FIELD OF INVENTION:
[001] The present invention relates to the field of multilayer lacquering. The present invention in particular relates to a system and method for multiple layer Jacquering to give a flat finish and avoid the convex look.
5 DESCRIPTION OF THE RELATED ART:
[002] Watches have been increasing the ornamental effect as an important factor these days, and various watches abundant in ornamental effect have been developed. As for the ornamental effect of watches, a dial plate has a larger weight. For example, the metal surface of dial plate is engraved or patterned in a 10 great variety.
Reference may be made to the following:
[003] Patent No US4250219 relates to protective coating, especially for aircraft bodies and the like, has one or more primer layers and one or more top coat layers, as well as an intermediate layer which is easily dissolved. The intermediate 15 layer protects the primer when the top coat is removed for a new paint job.
[004] Patent No US5507928 relates to a process for the production of a multi¬layer lacquer coating by dry-on-wet application of a powder coating composition onto a substantially uncrosslinked, previously electrophoretically deposited lacquer layer, followed by the joint baking of these lacquer layers.
20 [005] Publication No DE4215070 relates to a method for preparing multilayer coatings (finishes) in which at least one thermocurable clear coat is applied to a substrate provided with a pigmented base coat and is fully cured at elevated temperature, after which at least one further clear coat based on radiation-curable coating compositions is applied and fully cured under the action of actinic
25 radiation.

[006] Patent No US9050626 relates to the invention, it is thus clear that it is no longer necessary to selectively deposit the decorations. The prior structuring operation allows the adhesion and/or non adhesion areas to be precisely selected in order to simplify the step of depositing the decoration(s). In accordance with 5 other advantageous features of the invention: Step b) is for locally reducing the adherence of the surface of the body so that, in step c), the deposited layer does not adhere to the altered portions; The reduction in adherence is obtained by forming bosses alternately with hollows, the height and width of the hollows being respectively comprised between 50 and 200 |om, and 5 and 10 |im, and the
10 width of the bosses between 0.1 and 3 jam; Step b) is for locally increasing the adherence of the surface of the body so that, in step c), the deposited layer adheres to the altered portions; The increased adherence is obtained by forming bosses alternately with hollows, the height and the width of the hollows being respectively comprised between 2 and 10 (im and 5 and 20 jim, and the width of
15 the bosses between 5 and 20 [im.
[007] Publication No JPS5914039 relates to a display combined touch panel adapted to be used as input means of an electrode t touch panel for driving a liquid crystal. In a conventional touch-sensitive touch panel using a liquid crystal, it is necessary to prepare an electrode for a touch panel separately from an electrode 20 for driving a liquid crystal. For this reason, in addition to the layer to be encapsulated in the liquid crystal, a touch panel layer for providing an electrode for the touch panel is necessary, and as a result, the thickness of the display combined touch panel itself is increased, there were five drawbacks.
[008] Publication No GB1356534 relates to dial e.g. for a watch comprises a 25 metallic base-plate 1 having a thin plate of nacreous or iridescent shell 2 bonded thereto by adhesive 4, the rear face of the shell being substantially covered by an opaque layer 3. The adhesive 4 may be applied in patches and the layer 3 prevents any irregularity in the adhesive being visible from the front of the shell 2. The layer 3 may be formed of paint or lacquer or by electroless plating; one or several

colours may be used. Aligned holes lb, 2a are provided for hand shafts, and feet la for fixing to a watch plate.
[009] Publication No GB1427674 relates to timepiece a part of which has been coated with a material by a process comprising establishing a plasma glow 5 discharge between the part and the material to evaporate the coating material which is deposited on the part. The coating material may be at least one of Fe, Co, Ni, W, Mo, Ti, Cr, Th, Ag, Zr, Ta, Au, Pd, Cu and Al, an alloy or intermetallic compound or a carbide, nitride, oxide, boride or silicate or an Ag alloy containing at least one of Sb, In, Cd, Ni, Co, Cr, Au, Rh, Ru, Pd, Pt, Os, Sn, Re, W or Mo.
10 [010] Patent No US5734628 relates to three-dimensional watch dial plate structure abundant in ornamental effect is provided fully utilizing the characteristics of an electro-optical display device such as a liquid crystal device or an electrochromic device.
[011] Patent No US4250219 relates to protective coating, especially for aircraft 15 bodies and the like, has one or more primer layers and one or more top coat layers, as well as an intermediate layer which is easily dissolved. The intermediate layer protects the primer when the top coat is removed for a new paint job.
[012] Patent No US3863439 relates to watch dial has an outer surface consisting of metal crystals large enough to be seen by the naked eye. Such crystals are 20 formed by annealing of the metal and may have been treated by etching, coloring, dyeing, coating, oxidation or sulphuration.
[013] Publication No GB 1356534 relates to dial e.g. for a watch comprises a metallic base-plate 1 having a thin plate of nacreous or iridescent shell 2 bonded thereto by adhesive 4, the rear face of the shell being substantially covered by an 25 opaque layer 3. The adhesive 4 may be applied in patches and the layer 3 prevents any irregularity in the adhesive being visible from the front of the shell 2. The layer 3 may be formed of paint or lacquer or by electroless plating; one or several

