into the slot 56. The slide 80 also may comprise a
forward driving face 84 which, in the forward most position of the slide 80, may engage
the shoulder 78 of the counterbore 76.
[0074] The hammer 64, including the stem portion 66 thereof, may be of a length substantially
equal to the length of the bore 54 between the hammer cup face 60 and the counterbore
shoulder 78 so that, as shown in Figure 3, when the slide impact face 84 is engaged
against the shoulder 78 of the counterbore 76 the impact face 70 of the hammer 64
is in general planar alignment with the forward face 60 of the hammer ,cup 57 and
spaced apart from the movable wall or follower 32 by the depth of the rearward recess
42 of the follower 32, all as shown in Figure 3, which illustrates the dispenser 10
in the unactuated configuration.
[0075] Behind the slide 80, and within the counter bore 76, there may be provided a mainspring
86 which, as shown, may comprise a helical, compression spring having either plane
or ground ends. The mainspring 86 may be retained within the counterbore 76 by a plug
member 88 held, in turn, by a retaining pin 90 extending transversely therethrough
and into the handle portion 46 on either side of the counterbore 76. The slide 80
may be provided with a central passage 92 in general alignment with passage 68 of
the hammer stem 66. The plug 88 may be of generally cup-like configuration containing
a bore 94 through which the retaining pin 90 may pass. The mainspring 86 preferably
may have an outside diameter slightly less than the inside diameter of the counterbore
76 and greater than the diameter of the slide passage 92 and cup 94 of the plug 88
and a free height generally somewhat more than the distance separating the slide 80
from the plug 88 such that the mainspring 86 will be compressed by rearward movement
of the slide 80. The hammer return spring 72 may pass generally freely through the
passage 92 of the slide 80, generally through the center of the mainspring 86, and
into the cup 94 of the plug 88 so that the lower looped end thereof may be held by
the retaining pin 90.
[0076] The preferred spring energizers for the illustrated antiperspirant dispenser use
a 68 g. hammer 64. However, part of the user input energy never reaches the hammer
64, being absorbed by mechanical losses. The mainspring 86 and slide 80 weight 9 g.
The hammer return spring 72 absorbs additional user input energy depending on whether
the canister 12 is full or near empty.
[0077] Not all of the kinetic energy of the hammer 64 is transferred to the product to create
a pressure pulse of sufficient magnitude to cause a discharge. A pendulum or drop
test cannot accurately simulate this transfer of energy, because tests have also shown
that the rigidity of the head support is extremely important. A hand-held device will
dispense only about half the product of a rigidly supported head. Pendulum and drop
tests simulate only the rigid support. Apparently, the illustrated compression spring
hand-held dispenser allows about half of the impact energy to be dissipated in moving
the hand and arm.
[0078] Similarly, the rigidity of the product head components is important. If the fixed
wall having the discharge passageways 30 is flexible or an inelastic collision occurs
between moveable wall or follower 32 and the hammer 64, significant energy is absorbed
by materials other than the product, thereby reducing the pressure pulse. Flexibility
also apparently allows vibrations or reflected pressure waves in the canister after
impact to extrude a small amount of additional product from the discharge passageways,
simulating poor breakaway.
[0079] The trigger 16, as heretobefore pointed out, may be pivoted within the groove 48
about the pintal or pin 50. There may also be provided a stop pin 96 extending across
the groove 48 to pass through an aperture 98 provided within the trigger 16. The pin
96 may therefore limit outward pivot movement of the trigger 16 to its normal, nonoperative
position, as shown in Figure 3.
[0080] Pivotably carried by the trigger 16, there may also be provided a toggle link 102
pivotably associated with the trigger 16 by means of a link pin 104 and biased for
counterclockwise movement relative thereto, as by means of a link spring 106. The
link spring 106, as shown, may comprise a wishbone spring having a tang portion 108
engaging the toggle link 102, a coil portion 110 surrounding the link pink 104 and
a tail portion 112 engaging the trigger 16. The toggle link 102 may be provided with
a rounded a nose portion 114 which may engage the lug portion 82 of the slide 80 as
shown in Figures 3 and 4. There may also be provided a trip pin 116 extending transversely
of the groove 48 positioned, for example, partially within the slot 56 and cooperating
with the toggle link 102.
[0081] Inward movement or rotation of the trigger 16 will therefore cam the slide 80 rearwardly,
compressing the mainspring 86. Such compression of the mainspring 86 enables the hammer
spring 72 to retract the hammer 64 into the bowl 58 of the hammer cup 56. This rearward
movement of the hammer 64 and slide 80 continues until the trigger 16 approaches its
inmost rotative position substantially completely within the groove 48. At such inmost
rotative position, the forces exerted on the toggle link 102 by the trip pin 116 and
the lug portion 82 of the slide 80 cam the toggle link sufficiently clockwise (as
viewed in the drawing) into a tripped position, shown in solid lines in Figure 4.
