HK40008896B - Method for setting a stone - Google Patents

Description

Method for setting stone

Technical Field

The present invention relates to a method for assembling a stone on a base, said stone being cut so as to have a table, a crown, a girdle and a pavilion. The invention also relates to a method for setting the stone and its base in an element of a watch or piece of jewellery, the base being produced by said assembly method.

Background Art

Methods for setting precious, semi-precious, or artificial stones using claws, beads, or guides are known. Traditionally, natural stone setting, which involves using claws to fit the stone into a bezel, typically requires a dimensional accuracy of approximately 5/100 when the stone is cut. Consequently, this type of setting is unsuitable for serially produced, low-cost stone settings, which utilize stones cut with a higher accuracy of approximately 1/100, such as synthetic diamonds, zircons, and rubies.

Summary of the Invention

The object of the present invention is to overcome this drawback by proposing a method of setting stone that makes it possible to disregard the inevitable dimensional variations found when using natural stones such as diamonds.

To this end, the present invention firstly relates to a method for assembling a stone on a base, said stone being cut so as to have a table, a crown, a girdle and a pavilion, said method comprising the following steps:

a) providing a substrate comprising a hot melt adhesive layer;

b) positioning the stone on the hot melt adhesive layer of the substrate;

c) heating the hot melt adhesive layer;

d) applying pressure to the stone so that a portion of the crown or a portion of the pavilion of the stone is sunk into the sufficiently softened hot melt adhesive layer, leaving the remainder of the stone (i.e., the remainder of the crown, girdle, and pavilion, or the remainder of the pavilion, girdle, and crown, respectively) exposed;

e) positioning the inlay around the stone above the adhesive layer so as to form a circumferential free space between the inlay and the stone, at least at the level of the girdle, and at the level of the area of the crown adjacent to the girdle, and at the level of the area of the pavilion adjacent to the girdle;

f) depositing by galvanic growth a metal layer from a tessellation in said circumferential free space, at least at the level of the girdle and of the crown zone adjacent to the girdle and of the pavilion zone adjacent to the girdle, so as to sink said girdle in said metal layer, said metal layer and the tessellation forming said seat;

g) releasing the stone and its base from the substrate.

The method according to the invention uses a layer of hot-melt adhesive to position the stone so that it is not necessary to create a shell of sufficient size in advance to accommodate the stone. Thus, the method according to the invention allows dimensional variations of the stone to be disregarded.

The invention also relates to a method for setting a stone in a timepiece or jewellery element, comprising: fitting the stone and its base produced according to the method defined above to a bezel, which is then adhered to the timepiece or jewellery element, or fitting it directly to the timepiece or jewellery element.

The invention also relates to a timepiece or jewellery element comprising at least one stone assembled to its base, the base being produced according to the assembly method defined above.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages will become apparent from the following description, given for illustrative purposes and in a completely non-limiting manner, with reference to the accompanying drawings, in which:

1 to 5 are representations of the successive steps of the method for assembling a stone on a base according to the invention.

DETAILED DESCRIPTION

With reference to Figures 1 to 5, the present invention relates to a method for assembling a stone 1, cut so as to have a table 3, a crown 4, a girdle 5, and a pavilion 6, onto a base 2. This stone is preferably of natural origin, such as diamond or emerald, and its dimensions may vary depending on the stone. Obviously, the stone may be of any other type, whether natural or artificial, and the method according to the invention may be applied to such stones in an equally advantageous manner.

A first step a) of the method according to the invention for assembling a stone 1 on a base 2 consists in providing a substrate 8 comprising a layer 10 of hot-melt adhesive.

Preferably, the substrate 8 takes the form of a plate and is based on glass, ceramic, polymer, metal, silicon, quartz or any other suitable support having a flat surface. Advantageously, the substrate 8 is a glass plate.

The hot melt adhesive layer 10 is preferably a layer of adhesive of the hot melt type that is soluble in hot water or solvent, such as Crystalbond™ or Wafer-Mount™ adhesive or any other similar suitable mounting product.

The second step b) of the method according to the invention for assembling a stone 1 on a base 2 consists in positioning the stone 1 on the hot-melt adhesive layer 10 of the substrate 8. In an advantageous and particularly preferred manner, the stone 1 is positioned so that its top 3 is in contact with the hot-melt adhesive layer 10, as shown in FIG1 . In this manner, a plurality of stones can be positioned on the substrate. The positioning of the stones can correspond to a desired final shape, for example, a specific pattern.

The third step c) of the assembly method of the invention consists in heating the hot-melt adhesive layer 10 so as to soften it at least sufficiently to allow the stone 1 to sink into the hot-melt adhesive layer.

The fourth step d) of the assembly method of the invention consists in applying pressure to stone 1 so that, according to the variant shown here, only a portion of crown 4 of stone 1 can sink into the sufficiently softened layer of hot-melt adhesive 10, leaving the rest of crown 4, girdle 5 and pavilion 6 exposed, as shown in FIG2 . Advantageously, stone 1 is sunk until its table 3 comes into contact with substrate 8, thus ensuring that table 3 is flat.

