U.S. patent application number 12/087076 was filed with the patent office on 2009-03-05 for microfluidic surface treatment device.
Invention is credited to Guoping Lian, Georgios Tetradis-Mairis.
Application Number | 20090060622 12/087076 |
Document ID | / |
Family ID | 35841332 |
Filed Date | 2009-03-05 |
United States Patent
Application |
20090060622 |
Kind Code |
A1 |
Lian; Guoping ; et
al. |
March 5, 2009 |
Microfluidic Surface Treatment Device
Abstract
The present invention relates to a microfluidic surface
treatment device which delivers a precise quantity of at least one
functional flowable compound. The device is provided with a
reservoir, a microfluidic device comprising microchannels, and a
pump able to pump the functional flowable compound through the
microchannels. The pump is controlled by a microprocessor. The
device can be a toothbrush, an electric toothbrush, a razor, an
electric razor or a household cleaning device.
Inventors: |
Lian; Guoping; (Sharnbrook,
GB) ; Tetradis-Mairis; Georgios; (Sharnbrook,
GB) |
Correspondence
Address: |
UNILEVER PATENT GROUP
800 SYLVAN AVENUE, AG West S. Wing
ENGLEWOOD CLIFFS
NJ
07632-3100
US
|
Family ID: |
35841332 |
Appl. No.: |
12/087076 |
Filed: |
December 18, 2006 |
PCT Filed: |
December 18, 2006 |
PCT NO: |
PCT/EP2006/012324 |
371 Date: |
June 25, 2008 |
Current U.S.
Class: |
401/28 |
Current CPC
Class: |
A61C 17/3445 20130101;
A46B 11/002 20130101; A61C 19/066 20130101; B26B 19/40 20130101;
A46B 15/003 20130101; A46B 11/0082 20130101; A46B 2200/1066
20130101; A47L 13/26 20130101; A46B 11/0006 20130101; A46B 15/0016
20130101; B26B 21/446 20130101 |
Class at
Publication: |
401/28 |
International
Class: |
A46B 11/00 20060101
A46B011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 29, 2005 |
GB |
0526560.8 |
Claims
1. Device comprising a head portion for contacting a surface, a
handle portion, and at least one reservoir for containing a
functional flowable compound, which is connected via a conduit to
the head portion, characterised in that the conduit comprises at
least one microfluidic device and at least one micro-pump, and the
head portion comprises a plurality of hollow fibres protruding from
the head portion to deliver the functional flowable compound, the
plurality of hollow fibres being surrounded by toothbrush fibres
for protection.
2. A device according to claim 1, wherein the micro-pump is (or the
micro-pumps are) controlled by a computer program.
3. A device according to claim 1, wherein the device comprises at
least one microprocessor.
4. A device according to claim 1, wherein the device comprises at
least one external interface.
5. A device according to 1, wherein the device is a handhold
device.
6. A device according to claim 1, wherein the device comprises an
internal and/or external energy source.
7. A device according to claim 1, wherein the device comprises at
least one battery and/or at least one accumulator.
8. A device according to claim 1, wherein the device comprises at
least one removable (replaceable) part.
9. A device according to claim 8, wherein the removable
(replaceable) parts are batteries and/or accumulators, the
containers for the functional flowable liquid, as well as the head
portion (or parts of it).
10. A device according to claim 8, wherein the removable
(replaceable) is the head portion and/or parts of the head
portion.
11. A device according to any of the preceding claim 1, which is a
toothbrush, an electric toothbrush, a razor, an electric razor or a
household cleaning device.
Description
[0001] The present invention relates to a microfluidic surface
treatment device which delivers a precise quantity of at least one
functional flowable compound.
[0002] In many fields of application a precise dosage of a
functional flowable compound is important. The need for precision
can have many reasons, for example it can be that the functional
flowable compound is highly reactive and therefore should not be
provided in dosages, which are too high; or it can be that the
functional flowable compound should be added in a precise ratio to
obtain a good result.
[0003] Furthermore it can be that the functional flowable compound
is expensive so that the correct (that means efficient) dosage is
desirable, because of cost reason.
[0004] Therefore the goal of the present invention is to provide a
system, which allows a good, reproducible as well as variable
dosage of a functional flowable compound.
