GB2309378A

GB2309378A - Toothbrush:electric potential:battery

Info

Publication number: GB2309378A
Application number: GB9701250A
Authority: GB
Inventors: Hiroshi Hukuba
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-01-23
Filing date: 1997-01-22
Publication date: 1997-07-30
Also published as: GB9701250D0; JPH09191936A

Abstract

In a toothbrush in which an electric potential is established via a handle electrode and the bristles as electrodes, to assist plaque removal, a battery is formed integral with the handle to reduce handle size. Handle chamber 39 a encloses negative electrode substance 42 in contact with plate 26, separator 44 and positive electrode substance 41 in contact with hand-contacting electrode plate 32. Plate 26 terminates in a surface cavity immediately before the brush bristles to allow liquid such as saliva to provide electrical connection between the plate and bristles. Battery materials are described.

Description

ION TOOTHBRUSH The present invention relates to an ion toothbrush, and more particularly to an ion toothbrush in which a battery construction is formed within the handle portion of the toothbrush, and which is arranged in such a way that the brushing effect is improved by causing an electrical current to flow between the teeth and the brush bristles.

There have already been various proposals for ion toothbrushes and electronic toothbrushes (which will be referred to generally as "ion toothbrushes" hereinbelow) which effectively remove plaques using an electrical potential gradient. B way of example of ion toothbrushes of this type, there are versions which, for example, are equipped with a head portion in which brush bristles are implanted, a handle accommodating a commercial battery, and a conductive plate fitted to the outside surface of at least one part of the handle portion, and in which one electrode of the battery is configured so as to be able to connect with the brush bristles, while the other electrode is arranged so as to be able to connect with the conductive plate.

Figure 9 shows an enlarged partial cross section of an ion toothbrush which uses a commercial button battery. In this ion toothbrush, a battery-accommodating hole 18 for accommodating a button battery 21 is opened in the surface in approximately the central position in the longitudinal direction of a main body 10. Part of a conductive rod 27, which is provided in the longitudinal direction of the main body 10 and one end of which connects with the brush bristles, is exposed in the floor of this batteryaccommodating hole 18, and the exposed portion is configured in such a way that it is in electrical contact with one electrode (for example the negative electrode) of the button battery 21. Further, the other electrode of the button battery 21 is in electrical contact with a conductive plate 32 via a conductive spring 24. Further, an O-ring 36 which seals the battery-accommodateng hole 18 in a watertight fashion is provided around the upper portion of the batteryaccommodating hole 18. The button battery 21 comprises a positive electrode 21a, a negative electrode 21b, a separator 21c which is interposed between these two and insulates them, a gasket 21d provided around them, and metal plates 21e (outer housing) provided above and below them.

Further, Figure 10 shows an enlarged partial cross section of an ion toothbrush which uses a commercial barlike or pin-like battery. This ion toothbrush also has a configuration in which a bar-like battery 22 is accommodated in a battery-accommodating hole 18 opened in a main body 10.

The positive electrode 22a of the bar-like battery 22 is in electrical contact with a conductive plate 32 via a spring 24, and the negative electrode 22b is in electrical contact with a rod 27. The reference 22c is a separator, 22d is a gasket, 22f is an outer terminal (outer housing), and 22g is a central terminal shaft.

On the other hand, there are versions in which, instead of batteries, metals with different ionization tendencies are respectively provided in predetermined positions in a toothbrush, and an electrical potential difference is created between the two using water, saliva and the like seeping in from the outside. For example, Japanese Patent Publication (JP-B) S38-3220 (1963) and JP-B S53-27984 (1978) disclose ion toothbrushes with different sorts of metals with different ionizing tendencies, in which one such metal is provided in the brush portion and the other is provided in the handle portion. Further, JP-B S4530437 (1970), Japanese Utility Model Laid-open Publication S59-97625 (1984) and Japanese Utility Model Laid-open Publication 559-101722 (1984) disclose ion toothbrushes in which both the different sorts of metals are provided in the brush portion. Again, U.S. Patent No. 407,115 discloses an ion toothbrush in which, by fitting a voltaic pile (a pair of different metals and an impregnated cloth, piled up alternately) with freedom of attachment and detachment on the inside of the handle, this part is used as a galvanic cell.