Obviously, the order of steps b) and c) can be reversed. Advantageously, step b) can be performed after step c), in particular if the stone 1 is positioned so that its pavilion 6 is partially sunken in the sufficiently softened layer of hot-melt adhesive, leaving the rest of the stone exposed, so that the pavilion 6, the girdle 5 and the rest of the crown 4 remain exposed.

The depth of the hot-melt adhesive layer 10 is selected so that the crown 4 (or the pavilion 6, depending on the variant used) is practically fully immersed in the hot-melt adhesive layer 10 and in contact with the substrate 8, with only a portion of the crown 4 (or the pavilion 6) having a smaller thickness e (see FIG. 2 ) being exposed beneath the girdle 5. This portion would include the region 4 a of the crown 4 (or the region 6 a of the pavilion 6) adjacent to the girdle 5, as defined below.

The resulting assembly is cooled, causing the hot-melt adhesive layer 10 to solidify and retain the stone 1 on the substrate 8 without the need for a suitable housing to be formed in said substrate.

The use of the method of the invention then continues according to step e) by positioning a veneer 12 over the layer of hot-melt adhesive 10 (which has cooled and solidified), the veneer 12 being cut around the stone 1 so as to form a circumferential free space 16 between a portion 14 of the veneer 12 and said stone 1, at least at the level of the girdle 5, and at the level of the area 4 a of the crown 4 adjacent to the girdle 5, and at the level of the area 6 a of the pavilion 6 adjacent to the girdle 5.

The inlay 12 is made of an electrically conductive material, for example a metallic material selected from the group consisting of nickel, gold, silver, platinum, palladium, copper, brass and alloys thereof.

Step e) further comprises placing a lower insulating layer 18 between the hot melt adhesive layer 10 and the mosaic sheet 12 and placing an upper insulating layer 20 on the free surface of the mosaic sheet 12, as shown in FIG3 . The lower insulating layer 18 and the upper insulating layer 20 are cut around the stone material and sandwich the mosaic sheet 12. The insulating layer can take the form of a sheet of organic material (such as a polymer, resin, paint, etc.), or can be produced, for example, by PVD (physical vapor deposition), ALD (atomic layer deposition), CVD (chemical layer deposition), or other similar methods for depositing thin dielectric layers of SiO ₂ , Al ₂ O ₃ , TiO ₂ , AlN, Si ₃ N _4, etc.

Next, step f) of the method according to the invention consists in depositing a metal layer 22 by electro-growth from the portion 14 of the tesserae 12 in the circumferential free space 16, at least at the level of the girdle 5, and at the level of the region 4 a of the crown 4 adjacent to the girdle 5, and at the level of the region 6 a of the pavilion 6 adjacent to the girdle 5, so as to sink the girdle 5 in the metal layer 22, as shown in FIG4 . As a result of the sinking of its girdle 5 in the metal layer 22, the stone 1 is now integral with the tesserae 12, the metal layer 22, in the continuation of the tesserae 12, forming the base 2 in conjunction with the tesserae 12.

Preferably, the area 6 a of the pavilion 6 adjacent to the girdle 5 and the area 4 a of the crown 4 adjacent to the girdle 5 extend only directly on either side of the girdle 5, over a thickness less than the thickness e of the exposed portion of the crown, so as to form said metal layer 22 between the stone 1 and the inlay 12, substantially only around the girdle, that is to say only at the level of the girdle 5 and directly on either side of said girdle 5.

The metal layer 22 is preferably made of a material selected from the group consisting of nickel, gold, silver, platinum, rhodium, palladium, copper, and alloys thereof.

The electroforming conditions, in particular the composition of the plating bath, the geometry of the system, the voltage and the current density, are selected for each metal or alloy to be electrodeposited according to techniques well known in the art of electroforming (see, for example, Di Bari G.A., "Electroforming", Electroplating Engineering Handbook, 4th edition, edited by L.J. Durney, published by Van Nostrand Reinhold Co., Ltd., New York, USA, 1984).

The next step g) consists in releasing the stone 1 assembled on its base 2 from the substrate 8. This step g) is performed, for example, by dissolving the hot-melt adhesive layer 10 in an organic solvent. The insulating layer is removed by mechanical stripping, dissolution in an organic solvent, or chemical etching.

The result is a stone 1 assembled on its base 2 , as shown in FIG. 5 .

When a plurality of stones 1 have been positioned on the layer of hot-melt adhesive 10 in step b), the result is a base in the form of a plate comprising a plurality of stones 1 assembled onto said plate, the stones possibly forming a pattern.

