DESCRIPTION

Field of the invention

The present invention relates to the field of water sports and more particularly it relates to a method for implementing a surfboard or other board such as body board, wind surf board, stand-up paddle board, wake surf board, wake board, kite surf board, skinboard, soft- top board.

Moreover, the invention relates to a surfboard realized with such method.

Description of known art

As it is known, the implementation of the traditional surfboards very often takes place starting from a core made of light material, for example polystyrene or foam polyurethane, obtained by means of using moulds or by cutting, or made of cork, such as EP2422948A. The so- obtained raw core can be further modelled with cutting tools, for example for milling and shaping, so as to obtain a semi-finished product having the wished shape.

Once the core is modelled, it passes to a resin-coating step, wherein it is coated with glass fibre and resin. After resin hardening, a step of smoothing down and polishing the surface layer takes place, at first by means of abrasive tools capable or removing glass fibre roughness and excess resin, and then a flatting step takes place in order to obtain the wished finishing level. At last, sometimes a spray of thin protective transparent varnish is applied. Some types of board, then, have directional fins at the tail.

The so-obtained boards result to be relatively light and at the same time robust enough to sustain the user's weight and they have the ideal surface finishing for sliding well on water.

However, a step of smoothing down and surface polishing the resin and the glass fibre has the drawback to produce gases and powders which, if inhaled, can cause health problems. As the powders are very thin, they produce micro-nanometric particulate, difficult to be removed by means of filters, causing environmental pollution.

Moreover, in order to reach a surface smoothing down having a satisfactory finishing, one has recoursed to excess in resin and glass fibre, with consequent high amounts of produced powders and high resin waste, with double negative effect on the production cost and higher environmental pollution.

In each case, the steps of resining and smoothing down the resin require many working hours. Some types of surfboard, for example as described in US3514798A, have a core made of material with honeycomb structure, providing at the same time robustness and more lightness. As far as the outer contour of the boards is concerned, apart from a traditional edge made of smoothed resin, there are also reinforced solutions. For example, in US20080287017A1 a surfboard example is shown with core made of foamy material, and the use of carbon fibre along the outer contour, in order to make the structure stiffer in case of impacts.

However, the above-described boards, even if they have the advantage of being light, thanks to the use of foamy materials or cores with honeycomb structure, result to be fragile, especially after exposure to the sun or due to accidental impacts which may happen during practicing the sport. In fact, it may happen that as time passes, after impacts or exposure to the sun, or to the heat of a car's interior in the summer periods or to the simple use, detachment phenomena, better known as "delamination", occur between the outer surface made of resin and the core. Other waste phenomena are mainly caused by the low elasticity of the layers of materials joined therebetween which, after repeated mechanical stresses, and impacts, first of all generate crushing until structural failures with consequent surface cracks and water infiltrations requiring immediate stopping and finishing interventions in order to avoid the board rupture.

WO1998042496A1 describes a method for producing surfboards providing the use of a mould, wherein a core coated with a fabric impregnated with resin is inserted, and a subsequent step for hardening under vacuum the material contained therein. Through such method, with a reduced number of working steps, a surfboard provided with good stability and stiffness is implemented.

In each case, by means of such method the step of the final smoothing down, and the consequent resin waste and production of powders, is not avoided. Moreover, such productive process, by using moulds with predetermined shape, allows to obtain only standardized and not customizable surfboards.

US9045201B1 shows a method for the production of surfboards implemented by alternating layers of cork with other materials different from cork, in order to obtain a multi-layer. An under vacuum curing of the manufactured product can be further provided. However, even if an optimum lightness has been reached, the lack of a core made of resilient material determines a limited robustness.

Summary of the invention

An object of the present invention is to provide a method for producing a surfboard which does not require excessive consumption of resin and which allows to reduce pollution caused by the step of surface finishing.

Another object of the present invention is to provide a method for implementing a surfboard requiring less working time with respect to the existing systems.

An additional object of the present invention is to provide a method for implementing a surfboard solving, at least partially, the drawbacks of the known methods.

