EP0615773A1 - Snow-ski board and process for the fabrication - Google Patents

Abstract

Ski or other board for sliding over snow, including a protective and decorative top or shell. This top or shell consists of a multi-layer complex (7) which includes at least one opening (9) in the upper plastic layer (2). This upper layer (2) is transparent and it protects the decoration upstream (3) and downstream (4) of the central zone (6) which includes the underfoot zone (6). <IMAGE>

Description

The present invention relates to a ski, or other board for sliding on snow (monoski, snowboard, etc.), which comprises a protective or decorative top or shell made of plastic. It also relates to a method of manufacturing in the mold of such a ski or other board for sliding on snow.

• . Les skis dits "traditionnels" dont la structure comporte essentiellement, de bas en haut, une semelle de glissement bordée par des carres métalliques, une première couche de renfort constituée par exemple par un solide tissu en fibre de verre, un noyau, des chants latéraux qui bordent ce noyau et prennent appui sur les carres, une seconde couche de renfort qui recouvre le noyau, et finalement un dessus généralement plat, en matière plastique telle que par exemple de l'ABS (Acrylonitrile-Butadiène-Styrène).
• . Les "skis coques", plus modernes, pour lesquels les chants et le dessus précités sont remplacés par une seule coque en matière plastique dont la section est grossièrement celle d'un trapèze à angles arrondis.

The currently most widespread skis can be classified into two large families:

• . The so-called "traditional" skis, the structure of which essentially comprises, from bottom to top, a sliding sole bordered by metal edges, a first reinforcement layer constituted for example by a solid fiberglass fabric, a core, lateral edges which border this core and rest on the edges, a second layer of reinforcement which covers the core, and finally a generally flat top, of plastic material such as for example ABS (Acrylonitrile-Butadiene-Styrene).
• . The more modern "shell skis", for which the aforementioned edges and top are replaced by a single plastic shell, the section of which is roughly that of a trapezoid with rounded angles.

An extremely important element from the commercial point of view is the decoration which is worn on the visible external part of the ski, that is to say ultimately either on the layer of plastic material which constitutes the above-mentioned top of a traditional ski, or on the plastic shell of a ski shell. Various inscriptions and decorative patterns are pleasing to the eye, which make the ski attractive to customers regardless of its intrinsic and properly technical qualities.

In this regard, it should be noted that the plastic layer which forms the top of a traditional ski or the shell of a ski shell is often called "protective and decorative layer".

One of the objects of the present invention is to obtain a ski, or other board for gliding on snow, the external appearance of which is considerably improved from the aesthetic point of view, and on which effects are particularly striking from the visual point of view. can be obtained.

In the classic design, the patterns and inscriptions that are reported in various places of the upper part of the ski are protected by a thin layer of varnish. Such a design is not completely satisfactory, because the upper part of a ski undergoes, in particular upstream and downstream of the skate area, multiple mechanical attacks, either when the skier accidentally crosses his two skis, or when '' another skier goes on these same skis, or even walks on them when, for example, queuing in front of a ski lift. Under such conditions, the layer of varnish forms insufficient protection, and the screen printing itself can be quickly attacked and damaged.

This is why the Applicant Company now plans to cover the decorative layer of certain skis it manufactures, in particular shell skis, with a fairly thick layer of transparent protective plastic.

Document FR-A-2.660.251 of the Applicant Company may be cited as a state of the art relating to this kind of modern embodiment.

The choice of the constituent material of this transparent protective layer is particularly delicate, and depends very much on the manufacturing process which is used for the ski considered.

