CENTRAL FOAMED LAYER AND MINERALIZED COATING

[0001] The present invention relates to an insulating and protective panel for construction with central foamed layer and mineralized coating.

Field of application [0002] The invention is specifically intended for use in the building industry and particularly in the sector of semi-finished components for construction such as, by way of non-limiting example, insulating panels and/or infill panels. More in detail, an insulating panel is proposed of expanded and/or extruded polystyrene or of expanded polyurethane, which has particular surface layers for coating and protection, which are symmetrically coupled on both faces making the panel rigid and self-supporting, waterproof, resistant to damp and to fire, and also provided with an improved adhesion to glues and/or cement mortars. Therefore, the panel disclosed in the invention is usable as a thin and lightweight constructive element which insulates and waterproofs, and also supports the direct gluing of tiles in damp environments, such as for example in the case of bathrooms, saunas, laundry rooms, or kitchens. By way of example only, it is suitable for making walls, infill walls, floors, floorings or spaces for insertion of bathtubs and showers, or seats or niches integrated in the walls of modem bathrooms coated with ceramic tiles.

[0003] Generally, in the field of construction products panels for thermal insulation, otherwise called non-conductive or insulating panels, are widely known and widespread, which are made up of a rigid and inexpensive material, having an extremely low weight but a highly non-conductive performance, such as expanded polystyrene or extruded polystyrene, otherwise called by the acronyms EPS and XPS. Generally, said EPS or XPS panels are single-layer panels, having a thickness of between 2 cm and 20 cm, and their opposite main faces are smooth and parallel one another, having constant thickness; some solutions provide the external main faces coated with a protective fdm in different materials, such as for example a paper sheet or a plastic plate or a non-woven fabric.

[0004] It has been further found that said expanded EPS or expanded-extruded XPS polystyrene is extremely advantageous for various aspects: for performance, productive, economical, and recyclability aspects; however, it has problems when it is used as material for construction panels, according to the specific aims of the present invention. A first problem concerns its poor resistance when used with structural functions, such as a constructive element of walls, partitions, infill walls or as support for ceramic coatings, plasters, or any surface finishing for environments. In fact, a conventional EPS or XPS panel has a low resistance to bending and to damp and has a surface which is not suitable for the grab of glues or cement mortars commonly used. It has also been found that its surface tends to crumble or crash when accidentally under bending stress in construction sites, or during transport. A further problem concerns its limited resistance to fire and to high temperatures; despite being treated with flame retardants, when subject to high temperatures such a manufacture sublimates and loses its structural integrity. [0005] Generally, in order to overcome such disadvantages, in conventional and known solutions, said EPS or XPS panels are covered with the cited protective films, such as a paper sheet or a plastic plate or a non-woven fabric. Additional layers are also known, which are fire resistant, non-flammable or in any case suitable for retarding combustion; by way of example only, in the vertical walls of buildings such protective layers are made of plasterboard, fiber cement, magnesium oxide, wood cement or with a layer in rock or glass wool so as to completely coat the panel or at least its side edges, since they are the preferred combustion priming zone. Protective sheets made of metal or cement are also known, which are applied on the outer surface of the panel. However, it is known that manufactures made with such added layers have a high thickness, a remarkable specific weight, processing and cutting difficulties, hygroscopicity, poor dimensional stability, low tensile strength, and high costs.

[0006] Recently, companies operating in the construction sector have provided to improve said insulating panels in expanded or extruded polystyrene by means of new additive chemical compounds, or of innovative external protective layers, so as to further increase the thermal insulation characteristics or to reduce the thickness and also, in particular, to improve the fire reaction, so as to exceed the latest provisions. By way of example only, expanded polystyrene comprising graphite particles is known, which are suitable for offering a reduced thermal conductivity, limiting the thickness provided for insulation, and are also suitable for adsorbing and reflecting infrared rays, such as the material marketed under the name Neopor® of the German company Basf SE, Ludwigshafen - www.basf.com, having a thermal conductivity of 0.031 W/mK and a density of 18 kg/m ³ . Furthermore, the use of a particular type of graphite is also known, which is called expandable graphite, which increases its volume at high temperatures, creating a protection barrier against fire; it is sometimes added in varnishes or adhesives. [0007] Alternatively to said XPS and EPS polystyrene, other foam materials are known and widespread, which are suitable for making panels and offer a good insulation capacity but are sometimes disadvantageous due to mechanical characteristics and/or of resistance to bending or damp and/or of long-term durability and/or for production reasons. By way of example only, it is reminded that expanded polyurethane offers a good insulation capacity, but it has to be adequately protected; moreover, in the production phase it requires a higher quantity of primary energy than said polystyrene and is not easily recyclable. However, said expanded polyurethane is a suitable material for the panel proposed in the present invention, being particularly coated.

[0008] More in detail, regarding the specific field of application of the proposed solution, in the sector of interior architecture there is a need for new materials and/or constructive elements suitable for rapidly making walls and subfloors, with reduced weights and costs compared to traditional materials as bricks made of clay or cement, or compared to the reinforced concrete works, or also compared to the conventional plasterboard panels. Particularly, professionals require versatile and lightweight constructive elements, shaped like rigid and thin panels, provided with a high resistance and to bending and damp; moreover, panels are required which are able to ensure a good adhesion to glues and to cement mortars. Essentially, there is a need of a self-supporting panel, which is easy to transport and to cut in the construction site by a single person according to need, this panel being rigid and suitable for supporting the laying of tiles, also in the presence of water and/or damp.