However, ion toothbrushes which accommodate commercial batteries in the handle need to have a design in which the size of the handle has been matched with commercially available batteries. Consequently, there is a problem in that it is difficult to set the dimensions (diameter) of the handle freely, matched with the requirements of the user. Further, there is also a problem in that it is difficult to reduce the price of ion toothbrushes because it is difficult to reduce the costs of commercial batteries.

Further, with the ion toothbrush disclosed in U.S.

Patent No. 407,115, although a stopper is created from a cap after the voltaic pile has been accommodated in the handle1 there is a risk that this will not have been configured in a watertight fashion and water will seep in from the outside.

Again. there are problems in that, since the size of the voltaic pile is large and this part is free to be attached to and detached from the inside of the handle, the diameter of the handle will inevitably be large and difficult for the user to grasp.

Meanwhile, other ion toothbrushes employing metals with different ionization tendencies have problems in that the electrical potential difference (voltage) which is obtained is small. and it is not possible to obtain a voltage of 1.5 volts or more which is normally required for an ion toothbrush. Now, it has been reported that a voltage of about 1.5 to 3 V is required to obtain good therapeutic effects against gingivitis, effects against periodontal hypersensitivity at the roots of the teeth, effects in removing plaques, effects in improving conditions in the gums, and the like. Further, it has been reported that it is totally safe for the human body to use an ion toothbrush at such voltages even if it is used every day. Consequently, the ion toothbrushes disclosed in the publications mentioned above have problems in that these effects which they should essentially achieve are not sufficiently achieved.

The present invention is intended to overcome such problems of the prior art, and it is an aim of the invention to provide an ion toothbrush which achieves a voltage of at least 1.5 volts and preferably 1.5 to 3 volts as required in an ion toothbrush, is equipped with a simplified and reduced scale battery construction, and in which the size of the handle portion can be set to match the requirements of the user.

In order to achieve this aim, the present invention provides an ion toothbrush comprising an insulating main body, brush bristles implanted in the front end of the said main body, and a battery construction formed integrally with the main body, and in which ion toothbrush one of the electrodes of the said battery construction is configured so as to be able to connect with the brush bristles, and the other electrode is configured so as to be able to connect with the gripped portion of the main body.

The battery construction mentioned above refers to a construction configured so as to be watertight against the outside, and in which at least one portion of the outer housing is constructed from the handle portion.

Further, the battery construction may be arranged in such a way that a positive electrode active substance, a negative electrode active substance and an electrolyte are accommodated in a battery chamber formed in the main body, and the wall of the main body delimiting the battery chamber constitutes part of an insulating mechanism between the positive electrode active substance and negative electrode active substance.

This ion toothbrush can have the first of the electrodes as the negative electrode and the other electrode as the positive electrode. Further, the positive electrode active substance can comprise an oxide, and the electrolytic solution included in the battery structure can be a nonaqueous electrolytic solution.

Preferred embodiments of the present invention will now be described hereinbelow by way of example only with reference to the accompanying drawings, in which: Figure 1 is a cut-away cross section showing an ion toothbrush according to a first mode of embodiment of the present invention, partially cut away in the longitudinal direction; Figure 2 is an enlarged cross section of part of Figure 1; Figure 3 is an enlarged cross section of part of an ion toothbrush according to a second mode of embodiment of the present invention; Figure 4 is a cut-away cross section showing an ion toothbrush according to a third mode of embodiment of the present invention, partially cut away in the longitudinal direction; Figure 5 is a cut-away cross section showing an ion toothbrush according to a fourth mode of embodiment of the present invention, partially cut away in the longitudinal direction; Figure 6 is a cut-away cross section showing an ion toothbrush according to a fifth mode of embodiment of the present invention, partially cut away in the longitudinal direction; Figure 7 is a cut-away cross section showing an ion toothbrush according to a sixth mode of embodiment of the present invention, partially cut away in the longitudinal direction; Figure 8 is an enlarged cross section of part of an ion toothbrush according to a seventh mode of embodiment of the present invention; Figure 9 is an enlarged cross section of part of a conventional ion toothbrush; and Figure 10 is an enlarged cross section of part of a conventional ion toothbrush.

