Brush that delivers beneficial agents

A brush having a handle and associated surface application portion, which brush handle contains a beneficial agent generator. The brush typically has a stem with first and second ends, the first end serving as a handle. Bristles are associated with the stem's second end. A beneficial agent generator (such as an electrochemical gas generating cell) that generates a fluid comprising an oxidizing agent is encased within the stem. For treating teeth, the generator will generally be chosen to generate an oxidizing agent such as a peroxide, ozone, oxygen, or mixtures thereof. When the generator requires it, the brush will also include a battery and a switch associated with the stem and in electrical contact with the generator. The switch may be associated with the first stem end and will be in operable (e.g., electrical) contact with the electrochemical gas generating cell and the battery. When the brush is used to brush teeth, it will generally also include a vent or port, in fluid communication with the electrochemical gas generating cell, for venting undesired fluids (e.g., hydrogen gas) from the second end of the toothbrush, such as the first stem end. The invention may be used in various useful methods such as cleaning, bleaching, and sanitizing tooth or other surfaces.

TECHNICAL FIELD 
This invention generally relates to surface treatment devices like brushes, 
especially toothbrushes, adapted to deliver or generate beneficial agents 
for application to a surface, and associated methods useful for treating 
that surface. 
BACKGROUND 
Heretofore, changes in the chemical composition of materials such as 
toothpaste which are to be applied to a surface have been generally 
achieved by modifying the chemical composition itself. Such an approach, 
while adequate for most applications, may be inadequate for certain 
applications where compounds such as highly reactive chemical species 
(e.g., oxidizing agents) are desired to be applied to the surface. If the 
highly reactive chemical species are incorporated into the chemical 
composition itself (e.g., the highly reactive chemical species is 
incorporated into a toothpaste formulation), by the time the chemical 
composition is used, the highly reactive chemical species might already 
have reacted to be reduced or otherwise neutralized. 
It would thus be an improvement in the art to be able to include various 
highly reactive chemical species into a formulation at the time of its use 
(or immediately before the time of its use) so as to allow insufficient 
time for the highly reactive chemical species to decompose or otherwise be 
neutralized in order to achieve more effective treatment of the surface. 
It would also be an improvement in the art to have some means for 
improving a surface treatment compound's penetration into a surface or 
crevices in the surface. 
DISCLOSURE OF THE INVENTION 
The invention includes a brush having a handle and associated surface 
application portion (e.g., bristles), which brush contains or is otherwise 
associated with a particular beneficial agent generator that delivers the 
beneficial agent to the surface application portion of the brush. The 
inventive brush may also be associated with other devices such as an 
ultrasonic wave generator for further enhancing the brush's treatment 
capabilities, especially in the areas of cleaning and disinfection. 
The invention thus includes a brush having a stem with first and second 
ends, the first end serving as a handle. Bristles are associated with the 
stem's second end, and are oriented and affixed to the stem for 
application to, for example, a user's teeth. A fluid generator which 
generates a beneficial fluid comprising an oxidizing agent (such as an 
electrochemical gas generating cell which generates oxygen, ozone, carbon 
dioxide, hydrogen peroide, or mixtures thereof) is encased within the 
stem, which fluid generator is in fluid communication with the bristles so 
as to deliver beneficial fluid to the bristles. An aerating agent, such as 
carbon dioxide might also be generated either by the fluid generator or by 
other means associated with the brush (e.g., utilization of an 
effervescent solution). For bleaching or cleaning teeth or disinfecting 
the gums, the fluid generator will generally be selected to generate an 
agent such as a highly reactive chemical agent (e.g., an oxidizing agent 
chosen from the group of oxidizing agents consisting of peroxides, ozone, 
oxygen and mixtures thereof). 