[0009] Particularly, new solutions of self-supporting and waterproofing panels are needed, which allow to make in an easier and more inexpensive way compared to said bricks, and also in a safer and more durable way compared to conventional plasterboard, any configuration of wall, niche, shaped space, floor or subfloor located in damp environments and coated with tiles, as in the case of bathrooms, saunas, laundry rooms and kitchens. By way of example only, it should be taken into consideration the frequent need to obtain spaces for the insertion of bathtubs and showers in bathrooms, or niches integrated in the walls, where said spaces and niches are made in the construction site according to a design provided by the designer, in line with the side walls and coated with the same tiles. Together with said requirements, there is also a need for an insulating panel for damp environments, which can be directly coated with tiles.

[0010] Among the most widespread and advantageous known solutions there are multifunctional insulating panels made up of a foamed core in a lightweight insulating material, such as expanded polystyrene or expanded polyurethane, with a waterproofing and hardening multi-layer coating which is symmetrically glued on both faces, like a sandwich panel. Generally, this superficial coating is made up of various layers having diversified functions and being combined one another, so as to obtain an insulating panel which is resistant to damp and bending and is usable as a constructive element to make up infill walls, niches or floors, also in damp environments such as bathrooms and saunas. Particularly, some panels provide a further outer layer which improves the grab of glues or cement mortars, so as to support the gluing of tiles or plasters directly laid on the panel surface.

[0011] Therefore, it has been found that in this advanced type of insulating panels, said multi-layer coating consist on the whole of at least three layers, with a waterproof layer such as a plastic plate or a waterproof paper, which is coupled to different permeable layers placed over and/or under to it, so as to facilitate the gluing and also to increase the structural rigidity, such as for example a non-woven fabric made of plastic fibers and/or a net. By way of example only, it is reminded that the multi-layer panel named Kerdi Board by the German company Schluter- Systems KG, D-58640 Iserlohn www.schlueter.de is suitable for making bathrooms and shower spaces. Currently, this type of insulating panels with structural and waterproofing function for damp environments is widely used and appreciated as it considerably facilitates the work in the construction site compared to traditional materials, such as clay bricks or plasterboard sheets.

[0012] It has been further found that in the interior architecture rigid sheets made of plasterboard or of other cement-based materials are widely used, which are possibly coupled to other layers according to need. Such sheets have good structural characteristics and a smooth surface, ready to be coated with tiles or plasters; however, they are not suitable for the aim of the invention, being disadvantageous during transport and working in the construction site, due to their heavy weight and the dust released during the cutting phase; moreover, they are not very suitable for installations where there is a high presence of water and/or vapor, such as in bathrooms and saunas.

[0013] Alternatively, for laying tiles in damp environments insulating panels having a good compatibility with cement glue for tiles are also known and ensure a greater resistance to tearing compared to the above-mentioned multi-layer insulating panels. These panels have a lightweight core made of a foamed plastic material and are provided with a multi-layer and composite coating, generally glass fiber- based, which externally comprises a thin mineral and/or cement layer facilitating the application of a finishing and/or the laying of tiles. However, they have some disadvantages, such as the known problem of cement dust release during the cutting phase in the construction site, in addition to a high production complexity.

[0014] Essentially, in the construction sector an innovative insulating and waterproofing panel for damp environments is required, which can be produced with low costs and high productive volumes, is lightweight, resistant, usable as a workable and safe constructive element and provided with an outer surface allowing the grab of a common cement mortar for tiles with high resistance to tearing. Moreover, such a panel is also required to be able to resist to high temperatures and to protect from fire.

State of the art

[0015] In order to determine the state of the art related to the proposed solution, a conventional verification has been carried out examining public archives, which led to the identification of the prior art cited below: Dl: US8703632 (Shlueter)

D2: US6715249B2 (Rusek et al.)

D3: W02004022335 (Taylor et al.)

D4: W09633866 (Atevic)

D5: US2011217516 (Wedi) D6: US2011225918 (Wedi)

[0016] Dl proposes a waterproofing and hardened sandwich panel with an insulating core in a damp-resistant material such as closed-cell foamed polystyrene, on which a first water-resistant layer is glued such as a sheet of waterproof paper or a non-extendable synthetic plate, where a permeable layer such as a fabric, a non- woven fabric or a mesh is glued to the external part, and also provided with a large- mesh net interposed and glued between said paper and said fabric. These three layers glued on both faces harden the structure of the panel and prevent it from deformation once mounted; particularly, the external permeable layers allow the mortar for tiles or plasters to penetrate and anchor.