• Un premier procédé est le procédé dit "voie humide" qui schématiquement consiste :
  • . tout d'abord à empiler, dans le moule ouvert, les éléments constitutifs du ski : la semelle bordée par les carres éventuelles, une ou plusieurs couches de renfort inférieures, le noyau solide bordé par les chants éventuels, une ou plusieurs couches de renfort supérieures, et finalement le dessus plastique (plat ou en forme), l'ensemble de ces éléments étant préencollé par de la résine mélangée à son durcisseur mais non encore réticulée ou cuite ;
  • . puis à fermer le moule à l'aide de son couvercle sous une pression qui, étant par exemple de l'ordre d'une dizaine de bars, est suffisante pour assurer la mise en place correcte des éléments, et à monter l'ensemble en température pendant un temps prédéfini, cette température étant par exemple de l'ordre d'une centaine de degrés Celsius, de façon à provoquer la fluidisation puis le durcissement de la résine, et finalement la cuisson de l'ensemble ; après refroidissement de la structure ainsi obtenue, on ouvre le moule, on extrait le ski et on procède aux opérations de finition.
• Un second procédé, plus moderne, dit "injecté forme" qui consiste :
  • . a placer dans le moule ouvert la semelle, bordée par les carres éventuelles, et une ou plusieurs couches de renfort inférieures préencollées ou préassemblées ensemble et à la semelle, puis la coque plastique préassemblée à une ou plusieurs couches supérieures de renfort, en arquant cette coque pour l'introduire dans le moule jusqu'à y descendre jusqu'à hauteur des bords de la semelle, définissant ainsi un espace intérieur creux délimité par cette coque ;
  • . puis à fermer le moule à l'aide de son couvercle et à injecter, dans cet espace interne, les composants liquides d'une mousse synthétique qui, en s'expansant, forme le noyau tout en plaquant la coque contre la face interne du couvercle; si les couches précitées sont déjà préassemblées, cette injection se fait à température relativement basse (environ 60 degrés Celsius) dans une première variante de procédé; à contrario, si ces couches sont préencollées, cette injection se fait à température élevée (environ 120 degrés Celsius) dans une seconde variante dite "V.H.P" de ce procédé; après durcissement de la colle puis refroidissement du ski, on le démoule et on procède aux opérations de finition.

Skis are actually currently molded using two very different types of process:

• A first process is the so-called "wet process" which schematically consists of:
  • . first of all to stack, in the open mold, the constituent elements of the ski: the sole bordered by the edges any one or more lower reinforcement layers, the solid core bordered by any edges, one or more upper reinforcement layers, and finally the plastic top (flat or shaped), all of these elements being pre-glued with resin mixed with its hardener but not yet crosslinked or fired;
  • . then to close the mold using its cover under a pressure which, being for example of the order of ten bars, is sufficient to ensure the correct positioning of the elements, and to assemble the assembly in temperature for a predefined time, this temperature being for example of the order of a hundred degrees Celsius, so as to cause the fluidization then the hardening of the resin, and finally the cooking of the whole; after cooling of the structure thus obtained, the mold is opened, the ski is extracted and the finishing operations are carried out.
• A second, more modern, process called "injected form" which consists of:
  • . to place in the open mold the sole, bordered by any edges, and one or more lower reinforcement layers pre-glued or pre-assembled together and with the sole, then the plastic shell pre-assembled to one or more upper reinforcement layers, by arching this shell to introduce it into the mold until it descends to the height of the edges of the sole, thus defining a hollow interior space delimited by this shell;
  • . then to close the mold using its cover and to inject, into this internal space, the liquid components of a synthetic foam which, by expanding, forms the core while pressing the shell against the internal face of the cover ; if the above-mentioned layers are already pre-assembled, this injection is carried out at a relatively low temperature (around 60 degrees Celsius) in a first variant of the process; conversely, if these layers are pre-glued, this injection is done at high temperature (around 120 degrees Celsius) in a second variant called "VHP" of this process; after the glue has hardened and the ski has cooled, it is demolded and the finishing operations are carried out.

It appears from this reminder of the manufacturing processes that in one case, the ski mold is produced at a relatively low temperature, of the order of 60 degrees Celsius, which makes it possible to use, as transparent plastic material, protection of screen printing, an inexpensive compound but of use thus limited due to its low temperature resistance. In the other two cases, on the contrary, the production is carried out at a temperature equal to or higher than 100 ° C., which necessitates choosing, as transparent plastic material for protecting screen printing, a compound having good temperature resistance and the price of which cost is rather expensive.

As another state of the art in ski decoration can also be cited the documents FR-A-2,313,953 and FR-A-2,366,039 which relate to the decoration of a ski by means of successive segments constituted by parts of sheets of synthetic material colored differently in the mass, these segments engaging one another transversely to the longitudinal direction of the ski by means of complementary marginal zones.