When the fluid generator requires a separate source of power, as is the 
case with certain electrochemical gas generating cells, the brush will 
also typically include or be operably electrically associated with a 
battery or other power source and a switch or equivalent means for 
activating and deactivating the electrochemical gas generating cell. The 
switch will typically be associated with the stem's first end, and will be 
in electrical contact with the electrochemical gas generating cell. The 
switch may be associated with the stem's first end and will be in operable 
(e.g., electrical) connection with the electrochemical gas generating cell 
and the battery. 
When the brush is used for brushing teeth and the fluid generator is an 
electrochemical gas generating cell, the brush will generally also include 
a vent, in fluid communication with the electrochemical gas generating 
cell, for venting undesired fluids (e.g., hydrogen gas) from the second 
end of the toothbrush, such as the stem's first end. The vent may also 
provide access to the outside atmosphere (i.e., the air) if the particular 
cell used utilizes an outside oxygen source as is the case of a corona 
discharge ceramic cell for generating ozone. 
The invention may be used in various useful methods such as cleaning, 
bleaching, and sanitizing teeth, gingival exteriors or other oral surfaces 
such as the tongue. The oxidizing agents are also known to aid in wound 
healing and, in the case of hydrogen peroxide, bleach teeth. The invention 
thus also includes a method of treating an oral surface involving using 
the aforementioned brush in the form of a toothbrush and brushing the oral 
cavity with the bristles over a period of time (e.g., 30 seconds to 10 
minutes) to treat the oral surface.

BEST MODE OF THE INVENTION 
Referring now to the figures, wherein the showings are for purposes of 
illustrating the invention, and not for the purpose of limiting the 
invention, the figures show a novel and versatile brush. As depicted in 
FIGS. 1 & 2, a preferred device according to the invention, generally 20, 
is shaped similarly to a traditional toothbrush, having a similar length 
and other dimensions. The toothbrush 20 includes a longitudinal stem 22 to 
which at one end is associated (e.g., adhered, molded into, or otherwise 
physically associated with) a series of bristles 24 oriented for 
application to a surface to be treated with the toothbrush 20. 
In the embodiment depicted in FIGS. 1 & 2, the bristle bottoms 26 are 
placed in holes 28 formed (or bored) in the bristle end 30 of the stem 22. 
In the embodiment depicted in FIGS. 1 & 2, positioned underneath the 
bristle bottoms 26 is an electrochemical cell 32 for generating an 
oxidizing gas. Alternatively, the gas generator 32 may be merely in fluid 
communication with the bristle bottoms. The cell 32 is oriented (with or 
without a hereinafter described catalyst) so as to produce an oxidizing 
gas on the surface of the cell 32 proximal the apertures 28 containing the 
bristle bottoms 26. In the depicted embodiment, extra apertures 29 are 
placed in the bristle end 30 of the stem 22 (FIG. 6). These extra 
apertures are not associated with a bristle, and thus allow oxidizing 
agent to pass through the toothbrush stem from the electrochemical gas 
generating cell to an area proximate the bristles 24. A chamber may be 
positioned between said electrochemical gas generating cell and the 
bristle bottoms. In an alternative embodiment (not shown), the bristle 
bottoms do not completely fill the bristle apertures, thus allowing the 
gas containing oxidizing agent to seep pass the bristle bottoms onto the 
tooth surfaces. 
The oxidizing agent generating portion of the device preferably generates 
oxygen electrochemically. In such a case (see, e.g., FIGS. 4 & 5), the 
electrochemical cell will typically include a cathode 48 for reducing 
oxygen in a feed gas to negative ions, neutral species, or mixtures 
thereof; a, for example, Nafion electrolyte 50 for diffusing the negative 
ions, neutral species or mixtures thereof therethrough; and an anode 52 
communicating with the electrolyte 50 for oxidizing the negative ions, 
neutral species or mixtures thereof to produce a high concentration oxygen 
for supply via the extra apertures 29 to the tooth's surface. The 
production of oxygen will typically occur according to a one, two or four 
electron process. The negative ions can be peroxide ions in their various 
protonated and unprotonated forms, superoxide ions including their 
protonated forms, or hydroxyl ions (e.g., if the overall process involves 
the electrolysis of water). 