The lug portion 82 is thereat released from engagement with the toggle link 102, enabling
the mainspring 86 to accelerate the slide 80 forwardly within the counterbore 76.
The engagement of the impact face 84 of the slide 80 against the rearward face of
the hammer stem 66, maintained by the hammer inertia and the biasing from the hammer
spring 72, accelerates the hammer 64 forwardly with the slide 80 until the impact
face 84 of the slide 80 engages the shoulder 78 of the counterbore 76. The slide 80
will stop upon engagement of the shoulder 78.
[0082] The momentum of the hammer 64 will, however, carry the hammer 64 further forwardly,
as shown in solid lines in Figure 4, against the slight restraining force of the hammer
return spring 72 until the impact face 70 of the hammer 64 knock or impacts once against
the moveable wall or follower 32 of the product canister 12 and ideally transferring
its momentum to the moveable wall or follower 32 and therethrough to provide a single
pressure pulse in the mass of product 36. Ideally, it is believed, although we have
not been able to prove it, this pressure pulse delivered to the product absorbs substantially
all of the momentum of the hammer 64 and generates a single pressure pulse within
the mass of product 36. The single pressure pulse generated within the quantity of
product 34 filling the canister 12 between the moveable wall or follower 32 and the
forward fixed wall or orifice plate 28 then causes expulsion of a metered quantity
of the product 34 outwardly through the discharge passageways 30. In Figure 4 there
is illustrated the product just starting to be ejected through the discharge passageways
30 at the instant of impact of the hammer 64 against the moveable wall or follower
32. Following the single impact and inducement of the pressure pulse the hammer spring
72 returns the hammer 64 to its initial position, as shown in Figure 3, and relieves,
therefore, all pressure from the moveable wall or follower 32 which also has moved
slightly forwardly to decrease the volume within the product canister or container
12 by an amount equal the volume of the product 36 dispensed. Release of the trigger
16 allows the trigger spring 106 to re-set the trigger 16 and toggle link 102 for
another operation.
[0083] A removable protective cap 120 having an annular skirt portion 122 and vent means,
such as a vent hole 124 may be provided to protect the product 34 against excessive
exposure to the air. The vent hole 124 prevents any pressure differential developing
during assembly or storage across the product mass 30, the back of the moveable wall
or follower being in turn, as heretofore detailed, vented through the helve 14.
[0084] The dispenser 10 can be repetitively operated in the above manner until the product
36 is substantially entirely exhausted from the product canister 12 and the moveable
wall or follower 32 has moved forwardly into engagement with the fixed wall 28. Experience
has shown, however, that as the moveable wall or follower 32 closely approaches the
fixed wall or orifice plate 28, erratic spray operation results. The reasons for such
erratic operation is not known but it appears to be related to a need for the retention
of sufficient product 36 between the moveable wall or follower 32 and the fixed wall
28 to absorb the impact induced pressure pulse and transmit it uniformly across the
fixed wall 28 and discharge passageways 30. Hence, the moveable wall or follower 32
is provided, as hereinbefore set forth with the forward facing counterbore or recess
40 so that a small amount of product 36 is retained within the recess 40 so as to
be distributed across the fixed wall or orifice plate 28 and across all of the generally
open and unobstructed discharge passageways 30 extending therethrough even as the
moveable wall or follower 32 bottoms out or engages the inside of the fixed wall or
orifice plate 28 annularly around the rim circumscribing the set of generally open
and unobstructed discharge passageways 30.
Example 1
[0085] With reference now to FIGS. 13 and 14, high speed photographs clearly show the spraying
of a cream product from apparatus of the present invention illustrating the mode of
spray formation.
[0086] The cream utilized consisted of the following formulation (by weight):
[0087] Bentone 27 is a hydrophobically treated montmorillonite clay which has a particle
size of below about 5 microns and is commercially available from the NL Industries,
Inc. (formerly National Lead Company). Bentones in general are prepared by reacting
bentonite in a cation exchange system with an amine. Bentonite is a colloidal, hydrated
aluminum silicate obtained from montmorillonite and has the formula AI
20
34Si0
2 . H
20. A more detailed discussion of bentonite can be found in the Kirk-Othmer Encyclopedia
of Chemical Technology, 2nd. Ed., Vol. 3 (1964), pp. 339-360, published by Interscience
Publishers, which is incorporated herein by reference. Bentone 27 is described in
greater detail in technical bulletin F-71-66 from the National Lead Company entitled
"BENTONE 27", which is incorporated herein by reference.
[0088] The cream may be prepared by admixing the isopropyl myristate, cetyl alcohol and
perfume together. The Bentone 27 is then added and mixed with a suitable agitating
device for several minutes to form a uniform composition. The propylene carbonate
may then be added under continued agitation until gellation occurs. Once a thixotropic
gel has formed, particulate aluminum chlorhydrate (having a particle size preferably
from about 1-100 microns, more preferably from about 1-50 microns) may then be blended
into the thixotropic mixture, which may be heated to a temperature of about 50°C.,
and uniformly dispersed and suspended throughout.