Modes of embodiment of the present invention are now described with reference to the Figures.

(First mode of embodiment) Figure 1 is a partially cut-away cross section of an ion toothbrush according to a first mode of embodiment of the present invention, and Figure 2 is an enlarged cross section of part of Figure 1.

The ion toothbrush shown in Figure 1 and Figure 2 comprises a main body 10 consisting of an insulating material, and brush bristles 12 implanted in the front end of the main body 10.

As shown in particular in Figure 2, in the gripped portion lOb of the main body 10, which is gripped by the user, an accommodating hole 39 of T-shaped cross section in the longitudinal axis is opened facing from the side in which the brush bristles 12 are implanted in the main body 10 (which side is referred to as the 11obverse surface" of the handle hereinbelow) toward the reverse surface. The vertical stroke portion of the letter T of this T-shaped accommodating hole 39 constitutes a battery chamber 39a, and part of a conductive plate 26 provided in a more or less axially central portion in the longitudinal direction of the main body 10 is exposed in the floor of this battery chamber 39a. The battery chamber 39a accommodates, in sequence from the exposed conductive plate 26, a negative electrode active substance 42, an electrolytic liquid holding layer 43, a separator 44 and a positive electrode active substance 41.

The positive electrode active substance 41 is accommodated in such a way that it is level with (the same height as) the upper portion of the battery chamber 39a. In other words, the battery chamber 39a is opened in such a way that it has the same depth as the height of the negative electrode active substance 42, the electrolytic liquid holding layer 23, the separator 44 and the positive electrode active substance 41 when these are piled one on top of the other.

The portions constituting the basic components of the battery such as the negative electrode active substance 42, the electrolytic liquid holding layer 43, the separator 44 and the positive electrode active substance 41 are referred to as the main battery body 50 hereinbelow. An O-ring 36 for keeping the inside of the battery chamber 39a watertight is provided around the outside of the battery chamber 39a.

Meanwhile, a conductive plate 32 is accommodated and secured in a recess 39b constituted by the portion constituting the cross stroke of the letter T. The upper surface of this conductive plate 32 is provided level with (at the same height as) the obverse surface of the main body 10. Here, the negative electrode active substance 42 is in electrical contact with the conductive plate 26, while the positive electrode active substance 41 is in electrical contact with the conductive plate 32. In other words, the conductive plate 26 plays the role of a negative terminal while the conductive plate 32 plays the role of a positive terminal.

Thus, in an ion toothbrush according to the present mode of embodiment, a battery structure 40 is formed in which insulation between the positive electrode active substance 41 and the negative electrode active substance 42 is effected by the separator 44 and the wall of the main body 10 delimiting the battery chamber 39a, and in which the conductive plate 32 plays the role of a lid by the positive electrode active substance 41, and the conductive plate 26 plays the role of a floor plate by the negative electrode active substance 42. In other words, with this electrode structure 40, it is possible to adopt a construction which eliminates, as shown in Figure 9 by way of example, gaskets 21d, metal plates 21e and springs 24 in a battery 21.

Because it is therefore possible to reduce the size of the battery used, compared to the prior art, the size (thickness) of the main body 10 can be reduced. Consequently, it is possible to provide an ion toothbrush equipped with an easily grasped main body 10 suited to the requirements of the user. Further, because it does not use commercial batteries which have greatly affected the price of conventional ion toothbrushes, low costs can be achieved, and, unlike commercial batteries, the battery life can be freely set to match the life of the ion toothbrush (in particular the brush bristles), which is all the more economical.

It should be noted that in the present mode of embodiment manganese oxide was used as the positive electrode active substance and metallic lithium as the negative electrode active substance, while vacuum dried lithium tetra-fluoroborate (LiBF,) dissolved in r -9L distilled under reduced pressure with the insertion of metallic lithium pieces, which is to say a non-aqueous electrolytic liquid (organic electrolyte) was used as the electrolytic liquid. By combining these, one can obtain at least 1.5 V, and preferably about 1.5 to 3 V in a stable fashion. Here, the main battery body 50 portion of the ion toothbrush according to the present invention is watertight to the outside, and it is possible to form a lithium battery of this sort which achieves at least 1.5 V, and preferably about 1.5 to 3 V.