[0005] Therefore the present invention relates to a device, which
comprises a head portion for contacting a surface, a handle
portion, and at least one reservoir for containing at least one
functional flowable compound which is connected via a conduit to
the head portion, characterised in that the conduit comprises a at
least one microfluidic device and at least one micro-pump.
[0006] By term "head portion" we mean that part of the embodiment,
where the functional flowable compound is leaving the device.
[0007] By the term "handle portion" we mean that part of the
embodiment, where the embodiment is usually held by a user.
[0008] By term "microfluidic device" we mean a system comprising
microchannels. Depending how many reservoirs are present the
microfluidic device can comprise more than one microchannel, which
can be independently from each other (from the reservoir to the
outlet point) or the microfluidic device can have a cross section
by which the functional flowable compounds are mixed.
[0009] By the term "microchannel" we mean channels with a hydraulic
diameter below 1 mm.
[0010] By term "micropump" we mean a pump able to pump the
functional flowable compound through the microchannel.
[0011] The present invention relates to a device, which is able to
produce very precise and reproducible dosage of a functional
flowable compound.
[0012] Furthermore the embodiment according to the present
invention allows providing the functional flowable compound in a
specific sequence. This can be relevant when more than one liquid
is to be used.
[0013] The device is very suitable for applications wherein a small
amount of one (or more) functional flowable compound is used. For
example, when one functional flowable compound serves to start, to
activate or to catalyse a reaction; and/or when the functional
flowable compound is highly reactive.
[0014] The embodiment according to the present invention is also
suitable to provide customized formulations to a user. The
customisation can be realised either by using a specific designed
functional flowable compound, by the use of a specific designed
container (reservoir) or by using a specific computer program,
which controls the micro-pump system.
[0015] Therefore, a further embodiment of the present invention is
a device, which comprises a head portion for contacting a surface,
a handle portion, and at least one reservoir for containing a
functional flowable compound which is connected via a conduit to
the head portion, characterised in that the conduit comprises at
least one microfluidic device and at least one micro-pump and
wherein the micro-pump is (or the micro-pumps are) controlled by a
computer program.
[0016] The computer program can control any parameter, which is
related to the micropump, for example the flow rate, the total
amount of dosing of the functional flowable compound, the sequence
of dosing, the duration of the flow, etc.
[0017] Such a computer program is stored (saved) on a medium, which
is incorporated into the device. Usually a microprocessor, which is
integrated into the embodiment, is used as a control unit for the
pumping system. Such a microprocessor stores the necessary computer
program. Suitable microprocessors are known in the prior art.
Depending on the field of application of the device the kind of
microprocessor can be adjusted, such as for example the physical
size of the microprocessor as well as the capacity of the
microprocessor.
[0018] As already said, the programming of the microprocessor can
control the flow rate of the micro-pump, the duration of the
pumping process, the sequence of the pumping steps. Additionally
the microprocessor can also be used for controlling any other
process, which is carried out by the device according to the
present invention. For example in case that the embodiment is an
electronic toothbrush the microprocessor is also able to control
the movements (vibration) of the brush.
[0019] In case that the device needs specific physical conditions,
such as heating, cooling, pressure, etc. these could also be
controlled by the microprocessor.
[0020] It is possible to use more than microprocessor.
[0021] The programming of the microprocessor can be influenced by
an external interface. The interface serves to allow replacing or
amending the programming of the microprocessor. Any commonly known
interface can be used. The update (amending or replacing) of the
programming can be done by using an external computer. The update
could be done according to commonly known methods, such as using
CD-roms as well as using downloads from the internet.
[0022] As an alternative the device can comprise a microprocessor
which can be reprogrammed without using an external mean. Such a
device should have some kind of a mean by which it is possible to
amend the programming.
[0023] As an alternative it is also possible to use a
microprocessor, which can be replaced easily.
[0024] Due to the fact that the micropump is (or the micropumps
are) controlled by a microprocessor, the functionality of the
device can be easily adjusted to the need and/or desire of any
user. Individual programming of the microprocessor allows it. It is
possible to store more than one profile on a microprocessor, so
that a group of people (for example a family) can use the device
and every member can have an own stored profile.