Obviously, the dimensions of the base 2 are determined by the dimensions of the inlay 12. In particular, the thickness of the inlay 12 is preferably chosen so that the metal layer 22 is deposited only substantially at the level of the girdle 5 and at the level of the regions 4 a, 6 a, respectively, of the crown 4 and pavilion 6, extending only directly on either side of the girdle 5, as described above, thereby positioning the base 2 only substantially around the girdle 5, as shown in FIG5 . The base 2 extends slightly over the regions 4 a and 6 a, respectively, of the crown 4 and pavilion 6, adjacent to the girdle 5, but the majority of the crown 4 and pavilion 6 remain free.

The assembly method according to the invention allows dimensional variations of the stone 1 to be accommodated by allowing the stone to be assembled onto its base without the need to previously form a different housing of suitable dimensions for receiving the stone.

When released in this way, the stone 1 assembled on its base 2 can be used in the setting method according to the invention.

Said method for setting said stone in a timepiece or jewellery element comprises fitting the stone 1 and its base 2 produced according to the assembly method defined above onto a bezel, and then attaching the bezel to the timepiece or jewellery element.

In another variant, the stone 1 and its base 2 produced according to the assembly method described above are adapted directly on an element of a timepiece or piece of jewellery.

The base 2 , which supports the stone 1 on the bezel 38 or directly on an element of a timepiece or piece of jewelry, can be adapted by clamping, pressing, setting or other methods.

For example, the element of a timepiece or piece of jewelry may be a dial, a bezel, a rotating bezel, a case middle, lugs of a case, a crown, a hand, a pointer, a bracelet or other bracelet element, an element of a pendant, a ring, a necklace, etc., any lining or outer lining element, or any decorative element of a timepiece or piece of jewelry that can be set.

Claims (11)

1. A method for assembling a stone (1) onto a base (2), wherein the stone (1) is cut to have a countertop (3), a crown (4), a waist (5), and a pavilion (6), the method comprising the steps of: a) Provide a substrate (8) comprising a hot melt adhesive layer (10); b) Position the stone (1) on the hot melt adhesive layer (10) of the substrate (8); c) Heat the hot melt adhesive layer (10); d) Apply pressure to the stone (1) so that a portion of the crown (4) or a portion of the pavilion (6) of the stone (1) sinks into the sufficiently softened hot melt adhesive layer (10), while the remainder of the stone (1) is exposed; e) Position the inlay (12) around the stone (1) above the hot melt adhesive layer (10) to form a circumferential free space (16) between the inlay (12) and the stone (1), the circumferential free space (16) being at the level of the waist (5) and at the level of the second region (4a) of the crown (4) adjacent to the waist (5) and at the level of the first region (6a) of the pavilion (6) adjacent to the waist (5); f) A metal layer (22) is deposited from the patch (12) by electric current growth in the circumferential free space (16) at the level of the waist (5) and at the level of the second region (4a) of the crown (4) adjacent to the waist (5) and the first region (6a) of the pavilion (6) adjacent to the waist (5), so as to embed the waist (5) into the metal layer (22), the metal layer (22) and the patch (12) forming the base (2); g) Release the stone (1) and its base (2) from the substrate (8). 2. The method according to claim 1, wherein the first region (6a) of the pavilion (6) adjacent to the waist (5) and the second region (4a) of the crown (4) adjacent to the waist (5) extend directly only on either side of the waist (5), thereby forming the metal layer (22) between the stone (1) and the inlay (12) only around the waist (5). 3. The method according to claim 1, wherein the inlay (12) is made of a metallic material selected from the group consisting of nickel, gold, silver, platinum, palladium, copper and nickel alloys, gold alloys, silver alloys, platinum alloys, palladium alloys and copper alloys. 4. The method according to claim 1, wherein step e) further comprises placing a lower insulating layer (18) between the hot melt adhesive layer (10) and the insert (12) and placing an upper insulating layer (20) on the free surface of the insert (12). 5. The method according to claim 1, wherein the metal layer (22) deposited in step f) is made of a material selected from the group consisting of nickel, gold, silver, platinum, rhodium, palladium, copper and nickel alloys, gold alloys, silver alloys, platinum alloys, rhodium alloys, palladium alloys and copper alloys. 6. The method according to claim 1, wherein the substrate (8) is based on a material selected from the group consisting of glass, ceramics, metals, polymers and quartz. 7. The method according to claim 1, wherein the hot melt adhesive layer (10) is a soluble adhesive. 8. The method according to claim 1, characterized in that step g is performed by dissolving the hot melt adhesive layer (10). 9. The method according to claim 1, wherein a plurality of stones (1) are positioned on the hot melt adhesive layer (10) to form a base (2) in the form of a plate, the plate comprising a plurality of stones (1) assembled to the plate. 10. A method for setting a stone (1) into an element of a watch or a piece of jewelry, comprising: adapting the stone (1) and its base (2) produced by the method according to any one of claims 1 to 9 to a groove edge, and then adhering the groove edge to the element of the watch or the piece of jewelry, or adapting the stone (1) and its base (2) directly to the element of the watch or the piece of jewelry. 11. An element of a watch or a piece of jewelry, comprising at least one stone (1) assembled onto a base (2), said base (2) being produced by the method according to any one of claims 1 to 9.