The conductive plate 26 extends inside the main body 10 toward the brush bristles 12 and terminates immediately before the brush bristles 12. As shown in Figure 1, a conduit 14, where the end of the conductive plate 26 is exposed in the obverse surface of the main body 10 in the vicinity of the brush bristles 12, opens immediately before the brush bristles 12. This conduit 14 constitutes part of a liquid pathway which allows the brush bristles 12 and the conductive plate 26 to connect electrically with each other using a liquid such as saliva as the medium.

With an ion toothbrush with such a configuration, when the user grips the gripped portion lOb of the main body 10 while touching the conductive plate 32 with their hand and brushes their teeth with the brush bristles 12, the brush bristles 12 are wetted by liquids such as saliva and the conductive plate 26 becomes able to allow electricity to pass via a pathway linked by liquid which includes the conduit 14. Thus, an electrical current flows from the positive electrode active substance 41 through a pathway constituted by the conductive plate 32, the person's hand, body and teeth, the brush bristles 12 and a liquid path including the conduit 14, the conductive plate 26, and the negative electrode active substance 42. The electrical potential gradient at this time is able to produce a good plaques deposit removlng effect, therapeutic effect against gingivitis, effect against periodontal hypersensitivity, and effect improving conditions in the gums.

(Second mode of embodiment) An ion toothbrush according to a second mode of embodiment of the present invention is now described with reference to Figure 3. It should be noted that, in the present mode of embodiment, parts which are the same as in the first mode of embodiment discussed above have been ascribed the same references, and detailed descriptions thereof have been omitted. The difference between the ion toothbrush according to the first embodiment of the ion toothbrush according to the second mode of embodiment lies in the use of a conductive rod 27 instead of the conductive plate 26, and in the construction of the main battery body 50.

To elaborate, in the ion toothbrush shown in Figure 3, part of a conductive rod 27 provided in a more or less axially central portion in the longitudinal direction of the main body 10 is exposed in the floor of a battery chamber 39a opened in the gripped portion lOb of the main body 10.

The battery chamber 39a accommodates a main battery body 50 in which a thin-film laminate comprising a conductive plastic film 51, a negative electrode active substance 52, a separator 53 and a positive electrode active substance 54 are laminated in sequence from the exposed rod 27, three times over, and in which a conductive plastic film 51 is further laminated on top of these. Like the ion toothbrush discussed above, in this ion toothbrush too, a battery construction 40 is formed in which insulation between the positive electrode active substance 54 and the negative electrode active substance 52 is effected by the separator 53 and the wall of the main body 10 delimiting the battery chamber 39a, and in which the conductive plate 32 plays the role of the lid of the positive electrode active substance 54, and the rod 27 plays the role of a floor plate by the negative electrode active substance 52.

Furthermore, in the present mode of embodiment, manganese oxide was used as the positive electrode active substance and zinc powder as the negative electrode active substance.

(Third mode of embodiment) An ion toothbrush according to a third mode of embodiment of the present invention is now described with reference to Figure 4.It should be noted that, in the present mode of embodiment, parts which are the same as in the first mode of embodiment discussed above have been ascribed the same references, and detailed descriptions thereof have been omitted. The difference between the ion toothbrush according to the first mode of embodiment of the ion toothbrush according to the third mode of embodiment lies in the fact that the main battery body 50 is formed on both sides sandwiching the conductive plate 26, and the fact that the conductive plate 26 extends to the obverse surface of the portion of the main body 10 where the brush bristles 12 have been implanted.