[0025] Therefore a further embodiment of the present invention
relates to a device as described above, wherein the device
comprises at least one microprocessor.
[0026] Such a device is easy to handle and therefore consumer
friendly.
[0027] Preferably, the device is a handhold device. That means a
user is able to carry the device as such or at least able to carry
or manipulate the device, which usually sliding on a surface (like
a floor treating device). Examples are toothbrushes, razors,
household cleaning devices (for cleaning files, windows, floors,
etc.).
[0028] The micropump can be operated by an internal or external
energy source. A combination of both is possible, too.
[0029] An internal energy source is usually one or more battery
and/or one and more accumulator. Usually the batteries can be
replaced easily. Depending on the kind of device the batteries can
be the ones usually used in household devices (such as AA or AAA
batteries) but also specific batteries used in industrial
devices.
[0030] In case of an accumulator it is possible to use a removable
accumulator or an accumulator which is an integral part of the
embodiment. Therefore for charging, either the accumulator is
charged (when removed) or the whole embodiment is put on a charging
device.
[0031] Therefore a further embodiment of the present invention
relates to a device as described above comprising an internal
energy source.
[0032] A preferred embodiment of the present invention related to a
device, which comprises at least one battery and/or at least one
accumulator.
[0033] The device can also be operated by an external energy
source, which is usually current from an outlet socket. It would as
also be possible to use a generator, external batteries or
accumulators or any other external energy source.
[0034] The embodiment can consist of one piece, which means that a
user is not meant to remove any part of the embodiment.
[0035] Alternatively, the embodiment can consist of one or more
removable parts. The advantage of having removable parts is that
parts which have a short life span can be replaced
independently.
[0036] In a preferred embodiment, the micropump and the
microprocessor are in that part of the embodiment, which is meant
to have a longer life span.
[0037] In general, replaceable parts are usually batteries and/or
accumulators, the reservoirs (containers) for the functional
flowable compounds, as well as the head portion (or parts of it),
depending on the application of the device.
[0038] Preferred embodiments are devices wherein the head portion
can be removed from the device.
[0039] Specifically when the embodiment is a toothbrush then also
the head portion, which comprises the brush should be
replaceable.
[0040] When the embodiment is a razor, then the head portion, which
comprises the blade or blades should be replaceable or at least the
blade or the blades should be replaceable.
[0041] It is obvious that the removable parts should be fixed to
the device in a way that a user can remove them easily without
destroying the device.
[0042] It is possible to use commonly known fixing systems, which
allows fixing and separating the parts without destroying the
parts, or at least the part with the longer life span should stay
intact. Such fixing systems can be screwing, clicking, as well as
fixing by using an external mean.
[0043] A further embodiment of the present invention relates to a
device, which comprises a removable head portion.
[0044] The embodiment can comprise one or more reservoir for
containing a functional flowable compound. The reservoir itself can
comprise one kind of functional flowable compound. The reservoir
can also comprise more than one chamber, so that more than one
functional flowable compound can be stored in one single
reservoir.
[0045] The functional flowable compound can be any compound which
is liquid and which can be pumped through a micropump system. Such
a liquid usually has a viscosity of less than 60 mPas. Preferably,
the functional flowable compounds have a viscosity of less than 30,
more preferably less than 20 mPas, very preferably less than 10
mPas. The viscosity can be determined according to commonly known
methods for example by using a Haake viscosimeter.
[0046] The functional flowable liquid can be or can contain for
example a catalytic compound, an activator, a flavour compound or
flavour formulation, a dye-stuff, toothpaste, shaving cream, an
antimicrobial compound, UV absorber, etc.
[0047] In case that more than one functional flowable compound is
used for a specific use, it is possible that the functional
flowable compounds are not mixed before they are applied to the
surface, which needs to be treated. That can be achieved by either
that they are applied by two separated microchannels, or that they
are applied by the same microchannel but in a sequence (one after
the other).
[0048] It is also possible to mix the functional flowable compounds
before they reach the surface. This can be done by using a cross
section in the microfluidic device system.
[0049] By varying the shape of the cross section it is also
possible to create specific properties of the mixture. Of course
the choice of the functional flowable compounds plays an important
role as well.