[0017] D2 describes an insulating and protective panel for covering walls in construction, consisting of an insulating layer which is coupled on the internal side to a coating which makes it particularly rigid and resistant, being formed by a plurality of interwoven high-resistance fibers, for example carbon or mineral or polyamide or Kevlar fibers or fibers of other low-tensile materials, which are crossed together in an oriented way like a non-deformable mesh on the plane; moreover, it is provided that the assembly adhesive can at least partially penetrate into the interstices between the fibers so as to firmly anchor the panel to a load- bearing structure. In a different embodiment, a hardening and protective polymeric coating is glued on the opposite side which also acts as barrier to vapor and damp, being made of a first polyethylene plate and a second polyester plate with an interposed hardening net which is also made of a plastic material.

[0018] D3 proposes a panel for construction consisting of a polystyrene layer coated with a net-like fabric and a small fiberglass mattress, wherein a cement compound saturates and connects the different layers together, so as to obtain a rigidity and resistance such as to support the fastening elements commonly used in construction, and also to support the laying of tiles directly glued on the outer surface by using commonly used adhesives.

[0019] D4 describes a laminated multi-layer structure with improved fire resistance characteristics, which provides a central layer made of an insulating material and protective layers for coating on both opposite faces like a sandwich panel; they include a fibrous reinforcement layer which is joined to an adhesive layer of inorganic type and an outer layer of an organic resin, wherein said adhesive layer consists of water, magnesium sulphate or magnesium chloride, magnesium oxide and sodium silicate, while said resin is a gel-coat based on modified polyester resin with aluminum hydroxide.

[0020] D5 proposes an XPS panel for construction having a multi-layer coating where the first layer contacts the foamed core and consists of a two-component epoxy resin on which fiberglass is sprayed so as to form an intermediate layer of casually placed and flattened fibers, and with a top layer consisting of a two- component epoxy resin covered with sand sprayed during the hardening phase so as to form a siliceous surface which is ready for the finishing like a rigid layer of glass fiber coated with sand.

[0021] D6 describes multi-layer panel suitable for supporting the laying of tiles, consisting of a central layer in a foam material, such as polystyrene XPS, which is provided with a rigid coating on at least one side, where said coating comprises at least three layers: an adhesive layer toward the central layer, a fiberglass non- woven layer and an external connecting layer made of mortar based on chalk or cement, which is hardened so as to resist to compression and to have a smooth outer surface.

Drawbacks

[0022] Generally, a first problem is related to the fact that in the construction sector there is currently no optimized solution of a multi-layer insulating and protective panel for damp environments, which is contextually self-supporting in order to be used as a constructive element, and resistant to water and damp like a waterproof panel, and also able to resist to high temperatures like a panel for fire protection. [0023] A second problem, which is well-known to the operators of the sector is related to the resistance to tearing of an adhesive for laying tiles, which is sometimes insufficient when they are directly glued on the front face of an insulating panel provided with a protective coating in a cement-free material. More in technical detail, the weak spot is the adhesion interface between the panel coating and the tile adhesive; in fact, the adhesives commonly used for this aim are naturally compatible with cement and/or cement-based materials, such as subfloor screeds, but they are not compatible with the plastic materials generally used in the protective and/or waterproof layers of panels. It has been found that the biggest problem of adhesion in the known and conventional solutions are associated to the presence of a waterproof plate made of plastic, of impregnated paper or of metal, and particularly where said plate is smooth and does not allow an appropriate grab. Such problems are relevant in the case of vertical installations and in damp environments, such as in tiled walls of bathrooms and saunas; on the contrary, the problem of adhesion is less relevant in case of horizontal floors in damp-free environments.

[0024] In this regard, it has been experimentally found that for the most advanced solutions, comprising at least one waterproof layer coupled to at least one permeable outer layer made of a net or a non-woven fabric to facilitate the grab of the cement mortar, such as for example according to Dl, a breaking interface is created on the waterproof smooth layer. On the contrary, panels made of a core which is foamed and reinforced on both sides with a fiberglass fabric, which has been in turn impregnated and covered with a layer of cement mortar, such as for example according to D6 or D3, show a greater compatibility and adhesion with cement glue; however, these panels are not lightweight and easily workable as the above-mentioned panels with waterproof plate of plastic or paper, layers of non- woven fabric and/or nets, having the known problem of dust release during the cutting phase in the construction site, and with lower values in the tests of vapor permeability resistance.

[0025] Furthermore, in this type of panels having cement-based layers some productive difficulties can be found, which are even greater where a rigid supporting layer is provided in glass fiber or similar composites; moreover, they involve high costs. Where sprayed sand is also applied on the panel surface, such as for example according to D5, it is believed that such a solution is not suitable for a modem automated continuous processing cycle where the coating, and/or the single layers it consists of, is provided in a rolled way for the purpose of an automatic coupling to the insulating layer. The protective layer according to D4 is also expensive and complex to produce; moreover, it does not meet all the aims of the present invention.

[0026] Sometimes an inadequate structural behavior has been found in the panels with foamed core and a protective and/or hardening coating which is applied on one side only, or on both sides but in an asymmetrical way, such as for example in D2. In particular, for the purposes of this invention, an insulating panel with asymmetrical stratification and one face covered by ceramic tiles, having a significant weight, can have an inadequate flexural and/or torsional resistance if used as a constructive element which is self-supporting, non-adherent and/or fixed in an integral way to a vertical load-bearing wall or a floor slab. [0027] Moreover, it has been found that known and conventional fire-resistant panels do not offer all the contextually considered advantages of the present invention; moreover, they are generally expensive and difficult to produce.