The oxidizing agent generating device can be of the type that generates 
oxygen according to an electrochemical process which involves a power 
source (e.g., a primary or rechargeable battery) which applies a potential 
difference between the cathode and the anode to concentrate oxygen from 
ambient air which may be introduced via the exhaust port 38 or the 
apertures 29. 
In various embodiments, the oxidizing agent generating portion of the 
device can be the previously described electrochemical cell which 
generates, for example, oxygen, hydrogen peroxide, ozone, or mixtures of 
various components thereof. The oxidizing agent generating portion of the 
device could alternatively be an ozone-generating cell such as the type 
which uses a dielectric (e.g., alumina) powered by, for example, 
batteries. 
Alternatively, and as depicted in FIGS. 7 and 8, the oxidizing agent 
generating portion can be a photoelectrochemical cell 32' whereby water is 
decomposed to generate oxygen and hydroxyl ions or ozone. The 
photoelectrochemical cell 32' incorporates a catalyst 44 (e.g., TiO.sub.2 
or a TiO.sub.2 --NbO.sub.2 solid solution) together with a light source 
(e.g. a lamp 46 such as an ozone producing lamp available from Jetlight 
Company, Inc. of Irvine, Calif. or Light Sources, Inc. of Orange, Conn.) 
which generates an appropriate frequency of light (e.g., from 180 
nanometers to about 1000 nanometers) onto the catalyst 44 in the presence 
of water to generate oxidizing agents wherein the light source (e.g., a 
lamp) is powered by batteries or other power source encased within the 
handle portion 42 (not shown). 
In the embodiment depicted in FIGS. 1 & 2, the electrochemical cell 32 is 
electronically connected with (e.g., by electrical circuitry such as metal 
wires) to a battery 34 or other power source for providing power for the 
electrochemical gas generating cell 32. The battery 34 or batteries may be 
standard batteries, readily commercially available, and are preferably 
rechargeable batteries, such as nickel-cadmium or lithium batteries. 
In the embodiment depicted in FIGS. 1 & 2, electrical circuitry 33 includes 
a switch 36 which interconnects the gas generating cell 32 and the battery 
34 by electrical circuitry. The switch is preferably placed for easy 
actuation by the user. 
Rather than a switch, the toothbrush may be associated with a toothbrush 
holder or other structure having electrodes or other electronic circuitry 
oriented or configured to deactivate the electrochemical gas generation 
cell when the toothbrush is being held by the toothbrush holder or other 
structure, but which automatically actuates the device when the toothbrush 
is removed from the toothbrush holder (not shown). 
In the depicted embodiment, the electrochemical gas generating cell is also 
oriented so that gases which may not be desired (e.g., hydrogen gas), but 
which are nonetheless generated by the electrochemical gas generating cell 
are not exhausted through the apertures 28, but instead are exhausted out 
of an exhaust port 38 which is not intended to be placed within the user's 
mouth. With certain hereinafter described electrochemical gas generating 
cells, the exhaust port may also serve to provide fluid communication 
between the cell and the outside atmosphere which may be needed for the 
cell to work properly. 
In the embodiment depicted in FIG. 3, the stem is made of two portions, a 
bristle portion 40, and a handle portion 42 which interconnect one with 
the other (e.g., by interacting male/female threads associated with the 
respective interacting ends of each portion) in fluid tight relationship 
to form the toothbrush stem. The bristle portion 40 has the bristle end 
30' and means, such as a tubular portion 44 formed in the bristle portion 
40, for providing fluid communication between the electrochemical cell 32 
and the apertures in the bristle portion 40. The electrochemical cell 32 
is oriented in the device of FIG. 3 so as to direct undesired gases out of 
the exhaust port 38; not into the user's mouth. In such an embodiment, the 
bristle portion 40 may be disposable, while the handle portion 42 may be 
reused. 