As a state of the art in the more general field of protection of particularly attacked areas of a ski, can be cited the document FR-A-2,672,810 which provides openings made in the hull of a ski at the places most exposed to external aggressions, these openings being filled with a deformable and elastic protective plastic foam, itself covered with a membrane.

A second object of the invention is to propose a method of manufacturing a ski, or other board for gliding on snow, as well as to propose a ski or board produced according to this process, which is of an optimized yield according to the real need which constitutes the protection of the decoration of this ski or board.

• . en ce que ce dessus ou coque comprend un complexe multi-couches formé à partir d'un stratifié de couches plastiques planes,
• . et en ce qu'au moins la couche supérieure du stratifié est ajourée ou interrompue en au moins un endroit, définissant ainsi dans ce complexe au moins une fenêtre ou interruption qui laisse voir, sur cette planche de glisse, au moins une des couches sous-jacentes de ce stratifié.

To these effects, the invention relates to a ski, or other board for sliding on snow, comprising a protective or decorative top or shell which is made of plastic, characterized:

• . in that this top or shell comprises a multi-layer complex formed from a laminate of plane plastic layers,
• . and in that at least the upper layer of the laminate is perforated or interrupted in at least one place, thus defining in this complex at least one window or interruption which reveals, on this gliding board, at least one of the layers under adjacent to this laminate.

• . une semelle de glissement éventuellement bordée par des carres,
• . un noyau central,
• . une ou plusieurs couches de renfort,
• . une coque ou dessus plastique de protection et de décor,

ce procédé consistant au moins, de manière en soi connue :

• soit, dans le mode dit "voie humide" :
  • . à empiler, dans le moule ouvert, successivement la semelle, éventuellement bordée par les carres, une ou plusieurs couches de renfort inférieures, le noyau solide bordé par des chants éventuels, une ou plusieurs couches de renfort supérieures, et finalement ledit dessus ou coque plastique, l'ensemble de ces éléments étant préencollé,
  • . puis à fermer le moule à l'aide de son couvercle et sous forte pression, à monter en température, etc...
• soit, dans le mode "injecté forme" :
  • . à placer dans le moule ouvert la semelle, bordée éventuellement par les carres, et une ou plusieurs couches de renfort inférieures préassemblées ou préencollées ensemble et à la semelle, puis ladite coque plastique préassemblée à une ou plusieurs couches supérieures de renfort en arquant cette coque pour l'introduire dans le moule jusqu'à y descendre jusqu'à hauteur des bords de la semelle, définissant ainsi un espace intérieur creux délimité par cette coque,
  • . puis à fermer le moule à l'aide de son couvercle et à injecter, sous forte pression et dans cet espace interne, les composants liquides d'une mousse synthétique qui en s'expansant forme le noyau tout en plaquant ladite coque contre la face interne du couvercle, etc...

et ce procédé étant caractérisé en ce que ce dessus ou coque plastique est, au moins dans sa partie supérieure prise dans le sens de l'épaisseur, réalisé en un complexe multicouches formé d'un stratifié de couches successives, au moins la couche supérieure de ce stratifié présentant au moins une discontinuité réalisée sous forme d'une fenêtre ou interruption qui permet de finalement laisser à nu, après démoulage, au moins un morceau judicieusement choisi d'au moins une des couches sous-jacentes de ce stratifié.The invention also relates to a method of manufacturing a ski, or other board for gliding on snow, using the mold, comprising at least:

• . a sliding sole possibly bordered by edges,
• . a central core,
• . one or more layers of reinforcement,
• . a protective or decorative plastic shell or top,

this process consisting at least, in a manner known per se:

• or, in the so-called "wet" mode:
  • . stacking, in the open mold, successively the sole, possibly bordered by the edges, one or more lower reinforcement layers, the solid core bordered by possible edges, one or more upper reinforcement layers, and finally said plastic top or shell , all of these elements being pre-glued,
  • . then to close the mold using its cover and under strong pressure, to raise the temperature, etc ...
• either, in the "injected form" mode:
  • . to place in the open mold the sole, possibly bordered by the edges, and one or more layers lower reinforcement pre-assembled or pre-glued together and to the sole, then said plastic shell pre-assembled to one or more upper layers of reinforcement by arching this shell to introduce it into the mold until it descends to the height of the edges of the sole , thus defining a hollow interior space delimited by this shell,
  • . then to close the mold using its cover and to inject, under high pressure and into this internal space, the liquid components of a synthetic foam which by expanding forms the core while pressing said shell against the internal face cover, etc ...

and this method being characterized in that this plastic top or shell is, at least in its upper part taken in the direction of the thickness, produced in a multilayer complex formed of a laminate of successive layers, at least the upper layer of this laminate having at least one discontinuity produced in the form of a window or interruption which makes it possible finally to leave bare, after demolding, at least one judiciously chosen piece of at least one of the underlying layers of this laminate.