[0089] Various types of mixing or agitating means may be employed for preparation of such
a composition. For example, the isopropyl myristate, cetyl alcohol, perfume, Bentone
27 and propylene carbonate can be admixed in a colloid mill or Osterizer to form the
thixotropic gel matrix. Suspension of the aluminum chlorhydrate within the thixotropic
gel can be accomplished by a Hobart mixer or colloid mill.
[0090] In preparing the photographs, FIGS. 13 and 14, the above formulation was spray dispensed
from a canister by impact in accordance with the present invention. Each of FIGS.
13 and 14 comprise a sequence of high speed photographs taken with a HYCAM Model 41-0004
high speed rotating prism camera manufactured by Redlake Corporation of Santa Clara,
California, at 3,000 frames per second on 16 mm movie film. After processing, the
individual movie frames were photographed on 35 mm negative film and alternate frames
were printed to produce FIGS. 13 and 14. Hence, each of the individual frames a-j
in FIGS. 13 and 14 are separated by a time interval of two-three thousandths of a
second or, one fifteen hundredths second equal to approximately six hundred and sixty-six
microseconds.
[0091] In photographing the sequences, the camera was started and then the impulse mass
tripped. In selecting the frame "a" for each of FIGS. 13 and 14, the first frame upon
which product expulsion could be discerned was chosen. The canister end or fixed wall,
which was, in this instance, 5.1 cm. in diameter, can be seen in the lower portion
of each frame. The canister wall was provided with 45 discharge passageways, each
0,114 cm. in diameter by 0.076 cm. length. The impact mass was 66 g. and applied approximately
3,460 cm.g. of impact.
[0092] FIGS. 13 and 14 represent two sequences photographed from slightly differing angles,
FIG. 13 was photographed first, then FIG. 14. From the photographs it can be readily
seen that the product discharge occurs primarily as the extrusion of a slug or noodle
of product substantially simultaneously from each of the discharge passageways. As
the noodle or slug or product is projected outwardly from the discharge passageways
tenaciousness of the product draws a tail behind each primary product slug or particle
which, as is clearly shown in the photographic sequences, are drawn finer and finer
until they break up into secondary clusters of smaller particles trailing behind the
cluster or front of primary particles. As is also clearly shown in the photographic
sequences, the particles do move ballistically along generally parallel trajectories
generally normal the face of the dispenser. It is also apparent that, at least with
this combination of product formulation, discharge orifice size and impact that substantially
only a single pressure pulse provides the noodle extrusion. Other high speed photographs
have, however, on occasion indicated multiple pulses with certain combinations of
product and dispenser for reasons which are not presently understood. In accordance
with our preferred embodiment, however, the uniform single pulse produced cluster
of uniform particles as shown in the photographs is preferred.
Example II
[0093] FIG. 15 is a sequential photograph similar to those of FIGS. 13 and 14 and prepared
in a similar manner. However, the canister has been provided with a fewer number of
discharge passageways, namely, 18. Moreover, a slightly different antiperspirant product,
prepared in the same way as the previous example but having the following formulation
(by weight) was used:
[0094] Comparison of FIG. 15 with FIGS. 13 and 14 indicates some interesting similarities
and distinctions, although the reasons therefore are not known. Firstly, the particle
velocity appears to! be substantially the same. However, the primary; product particles
are much more clearly defined, as is the breakup mechanism for the elongating tails.
The cream extruded in the photographs of FIG. 15 has a substantially higher ratio
of oil to solids wherein the oil is defined as being the total of the isopropyl myristate,
propylene carbonate and perfume with the solids being defined as the total of Bentone,
cetyl alcohol and aluminum chlorhydroxide. Overall, the product formulation and passageway
arrangement of Example II appears to provide a better spray definition than Example
1.
Example III
[0095] Another antiperspirant formulation which has found utility in combination with the
methods and apparatus of the present invention containing the following proportions
of ingredients (by weight):
[0096] Bentone 38 is another amine treated montmorillonite clay similar to Bentone 27 supplied
by N. L. Industries, Inc. It is described in more detail in technical bulletin F-56-67
from the National Lead Company entitled "BENTONE 38", which is incorporated herein
by reference. The Ethanol may comprise SDA 40 (i.e., Specially Denatured Alcohol)
which has been denatured with 0.125% tertiary butyl alcohol or with 1.5 ounce per
100 gallons of brucene sulphate or brucene alkaloid. The cream may be compounded,
for example, similar to the compounding of Examples I and II or may be compounded
by sequentially mixing together at room temperature in, for example, a colloid mill,
a Waring Blender or an Osterizer. The isopropyl myristate and Bentone, then the ethanol,
the propylene carbonate, and finally the aluminum chlorhydroxide and perfume. Bentones
in general must be incorporated with high shear dispersion, but alternatively, the
cream may be compounded in a paddle mixer and be subsequently subjected to the needed
high shear, as by means of a positive displacement pump.