A particular object of the present invention is to provide a method for producing a surfboard which is economically advantageous, and in particular which allows to obtain a final form so as to allow saving in amount of glass fibre and polymeric resin.

Still an object of the present invention is to provide a surfboard implemented with such method and having the above-mentioned advantages.

Still an object of the present invention is to provide a surfboard which is less sensitive and prone to surface rupture in case of impacts.

Still an object of the present invention is to provide such surfboard which reduces the delamination risk.

A further object of the present invention is to provide such surfboard which is robust and at the same time smooth and light.

A further object of the present invention is to provide such surfboard having a less stiff contour and surface than the existing boards and then creates less damage in case of contacts with people or things.

These and other objects are reached by a method for producing a surfboard comprising the following steps of:

- prearranging a semi-finished core having:

- an outer contour,

- a first and a second face opposite to each other defined by said outer contour; - prearranging at least one coating sheet configured to cover at least one among said first face and second face, at least except for said outer contour,

said at least one sheet having an edge;

- applying to said at least one face a resin layer and applying said at least one coating sheet on said resin layer, so that said edge of said at least one coating sheet does not cover said outer contour;

- applying resin on said edge and applying on said edge at least one edge cover element so that said edge is pressed between said face and said edge cover element;

- curing said resin so as to make said sheet, said face and said edge cover element integral to each other; and

- smoothing down said contour and said edge cover element.

In this way, after resin reticulation the sheet edge remains covered by the edge cover element, and then it does not expose outside by offering a delamination triggering. Moreover, the sheet does not require surface finishing and, as the resin remains below the sheet, a surface finishing removing resin, and thus producing environmental pollution, is not required. Moreover, the resin below the sheet is lower than the one which would be required in case of outer resining and then, as no excess resin has to be removed, there is a lower consumption in the same with savings in production costs.

Advantageously, between said first and/or said second face and said contour there is a tapered portion and said edge of said sheet is arranged above said tapered portion.

In this way, the sheet edge follows the tapered portion, by approaching to the axial plane of the board, and the edge cover element which is glued above the edge does not result to project too much from the board once this is finished.

In a possible embodiment, said edge cover element is a sheet made of cork even entirely covering the whole second face and said step for applying resin on said edge also provides applying resin on the whole second face and on said contour.

In this way, the board will require smoothing-down only in a limited area, that is on the overlaying area between the sheet edge and the edge cover element, in the form of sheet made of cork. In particular, the sheet made of cork forming the edge cover element allows to adapt to the whole contour of the board and to the second face without forming wrinkles. Even in this case between the first face and said contour there is a tapered portion and said edge of said sheet is arranged above said tapered portion. In this way, as in the above-described case, the sheet edge follows the tapered portion, by approaching to the axial plane of the board, and the edge cover element, in the form of a sheet made of cork, is glued above the edge and the circumference thereof does not result to project too much from the board once this is finished.

An alternative embodiment provides the steps of:

- prearranging a first and a second coating sheet of said first face and second face, configured to cover said first face and second face except for said contour, said first and second sheet having a respective edge;

- applying to said first face a resin layer and applying said first coating sheet on said resin layer;

- applying to said second face a resin layer and applying said second coating sheet on said resin layer;

- applying resin on said first and second edge and applying on said first and second edge a first and second edge cover element so that said first and second edge are pressed between said first and second face and said first and second edge cover element, respectively;

- curing said resin so as to make said sheet, said faces and said edge cover elements integral to each other; and

- smoothing down said contour and said edge cover elements.

In this way, the first face and second face are covered by two respective sheets which do not require a surface finishing. Only the edge cover elements and a portion of the contour require a smoothing-down procedure.

In particular, the or each sheet is made of metal, for example a plate with reduced thickness of 0.2mm to 0.6mm, preferably around 0.4mm. This allows to have a good surface finishing analogous to the smooth glass fibre, without requiring any smoothing-down procedure. Moreover, it allows a greatly improved shock resistance with respect to the smooth glass fibre. In fact, the sheet integral with the semi-finished product after resin curing allows a high resistance to typical impacts of a board.

