Abstract:
A hair brush of antistatic plastic material comprises an apertured base plate in the form of a grid having bristles integrally moulded therewith. The base plate is convexly curved in the finished brush with the bristles on the convex side and the grid construction imparts to the brush sufficient resilience to allow the relatively stiff integrally moulded bristles to execute a comfortable brushing action.

Description:
DESCRIPTION 
     The present invention concerns an anti-static hair brush comprising at least one flexible base plate made of a rigid plastic. 
     To make brushes with a sufficiently flexible base plate to be fixed on various frames or fittings so as to present a fan-shaped bristle structure, one has, until now, been obliged to attach these bristles to the base plate, for instance by welding the bristles on the flat plate, whereupon the assembly of the plate was effected on the appropriate shaped mounting so that the bristles made, for instance, of nylon and welded to the base plate made, for instance, of rubber diverge from each other so as to obtain an external fan shape or hedge-hog type structure which is favourable for brushing. According to another method for manufacturing brushes, an integrally moulded flat member was obtained, comprising a single base plate and bristles. In fact, in this latter case, it was necessary to use a sufficiently rigid plastic to endow the bristles with the resistance and elasticity necessary for good brushing, giving rise to a base plate which did not have the deformation characteristics suitable to all the mountings. Moreover, it was not possible to use any elastomer material since the hairs catch on the bristles. 
     The aim of the invention is to obviate these manufacturing drawbacks of the previous method by providing a new type of hair brush having a sufficiently flexible base plate to be obtained by moulding together with the brushing bristles. 
     The present invention therefore provides an antistatic hair brush comprising a handle and at least one brush element carried thereby, the said brush element comprising a flexible base plate made of an antistatic plastic material and provided with holes to define a grid forming a supporting structure for the bristles which are integrally moulded together with the base plate and are disposed perpendicular to the said plate. 
     In a preferred embodiment of the base plate, this grid forming the supporting structure is constituted by a multiplicity of diverging radial ribs, most of which are supported on, on the one hand, a central oval-shaped element and, on the other hand, the outer oval-shaped peripheral edge of the base plate, these ribs being arranged in an intersecting relationship with further oval-shaped elements situated in the same plane as the ribs regularly interspaced from each other and disposed substantially concentrically in relation to each other and in relation to the central oval-shaped element and to the outer peripheral edge of the base plate; each bristle is situated in a zone defined between the intersections of two adjacent radial ribs with a said oval-shaped element; each bristle is situated equidistant from the intersections of two adjacent ribs with a said oval-shaped supporting element; the grid forming the base plate is constituted by ribs intersecting at right angles so as to define zones between two adjacent ribs over which the brush bristles are distributed in a regular manner; each bristle is situated equidistant between the intersections of two adjacent ribs with a third rib; the base plate is made of polyamide 12, or of `Rilsan` (a Registered Trade Mark for nylon 11), or of Rilsan grafted to a block copolymer of polyether and polyamide; the plastic material forming the base plate and the bristles contains at least one antistatic carbon constituent. As an antistatic carbon constituent, there may advantageously be used those described in French Patent Publication No. 2,460,198. 
     In a first embodiment of the brush according to the invention, the brush handle and its base plate may be obtained integrally by moulding. 
     In accordance with a second embodiment, the base plate constitutes a component which is distinct from the supporting handle, the said base plate being moulded flat. 
     According to a third embodiment of the brush of the invention, the supporting handle is provided with an opening having on its inner side surface a peripheral groove having a dovetail cross section to receive the edge of the base plate by catch engagement, the said base plate assuming a convex shape on the side on which the bristles are arranged. 
     According to a fourth embodiment of the brush according to the invention, the brush handle comprises a recess whose floor comprises a plurality of oblong or circular through holes, the recess having on its inner side surface a groove having a dovetail cross section to receive the base plate by catch engagement, whereby the base plate assumes a convex shape on the side whereon the bristles are distributed. 
     A first variant of the base plate has a rectangular shape and is rolled up cylindrically and welded on its two opposite edges to form a bristled cylindrical base element. 
     In a first embodiment of the brush using this first variant of the base plate, the bristled cylindrical base element is fitted on a cylindrical support. 