[0028] Given the above, a new insulating and protective multifunctional panel is required in the construction sector, which is more advantageous compared to the cited solutions and suitable for solving the above-mentioned problems.

Summary of the invention

[0029] This and other aims are achieved by the present invention according to the characteristics of the appended claims, solving the foregoing problems by means of an insulating and protective panel (10) for construction which is resistant to fire and has improved superficial adhesion, made up of a central layer (100) in a foamed insulating and a damp-resistant material, such as XPS or EPS polystyrene or expanded polyurethane, and of a particular mineralized cement-free coating (101, 102) which is joined on both external faces of the central layer (100), forming a symmetrical sandwich structure. The mineralized coating (101, 102) is a multi layer composite, made up of a mineral layer (105) as outer finishing, a supporting layer (106) acting as a reinforcement with an impregnating adhesive which binds the mineral aggregates, and a possible vapor barrier (107) with high water- and gas- resistance; it is provided that at least the mineralized coating has on the front side (102, 110) the scratched outer surface (103), so as to optimize the grab to common glues or cement mortars for ceramic tiles.

Aims [0030] In this way, through the considerable creative contribution whose effect constitutes an immediate technical progress, several advantages are achieved.

[0031] A first aim of the invention is to obtain an insulating multi-layer panel which is extremely resistant, rigid, and self-supporting, having a low weight, so as to be usable as a constructive element for building in an easy and inexpensive way the different structures and the completion works which are currently needed in modem interior architecture, particularly in damp environments such as bathrooms and saunas.

[0032] A second aim is to obtain an insulating panel provided with all the above- described characteristics, contextually considered, and which is also provided with a high resistance to fire and/or to high temperatures, so as to act as thermal insulating material and furthermore to limit the propagation of a flame in case of fire, passing a propagation test performed according to the ASTM E84 regulation or tunnel test. [0033] A third aim is to obtain an insulating and waterproofing panel which has no cement layers and is contextually provided with a high resistance to the passage of vapor and of a high resistance to tearing, with at least one outer surface improved for adhesion purposes. Particularly, it is intended to provide the above-mentioned panel with an outer surface where common ceramic coatings or any finishing tile or also a plaster, can be directly applied using glues or cement mortars of the conventional and known type, without the need to interpose films, nets, grab primers or any other material to facilitate the adhesion, and with a resistance to tearing or pull out which is always equal to or higher than 0.2 N/mmq in a test performed according to the EN 1348 regulation. [0034] A fourth aim is to ensure a safer installation in damp environments where ceramic tiles are glued both on the horizontal plane and on the vertical plane, regardless of their size and/or shape and/or weight, with a greater effectiveness, resistance and global duration compared to similar solutions of insulating panels of synthetic origin.

[0035] A fifth aim is to obtain an insulating panel for construction of the multi layer type and free of cement-based materials, which is very lightweight and easy to transport, to place and to work in the construction site by a single operator using common working tools in the safest way and without releasing dust in the environment; it is therefore suitable for the installation in closed environments.

[0036] A sixth aim is to obtain a multi-layer lightweight and self-supporting panel, which is contextually provided with an optimized structural configuration and is suitable for the laying of tiles. In particular, the described improvement of the superficial adhesion allows to reduce the total number of layers forming the coating of the foamed core compared to the multi-layer conventional and cement-free solutions, wherein a permeable layer is externally provided which is suitable for facilitating the grab of a cement mortar for tiles, such as for example a non-woven fabric, a mesh or a net. The proposed solution, which has no outer permeable layer, allows a significant reduction of global costs and an advantage in the production. [0037] A further aim is to obtain a multi-layer multifunctional protective panel provided with a minimum number of layers, which is waterproof and resistant to fire in the basic configuration, and which can also be highly gas-tight with limited additional costs.

[0038] Therefore, yet another aim is to provide an insulating and protective panel at a reasonable cost which can be industrially worked in an easy and inexpensive way with high production volumes. Consequently, the work in the construction site is remarkably facilitated and it is possible to considerably reduce time and costs for completing a construction manufacture.

[0039] These and other advantages are evident from the following detailed description of a preferred embodiment with the aid of the enclosed schematic drawings whose details are not to be intended as limiting but only exemplary.

Content of the drawings

Figure 1 represents the insulating and protective panel for construction, which is the subject matter of the present invention, in a detailed schematic section not to scale; the dashed rectangle (IV) defines a coating portion which is enlarged in following figures.

Figure 2 represents the same panel of the previous figure, mounted in adhesion on a load-bearing structure and with a layer of ceramic tiles directly glued on the scratched surface of the coating, in a detailed schematic section not to scale.

Figures 3a and 3b schematically represent the superficial scratching of the mineralized coating enlarged under the microscope, with non-through incisions shaped like scratches which are rectilinear and parallel, with other non-through incisions shaped like circular and/or triangular ellipsoidal notches. In a first different embodiment, as in Fig. 3a, said rectilinear scratchings are discontinuous; in a second embodiment, as in Fig. 3b, they are continuous and closer to each other being obtained with a different productive method.