• . Figure 1 est une représentation partielle, et en perspective, du complexe multicouches qui est préparé préalablement en vue de la fabrication au moule d'un ski conforme à l'invention.
• . Figure 2 schématise la déformation de ce complexe multicouches lors de la fabrication au moule de ce ski.
• . Figure 3 est une vue de dessus de ce ski, réalisé selon l'invention.
• . Figures 4 et 5 sont des vues en coupe transversale de ce ski, respectivement selon IV-IV et selon V-V de Figure 3.
• . Figures 6 et 7 sont des vues semblables à Figures 1 et 3, mais montrant une autre forme d'exécution de ce ski.
• . Figure 8 est une coupe transversale, selon VIII-VIII de Figure 7, de ce dernier ski.
• . Figure 9 est une vue semblable à Figure 8, mais montrant une variante de réalisation.
• . Figure 10 est une vue semblable à Figure 1, et montrant une autre forme de réalisation de ce complexe multicouches.
• . Figure 11 est une coupe longitudinale du complexe multicouches de Figure 10.
• . Figure 12 schématise la déformation du complexe multicouches selon Figure 11, lors de la fabrication au moule du ski.
• . Figures 13 et 14 sont des vues respectivement semblables à Figure 10 et 12, mais montrant une autre forme de réalisation de ce ski.
• . Figures 15 et 16 sont des vues respectivement semblables à Figures 10 et 12, mais montrant encore une autre forme de réalisation de ce ski.

The invention will be clearly understood, and its advantages and characteristics will emerge more clearly from the following description of a few non-limiting exemplary embodiments, with reference to the appended schematic drawing in which:

• . Figure 1 is a partial representation, in perspective, of the multilayer complex which is prepared beforehand for the manufacture in the mold of a ski according to the invention.
• . Figure 2 shows schematically the deformation of this multilayer complex during the manufacture of this ski in the mold.
• . Figure 3 is a top view of this ski, produced according to the invention.
• . Figures 4 and 5 are cross-sectional views of this ski, respectively according to IV-IV and according to VV of Figure 3.
• . Figures 6 and 7 are views similar to Figures 1 and 3, but showing another embodiment of this ski.
• . Figure 8 is a cross section along VIII-VIII of Figure 7, of the latter ski.
• . Figure 9 is a view similar to Figure 8, but showing an alternative embodiment.
• . Figure 10 is a view similar to Figure 1, and showing another embodiment of this multilayer complex.
• . Figure 11 is a longitudinal section of the multilayer complex of Figure 10.
• . Figure 12 shows schematically the deformation of the multilayer complex according to Figure 11, during the ski mold manufacturing.
• . Figures 13 and 14 are views respectively similar to Figure 10 and 12, but showing another embodiment of this ski.
• . Figures 15 and 16 are views respectively similar to Figures 10 and 12, but showing yet another embodiment of this ski.

Referring to Figures 1 to 5, this is a first embodiment of a piste ski 1 (Figures 3 to 5) for which provision has been made to protect the screen printing with a fairly thick layer 2 of plastic material transparent.

According to a particularly interesting aspect of the present invention, this protection by the transparent plastic layer 2 is only provided on the front part 3 and on the rear part 4 of the ski, that is to say only upstream and downstream a central zone 5 which includes the shoe zone 6 which supports the bindings.

To fix ideas in a nonlimiting manner, this central zone 5, for which the screen printing is not protected by the transparent plastic layer 2, has a length of the order of 550 to 600 millimeters, and it extends slightly close symmetrically on either side of the skate area.

In fact, this central zone 5 defines a breach, or interruption, of the transparent and protective plastic layer 2.

