Patent application title: NAIL FILE
Anne Jensen (Copenhagen, DK)
IPC8 Class: AA45D2904FI
Class name: Toilet nail device (e.g., manicuring implement) abrader, file or buffer
Publication date: 2009-01-29
Patent application number: 20090025744
A nail file, including a file sheet and a handle, wherein at least the
file sheet is made of biscuit porcelain, the file sheet containing an
1. A nail file, comprising; a file sheet and a handle, wherein at least
the file sheet is made of biscuit porcelain, the file sheet containing an
2. The nail file as recited in claim 1, characterized in that both the file sheet and the handle are made of biscuit porcelain.
3. The nail file as recited in claim 1, characterized in that the abrasive agent is burnt biscuit porcelain, quartz, or minerals in ground form.
4. The nail file as recited in claim 3, characterized in that the abrasive agent is burnt biscuit porcelain.
5. The nail file as recited in claim 1, characterized in that only one side of the file sheet is made abrasive.
6. The nail file as recited in claim 1, characterized in that one end of the file is fashioned non-abrasively, as a handle.
7. The nail file as recited in claim 1, characterized in that one end of the file is fashioned non-abrasively, as a tip.
8. The nail file as recited in claim 1, characterized in that one side of the file sheet is fashioned so as to have different degrees of abrasiveness in different segments.
9. The nail file as recited in claim 1, characterized in that the two sides of the file sheet are fashioned so as to have different degrees of abrasiveness.
The present invention relates to a nail file whose file sheet is made of biscuit porcelain, the file sheet containing an abrasive surface.
It is already known to manufacture nail files for filing toenails from metal, glass, ceramic, or plastics. A nail file made of porcelain is also already known.
DE 10 2005 013 387 A1 discloses a nail file comprising a handle and a file sheet, in which at least the file sheet is made of feldspar porcelain. The file sheet has an abrasive surface that is situated on the file sheet as a coating. The file sheet is made of a pure feldspar porcelain compound, the coating for producing an abrasive surface not being applied until a subsequent work step, namely by glazing. The glazing or coating contains a mixture of kaolin, courts, and feldspar, and has emery as an abrasive agent.
In order to manufacture such a file from feldspar porcelain, first the raw mixture of feldspar porcelain is cast in a mold, and subsequently the cast and dried porcelain blank is immersed in the glazing slurry, i.e., the glazing in liquid form, the slurry containing the abrasive agent. The file blanks coated in this way are then dried and are subsequently burned at approximately 1400° C., yielding the nail file.
According to a another variant of the method, it is provided that the feldspar porcelain blanks are first subjected to a first burning at approximately 1400° C., and are then immersed in the glazing slurry containing the abrasive agent, and are then burned a second time at approximately 1400° C.
DE 10 2005 013 387 A1 also already proposes that the abrasive agent be incorporated immediately in the porcelain compound in order to create an abrasive surface on the file as a result of the properties of the material. In the description of said patent application, it is indicated that such a procedure would have the disadvantage that the abrasive agent embedded in this way in the porcelain compound would disturb the structure of the feldspar porcelain in such a way that a file made in this way would have an increased brittle fracture characteristic.
On the basis of the porcelain file known from the prior art, the present invention is based on the object of creating a nail file of the same general type that has sufficient hardness for its intended application and has a satisfactory brittle fracture characteristic, but has a simple construction and is less expensive to manufacture.
This object is achieved by a nail file that, in contrast to the nail file known from the prior art, is made not of feldspar porcelain but rather of biscuit porcelain.
Accordingly, the nail file according to the present invention, comprising a file sheet and a file handle, is characterized in that at least the file sheet is made of biscuit porcelain, the file sheet containing an abrasive agent.
Porcelain contains, as essential components, clay, feldspar, and quartz. Clay is made of aluminum silicates containing water. In the relevant prior art, the terms kaolin or porcelain clay are also used to refer to this material.
In order to manufacture the porcelain, the named initial materials are ground and are mixed with water to form a taste which is subsequently molded. The porcelain is produced from this paste by sintering or burning.
Typical formulas for manufacturing porcelain comprise a mixture of the named initial materials in ratios of approximately 50:25:25 to 30:30:40 percent by weight). However, mix ratios differing significantly from these may also be used. This is due not least to the fact that the initial materials are naturally occurring minerals whose composition may vary greatly from region to region.
The terms "feldspar porcelain" and "biscuit porcelain," their methods of manufacture, and the initial materials required to manufacture them are known to those skilled in the art from their use in the porcelain industry.
Feldspar porcelain is a generic term for porcelain coated with a glazing. Here, a glazing is applied to a porcelain blank. The use of a glazing causes the particles contained in the porcelain compound to bond to one another during the sintering or burning required to manufacture the porcelain; this yields a porcelain having a hard surface. The glazing usually gives the porcelain a smooth surface.
Biscuit porcelain is a generic term for porcelain that is not glazed, i.e., in which the use of a glazing is omitted. In general, it is not as hard as feldspar porcelain. In addition, its surface is usually rougher than that of feldspar porcelain.
Preferably, a light-colored clay is used as initial material for manufacturing the raw porcelain compound for the manufacture of the nail file according to the present invention, so that after manufacture the nail file has a light color that is attractive to the user.
The porcelain compound used for manufacture may contain aggregates. Aggregates are for example quartz, preferably present in the form of sand, preferably as very fine-grained sand or ground native rocks. Other aggregates that are standardly found in porcelain manufacturing include for example additional minerals related to clay or kaolin.