Figures 4a and 4b are enlargements of said sectioned coating, according to the dashed rectangle in Fig. 1 (IV), related to the basic solution, wherein a mineral layer is coupled to a supporting layer acting as reinforcement (IVa, Fig. 4a) and one embodiment with also a vapor barrier (IVb, Fig. 4b).

Practical realization of the subject matter of the invention [0040] Also with reference to the figures (Figs. 1 - 4), an insulating and protective panel for construction (10) is proposed of the self-supporting type, suitable for contextually performing various functions; it is a lightweight non-conductive panel, provided with a high rigidity and resistance to bending, which acts as flat constructive element suitable for making walls, infill walls, floors or subfloors, and which is also suitable for protection against damp and fire. In particular, this invention proposes an advantageous multi-layer panel, which is insulating and waterproof, suitable for installations in damp environments such as bathrooms or saunas, and it is provided with an outer layer which is extremely resistant to high temperatures and it is also mechanically abraded, so as to make the laying of ceramic tiles directly glued thereon more effective and durable, according to the different aims described above.

[0041] It is noted that the proposed insulating and protective panel (10) has no layers of cement-based materials, yet it properly supports the laying of tiles directly glued on its outer surface by means of glues or cement mortars commonly used, without the need for interposing a primer layer, a fabric or a net for grab; therefore, it allows to lay thin tiles of the ceramic or cement type, but it is also suitable for the grab of cement-based plasters or other similar finishing, which are directly applied, ensuring an excellent adhesion with high resistance to tearing both in correspondence with the superficial grab area, and between the internal layers. Said insulating and protective panel (10) considerably facilitates the completion works in indoor environments of buildings, and it is particularly suitable for damp environments with vapor and/or water as bathrooms, saunas, laundry rooms or kitchens; for example, it (10) allows a single operator to rapidly and inexpensively build a whole bathroom coated with ceramic tiles and provided with articulated volumes such as the shower space and wall niches. For example, in a typical installation in a damp environment with the aims of coating and waterproofing (Fig. 2), said panel (10) can be fixed in adhesion to a load-bearing structure (201) such as a masonry or a floor slab, or to a partition of plasterboard or wood, or to any other structure, and on its front face (102, 103) a layer of tiles (202) can be directly glued by means of an adhesive layer (203) of a common glue or cement mortar with the conventional grout lines (204) of tile finishing. Such a solution does not need other materials or additional working.

[0042] Said insulating and protective panel (10) is made up of a central layer (100) in an insulating foamed and damp-resistant material, which has a low specific weight and a high dimensional stability such as XPS or EPS polystyrene or expanded polyurethane, and of a particular coating (101, 102) resistant to damp and fire, which is joined to said central layer (100) on both outer faces and namely a coating (102) on the front side (110) and a coating (101) on the back side (109), forming a symmetrical sandwich structure, wherein said coating protects from impacts and structurally hardens the panel, protects from damp and high temperatures and also increases the resistance to the passage of vapor, making the panel (10) essentially waterproof and suitable in case of fire. Said coating is conventionally called mineralized coating (101, 102), being provided with an external mineral layer (105) with a high density and a thickness higher than 0.2 mm, which is advantageously reinforced by means of a supporting layer (106) coupled thereto in an integrated way and cooperating so as to form a compact and flexible coating, which is extremely effective in protecting from water and from fire and also in blocking the passage of gases. Furthermore, said coating offers a good superficial adhesion for glues or cement mortars commonly used in the laying of tiles, despite being cement-free. In turn, said coating (101, 102) is glued to said central layer (100) by means of a glue layer (104), such as a two-component polyurethane adhesive or an epoxy glue.

[0043] The central layer (100) has a constant thickness and of between 4 mm and 200 mm, with a density ranging from about 15 kg/m ³ to 50 kg/m ³ . In the preferred embodiment, it (100) has a constant thickness and of between 6 mm and 50 mm, a density of about 30 kg/m ³ , with a tolerance of +/- 10 kg/m ³ ; a finished panel (10) (Figs. 1, 2) has an overall thickness about of between 6.6 and 52 mm. However, higher or lower values are suitable for the proposed panel according to a specific application. [0044] With the aim of the invention, it is provided that the most outer layer of the mineralized coating (101, 102) is a fire-resistant mineral layer (105), having a thickness of 0.4 mm with a tolerance of +/- 0.2 mm and a density of between 1000 kg/m ³ and 3100 kg/m ³ . Moreover, it is provided that in at least one mineralized coating (102) this layer (105) has the outer surface (103) scratched and namely provided with various, non-through incisions, also called scratchings, which are shaped like small-sized scratches and/or grooves and/or striations and/or notches or recesses and are uniformly distributed on the whole outer surface of the coating. It is clarified that said incisions or scratchings are essentially deformations and/or removals of minimum portions of material and are obtained by means of superficial mechanical abrasion, acting on the coating from the exterior as described hereinafter. Therefore, in order to ensure the impermeability of the coating, such incisions or scratchings have a depth smaller than the thickness of the material where they are made. In particular, said surface is scratched (103) so as to considerably increase the grab of glues or cement mortars for tiles and plasters, providing the panel with a resistance to tearing or pull-out which is always equal to or higher than 0.2 N/mm2 according to said EN 1348 regulation. In particular, as a clarification, this resistance value also cited in the claims is typical of an insulating and protective panel (10) made such as provided by the present invention (100, 101, 102, 102a, 102b, 103) and it is intended to be referred to the expressly indicated regulation and to the measuring method above described.

