File, particularly nail file Field of the invention The invention involves a file, particularly for nails, manufactured from glass.
Description of the prior art Nail files, which are among the principal components of the various sets of cosmetic equipment, are at the present time manufactured from various metals or their alloys, from paper or fabric with a rough finish, as the case may be. Since files destined for such purposes are often used in an environment with high humidity, for example during personal hygiene in the bathroom, it happens in some cases that they corrode or the material from which the file is made becomes moist resulting, on the one hand, in a deterioration in appearance and, on the other, a dulling of the cutting edges of the file from the effects of corrosion and humidity and, thereby, a basic loss of effectiveness. If non-corrosive materials are used in the manufacture of files, which is generally the case, then the disadvantage is the high price. The disadvantage of metal files in which the cutting edges are formed by mechanical means is also the limited"smoothness"of the file, and the fact that by mechanical means it is possible to produce only a limited degree of roughness of the abrasive surface. Likewise, it is simply not possible to produce a series of files with finely graded roughness. It is convenient, in the use of a file, that the side edges be functional, that is rough. Because metal files are flat and too thin, it is not practical to use their side edges to trim the nails.
Summary of the invention The above disadvantages are eliminated in the file according to the invention presented here, the basis of which lies in the fact that it is made from glass roughened on at least part of its surface, with a roughness varying from 10 to 100 pm.
The advantage of such a file is its absolute resistance to the environment in which it is used. It is significant too that, given its non-corrosive properties, the abrasive surfaces can be kept clean by rinsing in water.
It is important to note here the wide range of surface roughness that can be attained, varying from the smoothest finish with a roughness of 10 ut to a roughness of around 100 pm.
The glass body of the file has an oblong board shape and has a point at one end at least. The advantage of such a shape for the glass body of the file is the ease of manipulation in use and, thanks to the point, its practical value for hand hygiene is increased.
Another advantageous solution to be noted is the fact that the glass body of the file is roughened along one whole side at least, having a V-shaped point at the end. The advantages of such a file are apparent both during use of the file and during its manufacture, when roughening of the whole surface is carried out without the need, for instance, to mask part of the surface during the roughening process by use of acid engraving for example. The point is formed in a V shape, its symmetrical shape facilitating manipulation during use of the file in either the left or the right hand.
A further advantageous feature is the fact that body of the file is roughened along one whole side at least and is ground to a sharp finish on at least one edge. The longitudinal edge formed on one side of the body of the file further increases the functional possibilities of the nail file.
It is possible to form the body of the file so that both edges are bevelled, while the bevelled edge at the end is at an oblique angle to the side edge, so that together they form a point. This variation further increases the wide range of uses for the file.
Another advantageous arrangement for the shape of the body of the file, consisting in the fact that the surface of at least one of the edges and of one end of the body of the file is also roughened, further contributes to increasing its usefulness.
To further improve performance, the edges of the body of the file are rounded. These variations in the shape of the glass file further extend its usefulness for special cases of hand hygiene.
From the point of view of production technology, it is an advantage if the body of the file can be formed from flat or pressed glass.
All the various shapes of the file can have a glass body formed from hardened glass. The advantages of such a treated glass body are its increased stability and particularly increased safety in the event of breakage of the whole of the glass body by dropping etc. The hardening of the glass-bodied file gives it properties which are well-known in such treated glass.
Brief description of the drawings The invention can be better described by means of the drawings, of which Figure 1 represents an "axonometric overview of the glass body of the file. Figure 2 presents a cross section of the glass body of the file with roughening on one surface. Figure 3 also shows a cross section of the glass body of the file with roughening on one side and rounded edges. Similarly, Figure 4 presents a cross section of the glass body of the file, both of whose edges are bevelled.
Description of the preferred embodiments The file according to Figure 1 is formed from a glass body 1, shown here in oblong board shape, with a roughening 4 on the surface 2. The roughening 4 is produced by a wide variety of techniques, the choice depending upon the degree of roughness. To produce the smoothest finish, for example around 10 pun, a chemical process can be used, such as acid engraving with a hydrogen fluoride solution.
Greater roughness, of around 100 pm for instance, can be produced mechanically, by sanding for example. Figure 2 shows a cross section of the glass body 1 of the file illustrated in Figure 1, with a roughened finish 4 along the whole of one surface 2.
Figures 3 and 4 illustrate further possible variants on the glass body 1 of the oblong board-shaped file.
A cross section is shown of the glass body 1 of the file, with roughening 4 of one surface finish 2, the glass body 1 of the file having rounded edges 3, while the cross section in Figure 4 presents the glass body 1 of the file with edges 3 bevelled to a sharp finish, the glass body 1 of the file having a rough finish 4 on both surfaces 2.
Industrial use of the invention The glass-bodied file has been described from the point of view of its use as a nail file. This example of use, however, in no way excludes further possible uses in other fields, particularly given the wide range of roughness which can be achieved in the glass-bodied file. A file produced according to this invention with a low degree of roughness, that is to say the finest, can be used in polishing surfaces, for example, while the coarsest can be used for grinding.