Preferably the or each sheet is made of aluminium plate. This allows a high lightness and malleability of the sheet in the step of applying to the face of the semi-finished product and the subsequent curing. Alternatively, the sheet can be a foil made of plastic material. For example, it can be implemented in a foil made of transparent plastic material, with polymers allowing to produce flexible plates, however having high surface resistance.

As additional alternative the sheet can be a foil made of wood or cork. In such case, a step for the waterproofing impregnation of said sheet can be provided.

Advantageously, the outer contour is obtained by the steps of:

- implementing one outer face on the semi-finished product;

- applying on the contour face of at least one contour strip made of shock resistant material, in order to form the outer contour.

In this way, the contour strip, extending peripherally around the whole board, and the edge cover element, which is parallel to the contour strip, can be joined and overlapped, in order to form one single contour of the board, after the smoothing down procedure.

In a possible embodiment, the coating contour strip of said outer contour is obtained by gluing peripherally at least a layer of said shock resistant material, for example cork. Said strip of shock resistant material can be even a multiple-layer strip. In case of multiple- layer strip, each layer can be glued to the subsequent one or to the contour face by means of a gluing agent, for example polyurethane glue.

In a possible embodiment, the edge cover element of both sheets is one single strip made of flexible material entirely covering the board contour. This solution, for example implementable with a foil made of cork which is fold like a U on the board contour with the side margins covering the sheet edges, allows to implement quickly the edge cover element of both sheets and even the shock resistance side strip.

In another possible embodiment variant, the edge cover element of both sheets is formed by two strips made of flexible material converging one onto the other one at the board contour. Even this solution, for example implementable with two strips in foil made of cork, allows to implement quickly both the edge cover element of both sheets and the shock resistance side strip. Each strip has a margin covering the edge of the respective sheet and the other margin converging and overlapping the margin of the other strip. In a step of smoothing down after the glue or resin solidification, the margins are smoothed down to form a smooth and rounded contour of the board. In still another possible embodiment, said contour strip defines a first and a second boundary abutment, and said edge of said first and second sheet are arranged on said first and second face within said abutment. This solution allows to make the sheet edge to further disappear and to make the edge cover element, after drying and smoothing down procedure, one single piece with the contour strip, by forming one single smooth and rounded contour of the board.

Advantageously, said edge cover element is made of cork. In this way, should the strip implementing the outer contour be made of cork, a continuity material is obtained between said outer contour and said edge cover element.

Advantageously, between said or each sheet and said or each face a respective layer of fabric is provided. This solution makes the board very resistant to rupture.

In particular, applying on said or each face of a layer of fabric soaked with resin is provided, thereto the procedure for applying said or each coating sheet on said layer of fabric soaked with resin follows.

In this way, the presence of the tissue soaked with resin gives the board additional stiffness, since the coating sheet upon adhering to the board is stressed at a traction state without sliding on the tissue, and this membrane tension reduces the drawing in case of impacts, actually by increasing the yield stress of the resulting structure. In particular the use of tissue made of glass fibre, carbon, kevlar, plant fibres, synthetic fibres is provided. Advantageously, the coating sheet is a sheet made of pre-cut aluminium. In such case, an optimum surface finishing and wished roughness of the aluminium is obtained, without additional metal smoothing and working.

In a first preferred solution, both faces have the coating sheet made of aluminium. This solution allows to have the two faces of the board with ideal surface finishing without any type of work for finishing the surface thereof, except possible painting.

In a second preferred solution, one face has the coating layer made of aluminium and the other face has the coating sheet made of cork. In this case, the surface made of cork is used as resting surface for the feet, giving greater pleasantness to the touch. The face made of cork does not require any surface finishing working by material removal, but simply a waterproofing impregnation with a paint of known type which, once dried, becomes smooth without additional working. Advantageously, said curing step is obtained by insertion in a vacuum bag, and a vacuum is applied until said resin is cured. In particular, the board with the or each sheet, the or each edge cover element, and the possible contour strip fixed to the semi-finished core by means of glue or resin, are wound in a plastic film, which is sealed by inserting between the film margins at least a tube for sucking air. All air inside the film is sucked until a predetermined degree of vacuum, which is kept for some hours, for example 4-8 hours. The film adheres strongly to the board, which is pressed by the outer atmospherical pressure for the whole drying time. The absence of air inside the bag and the pressure from outside determines an optimum curing of all above-mentioned portions.