To elaborate, in the ion toothbrush shown in Figure 4, the main battery body 50 and the conductive plate 32 are also formed, in an arrangement which is symmetrlcal relative to the conductive plate 26, on the side of the gripped portion lOb opposite the side where the brush bristles 12 are implanted shown in Figure 1 and Figure 2 (this opposite side being referred to as the "reverse surface side of the handle" hereinbelow). In other words, although not particularly depicted, a battery chamber 39a formed in the reverse surface side of the conductive plate 26 also accommodates a negative electrode active substance 42, electrolytic liquid holding layer 43, separator 44 and positive electrode active substance 41 in sequence from the exposed conductive plate 26, and a conductive plate 32 is accommodated and secured in a recessed portion 39b. The upper surface of this conductive plate 32 is also provided level with (at the same height as) the obverse surface of the main body 10.

The conductive plate 26 extends to, and is exposed at, the obverse surface of the main body 10 where the brush bristles 12 are implanted.

In this ion toothbrush, the part which is exposed at the obverse surface of the main body 10 where the brush bristles 12 are implanted establishes electrical contact by being wetted by saliva and the like, whereas the ion toothbrush according to the first mode of embodiment formed a liquid path which includes the conduit 14.

It should be noted that in this mode of embodiment it is also possible to use the main battery body 40 used in the second mode of embodiment.

(Forth mode of embodlment) An ion toothbrush according to a fourth mode of embodiment of the present invention is now described with reference to Figure 5. It should be noted that, in the present mode of embodiment, parts which are the same as in the first mode of embodiment discussed above have been ascribed the same references, and detailed descriptions thereof have been omitted. The difference between the ion toothbrush according to the first mode of embodiment of the ion toothbrush according to the forth mode of embodiment lies in the fact that it uses the rod 27 used in the second mode of embodiment, and the fact that the main body 10 can be split into a head portion lOa and a gripped portion lOb.

To elaborate, the ion toothbrush shown in Figure 5 is configured in such a way that the head portion iOa in which the brush bristles 12 are implanted is fitted with freedom to be attached to and detached from the gripped portion lOb which is gripped by the user. A rod insertion portion 28 which is opened in such a way that the front end of the rod 27 is exposed from the floor of the conduit 14 is formed in a more or less axially central portion in the longitudinal direction of the head portion lOa. Meanwhile, the rod 27 extends from the side of the gripped portion lOb where the head portion 1Oa is fitted (which side is referred to as the "front end" hereinbelow). Also, the configuration is such that the extended rod 27 is inserted to the desired position in the rod insertion portion 28, and two attachment portions which are not depicted but are formed in the head portion 1Oa and the gripped portion lOb are attached together, thereby fitting the head portion 10a into the gripped portion lOb with freedom of attachment and detachment.

It should be noted that in this mode of embodiment it is also possible to use the battery construction 40 used in the second mode of embodiment.

(Fifth mode of embodiment) An ion toothbrush according to a fifth mode of embodiment of the present invention is now described with reference to Figure 6. It should be noted that, in the present mode of embodiment, parts which are the same as in the fourth mode of embodiment discussed above have been ascribed the same references, and detailed descriptions thereof have been omitted. The difference between the ion toothbrush according to the fourth mode of embodiment of the ion toothbrush according to the fifth mode of embodiment lies in the fact that the rod 27 is divided into a head-side rod 27a and gripped-side rod 27b, and the fact that the shape of the attaching ends of the head portion iCa and the gripped portion lOb (referred to as "base ends" hereinbelow) and the shape of the front end of the gripped portion lOb are different.

To elaborate, in the ion toothbrush shown in Figure 6, a projection ila is formed in the central portion of the base end surface of the head portion lOa. In a more or less axially central portion in the longitudinal direction of the head portion 1Oa, the rod 27a has its front end side exposed from the floor surface of the conduit 14 while its base end side is provided up to a position withdrawn from the baseend surface of the projection lia. More specifically, a rod insertion hole 29 in which the rod 27b on the gripped portion side can be freely inserted is opened in the surface on the base end side of the projection lia. Meanwhile, a recess lib where the projection lia is attached is opened in the central portion of the front end surface of the gripped portion lOb. In a more or less axially central portion in the longitudinal direction of the gripped portion lob, the rod 27b is provided in a state in which its front end portion extends from the central portion of the recess lib.