An electrochemical gas generating cell based on "Nafion" solid polymer 
electrolyte (e.g., a perfluoro sulfonic polymer) may be used. In such a 
case, the electrodes and catalysts on the Nafion are selected so that on 
the portion in fluid communication with the bristles, the chosen oxidizing 
agent will be generated. In an electrochemical cell, oxygen can be 
electrochemically released from a solid anode material of the general form 
A.sub.x O.sub.y as A ions migrate across a suitable ion-conducting 
electrolyte as described in U.S. Pat. No. 5,427,870 to Joshi et al. (Jun. 
27, 1995). Alternatively, electrochemical cells such as those disclosed in 
U.S. Pat. No. 5,454,922, U.S. Pat. No. 5,538,605, or U.S. Pat. No. 
5,593,552 may be used. Generally the reaction proceeds as 4 H.sub.2 
O.fwdarw. O.sub.2 +H.sub.2 O.sub.2 +6 H at the bristle side, while at the 
exhaust side the reaction proceeds as 6 H.fwdarw. 3 H.sub.2 +6 e.sup.-. 
The particular oxidizing agent generated by the cell can be modified 
(e.g., to produce ozone) by modifying the voltage applied to the cell, 
and/or using an appropriate catalyst such as platinum, titania, or lead 
oxide. When such an electrochemical cell is used, a battery is not 
necessary to power the device. 
Alternatively, electrochemical cells such as those disclosed in U.S. Pat. 
Nos. 4,522,698 (June 1985), 4,886,514, and 4,902, 278 (Feb. 20, 1990) to 
Maget et al. may be used in the device, however, in such an instance a 
battery or other power source may be necessary to power the device, and 
the previously described exhaust may be used to serve the dual purpose of 
exposing the cell to the air as well as exhausting undesirable gases. 
Alternatively, another communication port between the electrochemical gas 
generating cell and the outside atmosphere may be formed in the device. 
The production of hydrogen peroxide by electrochemical means is described 
in, among other places, the Comprehensive Treatise of Electrochemistry, 
Vol. 2: Electrochemical Processing, Chapter 3, pp. 167, and 226-250 (New 
York, N.Y., Bockris et al. Editors). 
As identified, a catalyst may be associated with the flow pattern 
associated with the fluid generated by the oxidizing agent generator in 
order to, for example, convert chemicals generated by the generator to 
more desirable agents. Catalysts for scavenging, destroying or degrading 
undesirable chemicals will be chosen according to the particular chemical 
produced by the generator. Examples of catalysts which assist in the 
conversion of a chemical generated by the generator into a more desirable 
chemical compound include gold, graphite powder, or activated carbon. 
Hydrogen peroxide may be synthesized by means of electrochemically reducing 
oxygen in the presence of acid and halide (e.g., bromide) conducted in an 
electrolytic cell (at a cathode). Alternatively, a process such as that 
disclosed in U.S. Pat. No. 5,338,412 to Burk et al. (Aug. 16, 1994) may be 
used to generate a peroxide and/or oxygen with an electrochemical 
generator. 
Rather than using the previously described electrochemical gas generating 
cells, an electrolytic ozone generating device such as that disclosed in 
U.S. Pat. No. 5,326,444 (Jul. 5, 1994) to Nakamatsu et al. or similar 
device may be used as the oxidizing agent generator. Alternatively, a 
proton-exchange-membrane electrochemical flow reactor which simultaneously 
oxidizes and reduces de-ionized water to form ozone and hydrogen peroxide 
at the anode and cathode respectively such as that disclosed in Tatapudi 
et al. "Simultaneous Synthesis of Ozone and Hydrogen Peroxide in a 
Proton-Exchange-Membrane Electrochemical Reactor", J. Electrochem. Soc., 
141(5):1174-1178 (The Electrochemical Society, Inc., May 1994) may be 
modified (e.g., by including a water reservoir within the handle stem) and 
incorporated into the use with the invention. Similarly, other 
electrochemical gas generating cells such as those U.S. Pat. No. 5,427,870 
to Joshi et al. (Jun. 27, 1995). Alternatively, electrochemical cells such 
as those disclosed in U.S. Pat. No. 5,454,922, U.S. Pat. No. 5,538,605, or 
U.S. Pat. No. 5,593,552 may be used (e.g., cells based on copper 
hydroxide) may be used in the device. 