colours may be used. Aligned holes lb, 2a are provided for hand shafts, and feet 1 a for fixing to a watch plate.
[014] Publication No GB1427674 relates to timepiece a part of which has been coated with a material by a process comprising establishing a plasma glow 5 discharge between the part and the material to evaporate the coating material which is deposited on the part. The coating material may be at least one of Fe, Co, Ni, W, Mo, Ti, Cr, Th, Ag, Zr, Ta, Au, Pd, Cu and Al, an alloy or intermetallic compound or a carbide, nitride, oxide, boride or silicate or an Ag alloy containing at least one of Sb, In, Cd, Ni, Co, Cr, Au, Rh, Ru, Pd, Pt, Os, Sn, Re, W or Mo.
10 [015] Publication No DE4215070 relates to a method for preparing multilayer coatings (finishes) in which at least one thermocurable clear coat is applied to a substrate provided with a pigmented base coat and is fully cured at elevated temperature, after which at least one further clear coat based on radiation-curable coating compositions is applied and fully cured under the action of actinic
15 radiation. Finishes of particularly good visual quality are obtained.
[016] Patent No US3932357 relates to polyurethane coating lacquer composition for substrates such as wood, metal, concrete, leather and plastics includes conventional solvents and I. The reaction product of 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl-isocyanate with branched chain polyesters having terminal
20 hydroxyl groups based on mixtures of aliphatic and aromatic dicarboxylic acids, said polyester and said isocyanate being reacted without a catalyst at 10 deg -35 deg C. in such quantities that there are two isocyanate groups per -OH group, and 15-85 mol percent of the dicarboxylic acids are aliphatic and the remainder aromatic acids; and II. An aldime having the formula wherein each r is the same
25 or different alkyl having 1 to 8, preferably 1 to 4 carbon atoms.
[017| Thus there are a lot of methods available for the finishing of dial but all the existing method provides convex look. Hence there exists a need of a method for flat finish in watch dial.

[018] In order to overcome above listed prior art, the present invention aims to provide a system and method for multiple layer lacquering to give a flat finish and avoid the convex look.
OBJECTS OF THE INVENTION:
5 [019] The principal object of the present invention is to provide a system and method for multiple layer lacquering to give a flat finish.
[020] Another object of the present invention is to provide a system and method for multiple layer lacquering to avoid the convex look.
SUMMARY OF THE INVENTION:
10 [021] The present invention relates to a system and method for multiple layer lacquering to give a flat finish and avoid the convex look. After the base of the dial is ready for enamel lacquering dials are placed on a special fixture which is an iron flat grill that keeps the dial in a flat position. The machine has a conveyor unit. The Fixture is kept on that unit. When the machine is on conveyor moves
15 and fixture is in the centre. A lacquering gun filled with the enamel lacquer moves in horizontal & vertical direction i.e. left to right & vice versa. The speed of lacquer is controlled automatically and the lacquering gun can be tilted at different angles. This process gives sharp edges as per customer requirement on any of the openings on the dial base.
20 [022] In the present invention, enamel lacquers are used with thinner in ratio of 5:1 respectively. In multilayer lacquering process we leave the dials for natural drying at lacquering room temp after first layer and after final multilayer. This natural dry time is given to allow the thinner to evaporate from the lacquer base and product should only be left with the enamel lacquer. The product after enamel
25 lacquer left behind is to be then baked at different temp setting for different time periods to the allow the lacquer on base to be baked up to the core with no left

oven thinner in it. Thorough baking is needed as if thinner is left inside the lacquer layer this can result in dent or pitting on base after a period of time.
BREIF DESCRIPTION OF THE DRAWINGS:
[023] It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments.
[024] Figure 1 shows a system and method for multiple layer lacquering to give a flat finish and avoid the convex look according to the present invention.
[025] Figure 2 shows a process flow according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION:
[026] The present invention provides a system and method for multiple layer lacquering to give a flat finish and avoid the convex look. After the base of the dial is ready for enamel lacquering dials are placed on a special fixture (a washer grills provided to allow the dials to lacquered without sticking to the grill base) which is an iron flat grill that keeps the dial in a flat position.
[027| The fixture comprises stainless steel washer grill 1, brazed stainless steel (SS) washer 2 and washer thickness 3 which allows dial to be in lifted position from grill base. The fixture allows the dial not to top stick with grill base while lacquering. If instead of special fixture normal grill was being used then dials will stick with grill base leaving irregular outer edges of the dials which is not acceptable by the customer or operational need.
[028] Multi layer enamel lacquering is done to cover the drilled holes in order to give the flat surface after lapping which is not possible with normal lacquering method. Multi layer enamel lacquering is done so that after lapping of the dials,