In a possible embodiment of the invention, at the end of the step of applying vacuum, applying paint is provided along the first and the second edge cover and along the outer contour. In case of one cover face made of cork, it can provide applying paint, too. In this way both the first and second edge cover and the cover face made of cork result to be protected and not permeable to fluids.

Advantageously, in a possible embodiment of the invention the insertion of at least a reinforcement element within the core of the surfboard is provided, so as to obtain a higher resistance to the loads.

Such reinforcing element can be applied to the surface of the semi-finished core or be inside thereof. For example, on the core surface at least a lath made of carbon or other structural material can be applied.

In case of inner reinforcement element, it can be housed in a groove made in the semifinished core or inside the core itself.

Brief description of the drawings

Additional features and/or advantages of the present invention will result clearer with the following description of an embodiment thereof, made by way of example and not for limitative purposes, with reference to the enclosed drawings wherein:

figure 1 shows schematically a plan view of a board obtained according to the production method described by the invention;

figure 2 shows, in a section view, a starting semi-finished product to obtain the board of figure 1; figure 3 shows, in a section view, the implementation of one outer face and tapered portions on the half-finished product of figure 2;

figure 4 shows a view in partial section of a working step of a first embodiment of the method according to the invention;

figure 4A shows the partial view of figure 4 in a subsequent working step after resin and glue hardening and after the smoothing-down of the edge cover element;

figures 5-8 show in a partial section view, embodiment variants of the invention described in figure 4;

figure 9A shows an additional variant of the invention which provides applying on the contour face of the semi-finished core at least a strip of shock resistant material forming a recess with respect to the semi-finished product;

figure 9B shows, in a section view, a step of applying resin on the two faces of the semi-finished product of figure 5;

figure 9C shows, in a section view, a step of applying one coating sheet on the two faces of the semi-finished product of figure 9A and 9B;

figure 9D shows, in a section view, a step of applying a first and second edge cover element to the product shown in figures 5-7

figure 10 shows schematically a step of hardening and reticulating by insertion in the vacuum bag and applying vacuum of the semi-finished product;

- figure 11 shows the step of smoothing down the edge cover element and the strip implementing the outer contour;

figure 12 shows, in a section view, a step of final finishing of the board contour. Description of some preferred embodiments

Figure 1 shows a plan view of a surfboard 1 obtained according to the method described by the invention. Obviously, the method described hereinafter for several embodiments, apart from the surfboards further extends to other boards, such as those for body board, wind surfboard, stand-up paddle board, wake surf board, wake board, kite surf board, skinboard, soft-top board, which are not represented in order to provide a simple description.

In particular, the surfboard 1 comprises a central core, not visible in figure 1, an outer contour 25, at least one coating sheet 30 defining one of the two faces of the surfboard. The core of the surfboard 1 is obtained starting form a flat semi-finished product 20 made of foam polymeric material, as shown in figure 2, comprising an outer contour 25, a first face 21 and a second face 22. In particular, the starting flat semi -finished product 20 can be any material selected from polystyrene, for example EPS or XPS, EVA, foam polyurethane, or other foamed and not foamed materials, such as for example honeycomb profiles, moulded and coupled shells, provided with robustness and lightness features.

Figure 3 shows the step for implementing the contour face 29, by removing the material existing along the outer contour 25 and the production of a first 23 and second 24 tapered portion, obtained for example by means of a flatting procedure, or by moulding.