This extended part of the rod 27b is designed in such a way that it is inserted into the rod insertion hole 29, and comes into contact with the rod 27a, thereby making electrical contact.

This ion toothbrush is configured in such a way that the extended front end of the rod 27b on the gripped side is inserted into the rod insertion portion 29 and two attachment portions which are not depicted but are formed in the projection ila and the recess lib are attached, thereby fitting the head portion 108 into the gripped portion lOb with freedom of attachment and detachment.

(Sixth mode of embodiment) An ion toothbrush according to a sixth mode of embodiment of the present invention is now described with reference to Figure 7. It should be noted that, in the present mode of embodiment, parts which are the same as in the first mode of embodiment discussed above have been ascribed the same references. and detailed descriptions thereof have been omitted. The difference between the ion toothbrush according to the first mode of embodiment of the ion toothbrush according to the sixth mode of embodiment lies in the fact that a conductive plate 32 is provided on the reverse surface side of the gripped portion lOb, and the fact that the conductive plate 26 is provided on the obverse surface side of the main body 10 via the main battery body 50 and an insulating cover 33 is provided on top of this with the front end portion of the conductive plate 26 exposed.

To elaborate, in the ion toothbrush shown in Figure 7, the accommodating hole 39 is opened facing from the reverse surface side to the obverse surface side of the gripped portion lOb. Part of the conductive plate 26 is exposed in the upper portion (the obverse surface side of the main body 10) of this accommodating hole 39. Although not particularly depicted, the battery chamber 39a of the accommodating hole 39 accommodates, in sequence from the exposed conductive plate 26, a negative electrode active substance 42, an electrolytic liquid holding layer 43, a separator 44 and a positive electrode active substance 41, and a conductive plate 32 is provided level with the reverse surface of the main body 10 in the recess 39b.

The front end portion of the conductive plate 26 has a shape whereby it protrudes slightly from the other parts, and the obverse surface of this protruding portion 26a is provided in such a way that it is level with the obverse surface of the main body 10 in the vicinity of the brush bristles 12, and exposed from the main body surface. An insulating cover 33 is provided and secured on the parts other than the protruding portion 26a of the conductive plate 26 in such a way that it is level with the surface of the projecting portion 26a or, in other words, is level with the surface of the main body 10.

(Seventh mode of embodiment) An ion toothbrush according to a seventh mode of embodiment of the present invention is now described with reference to Figure 8. It should be noted that, in the present mode of embodiment, parts which are the same as in the first mode of embodiment discussed above have been ascribed the same references, and detailed descriptions thereof have been omitted. The difference between the ion toothbrush according to the first mode of embodiment of the ion toothbrush according to the seventh mode of embodiment lies in the fact that the battery construction 40 is provided in the base end side of the main body 10, and in the fact that it uses a rod 27 instead of the conductive plate 26, and the configuration of the main battery body 50.

To elaborate, in the ion toothbrush shown in Figure 8, a conductive plate 32 is provided so as to cover the gripped portion lOb from the base end side leaving a predetermined gap from the base end surface of the main body 10. The base end of the rod 27 provided in more or less the axial center in the longitudinal direction of the main body 10 projects into the space 59 formed by the base end surface of the main body 10 and the conductive plate 32. A negative electrode active substance 62 is provided up to a position level with the base end surface of the rod 27 on the outer circumferential portion touching the rod 27, inside the space 59. The outer circumferential portion of the negative electrode active substance 62, and the base end surface of the rod 27 and the base end surface of the negative electrode active subs positive electrode active substance 61 and the negative electrode active substance 62 is effected by the separator 63 and the wall delimiting the battery chamber 39a of the main body 10, the conductive plate 32 plays the role of an outer housing, and the rod 27 plays the role of an end rod in the central portion. Also, the negative electrode active substance 62 is in electrical contact with the rod 27 while the positive electrode active substance 61 is in electrical contact with the conductive plate 32.

In the seventh mode of embodiment, a mixed powder of acetylene black, which is a conductor, and carbon fluoride is used as the positive electrode active substance, while metallic lithium is used as the negative electrode active substance.