     In a second embodiment using this first variant of the base plate, the bristled cylindrical base element is fixed to its associated supporting handle by being held between the brush hand grip and a cap, the hand grip and the cap forming two elements of the same supporting handle and being each disposed near one of the ends of the bristled cylindrical base element. 
     In a third embodiment of the brush using this first variant of the base plate, the brush handle is extended axially by a rod having at its free end a catch engagement stud intended to cooperate with a corresponding recess provided in the cap. 
     A second variant of the base plate is formed by a rectangular base plate provided on two of its opposite edges with a fastening structure formed by a strip flexible in its connecting zone with the rest of the base plate, the said strip having a longitudinal rib on its free edge. 
     In a first embodiment of the brush using this second variant of the base plate, the brush handle is extended axially by a contoured element with a substantially crescent-shaped cross-section comprising a longitudinal axial groove to receive the correspondingly shaped lower end of the axial flange of a slidable holding element of a substantially T-shaped cross section, the top part of the T constituting a cap which surmounts the contoured element, the slidable holding element and the contoured element defining between them recesses to hold the longitudinal ribs of the base plate. 
     In a second embodiment of the brush using this second variant of the base plate, the brush handle is extended axially by a contoured element with a crescent-shaped cross-section having a central axially extending flange whose upper edge is formed as a rib; said flange being disposed between two grooves of said contoured element of the handle, said contoured elements of the hanndle accommodating a slidable holding component having axially a shape constituted by two longitudinal side flanges thickened on their free edges to define a shape corresponding to the flange and to the two grooves of the contoured element of the handle so as to be capable of slide engagement thereon, said slidable holding element comprising two side flanges which, by cooperating with the contoured element of the handle, hold the base plate by its longitudinal ribs. 
     The slidable holding element has, at its end, near the brush handle, a projection adapted to engage in a recess in the handle. 
     In these various embodiments proceeding from the above defined three variants of the base plate, the brush of the invention has a certain number of improved characteristics, especially as regards resistance to wear and to chemical action, imparted to it by the rigid plastics materials used for its manufacture, these characteristics being superior to natural or synthetic elastomers which are normally used. By reason of the perforated structure of its base plate, this brush has excellent elasticity, is more easily cleaned and can be very rapidly dried after being washed. Even if a blow dryer is used, the static charges set up by the blowing dissipate from their points of generation. 
    
    
     In order that the invention may more readily be understood, a number of embodiments, shown in the accompanying drawings will now be described, merely by way of illustrative but not restrictive examples. In these drawings: 
     FIG. 1 is a top view of a first form of the base plate for a brush according to the invention; 
     FIG. 2 is a view in perspective of a first embodiment of the brush according to the invention; 
     FIG. 3 is an axial longitudinal cross-sectional view of the brush of FIG. 2; 
     FIG. 4 is an axial longitudinal cross-sectional view of a second embodiment of the brush according to the invention, formed as two components; 
     FIG. 5 is a perspective view of a third embodiment of the brush according to the invention; 
     FIG. 6 is a perspective view of a fourth embodiment of the brush according to the invention; 
     FIG. 7 is a view in a transverse cross-section of the embodiment of FIG. 6; 
     FIG. 8 is a top view of a variant of the base plate according to the invention; 
     FIG. 9 is a perspective view of a first embodiment of the brush according to the invention using the plate variant of FIG. 8; 
     FIG. 10 is a perspective view of a second embodiment of the brush according to the invention, using the base plate of FIG. 8; 
     FIG. 11 is a perspective view of a third embodiment of the brush according to the invention using the base plate variant of FIG. 8; 
     FIG. 12 is a second variant of the embodiment of the base plate for a brush according to the invention; 
     FIG. 13 is a perspective view of a first embodiment of the brush acccording to the invention using the base plate of FIG. 12; 
     FIG. 14 is a perspective view of the brush obtained by assembling the elements of FIGS. 12 and 13; 
     FIG. 15 is a transverse cross-sectional view of the brush of FIG. 14; 
     FIG. 16 is a perspective view of a second embodiment of the brush according to the invention, using the base plate of FIG. 12; 
     FIG. 17 is a perspective view of a brush according to the invention, obtained by assembling the brush elements shown in FIGS. 12 and 16; and 
     FIG. 18 is a transverse cross-section of the brush of FIG. 17. 