[0045] It is noted that said superficial abrasion treatment or scratching (103) is always performed on the coating (102) placed on the side contacting the cement glue (203) which is used to anchor the tile (202), conventionally called front side (110); this solution is advantageous, for example, when the panel (10) is mechanically fixed to a metal frame or a wood framework. Furthermore, the panel (10) can be provided with a scratched surface (103) on both sides (109, 110); this solution is advantageous when it is fixed in adhesion to an existing wall by means of gluing on the back side (109).

[0046] More in technical detail, the mineralized coating (101, 102), in a minimum basic configuration (102a, Fig. 4a), is made up of at least one mineral layer (105) coupled to a supporting layer (106), such as for example pre-coupled. The mineral layer (105) is made up of mineral aggregates in granules and/or in powder, of siliceous sand, quartz, basalt, slate, carbonate, or similar materials; they can be of neutral color or colored with different colors. It is made by laying and then adhering by means of an adhesive on a supporting layer (106) of the permeable type which acts as reinforcement, being it (106) a small net in fiberglass, or a glass film or a polymeric film, preferentially in polyester or polypropylene or a combination thereof, or also a reinforced polymeric film with glass fibers. Said adhesive is an impregnating adhesive, laid in a thin thickness so as to saturate said small net or said film binding and holding the mineral aggregates, and such to form a compact multi-layer element (105, 106), coherent and also flexible having a total thickness of between 0.3 mm and 0.7 mm, and a weight of between 250 g/m ² and 1000 g/m ² , where the thickness of the single mineral layer is of between 0.2 mm and 0.6 mm. For the invention purposes, said adhesive can be an organic adhesive, an inorganic adhesive, an adhesive polymer such as ethylene- vinyl - acetate called EVA or such as styrene - butadiene elastomer, or a bitumen or a polymer-modified bitumen; alternatively, adhesives can be used having equivalent characteristics. [0047] By way of non-limiting example, in an embodiment of the invention said multi-layer element (105, 106) forming a mineralized coating has a total thickness of about 0.50 mm, and a weight of about 300 g/m ² , wherein the thickness of the single mineral layer is of about 0.40 mm; in a different embodiment, having a different combination of aggregates and a different adhesive, the total thickness (105, 106) is of about 0.45 mm, and a weight of about 700 g/m ² , and wherein the thickness of the single mineral layer is of about 0.35 mm.

[0048] The supporting layer (106) comprising said impregnating adhesive makes the mineralized coating (101, 102) compact and coherent, and at the same time flexible like a layered element (105, 106), which is windable, mechanically processable, and durable over time. Once the mineral layer (105) is joined to said supporting layer (106), it performs the combined function of withstanding high temperatures, protecting from flames in case of fire, and also resisting water like a waterproof element, as well as acting as a structural reinforcement, protecting from impacts and also allowing to suitably perform said scratched surface (103), with non-through and well controlled incisions, as described hereinafter.

[0049] In a different embodiment (Fig. 4b), aiming to further increase resistance to the passage of vapor and the impermeability of the panel, it is provided to interpose a vapor barrier (107) between said supporting layer (106) and the foamed central layer (100). Substantially, this barrier (107) is a layer which is possibly added in the stratification of the coating so as to block the passage of gases; in the preferred embodiment of the invention, it is a thin metal sheet, for example an aluminum sheet having a thickness of between 8 microns and 30 microns, or it is a plastic sheet having a thickness of between 0.1 mm and 0.3 mm. In this case, to ensure the material compatibility and resistance to the passing of vapor, said sheet is preferably made of a plastic material of the polyolefin type, virgin or derived from recycling process, or of polyester or of polystyrene, both in the generic version and in the version with high resistance to impacts; for example, the material called by the acronym HDPE, or PP, or also GPPS or HIPS or a mixture thereof is suitable. [0050] Therefore, the above-mentioned vapor barrier (107) is a thin sheet which can be advantageously pre-coupled in the production phase to the above-mentioned layers (105, 106) of the mineralized coating (101, 102), forming a single multi - layer coating (102b, 105, 106, 107) (Fig. 4b) which is windable and mechanizable similarly to said minimum basic configuration (102a) (Fig. 4a), and which can be then being joined (102b) in the same way to the central layer (100, 104), obtaining a waterproof and also gas-tight panel (10) with a water vapor permeability degree or perm rating which is lower than 0.1 measured according to the ASTM rule E96 method E. [0051] Said mineralized coating (101, 102, 105, 106, 107) of the insulating and protective panel (10, 103) provided by the invention can be industrially continuously produced and with high productive volumes, according to a productive process which comprises the following steps (F1-F9):

FI) a first phase for unwinding the supporting layer (106) in the form of a reinforcing film;

F2) a second phase for impregnating the supporting layer (106) with the impregnating adhesive, laid with an ink roller on the face facing the mineral layer (105);

F3) a third phase for scattering the mineral aggregates in granules and/or powders over the impregnated surface of the supporting layer (106), progressively forming the mineral layer (105) by fall, recovering and re circulating the granules and/or powders not adhering to the surface;

F4) a fourth phase for pressing and drying the impregnating adhesive, firstly by means of a passage through press-rollers generating heat, and then by means of a passage on cooling rollers;

F5) a fifth phase for winding the resulting mineralized coating (101, 102, 105, 106).