The addition of ground pumice can also increase the porosity of the burned product, also contributing to the roughness and abrasive effect of the surface of the file.
In a first working step, the components of the biscuit porcelain provided for the manufacture of the nail file are mixed with water in such a way that a soft, pliable paste, the raw porcelain compound, results.
The paste is subsequently cast in a mold that forms the nail file in the desired size and shape. The mold is preferably a very hard, fire-resistant clay mold.
Portions that protrude or that extend past the mold are removed, for example by scraping.
The abrasive surface of the nail file according to the present invention is created through the incorporation of abrasive agents into the porcelain compound used for the manufacturing, or through the application of abrasive agents onto the surface of file blanks that have not yet been burned.
Preferably, an abrasive agent is carefully distributed on the surface of the molded nail file blank, and is incorporated into the raw mixture of the blank through the application of pressure.
The abrasive agents are selected from the group containing: ground burnt biscuit porcelain, ground pumice stone, ground quartz (also in the form of sand), diamond powder, emery.
Minerals, preferably in ground form, can also be used to produce the abrasive surface. Minerals are naturally occurring solid materials having a uniform chemical composition and a structure that is uniform on the microscopic level. Examples include oxides, hydroxides, carbonates, sulfides, sulfates, and phosphates of metals.
Ground, burnt biscuit porcelain, ground quartz, or ground minerals are particularly preferable for use as abrasive agents.
Quite particularly preferred as an abrasive agent is ground, burnt biscuit porcelain.
The grain or degree of coarseness of the abrasive surface, which determines the filing effect, can be set via the degree of grinding. According to the standard used in the abrasives industry, the grain of the abrasive surface of the nail file is in general 180 to 800 microgrit. The microscopically determined distance between the grains present on the surface of the file is in general 0 to 25 μm.
After the application of the abrasive agent, the mold containing the file blank is sintered or burnt at a temperature of 1400° C. to 2300° C. The burning temperature is preferably from 1600° C. to 2100° C., in particular from 1700° C. to 2000° C.
The burning or sintering process preferably lasts from one to three days. In general, good results are achieved after a sintering or burning duration of 40 to 70 hours, preferably 40 to 50 hours.
In this way, the nail file is given a hardness and a brittle fracture characteristic that are well-suited to its intended use.
During the sintering or burning, a loss of material of up to 15% may occur due to the escaping volatile components.
After the termination of the burning process, the mold containing the nail file is slowly cooled to room temperature. Unwanted particles adhering to the file can be rinsed off using water, preferably a jet of water, after removing the file from the mold if warranted. This simultaneously cleans and polishes the file.
The abrasive agent embedded in or on the surface of the biscuit porcelain produces an abrasive surface without disturbing the composition of the biscuit porcelain, so that the brittle fracture characteristic required for use is not adversely affected. The file then has strength sufficient for its intended use. This is surprising in view of the disadvantages known from the prior art.
In contrast to the nail file known from the prior art made of feldspar porcelain, which has to be glazed in order to apply the abrasive coating, the nail file of the same general type according to the present invention, made of biscuit porcelain, does not contain a glazing. Because the additional work steps involved in producing the glazing slurry, applying the glazing, and a possible second burning are omitted, the nail file made of biscuit porcelain, having otherwise similar manufacturing steps, is simpler and more economical to manufacture with respect to production costs than is the known file made of feldspar porcelain.
The shape of the nail file may be freely selected via the shape of the clay mold.
The nail file is preferably fashioned in one piece, i.e., both the file sheet and the file handle are made of biscuit porcelain.
For example, it is possible to shape the mold in such a way that the nail file runs to a pointed tip at one end and is rounded at the other end.
It may also be manufactured so that it is rounded at both ends.
In a specific embodiment of the nail file, only one side of the file sheet is made abrasive.
In another specific embodiment of the nail file, one side of the file sheet is made abrasive and the other side is made porous.
The abrasive agent can be applied on one side of the surface of the file blank provided as the file sheet in such a way that regions of this surface do not contain abrasive agent.
For example, end regions of the nail file may be produced in such a way that they do not contain any abrasive agent. Such parts can then be fashioned as the handle or also as the tip of the file.
Thus, in another specific embodiment the surface of the nail file has a non-abrasive region that acts as the handle.
In another specific embodiment, the surface of the nail file has a non-abrasive region fashioned as the tip. The tip is then used to clean fingernails or toenails.
In another specific embodiment, it is also conceivable during the manufacture of the nail file to apply differently abrasive agents in different regions on the surface of the file blank. In this way, the finished file can be given a surface that has different grains in different regions or segments. In another specific embodiment, it is also conceivable first to place abrasive agent into the mold, and subsequently to add the porcelain raw mixture and then to apply abrasive agent to the exposed surface in the manner described above. After the manufacture of the nail file, both sides of the file sheet then contain abrasive agent.
Because the nail file according to the present invention is made of porcelain, it can advantageously be cleaned for example in boiling water, because it is inert relative thereto. This simultaneously permits sterilization without damaging the file. The file can then advantageously be used for example in hospitals, and for different patients.
Examples of specific embodiments of the nail file are shown in FIGS. 1 to 4.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a top view of a nail file according to the present invention having a tip and a round end, having an abrasive surface a.
FIG. 2 shows the nail file according to the present invention of FIG. 1 in a side view.
FIG. 3 shows a nail file according to the present invention having rounded ends in a top view, having an abrasive surface a.
FIG. 4 shows the nail file according to the present invention of FIG. 3 in a side view.
Patent applications in class Abrader, file or buffer
Patent applications in all subclasses Abrader, file or buffer