    
    
     Referring now to the drawings, there will be seen an oval-shaped perforated base plate 1 for a brush according to the invention. This plate is formed by a plurality of ribs supported by and disposed between, on the one hand a central oval-shaped element 3 and, on the other hand, an edge 4 of the oval-shaped base plate 1. Between this central element 3 and edge 4, there are disposed, concentrically in the same plane as ribs 2 and in an intersecting relationship therewith, a plurality of oval-shaped elements 5 regularly interspaced from each other and disposed concentrically between the edge 4 and the central element 3. Some of the ribs 6, 7, 8, 9, 10, which are supported on edge 4 are shorter than the rest and do not reach the central element 3, this design having been conceived because of the oval-shaped design of base plate 1. 
     On one of the sides of this base plate 1, and perpendicular thereto, there are arranged a multiplicity of bristles 11 integrally moulded together with the base plate 1. These bristles 11 are advantageously situated in the zone defined by the intersection of two adjacent radial ribs with one of the oval-shaped elements, each bristle being situated equidistantly between the said intersections. 
     This net-like perforated structure endows the base plate 1 with such flexibility that it can be obtained jointly with a mounting or support 12 and a handle 13 by integral moulding. 
     In the embodiment of FIG. 4, made in two parts, the support or mounting zone of the brush handle 14 has an opening with, over the periphery thereof, a catch engagement groove 14a having a dovetail cross section. This groove is dimensioned so that after the base plate 1 has been introduced into it by catch engagement, the base plate assumes a convex shape on the side on which the bristles 11 are distributed. 
     In the embodiment of FIG. 5, the support zone 15a of handle 15 is provided with a plurality of oblong holes 15b; catch-engagement means (not shown) are also provided on the lower side of the support zone 15a for fixing the base plate 1 therein. This mode of embodiment is more particularly appropriate for use with a device for dispensing hair treatment products or with a blow dryer for the hair. 
     In the embodiment of FIG. 6, the support or mounting zone 16a of the handle 16, intended to support the base plate 1, is provided with a multiplicity of through holes 16b having the same function as the oblong holes 15b of the embodiment of FIG. 5. The lower side of the support zone 16a has a cut out around the periphery of which is a groove 17 having a dovetail cross section dimensioned so that, by catch engagement, the base plate 1 is capable of assuming a convex shape on its side carrying the bristles 11 so that the bristles may diverge from each other, thus presenting a distribution in space which is suitable for brushing. 
     In FIG. 8, there has been shown a top view of a variant of the base plate 1. This base plate 18 is constituted by ribs 19 intersecting each other at right angles and having, between the intersections of two adjacent ribs with another rib, bristles 20 which are perpendicular to the plane of the plate. 
     This base plate 18 advantageously has a rectangular shape so that it may be rolled up and welded by two of its edges onto a cylindrical fitting 24 so as to form a cylindrical support element 21. On this cylindrical support element 21, the bristles 20 are radial and diverge from each other thereby facilitating brushing. This cylindrical support element 21 may have a brush handle 22 connected to and fixed at one of its ends while the other end is provided with a cap 23 (see FIG. 9). 
     In the embodiment of FIG. 10, the cylindrical support element 21 is fitted on a fitting 24 having at one of its ends a cap 24a whilst its other hand is tapped so as to accommodate the threaded end fitting 25a of an elongate round handle 25. 
     In the embodiment of FIG. 11, handle 26 is also provided with a threaded end fitting 26a and extends axially from this end fitting 26a via a rod 27 provided at its free end with a conical snap-fitting stud 27a slit axially and intended to catch engage in a recess 28a of corresponding shape in a cap 28. This arrangement is more particularly suited to hollow support elements of a flexible type; for greater flexibility, the support element may also be dispensed with, the base plate 18 being maintained in a cylindrical roll without any other support except that of the ends. 