[0050] The device (especially the cover of the device) according to
present invention can be produced according to commonly known
methods, such as molding, carving etc.
[0051] The embodiment can be made out of commonly known materials.
The choice of material depends on the use of the embodiment. The
embodiment can comprise more than one material. Suitable materials
are for examples any kind of polymeric material, plastics, gum,
metals, fibre materials, glass fibres, wood, etc.
[0052] The choice of the material is usually directly related to
the function of a part. The cover of a device is often made out of
a polymeric material, where as of course a microprocessor comprises
silica material.
[0053] Therefore it is very common that the device is produced in
parts and assembled at the end of the production process.
[0054] As said before, depending on the use of the embodiment it is
very suitable and commonly known that the embodiment comprises
parts, which can be removed and replaced.
[0055] Usually at least the head portion (or parts of the head
portion) can be removed and replaced. In such a case the head
portion must be fixed to the handle portion.
[0056] Therefore a further embodiment of the present invention is a
device wherein the head portion can be removed.
[0057] Therefore a further embodiment of the present invention
relates to a device wherein parts of the head portion can be
removed.
[0058] In the case that the embodiment is a toothbrush, the head
portion comprising the brush can be replaced. In such a case the
head portion must be fixed to the handle portion in a way that the
parts can be separated easily by a user. This can be achieved by
locking systems known in the prior art or by the locking system as
described above.
[0059] The tooth applicator device of the present invention is
suitable for applying a functional oral treatment material to the
teeth and/or gums. Preferably this is a tooth whitening agent
however it could be another oral treatment such as a gum treatment
agent, a teeth sensitivity agent or a tooth repair agent.
[0060] A reservoir in the device contains the functional flowable
compound. This is fed to the head portion of the device via a micro
conduit having a cross sectional area of less than 1 mm.sup.2,
preferably less than 0.5 mm.sup.2. The compound is pumped to the
head by a micro-pump and therefore the dosing is highly accurate.
The micro-pump is a pump which has a pumping capacity of less than
10 ml/min and has a volume of less than 10 cc. Preferably the
micro-pump has 1 linear dimension which is less than 5 mm. This
enables stacking for multiple reservoirs variants.
[0061] The reservoir can also contain more than one functional
flowable compound in separated chambers.
[0062] When the reservoir is empty it can be replaced or it can be
refilled.
[0063] The current legal maximum concentration of hydrogen peroxide
in the United States is 6.7 wt %. As a result there are many
product which delivery just this amount in a controlled manner.
However none of them have the convenience of a toothbrush. Most of
them are applied by gum shield or teeth strips which are to be left
on for a specified duration.
[0064] Additionally the embodiment of the present invention allows
amending the dosage in case that new limit values are published.
The present invention combines the convenience of a toothbrush with
the effectiveness of a gum shield technique.
[0065] The functional flowable compound in the reservoir is fed to
the head portion of the device via a microfluidic device. Although
the invention is applicable to the presence of a single reservoir,
it is particularly advantageous where there is a second or further
reservoir. A particularly preferred embodiment is the presence of a
reservoir containing a peroxide bleaching agent and a reservoir
containing a catalyst. The invention allows the two reactive
materials to be merged together in a Y-junction in the microfluidic
device and thus do not have time to react together but instead
emerge from the head of the applicator to perform their catalysed
bleaching reaction on the teeth. Another ingredient combination is
an alkaline solution of ClO.sub.2 in one reservoir and an acidic
solution in the other. When brought together these two streams
produce a neutral stream which can deliver a whitening action and
also an antimicrobial action.
[0066] But it is also possible to catalyse or activate the
H.sub.2O.sub.2 by using a specially designed toothpaste.
[0067] The liquid or combination of liquids is fed to the head
portion for delivery to the tooth surface in the mouth. This may be
by a variety of methods, however it is envisaged that a manifold
will be a typical way of achieving this. In one preferred
embodiment, a plurality of hollow fibres will protrude from the
head to deliver the treatment. Preferably they will be surrounded
by other fibres, such as toothbrush fibres to protect them from
physical harm. Preferably such hollow fibres have an internal
diameter of from 100 to 1000 micrometers, preferably from 200 to
700 micrometres.