The battery construction 40 of this ion toothbrush is the same as a simplified construction of the commercially available bar like battery 22 shown in Figure 10, which is to say a construction in which the outer circumferential terminal 22f constituting the outer housing of the bar-like battery 22 is constituted by the conductive plate 32, the central terminal shaft 22g is constituted by the rod 27, and the gasket 22d has been excluded. Consequently, the battery construction can be reduced in size compared with the case when a bar-like battery 22 is used and, as a result, the size (thickness) of the main body 10 can be reduced.

It should be noted that the battery construction 40 according to this seventh mode of embodiment may be provided in the position of the battery construction shown in Figure 4.

Preferred conditions which might be mentioned for the positive electrode active substance comprised in the batttery construction according to the present invention include that it exhibits a high electrode potential, has a large electrical capacity, is electrochemically active, is insoluble in the electrolytic liquid and is chemically stable; and substances apart from those described in the modes of embodiment discussed above include mercury oxide, silver oxide, copper oxide fluorine, graphite fluoride, copper chloride and nickel oxides. Further, negative electrode active substances which might be mentioned include magnesium and magnesium alloys as well as lithium and zinc.

Electrolytes which might be mentioned include brine, sodium hydroxide, potassium hydroxide, ammonium chloride, zinc chloride and zinc oxide.

The separator can be any porous separator which preserves a state of electrical insulation between the positive electrode substance and the negative electrode substance, has a large ion permeability and an appropriate mechanical strength: examples including nylon, polypropylene, polyethylene, cotton and asbestos paper.

Further, the battery construction of the ion toothbrush according to the present invention may be formed in a part other than the gripped portion lOb, for example the portion where the brush bristles 12 are implanted or elsewhere.

Again, the battery construction is not limited to the modes of embodiment discussed above provided that it is formed integrally with the main body, is configured so as to be watertight to the outside, and at least part of the external housing is constituted by the handle.

Yet again, in the ion toothbrush according to the present invention , the positive electrode active substance and the negative electrode active substance may be covered by a thin conductive film (such as a metal thin-film), and the portion of the main battery body which needs to be insulated may be covered by an insulating film. Doing this further simplifies the manufacture of the battery construction.

As described above, the ion toothbrush according to the present invention comprises a construction whereby at least part of the main battery body is defined by the handle, or in other words at least part of the external housing of the battery is constituted by the handle, and it allows the elimination of members other than fundamental constituents of the battery, for example gaskets, and as a result it allows the battery construction part to be reduced in size.

Consequently, the size of the handle can be reduced and it is possible to provide an easily grasped ion toothbrush.

Further, it is possible to achieve a potential difference of about 1.5 to 3 V which is required in an ion toothbrush to achieve satisfactory effects, for example, which is a potential difference about the same as from a commercial battery. Furthermore, since there is no need to use commercial batteries, the cost of the ion toothbrush can be reduced.

Claims

CLAIMS:

1. An ion toothbrush comprising: an insulating main body; brush bristles implanted in a front end of said main body; and a battery construction formed integrally with said main body; wherein one of the electrodes of said battery construction is configured so as to be able to connect with said brush bristles, and the other electrode is configured so as to be able to connect with the gripped portion of said main body.

2. An ion toothbrush according to Claim 1, wherein said battery construction is arranged in such a way that a positive electrode active substance, a negative electrode active substance and an electrolyte are accommodated in a battery chamber formed in said main body, and the wall of said main body delimiting said battery chamber constitutes part of an insulating.mechanism between said positive electrode active substance and said negative electrode active substance.

3. An ion toothbrush according to Claim 1, wherein said one electrode is the negative electrode and said other electrode is the positive electrode.

4. An ion toothbrush according to Claim 2, wherein said positive electrode active substance comprises an oxide.

5. An ion toothbrush according to Claim 1, wherein the electrolytic liquid contained in said battery construction is non-aqueous.

6. An ion toothbrush substantially as hereinbefore described with reference to any of Figures 1 and 2, Figure 3, Figure 4, Figure 5, Figure 6, Figure 7 or Figure 8 of the accompanying drawings.