     In the variant of FIG. 12, the base plate 29 has a net-like structure of the same type as the plate of FIG. 8 as regards the disposition of ribs 30 and of the bristles 31. Moreover, this base plate is extended on its two opposite edges by side strips 32a, 32b which are connected to the base plate proper by way of a bending zone 33a, 33b and which have their free end edges 34a, 34b in the shape of thickened ribs. 
     This type of plate 29 is more especially intended to be mounted on brush handles formed as two components, as shown more precisely in FIGS. 13 and 16. In the embodiment of the brush shown in FIG. 13, the handle 34 is extended axially by a support element 35 in the form of a contoured rod having a substantially crescent-shaped cross section. This contoured rod has, on its concave shape, an axially extending groove 35a shaped to hold by slide insertion, the lower longitudinal rib 36a of the central flange 36 of a slidable holding component 37 having a substantially T-shaped cross-section. The two side strips 37a, 37b come by sliding to a position covering the concave face of the support element 35 so as to define two side housings on either side of the central flange 36 wherein there are held, with a given clearance, the end ribs 34a, 34b of side strips 32a, 32b of the base plate 29 of FIG. 12. 
     When the brush is assembled, the side strips 32a, 32b are bent through the required angle so that they can be held on the concave face of support element 35 whereupon the rib 36a of holding element 37 is introduced by sliding inside the groove 35a until the end cap 37c covers the free end of the support element 35. To endow the base plate 29, shaped into a brush element for a half-round brush, with transverse clearance for imparting flexibility to it, the cap 37c of the slidable holding element 37 should not abut against the said base plate 29. 
     In the embodiment of FIG. 17, the brush handle is also formed by two parts capable of being assembled by slide insertion. The first part is constituted by the handle 38 proper axially extended by a contoured support element 39 whose cross-section is substantially crescent-shaped. This contoured support element 39 is provided with an axially extending longitudinal flange on its concave side. This flange 40 has along its free edge a rib 40a. This rib 40a is intended to be slide-fitted in a longitudinal recess provided on the concave side of a contoured holding element 41 having a crescent-shaped cross-section. For this purpose, this concave side is provided with two substantially longitudinally extending flanges 41a, 41b defining therebetween a groove corresponding in shape to the rib 40a so that the rib 40a may be engaged therein by slide insertion. This holding element 41 is provided at one of its ends with a cap portion 41c and comprises along its side edges flanges 41e, 41f whose concave sides are provided with respective longitudinal ribs 41g, 41h. The holding element 41 comprises at its end opposite from cap 41c, a projection 41d engaging in a recess 38a of a corresponding shape in the handle 38. 
     When this embodiment is assembled, the base plate 29 is, by bending its side strips 32a, 32b, made to assume the required shape so that the corresponding side ribs 34a, 34b may be kept in contact with the edge regions of the concave side of support element 39, whereupon the holding element 41 is engaged so that its internal ribs 41g, 41h cooperate with the side edges of the support element 39 so as to hold the side ribs 34a, 34b of the base plate 29 with a given clearance within the recesses bounded by the slidable holding element 41 and the contoured support element 39. One thus obtains a so-called &#34;quarter round&#34; brush. On completion of the assembly operation, the engagement of the projection 41d provided on the slidable holding element 41 within the recess 38a of the handle 38 prevents these two elements from turning with respect to each other. 
     In these last two embodiments of the brush in accordance with the invention, the scope for bending deformation and transverse displacement of the retaining ribs of the base plate 29 allows the base plate a suppleness of movement which is reflected in a higher quality brushing action. 
     The carbon constituent of the plastic material to give it its antistatic properties may comprise carbon fibres or a powdered &#34;carbon gasification&#34; product of the type disclosed in said French Patent Publication No. 2,460,198. The preparation of such a carbon product, formed by incomplete combustion of heavy hydrocarbons to prepare a gaseous mixture containing carbon monoxide and hydrogen is described in U.S. Pat. No. 2,914,418, British Pat. Nos. 734,475 and 780,120, at page 227 of &#34;1967 Petrochemical Handbook&#34; (Published November 1967), and at pages 118-1122 of &#34;Industrial and Engineering Chemistry&#34;, Volume 8 No. 7. 
     It shall be duly understood that the embodiments described above are in no way restrictive and may give rise to any desirable modifications without thereby departing from the scope of the invention as defined by the following claims.