Figure 4 describes, according to an enlargement in section, a general embodiment implemented by the invention. In particular applying a resin layer 40 on the first face21 of the semi-finished product 20 and applying one coating sheet 30 on the resin layer 40 are provided, so that the edge 30' does not cover the outer contour 25. Moreover, in order to allow applying one edge cover element 50 resin 40 is applied on the edge 30' of the coating sheet 30 and on the first flattening 23 and along the contour face 29. In this way, the edge 30' of the sheet 30 is pressed between the face 21 and the edge cover element 50. Moreover, the sheet 30 does not require surface finishing and as the resin 40 remains below the sheet 30 a surface finishing, removing resin 40 and then producing environmental pollution, is not required. Moreover, the resin 40 below the sheet 30 is lower than the one which would be necessary in case of outer resining and then, as excess resin 40 has not to be removed, there is a smaller consumption of the same with savings in production costs.

As it can be seen in figure 4A, in a subsequent working step after resin hardening, the procedure for smoothing down the edge cover element follows, by creating continuity between the sheet 30 and the smoothed edge cover element 50.

Figure 5 shows an enlargement in section of a possible embodiment variant of the invention wherein applying a resin layer 40 on the first face 21 of the semi -finished product 20 and applying one coating sheet 30 on the resin layer 40 are provided. In particular, the coating sheet 30 is applied so that the edge 30' does not cover the outer contour 25. Moreover, to allow applying one edge cover element 50 implemented by a foil made of cork, for example having a thickness between 2 and 6mm, i n particular having a thickness of 4mm, apt to cover wholly all second face, the resin 40 is applied on the edge 30' of the coating sheet 30 and on the tapered portion 23, on the contour face 29 and on the whole second face 22. In this way, the edge 30' of the sheet 30 is pressed between the face 21 and the edge cover element 50. In this way, the resin 40 remains below the sheet 30 and below the face 22 by making not necessary a surface finishing removing excess resin and producing environmental pollution.

By applying the edge cover element 50 in this way the double effect of obtaining an outer contour 25 and a covering layer for the face 22 is implemented.

In the embodiment of figure 5, as the edge cover element 50 is a foil made of cork, it provides protection in case of impacts and optimum floating properties, apart from allowing to adapt to the whole contour of the board and to the second face without forming wrinkles. The coating sheet 30 can be a pre-cut sheet of aluminium allowing to obtain an optimum surface finishing without additional metal smoothing or working. The outer margins of the edge cover element 50 cover the edge of the coating sheet 30, by implementing the present invention.

Figure 6 shows an enlargement in section of an additional embodiment variant of the invention wherein applying a resin layer 40 on the first face 21 of the semi -finished product 20 and applying one coating sheet 30 on the resin layer 40 are provided. Applying a resin layer 40 on the second face 22 of the semi-finished product 20 and applying one coating sheet 30 on the resin layer deposited on the second face 22 are also provided. In particular, the coating sheet 30 existing on both faces21, 22 is applied so that the edge 30' does not cover the outer contour 25. Moreover, applying resin 40 on the edge 30' of both sheets 30, on the first 23 and second 24 flattening portions and on the contour face 29 are provided to allow applying two edge cover elements 50. Particularly, the edge cover element 50 of both sheets 30 is formed by two strips made of flexible material converging one onto the other one in order to cover the board contour.

Even this solution, for example implementable with two strips of foil made of cork, allows to implement quickly both the edge cover element 50 of both sheets 30 and the shock-resistant side strip.

The presence of resin in this way allows to make the edge cover elements 50 integral to each other. Moreover, the first face 21 and the second face 22 are covered by two respective sheets 30 which do not require a surface finishing. The edge cover elements 50 and a portion of the contour, only, require a smoothing down procedure.

As in case of figure 5, the edge cover element 50 can be an element made of cork providing protection in case of impacts and optimum floating properties, apart from allowing to adapt to the whole board contour and to the second face without forming wrinkles.

The coating sheet 30 is a sheet made of pre-cut aluminium allowing to obtain an optimum surface finishing without additional metal smoothing-down or working procedures.

Moreover, the coating sheet 30 can be made of cork.

In a possible embodiment one coating sheet can be made of cork and the other one can be of aluminium.