holes must not be seen with any shadow effect (zone around the index holes) around the index edges.
[029| The machine has a conveyor unit. The Fixture is kept on that unit. When the machine is on conveyor moves and fixture is in the centre. A lacquering gun filled 5 with the enamel lacquer moves in horizontal & vertical direction i.e. left to right & vice versa. The speed of lacquer is controlled automatically by control unit which controls and monitors the speed of the lacquering gun and the lacquering gun can be tilted at different angles. This process gives sharp edges as per customer requirement on any of the openings on the dial base. The step include 10 following steps (figure 2):
[030J Step 1- base formation with matt lacquer or color lacquer along with enameled lacquer.
[031] Step 2 inspection of base to avoid any lacquer dust particles or foreign components on the base.
15 [032] Step 3 putting all the dials on special fixture in order to place the product at a certain height from the fixture base.
[033] Step 4 multilayer process including setting machine parameters like gun orifice opening, operating pressure of lacquering line, scrubber exhaust air pressure from the lacquering booth, relative humidity of lacquering booth and dust 20 free environment.
[034] Step 5- first 5 layer to be set in machine parameters along with other parameters like orifice opening of the lacquering gun required operating pressure, height from the working fixture etc.
[035] Step 6 -after first layer allow the layer to dry.

[036| Step 7- then for another 5 layers set the machine parameters with changed lacquering gun's orifice opening & movement of the lacquering gun in another direction.
[037| Step 8- now allow the final layer to dry for another 12 to 14hrs at the same 5 temperature at what we did the enamel lacquering.
[0381 Then goes to step baking.
[039] In the present invention, enamel lacquers are used with thinner in ratio of 5:1 respectively. In multilayer lacquering process the dials are left for natural drying at lacquering room temp after first layer and after final multilayer. This
10 natural dry time is given to allow the thinner to evaporate from the lacquer base and product should only be left with the enamel lacquer. The product after enamel lacquer left behind is to be then baked at different temp setting for different time periods to the allow the lacquer on base to be baked up to the core with no left oven thinner in it. Thorough baking is needed as if thinner is left inside the
15 lacquer layer this can result in dent or pitting on base after a period of time.
[040| Numerous modifications and adaptations of the system of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the true spirit and scope of this invention. ° l^UL,L- Llmuea

WE CLAIM:
1. A system and method for multiple layer lacquering comprising a special fixture comprising stainless steel washer grill 1, brazed stainless steel (SS) washer 2 and washer thickness 3 which allows dial to be in lifted position from grill base wherein to place the dial on an iron flat grill in a flat position, the machine has a conveyor unit, the fixture is kept on that unit and when the machine is on conveyor moves and fixture is in the centre, a lacquering gun filled with the enamel lacquer moves in horizontal & vertical direction and the speed of lacquer is controlled automatically and the lacquering gun can be tilted at different angles.
2. The system and method for multiple layer lacquering, as claimed in claim 1, wherein the method includes following steps:

a) base formation with matt lacquer or color lacquer along with enameled lacquer
b) inspection of base to avoid any lacquer dust particles or foreign components on the base
c) putting all the dials on special fixture in order to place the product at a certain height from the fixture base
d) multilayer process including setting machine parameters like gun orifice opening, operating pressure of lacquering line, scrubber exhaust air pressure from the lacquering booth, relative humidity of lacquering booth and dust free environment
e) first 5 layer to be set in machine parameters along with other parameters like orifice opening of the lacquering gun required operating pressure, height from the working fixture etc.
f) after first layer allow the layer to dry.

g) then for another 5 layers set the machine parameters with changed lacquering gun's orifice opening & movement of the lacquering gun in another direction
h) now allow the final layer to dry for another 12 to 14hrs at the same temperature at what we did the enamel lacquering
i) then goes to step baking
The system and method for multiple layer lacquering, as claimed in claim 1, wherein the enamel lacquers are used with thinner in ratio of 5:1 respectively.
The system and method for multiple layer lacquering, as claimed in claim 1, wherein the multi layer enamel lacquering is done to cover the drilled holes in order to give the flat surface after lapping which is not possible with normal lacquering method so that after lapping of the dials, holes must not be seen with any shadow effect (zone around the index holes) around the index edges.