[0068] A preferred embodiment of the present invention relates to a
device which is a toothbrush. Using a device as described in the
present patent application bleaching of teeth is simplified.
[0069] Bleaching is the most effective method of whitening teeth.
The bleaching compound works by oxidising coloured unsaturated
compounds into carboxylic acids and alcohols. However, because of
their nature, legal limits are imposed on their use. Thus many
commercial bleaching products attempt to work up to the maximum
limit and then accurate dosing becomes critical. Without accurate
dosing any device would have to operate well clear of any legal
limits and thus reduce their effectiveness.
[0070] The accuracy of dosing which microfluidic technology permits
the dosing of bleaching compounds are closer to the legal maximum
than was previously possible.
[0071] Preferred bleaching compound are hydrogen peroxide, sodium
percarbonate peroxide and carbamide peroxide.
[0072] These bleaching materials need to be left in contact with
the teeth for a few minutes.
[0073] It is highly preferred that the bleaching is enhanced by the
presence of a catalyst.
[0074] For peroxide bleaching to be most effective it needs to left
on the teeth for up to 30 minutes. This may be impractical for an
applicator device. Therefore it is preferred that the device also
delivers a catalyst which accelerates the whitening process.
[0075] One preferred catalyst is the iodide ion, which may be
provided for example by potassium iodide. The addition of the
iodide to a peroxide in a basic medium yields free radical oxygen
and water, generating large amounts of heat and depleting the
hydrogen peroxide in a matter of minutes. The free radical oxygen
generated in this reaction can be utilised to oxidise the organic
molecules responsible for staining which causes them to become
colourless and soluble in water. The iodide ion is therefore a
convenient method of providing potent bleaching without the need
for external energy supply such as light, lasers, heat sources
etc.
[0076] Another possible combination is bleaching agent and peracid.
This unstable combination gives excellent whitening when used in
the device according to the present invention.
[0077] The fast catalytic reaction is part of the reason why
so-called whitening toothpastes are less effective than separate
applicator techniques. The present invention permits the use of a
catalyst to give much greater whitening effect but also with the
convenience of a toothbrush applicator.
[0078] The invention will now be illustrated with reference to the
following drawings in which:
[0079] FIG. 1: is a side view of a device according to the
invention. It shows a device having a head portion (1) and a handle
portion (2). The device comprises a reservoir (3) comprising a
functional flowable liquid, which can be pumped out by a micro-pump
(5) into a microfluidic device (4). The functional flowable liquid
then travel through a fine capillary (microchannel) (6), where it
enters a manifold in the head portion and where it is distributed
into different capillary tubes aligned with the fibres (Delivery
point (9) in the head portion. In use the user controls the device
from a control panel which is connected to the electronics board
(8) which controls the micro-pump (5) and optionally a micomechanic
part (15), which can create effect, which can be useful for a
specific use (such vibration, changing temperature etc.). The head
portion can either be removable (replaceable) or non-removable.
[0080] FIG. 2: Is showing is a side view of a device according to
the invention, wherein the head portion (1) is removed from the
handle portion (2). Each part is the same as in FIG. 1.
[0081] FIG. 3: shows a conventional electric toothbrush which has
been modified to deliver a precisely controlled quantity of
whitening peroxide compound. It shows a toothbrush having a head
portion (1) and a handle portion (2). The toothbrush comprises also
a battery (7), which powers a motor (12), which rotates a shaft
which enters a gearbox (13). The output from the gearbox inters an
agitator mechanism (14) which can add translational movement to the
rotational movement. The movement generated is translated to the
chassis of head portion (11) which deans the teeth. The user grips
the toothbrush by the chassis of the handle portion (10). In
addition, the toothbrush contain a reservoir (3) holding liquid
peroxide bleaching compound, which can be pumped out by a
micro-pump (5) into a microfluidic device (4). The peroxide bleach
then travel through a fine capillary (6), where it enters a
manifold in the head and the peroxide is distributed into different
capillary tubes aligned with the fibres (Delivery point (9) in the
toothbrush head, terminating a millimetre or so before the tooth
brush fibres. In use the user controls the application of bleach
from a control panel which is connected to the electronics board
(8) which controls the micro-pump (5) and the motor (7).
* * * * *