Of course, the screen printing is not protected in this zone 5, except by a thin layer of traditional varnish, but on reflection this is not a real disadvantage because experience shows that this screen printing is not practically never attacked in this central zone 5 since it is in fact protected by the shoe.

The skiing according to these Figures 3 to 5 is carried out as follows:

We start by making, for example by the plastering technique, a long multilayer complex 7, here with only two layers comprising a lower layer 8 of opaque and resistant plastic, for example ABS, and an upper layer 2 of transparent plastic and protective.

By producing this two-layer complex 7, a longitudinal and substantially central interruption 9 is provided in the transparent upper layer 9 which constitutes the abovementioned central zone 5.

The dimensions (length and width) of this bilayer complex 7 are chosen to be sufficient so that it can constitute, after manufacture of the ski 1 in the mold, the shell 10 of the ski 1, which is therefore a "ski-shell" in this example.

The decoration of the upper face of the ski was of course carried out, by a known technique such as a screen printing, before the assembly of the two layers 8,2 of the bilayer complex 7. It may for example have been made either by screen printing on the upper face of the ABS layer 8, either by interposing a predecorated veil, as described in the document FR-A-2,660,251 cited above.

The ski 1 is then molded, for example by the now conventional method known as "injected form".

For this, the upper reinforcing fabric 11 (FIGS. 4 and 5) is firstly glued under the two-layer complex 7.

The sole is placed successively in the open mold 12, the metal edges 13, and the lower reinforcement 14.

These elements are glued to each other by resin mixed with its hardener but not yet cooked.

The shell 10 is then introduced into the mold until it comes to bear on the edges 13. It does not, at this stage, have its final shape.

The mold cover is then closed, then the interior is heated either to about 60 ° C in the simplest process mentioned above, or to about 120 ° C in the V.H.P. process. Then injected polyurethane foam which, once hardened, will form the core 15 of the ski.

The pressure P exerted by the polyurethane foam during the injection then presses the shell 10 against the walls of the mold cover, so that this shell 10 takes its final shape.

This pressure P also comes, at the location of the opening 9, to deform the layer 8 of ABS to bring it, at this location, to the same level as the transparent layer 2, as shown schematically in FIG. 2 At the location of the interruption or breach 9, the lower layer 8 of the bilayer complex 7 therefore "rises", under the effect of the pressure P exerted by the polyurethane foam during the injection of the core 15, in this opening 9 to finally be placed at the same level as the transparent upper layer 2.

After cooling and demolding, the conventional sanding, deburring and more generally finishing operations of the ski 1 are carried out.

Note that this embodiment of a ski 1 by a modern process called "form injection" is illustrative and not preferential. In the case of making a ski by the traditional mold manufacturing method under high pressure and temperature, the core then not being injected but prefabricated, the same deformation is obtained, according to Figure 2, of the lower layer 8 planning everything simply place an additional reinforcement layer 16 (in dotted lines in FIG. 2) in the mold which has substantially the dimension of the opening 9, this layer 16 being placed under the laminate 7. When the cover is closed, it pressure P is exerted from top to bottom on the laminate 7, this pressure being around ten bars to fix ideas. This pressure then comes to press on the transparent layer 2 on either side of the opening 9, and thereafter "push" this layer 2 to finally force it to descend to the level of layer 8 at the location of the opening 9: the configuration of Figure 2 is then obtained also in such a case.

Note that the opening 9 can have other dimensions, shape, and location, and that there can be several openings of this type, causing the most varied aesthetic effects, and in this regard Figures 6 to 14 show some other examples of realization among many others.

Figures 6 to 8 illustrate a variant of the ski 1 previously described, for which the screen printing is protected by the transparent plastic layer 2 only on the front and rear edges of the ski, always only in front and behind the central area 5 cited above. The opening 9 of the layer 2 then includes not only the central zone 5, but also the front longitudinal 17 and rear 18 longitudinal zones of the ski. An even more economical embodiment is then obtained, the transparent layer 2 being narrowed to the minimum necessary to protect the screen printing from external shocks, and of an even more striking aesthetic effect.

Figure 9 is a view similar to Figure 8, but for which, following a corresponding shape of the mold cover used, the rear middle and / or front 18 overhangs.