In a subsequent phase of the production method, as described hereinafter in figure 11, by smoothing down the outer contour 25 the working of the edge cover element 50 and the board contour edge cover element 50 is implemented.

Figure 7 shows an enlargement in section of an additional embodiment variant of the invention wherein applying a resin layer 40 on the first face 21 of the semi -finished product 20 and applying one coating sheet 30 on the resin layer 40 are provided. Moreover, applying a resin layer 40 on the second face 22 of the semi-finished product 20 and applying one coating sheet 30 on the resin layer deposited on the second face 22 are provided. In particular, the coating sheet 30 existing on both faces 21, 22 is applied so that the edge 30' does not cover the outer contour 25. Furthermore, applying resin 40 on the edge 30' of both sheets 30, on the first 23 and second 24 flatting portions and on the contour face 29 are provided to allow applying one edge cover element 50. In particular, the edge cover element 50 of both sheets 30 is one single strip made of flexible material entirely covering the outer contour 25 of the board. This solution, for example implementable with a foil made of cork allows to implement quickly the edge cover element of both sheets 30 and even the shock resistance side strip.

The possible embodiments for the variant of figure 6 are valid also for the variant for figure 7, such as the fact of providing one sheet made of aluminium, or both of them made of aluminium, or one made of aluminium and one made of cork or both of them made of cork. Figure 8 shows an enlargement in section of an additional embodiment variant of the invention wherein applying a resin layer 40 on the first face 21 of the semi -finished product 20 and applying one coating sheet 30 on the resin layer 40 are provided. Applying a resin layer 40 on thesecond face 22 of the semi-finished product 20 and applying one coating sheet 30 on the resin layer deposited on the second face 22 are further provided. In particular, the coating sheet 30 existing on both faces 21, 22 is applied so that the edge 30' does not cover the outer contour 25.

By applying one contour strip 60 of shock resistant material on the contour face 29 of the semi-finished product 20 the formation of the outer contour 25 is obtained.

Moreover, applying resin 40 on the edge 30' of both sheets 30, on the first 23 and second 24 flatting portions and on the contour face 29 are provided to allow applying a first and a second edge cover element 50.

In this way, the contour strip 60 and the edge cover element 50 can be joined and overlapped, in order to form one single board contour, after the smoothing down procedure. As in case of figure 5, 6, 7 the edge cover element 50 can be an element made of cork providing protection in case of impacts and optimum floating properties. Even the contour strip 60 can be made of cork, allowing a material continuity the line of demarcation thereof practically is not visible by the user after the smoothing down procedure.

The possible embodiments for the variant of figures 6 and 7 are valid also for the variant of figure 8, such as the fact of providing one sheet 30 made of aluminium, or both sheets 30 made of aluminium, or one made of aluminium and one made of cork or both of them made of cork.

Figure 9A shows a variant of the invention which provides applying on the contour face 29 of the semi-finished product 29 at least one contour strip 60 of shock resistant material, by defining in this way a first abutment 27 and a second abutment 28 of the first 23 and second 24 flattening portion, respectively. The strip 60 can be obtained for example by applying, by means of glue, two layers of cork, or other shock resistant material.

In this way, as shown even in the embodiment of figure 8, the edge cover element 50 and the contour strip 60 can be joined and overlapped (see figure 9D), in order to form one single contour 25 of the board, after the smoothing-down step.

In case several strips of shock resistant material 60 are used, they are joined therebetween and applied along the contour face 29 by means of a gluing agent, such as for example a polyurethane glue. Moreover, the shock resistant material preferably is cork, since it has optimum floating properties, resistance to the impacts and it is much less harmful as far as the particulate aspect is concerned, but the use of other materials, such as for example rubber, neoprene, EVA, shock resistant polystyrene, wood, silicone rubber, and so on, is not excluded.

Figure 9B shows, in a section view, a step for applying a resin layer 40 on the first face 21 and on the second face 22 and on the respective flattening portions 23, 24 of the semifinished product 20. In particular, the used resin is a type of resin which can be selected between epoxy resin and polyester resin.