Optionally three other production phases (F6, F7, F8) can be provided for joining said vapor barrier (107) to the resulting layers (105, 106); therefore, the joining is performed after F4) and before F5) if it occurs in the same production line, or after F5) if it occurs in a different production line.

These phases are:

F6) a sixth phase for preparing the vapor barrier (107) in the form of a film. In particular, there are two cases: in the case of a metal sheet (F6a) it is preferable to unwind a thin aluminum film, instead in the case of a plastic sheet (F6b) it is preferable to directly extrude a smooth polymeric film. Alternatively, it is possible to unwind an equivalent prefabricated polymeric film when the production facility is not equipped with a suitable extruder; however, it is noted that the extruded solution is more advantageous for economical and logistic purposes, and is also more effective for coupling purposes;

F7) a seventh phase for laying a hot glue on said film;

F8) an eight phase for gluing the supporting layer (106) on the opposite side with respect to the mineral layer (105).

Then it is provided to perform said scratched surface (103) on at least one coating

(102):

F9) a ninth phase for superficial mechanical abrasion, which can be performed simultaneously with said mineralized coating and/or afterwards on the finished panel, obtaining scratching effects as described hereinafter.

[0052] This mineralized coating can be advantageously coupled to the foamed panels in thermal insulating material on a dedicated production line by means of a passage in a glue coater, also called glue applicator. The panels coupled with the coating on both sides are then conveyed to a trimmer, so as to obtain a perfect squaring of the manufacture, and then they are sent to a packing station, where the finished panels are progressively stacked on pallets one above the other and then protected with a thermo -retractable or extensible film.

[0053] For the invention purposes, in each panel (10) said scratched surface (103) has to be performed on at least one mineralized coating (102) by means of mechanical abrasion; it is clarified that this is mechanical processing from the outside, which can be made contextually to said completion of the mineralized coating (105, 106, 107) and/or on the finished panel, alternatively or in combination, so as to obtain a greater versatility in the production and/or for diversified and/or combined scratching effects (103) wherein incisions are added in order to achieve a more complex and multiform scratching, or a more effective scratching for adhesion. In the preferred but non-limiting embodiment, in order to reduce the costs and the working times, it (103) is made on the finished panel only which is namely already coupled to the coating.

[0054] More in technical detail of the method and the equipment provided to obtain said scratched surface (103), in the preferred and non-limiting embodiment of the invention, the most outer surface (105) of the coating only (102) or of the finished panel (10) is passed through a station for abrasion including brushes with metallic teeth - thin and rectilinear or bent like a hook- which are mounted on a roller rotating in the opposite direction compared to the direction of the coating or the panel (10, 102, 115). This processing allows to rapidly obtain a scratching (103), which is uniformly distributed on the whole surface with several non-through incisions shaped like scratches, which are rectilinear and parallel to the direction (111, 112, 115) of the machine, like thin striations. Said roller and said brushes are advantageously adjustable so that, by varying the dimension of the single metallic tooth and/or the pitch (116, 117) between two teeth and/or the distance or pressure on the surface and/or the tilt with respect to the plane and/or the orientation on the plane, it is possible to obtain a variable conformation of said scratching (103), according to a desired effect (111 - 117), which can be more effective for the grab of a specific cement mortar for tiles and/or more suitable for the nature and consistency of the surface layer. [0055] It is also possible to obtain the same superficial scratching effect described above (102, 103, 111, 112) by letting the finished and assembled panel, being already joined to the coating (100, 101, 102) and trimmed to size on the four sides, pass through a grinding station, in which there are pushing rollers covered with abrasive paper, preferably having different grain sizes. Likewise the method described above, the superficial effect may vary according to the executive modes; in particular, the depth and the pitch (116, 117) of the striation-like incisions depend on the grain size of the used abrasive paper. For example, said grinding station can be roller calibrating machine for the furnishing industry, where said rollers are adjustable and covered with abrasive paper having a FEPA grain number between P40 and P120; in such a case, said calibrating machine is also equipped with an instantaneous dust suction system, in order to prevent dust from obstructing localized removals and/or micro-scratchings made by the abrasive paper. Also in this second abrasion method, the sanding rollers can be advantageously adjustable so that, by varying the type or grain of the abrasive paper and/or by varying the distance or pressure on the surface and/or the tilt with respect to the plane and/or the orientation on the plane, it is possible to obtain a variable conformation of said scratching (103), according to a desired effect.