Figures 10 and 12 illustrate, by comparison with Figures 1 and 2, an alternative embodiment of ski 1 for which is provided, in addition to the aforementioned central opening 9, at least one other opening 19 in the layer 2 which is constituted by a window. After the ski has been molded (Figure 12), the ABS layer 8 is also "mounted" in window 19 to reach it at the same level as layer 2.

This not only gives a pleasant aesthetic effect, but also marks the location of the window 19 in the location of an internal technical element of the ski, for example a vibration-absorbing plate.

Note that so far there has been talk of an upper transparent layer 2 and a lower layer 8 tinted in the mass, because we have so far focused on the problem of protecting screen printing. The invention is however not fixed in this kind of embodiment. The two layers 8 and 2 can both be tinted in the mass, while being visually of different colors, and then the aesthetic effect obtained by an embodiment according to the invention, for example according to Figures 1 to 12, is particularly striking. Likewise, the two aforementioned layers can be reversed, the upper layer 2 being tinted in the mass while the lower layer 8 is transparent. We can then see by transparency of the technical elements of the ski body: by considering Figure 12 for example, we can see in this case the plate intended for the screwing of the bindings at the location of the central opening 9, and for example a vibration damping plate under window 19.

By comparing Figures 13 and 14 to the embodiment according to Figures 1 to 2, it can be seen that one can also obtain, by means of a corresponding shape of the mold cover, an embodiment for which the pad area 6 is raised relative to the surface of the ski. The plate 20 into which the fasteners are screwed then passes through the opening 9 of the upper plastic layer 2.

The multilayer complex 7 can also have more than two layers and, in this regard, Figures 15 and 16 illustrate, by comparison with FIGS. 10 and 12 for example, an interesting embodiment for which this laminate 7 is composed of three superimposed layers, including a lower layer 21 of transparent plastic, an intermediate layer 8 of mass-dyed ABS, and an upper layer 2 made of transparent plastic.

In such a case, the window 19 is cut both in the upper layer 2 and in the intermediate layer 8. In the mold, a technical element 22, such as a vibration damper, is placed under the window 19, the underside of the mold is left flat, that is to say without prominences, so that after demolding, the result obtained is that of Figure 16: the technical element 22 is mounted in the window 19, while in this window 19 the transparent lower layer 21 is mounted at the same level as the transparent upper layer 2, that it somehow continues. At the level of the window 19, we see by transparency the technical element 22, which is well protected by the layer 21, while the screen printing visible on the layer 8 is well protected by the transparent layer 2.

It goes without saying that the invention is not limited to these few examples of applications. The number of layers of the multilayer complex 7 can be greater than three, the openings can be very varied and made, in one place, on a number of judiciously chosen layers. The colors of the different layers of the laminate 7, and their transparency or not, can be very varied, so that the aesthetic and technical effects thus obtained can be varied endlessly.

Claims (15)

