DESCRIPTION

Waterproof Aseptic Composite Panel in Lightweight Marble.

The invention presents a method and a product for solving the problems connected with water or other fluids infiltration and stagnation presently complained in coverings or linings made with lightweight marble, especially in bathrooms and shower rooms.

TECHNICAL FIELD

The invention finds use and application in the field of producing and installing lightweight stone linings and coverings (lightweight marble), employed in the general building and furniture industry and more specifically in the naval sector, by proposing a favorable solution to problems due to water and other fluids infiltration and stagnation, which can arise in many settings but mainly in linings and coverings of bathrooms and shower rooms. BACKGROUND ART

The lightweight marble is a product, used mainly for linings, which is made by coupling a thin sheet of stone with a strong layer of lightweight structural material: the product binds together the good esthetical and functional properties of the stone with the strength of lightweight structural material. The practical consequences of this coupling are in the possibility of better shaping and working the stone, when necessary, and a better, more favorable and reliable use of it in linings, whenever the lightweight is a looked for and required property.

In recent developments, the structural material most favorably applied in lightweight marble is in a cellar form, like the cells in a bees nest, made with aluminum alloys or other suitable metals, generally known as honeycomb; but also other light structural materials are employed, like ply wood, layered wood, plastic foams or others. Innovation is very fast in this industrial sector; a few recent developments are patented. (See for example international patent No. WO 2009/060492 by this same proponent).

The lightweight marble linings are presently mainly manufactured with forms, dimensions and specifications aimed to specific applications, but the tendency is growing towards standard forms and dimensions, as seen in usual marble coverings and tiles. The ways and means adopted in order to apply and fix lightweight marble on the walls tend to be similar to the ones used in the marble sector but due to lightweight and peculiar features, also methods are proposed, used in other industrial branches like, for fixing wood panels on walls and structures, in the furniture sector, where means for hooking and fixing, for example by snaps and springs, are very apt and efficient.

By the widening of use and application of lightweight marble, special problems arise, which need to find a practical solution. Like the ones caused by water or other liquid materials stagnating inside or under the linings, therefrom harmful effects can arise, for example weakening or rupturing of the structure, through changes in the physical state of water and fluids, under circumstances; and harmful or noxious effects on the fenvironment caused by development and decay of organic materials near or inside the stagnating liquids. These problems did especially arise in shower rooms of ships: under the shower floor, which is usually located upon a tray bilge, and beneath the wall linings; especially in cases where honeycomb is used as structural material, where water or other fluids can reach the open cells of the honeycomb, and the space beneath, and there stagnate.

But the said problems arise in general wherever the structural material of lightweight marble is not waterproof or made such (it should be noted that marbles and other stones can hardly protect the underlying structure from infiltration, being themselves in most case not watertight).

Therefore these problems arise in general with the lightweight marble linings now in use, implying severe limitations to their general use, especially in bathrooms and shower rooms, mainly in the naval sector.

These problems have not jet been practically and efficiently solved: a new and effective solution thereof consists in the product and method here presented and proposed.

DISCLOSURE OF INVENTION

The problem of stagnation of fluids has its solution in making it difficult for the stagnation to arise and, should it anyway arise, in removing it.

This inventor has developed a shower platform easy to inspect in its interior and under it. The said platform consists in a block of light and waterproof material where, on its upper face, ways , open channels and holes are carved. This platform rests, in a ship, on the structure called tray bilge and has its under face adapted in such a way to the form of the said tray bilge that it rests firmly upon it. On its upper face, the said platform features ample surfaces, for supporting a slab of light material covering it, and channels, on its borders and internally, for collecting and discharging water. It happens therefore that the water, after falling on the slab covering the platform, reaches its border (and discharge holes possibly bored in the slab itself), falls in the lateral and internal channels of the said platform, is from them collected and runs, trough the ways, channels and holes carved in the platform, towards the discharge. Platform and slab are easy to inspect: the inspectability being secured by the mode of construction, where platform and slab simply rest, respectively on the tray bilge and upon the platform itself; being applied in form but not fixed in a permanent way (the ease of inspecting being secured by the lightweight both of the platform and of the slab). The slab can be easily lifted, for example, but not necessarily, by means of suction cups, exposing by that the ways and channels carved on the platform; the platform itself, for simply resting on the tray bilge and being made of light material can also be easily lifted, in order to be inspected and cleaned, and thereby making it possible to inspect and clean also the exposed tray bilge.

But the water can also stagnate inside some of the light materials used for building the said slab and platform: for example, in a lightweight slab built with a honeycomb structure, water can seep and enter in the open cells. It is J

therefore advised to avoid such materials for these applications, and use instead light materials with tight closed cells or, anyway, characterized by a low water absorption coefficient. Available in the market are many materials, produced in slabs, with the above said features. Following extensive research and experiments, rigid polyurethane high density foams came out as the best suited materials for the said applications.

In the following description of this invention, polyurethane foam will therefore be mentioned, for the sake of clarity, without however ruling out other products which could be also favorably used like, for example, high density polystyrene, or others.