As depicted in FIG. 9, the inventive brush may further include other 
systems, such as an ultrasonic frequency wave generator 54, 56 in 
conjunction with the beneficial agent generator in order to enhance the 
effect of the beneficial agent. In such an instance, a synergistic 
combination may result (e.g., in the areas of cleaning and debriding an 
oral surface). 
In one embodiment, compounds which react to form an effervescent solution 
or other means (e.g., an appropriately structured electrochemical gas 
generating cell) are used to generate carbon dioxide bubbles which pass 
through the bristle or other holes to assist in the permeation of the 
oxidizing agent into the tooth or other surface. 
Other than bristles, other surface application material (e.g., a sponge or 
a pad) may be affixed to the portion of the device to be applied to a 
surface. 
Once being apprised of the instant invention, methods of making and using 
it will become apparent to the ordinarily skilled artisan. For instance, 
the stem (or stem pieces) may be injection molded out of a suitable 
plastic, bristles and their make up are well known to the art, 
electrochemical cells can be as previously described (or their equivalents 
may be used), suitable batteries are readily commercially available, and 
methods of associating the various components of the invention (e.g., 
adhering bristles to a toothbrush stem) are well known. 
Devices according to the invention have the further advantage that even if 
toothpaste is unavailable to the user, some cleaning and anti-microbial 
effect occurs merely do the presence of the oxidizing agent in the 
bristles. 
The invention is further explained by the following illustrative examples. 
EXAMPLES 
Example I 
A device such as that depicted in FIG. 1 is made. It utilizes a battery and 
a switch (available from Radio Shack of Fort Worth, Tex.), a Nafion 
electrochemical oxygen gas generating cell (available from Ceramatec, Inc. 
of Salt Lake City, Utah), a thermoset plastic handle, and flexible plastic 
bristles. The electrochemical gas generating cell utilizes one electrode 
of Pt--Ru while the other electrode is platinum/Ir (see, e.g., U.S. Pat. 
No. 5,454,922 to Joshi et al.). The cell is operated at greater than 1.5 
volts to generate hydrogen and oxygen gas. The hydrogen gas is directed 
away from the bristle area of the brush. Extra holes are formed in the 
bristle portion of the stem to allow oxygen to escape from the gas 
generating cell to the bristles. 
Example II 
The device of EXAMPLE I is actuated by moving the switch to the "on" 
position. The oxidizing agents are generated by the gas generating cell, 
and an oxygen-ozone mixture is formed with the assistance of the platinum 
catalyst. The presence of oxidizing agents is detected proximate the 
bristles. 
Example III 
The device of EXAMPLES I and II is used to brush a subject's teeth, both 
with and without added toothpaste (COLGATE.TM.) in a normal manner (e.g., 
usual times and usual conditions). After time (e.g., three weeks), the 
subject's teeth begin to whiten. 
Example IV 
The device of EXAMPLE I is actuated by moving the switch to the "on" 
position. The oxidizing agents are generated by the gas generating cell, 
and an oxygen-ozone mixture is formed with the assistance of the TiO.sub.2 
catalyst. The presence of oxidizing agents is detected proximate the 
bristles. 
Example V 
The device of EXAMPLE I is actuated by moving the switch to the "on" 
position. The oxidizing agents are generated by the gas generating cell, 
and an oxygen-ozone mixture is formed with the assistance of the PbO.sub.2 
catalyst. The presence of oxidizing agents is detected proximate the 
bristles. 
Although the invention has been described with regard to certain preferred 
embodiments and examples, the scope of the invention is to be defined by 
the appended claims. For instance, although the brush has been described 
as a toothbrush, a brush made according to the invention may be used to 
debride a skin wound.