1 - Ski or other board for sliding on snow, comprising a top or shell (10) for protection and decoration which is made of plastic, characterized: . in that this top or shell (10) comprises a multilayer complex (7) formed from a laminate of flat plastic layers (8,2), . and in that at least the upper layer (2) of the laminate is perforated or interrupted in at least one place (9,19), thus defining in this complex (7) at least one window (19) or interruption (9) which reveals, on this gliding board (1), at least one of the underlying layers (8) of this laminate (7). 2 - Ski or other board for gliding on snow according to claim 1, characterized in that said upper layer (2) of the multilayer complex (7) is a transparent plastic layer for protecting the decoration of this board for gliding (1). 3 - Ski or other board for sliding on snow according to claim 2, characterized in that this transparent plastic layer (2) is at least interrupted in the central zone (5) which comprises the skid zone (6). 4 - Ski or other board for gliding on snow according to claim 3, characterized in that this transparent plastic layer is also interrupted in the median longitudinal regions of the front (17) and / or the rear (18) of the board (1). 5 - Ski or other board for gliding on snow according to any one of claims 1 to 4, characterized in that the lower layer (8,21) of the laminate (7) arrives in the openings (9) or windows (19 ), at the same level as said upper layer (2). 6 - Ski or other board for sliding on snow according to any one of claims 1 to 4, characterized in that the lower layer (8,21) of the laminate (7) arrives, in the openings (9) or windows (19), above said upper layer (2). 7 - Ski or other board for gliding on snow according to any one of claims 1 to 6, characterized in that the multilayer complex (7) comprises more than two layers (21,8,2), in that the upper layer (2) and the lower layer (21) of this multilayer complex are both transparent, and in that at least one of the openings or windows (19) is cut in all the layers (8,2) which cover this lower layer (21), so that finally said transparent upper layer (2) protects at least a portion of the decor of the board, while said lower layer (21) lets see and protects a portion (22) of the internal part of the ski. 8 - Ski or other snow gliding board according to claim 7, characterized in that this portion of the internal part of the ski comprises a technical element (22) of the ski, such as for example a vibration damping plate or a plate intended when screwing the fasteners. 9 - Ski or other board for sliding on snow according to claim 7 or claim 8, characterized in that, at the place of said openings or windows (19), these two transparent layers (2,21) are at the same level, one (21) somehow continuing the other (2). 10 - Ski or other board for sliding on snow according to any one of claims 1 to 9, characterized in that at least the upper layer (2) of the multilayer complex (7) is visually different from the other layer (s) ( 8) of this multilayer complex. 11 - Ski or other board for sliding on snow, the decoration of which is protected by a transparent plastic layer (2), characterized in that this protection by said transparent plastic layer (2) is only provided on the front part (3) and on the rear part (4) of the board (1), that is to say upstream and downstream of a central zone (5) which includes the skate zone (6). 12 - Ski or other board for sliding on snow according to claim 11, characterized in that this protection by transparent plastic layer (2) is also not provided in the median longitudinal regions of the front (17) and / or from the back (18) of the board (1). 13 - A method of manufacturing a ski (1), or other board for gliding on snow, according to any one of claims 1 to 12 and comprising at least: . a sliding sole (12) possibly bordered by edges (13), . a central core (15), . one or more reinforcing layers (14,11), . a protective or decorative plastic shell or top (10), this process consisting at least, in a manner known per se: - or, in the so-called "wet" mode: . stacking, in the open mold, successively the sole (12), optionally bordered by the edges (13), one or more lower reinforcement layers (14), the solid core (15) bordered by possible edges, one or more upper reinforcing layers (11), and finally said top or plastic shell (10), all of these elements being pre-glued, . then to close the mold using its cover and under strong pressure, to raise the temperature, etc ... - either, in the "injected form" mode: . to place in the open mold the sole (12), optionally bordered by the edges (13), and one or more lower reinforcement layers (14) preassembled or pre-glued together and to the sole (12), then said plastic shell (10 ) preassembled to one or more upper reinforcing layers (11) by arching this shell (10) to introduce it into the mold until it descends there up to the edge of the sole (12), thus defining a hollow interior space delimited by this shell, . then to close the mold using its cover and to inject, under high pressure and into this internal space, the liquid components of a synthetic foam which by expanding forms the core (15) while pressing said shell ( 10) against the internal face of the cover, etc., characterized in that this plastic top or shell (10) is, at least in its upper part taken in the thickness direction, produced in a multilayer complex (7) formed of a laminate of successive layers (8,2) , at least the upper layer (2) of this laminate (7) having at least one discontinuity produced in the form of a window (19) or interruption (9) which makes it possible to finally leave bare, after demolding, at least one piece judiciously chosen from at least one of the underlying layers (8) of this multilayer complex (7). 14 - Method according to claim 13, executed according to said "injected shape" mode, characterized in that, in order to obtain a uniform level for the upper surface of this board (1) despite the presence of said discontinuities (9,19 ), the internal face of the cover is of uniform surface, so that during the injection of the core 15, the pressure (P) due to this injection comes to stretch, in these discontinuities (9,19) the lower layer (8) of the laminate (7), this lower layer (8) "rising" then in each of these discontinuities (9,19) to finally arrive, on the finished board, at the same level as the upper layer (2) of the laminate. 15 - Process according to claim 13, executed according to said "wet" mode, characterized in that, in order to obtain a uniform level for the upper surface of this board (1) despite the presence of said discontinuities (9,19 ), an additional reinforcing layer (16) is placed in the mold under each discontinuity (9,19), this additional layer (16) being substantially the same dimensions as the corresponding discontinuity (9,19).

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