[0056] By way of example only, in the figures (Figs. 3a, 3b) are schematically represented two variants of scratching (103a, 103b) which can be obtained with the process and the equipment described above, referred to a superficial widely enlarged portion. In particular, in the first variant (103a) said rectilinear scratches are discontinuous (111, 116) and can be preferably obtained by means of said brushes with thin metallic teeth; additionally, for a combined effect, there are also ellipsoidal (113) and triangular (114) notches which can be obtained with the same device, wherein other brushes have metallic teeth of a different diameter, bent and variously oriented depending on the desired incision, also by tilting the rotation axis if the desired effect requires it. Instead, in the second variant (103b) said rectilinear scratches are continuous (112, 117) and can be preferably obtained by means of said grinding station with pushing rollers coated with abrasive paper; in addition, for a combined effect, ellipsoidal (113) and triangular (114) notches can be obtained as described above. In such a case, it is possible to preliminarily make the notches on the coating, and then to make the striation in the form of continuous scratches on the already assembled panel. It has been experimentally found that the different scratching effects (103, 111 - 117) described above can be easily and rapidly obtained by means of the described equipment, with said brushes or abrasive paper, providing the manufacturer with industrial advantages and/or advantages in terms of results on the finished product.

[0057] In a further different embodiment not represented in the figures, suitable for increasing the resistance of the panel (10) to high temperatures and/or fire, the glue layer (104) comprises expanding graphite and/or sodium silicate and/or ammonium polyphosphate and/or triethyl phosphate called by the acronym TEP and/or zinc borate, said components being considered individually or in combination with each other in a global concentration of between 1% and 20% on the total weight. And also, alternatively or in addition to this solution, in order to obtain a greater increase, said central layer (100) is expected to be made of a polymer comprising expanding graphite and/or sodium silicate and/or trichloro propyl phosphate called by the acronym TCPP and/or ammonium polyphosphate and/or brominated compounds, said components being considered individually or in combination with each other in a global concentration of between 1% and 20% on the total weight. It is noted that such an increase of fire resistance can be industrially obtained in an easy way and with a limited cost increase, only by adding the above-mentioned ingredients to the composition of said insulating material (100) and/or glue (104), without additional layers or particular processing. [0058] Moreover, it has been found that in practical use the insulating and protective panel (10) proposed in the present invention is contextually provided with a high resistance to bending, damp and fire, it is very lightweight self- supporting and easy to transport, and it can be processed in the construction site like any non-conductive panel, safely and without releasing dusts. Its outer surface (103, 105) contextually protects from water and from open flames, and also offers a good grab to effectively support the laying of tiles or plasters, without adding any interposed film, fabric, net or primer for ensuring the grab.

[0059] Finally, it has been experimentally found that said superficial scratching (103), which is mechanically performed as provided by the present invention, allows said insulating and protective panel (10) to increase the adhesion, considerably improving the values obtained in a test of tensile strength perpendicular to the plane for cement adhesives, also called resistance to tearing or pull-out, (101, 102, 105); said test has been performed on a packet including the proposed panel (10) in the different variants (Fig. 4a, 4b) as described above, and with one ceramic tile (202, 203) glued by means of a common cement mortar, obtaining values always higher than 0.2 N/mm ² according to the EN 1348 regulation. Moreover, it has been instrumentally verified that the insulating and protective panel (10) described above, in the advantageous variant provided with vapor barrier (107) in aluminum or in plastic (Fig. 4b) is waterproof and also gas- tight, with a water vapor permeability degree or perm rating which is smaller than 0.1 according to the ASTM regulation E96 method E.

Nomenclature

(10) rigid panel for construction, according to the present invention;

(100) central layer in a foamed insulating material, such as extruded and expanded polystyrene or extruded polystyrene called by the acronym XPS, or expanded polyurethane called by the acronym EPS, or expanded polyurethane;

(101, 102) mineralized coating, placed on the external part of the panel in a symmetrical way with respect to the central layer, respectively on the back side or structure-side (101) and on the front side or finishing-side (102), wherein at least the coating on the finishing-side has the outer surface scratched according to the present invention;

(102a) mineralized coating in the minimum basic stratification;

(102b) mineralized coating in the variant with vapor barrier;

(103) outer surface scratched;

(103a, 103b) different effects of superficial scratching;

(104) glue layer for the foamed central layer;

(105) mineral layer as external finishing;

(106) supporting layer, acting as reinforcement for the mineral layer, which is impregnated and saturated with a thin impregnating adhesive layer acting as binder for the mineral aggregates;

(107) vapor barrier possibly provided for increasing the resistance to the passage of gases and the impermeability of the panel;

(108) glue for the vapor barrier; (109) back side or structure-side for example facing a masonry;

(110) front side or finishing-side, which can be coated with a layer of tiles.

(111) rectilinear and non-continuous scratch, like a non-through incision parallel to the other discontinuous scratches; (112) rectilinear and continuous scratch, like a non-through incision parallel to the other continuous scratches;

(113) ellipsoidal notch, like a non-through incision with ellipsoidal or circular notch;

(114) triangular notch, like a non-through incision with triangular notch; (115) direction of the parallel scratches;

(116) center distance between parallel and discontinuous scratches;

(117) center distance between parallel and continuous scratches;

(201) load-bearing structure, for example a masonry or a floor slab, or a partition in plasterboard or wood; (202) tile, in a ceramic material with thin thickness or equivalent;

(203) adhesive layer for laying, in a glue or a cement mortar for tiles;

(204) finishing grout line between tiles.