The polyurethane foam shows, in some products, good properties from the view point of withstanding compression, but generally bad properties in withstanding flexion. If, however, on both faces of a polyurethane foam slab a textile net or fabric is glued (for example a fiberglass fabric), the resulting material shows remarkable improvement of physical properties especially in increasing flexion stress resistance. These properties are further enhances by making, on the faces of the polyurethane slab, holes and grooves of suitable depth and size, uniformly or anyway suitably located: the glue connecting the slab to the fabric will enter those holes and grooves and "nail" the fabric to the slab itself. The resulting body will be characterized by very high resistance to flexion and also to tear. The above described construction method shows a way for producing excellent reinforcing structures for lightweight marble slabs; and also blocks of stratified material. Such slabs of lightweight marble can therefore be used as covering slabs on the floor of showers described in this invention. And can be advantageously used as linings and coverings in the walls of a shower room (where problems of water infiltration and stagnation, anyway in a lesser degree, can also arise). In this special use, the back face of the lightweight of the marble slab, reinforced (and further waterproofed by the fabric glued on it) is very apt to lodge, or anyway firmly held, systems of hooking end disengaging, for example of the snapping type, widely employed in other industrial sectors, like carpentry and furniture, for fixing panels upon walls or bearing structures.

Along the polyurethane borders of such lightweight marble slabs, it is possible to carve continuous grooves for receiving thin continuous blades of flexible or hard materials to be used as washers or connecting slabs: the said blades, functioning as washers will avoid water seeping or infiltration, towards the wall, through the border of the slabs; functioning as connecting device, the same will increase the interconnection between the slabs and achieve their firmer positioning. The adoption of the said blades along the borders and of the said hooking and unhooking devices on the back of the slabs, will secure their firm staying in place, their easy removal for needs of cleaning and inspection, end their easy reinstating in place.

This inventor is well aware of the fact that this invention, born in order to solve problems connected with water infiltration, has more general use and application, also in settings with no water implied, being characterized not only by proposing a solution to water infiltration but also a solution to the problem of easy placement, removal and replacement, of coverings and linings in lightweight marble. This last feature, not rare with removable wood panels used as coverings in furniture, was never seen, up to now, in stone or marble linings.

BEST MODE FOR CARRYING OUT THE INVENTION

This invention, which solves the problems due to stagnation of water or other fluids in lightweight marble linings and coverings, has found an exemplary use in the shower rooms of a ship.

For this use, two types of lightweight marble slabs have been built: a stratified slab, with thickness and flexional strength properties such as to enable it to be used as the plate covering the discharge channels on the floor; and the simple slabs to be used as linings on the walls. In both cases the core material is high density polyurethane foam. This material is available in different geometrical shapes and a variety of chemical and physical properties, of which the most favorable where chosen for the specific application. On both faces of the polyurethane slabs, holes have been bored for obtaining the above mentioned "nailing" feature; on both faces of the slabs liquid epoxy resin has been applied, upon which a strong fabric of fiberglass, also imbibed with resin has been put. On the external face of slab covered in such a way, a sheet of marble has been applied, already of the required shape thickness and finishing, or such as to be later worked to the proper shape of a lightweight marble slab. All this, in a controlled low pressure atmosphere, uniformly compressed, heated to a given temperature, and held in an oven, under stable and controlled physical conditions, for the right time to reach the best maturing of the resin. To the resulting product the necessary workings, trimming and polishing, have been applied, in order to achieve the standards of a well finished lightweight marble slab.

Along the border faces of the slabs, cut to measure in order to be used for the lining of the shower walls, longitudinal grooves have been carved for receiving blades of lightly flexible washer material (for sealing the borders of the slabs but also for holding them in place with a strong but not rigid grip); on the back of the slabs hooking devices have been applied which, snapped and coupled together with their counterparts fixed on the wall, allow the strong positioning of the slabs upon the wall itself (and their easy removal, when necessary, for inspection, cleaning of the back space and repositioning, or replacing, when necessary).

In a particularly demanding case, on the external border of the slabs, silicon sealing material has been also applied and, on the wall, confronting the internal borders of some slabs, stripes of soft rubber have been glued, in order to further seal the occasional gaps and also to damp vibrations (quite common in a ship). The slab on the floor, stratified for greater strength (but could have been simply thick enough for the use), and build following the above described procedure, was laid to rest on its lodgings, on the base underneath the shower, which is worked in such a away as to receive and collect the water falling from the borders of the slab on the floor slab and to channel it towards the discharge.

The said base underneath the shower is a thick block made of slabs of high density polyurethane stratified with strong fiberglass cloth and glued together by means of epoxy resin matured in the above mentioned controlled conditions. The lower face of the block has been worked in such a way as to rest in place on the shape of the tray bilge. On its upper face wide surfaces are available for the floor plate of the shower to rest upon and open channels and chutes are carved in order to collect and channel the waters towards the discharge.

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