Figure 9C, shows, in a section view, a step for applying a first 30 coating sheet on the resin layer 40 deposited on the first face 21 of the semi -finished product 20 and an additional coating sheet 30 on the resin layer 40 deposited on the second face 22 of the semi-finished product20. In particular, the coating sheet 30 placed on the faces 21 and 22 is arranged to insert within the first 27 and the second boundary abutment 28, so that the edges 30' of the coating sheets 30 are within the first 23 and second 24 flattening portion, respectively.

Figure 9D describes, in a section view, on the left side, a step for applying a first and a second edge cover element 50. An additional step of applying resin 40 on the edge 30' of the coating sheets 30 of the respective faces 21, 22 allows to arrange the fastening of a first and a second edge cover element 50. In this way, the edge 30' of the coating sheet 30 results to be pressed between the first 21 and the second 22 face.

In particular, the edge cover strips 50 preferably are made of cork, but they can also be made of a different material from cork.

Should the edge cover strip 60 implementing the outer contour 25 be made of cork, and the edge cover strip 50 be made of cork too, a material continuity between the outer contour 25 and the edge cover strips 60 is obtained.

In particular, in a possible variant, designated only on the top right in figure 9D, the edge cover strip 50' can be made of impermeable mastic or silicone rubber.

Moreover, both faces 21, 22 can have a respective coating sheet 30 made of aluminium, or the coating layer can be made of aluminium for one face and of cork for the other one, or both of them made of cork.

The productive steps shown in figures 9A-9D obviously can be applied even to the cases of figures 4,5,6,7,8, by analogy. Figure 10 shows schematically the step for inserting the board 1, implemented in anyone of the variants of figures 4,5,6,7,8,9A-D, in a vacuum bag 70 with subsequent application of vacuum by using a compressor 95, thereto a suction tube 96 of air is connected, the suction mouth thereof 97 is inserted in the vacuum bag 70.

In particular, the vacuum bag 70 can be implemented starting from an extended foil, for example made of nylon, which is folded again onto the board 1 and which through a taping 71 in proximity is closed again to guarantee the tightness of the bag 70 until the reticulation of the resin 40.

After reticulation of resin 40 the edge 30' of the coating sheets 30 remains covered by the edge cover element 50, thus not offering the cutting edge of the sheet, nor the sheets offer delamination triggers.

Moreover, since the resin 40 remains below the coating sheet 30, a surface finishing, removing resin and thus producing environmental pollution, is not required. Moreover, since excess resin has not to be removed, also savings in the production costs are obtained. After the step of curing under vacuum, the sheet 30 made integral to the semi-finished product after curing the resin allows a high resistance to the impacts typical of a board. Figure 11 shows an example of a step of smoothing down the edge cover element 50 and the strip implementing the outer contour 25, by means of polishing machine 90, apt to remove roughness and irregularities.

Figure 12 shows, in a section view, a step of final finishing the contour of the board 1, in an embodiment similar to those of figure 8 or of figure 9D.

Through the smoothing down step roughnesses are removed and contour continuity between the edge cover element 50 and the contour strip 60 of the board 1 is obtained. As far as the resin 40 is concerned, it can be resin suitable to apply glass fibre below the sheet 30, or polyurethane glue or other resin suitable to make the sheet 30 integral to the semifinished product 20, or to make integral the edge cover element 50 above the edge of the sheet 30, or to make the strip 60 integral to the edge cover element 50.

The polyurethane glue can be suitable to fill up the gaps between the edge cover element 50 and the semi -finished product 20 in the areas adjacent to the tapered portion 23 or 24, of the above- shown embodiments, if applicable. The above description of embodiments and specific examples of the invention is able to show the invention from the concept point of view so that other people, by using the known art, could modify and/or adapt in several applications such specific embodiments without additional research and within the inventive concept and then it is to be meant that other adaptation and modification could be considered as equivalent of the specific embodiments and the examples. The means and materials to implement the several described functions could have various nature, however not leaving for this reason the scope of the invention. It is to be meant that the used expressions and terms have a purely descriptive, and for this reason not limiting, purpose.