Formation of a three-dimensional object on a dial

1 . A deposition method for the formation of an object for a watch; the object including a perimeter, at least one first surface and/or a volume; the deposition method comprising at least one step of:

supplying at least one support comprising at least one receiving surface;

depositing an adhesion layer on the at least one receiving surface, said adhesion layer being formed of one or more layers made of at least one material selected from among Au, Cu, Ag, In, Pt, Pd, Ni, Ti, Ta, Cr, Th or an alloy of these materials, so as to render said at least one receiving surface electrically conducting;

delimiting an outline on the deposited adhesion layer; the outline corresponding to the perimeter, to the at least one first surface and/or to the volume of the object;

forming a cavity along the outline by depositing, on the adhesion layer, a plurality of polymer layers, such that a portion of the adhesion layer equivalent to the perimeter, to the at least one first surface and/or to the volume of the object is opposite and is not covered by polymer layers;

filling the cavity by depositing on the opposite portion of the adhesion layer at least one finishing layer comprising at least one material selected from Au, Cu, Ag, In, Pt, Pd, Ni, Ti, Ta, Cr, Th or an alloy of these materials; and

carrying out a surface treatment on the plurality of polymer layers and the deposited adhesion layer so as to expose the at least one receiving surface of the support,

wherein the deposition of the plurality of polymer layers is made by additive manufacturing,

wherein said cavity is formed along a median of said object and/or said outline is formed along the median of said object,

wherein a first portion of the cavity has a first perimeter length defined along a first plane perpendicular to a depositing direction of the plurality of polymer layers, and a second portion of the same cavity has a second perimeter length defined along a second plane perpendicular to a depositing direction of the plurality of polymer layers, the first and second planes are different from each other and the first perimeter length and the second perimeter length being a different length,

wherein the median is oriented perpendicular to the at least one receiving surface,

wherein said object comprises an undercut along the median in said plurality of polymer layers, and the undercut is included in the outline delimited on the deposited adhesion layer,

wherein after carrying out the surface treatment on the plurality of polymer layers and the deposited adhesion layer, a perimeter length of the adhesion layer is different from each of the first portion and the second portion,

wherein the object includes at least one second surface,

wherein each of the at least one first surface and the at least one second surface is defined by a curved outer perimeter,

wherein the at least one second surface that is more curved than said at least one first surface, and

wherein a perimeter length of at least one of the at least one first surface and the at least one second surface changes along the median of the object.

2 . The deposition method according to claim 1 , wherein said at least one finish layer comprises at least one material selected from among Au, Pt, Ag, Cr, Pd or an alloy of these materials.

3 . The deposition method according to claim 1 , wherein said surface treatment is carried out by pickling and/or stripping.

4 . The deposition method according to claim 1 , wherein said support is made of ceramic.

5 . The deposition method according to claim 1 , wherein said deposition of said adhesion layer is carried out in contact with said at least one receiving surface.