BR112014028794B1 - CONSTRUCTION ELEMENT FOR WALLS AND WALL COVERINGS, AND METHOD OF MANUFACTURING SUCH ELEMENT - Google Patents

Abstract

building element for walls and wall coverings, and methods of manufacturing said element. A building element for walls and wall coverings is described, comprising at least one layer of covering material (11) and a layer of natural light lime (12) bonded to the covering material (11) so as to form, after drying, a single body.

Description

FIELD OF THE INVENTION

[001] The present invention relates to a building element for walls and wall cladding, and a method of manufacturing the same element. Patent document DE 10160665 represents an example of a building element, the characteristics of which are described in the preamble of claim 1.

BACKGROUND OF THE INVENTION

[002] Natural lime is known as a natural hydraulic lime mortar. It is obtained by cooking marly limestone in vertical ovens at a temperature of about 1000 °C. A long quenching and maturation is carried out before crushing. For application, just mix the lime powder with water, until a smooth, smooth and lump-free paste is obtained.

[003] Natural lime has been abandoned in recent years in favor of new materials that are easier to apply and are more durable, such as those obtained by plasticizer components. Recently, however, natural lime is being re-evaluated for a number of reasons.

[004] First, as indicated by its name, natural lime is a natural product that has been known since antiquity, in which a certain reliance is placed in terms of non-toxicity.

[005] Secondly, it is breathable, thus preventing the accumulation of moisture that can make environments unhealthy.

[006] Another reason why lime is more often used is linked to its fire resistance. In fact, it has a class 1 fire resistance, meaning it is ranked among the least combustible materials.

[007] Furthermore, natural lime has a very low thermal conductivity of about 0.54 W/mK. Above all, because of this last property, lime is being used more and more to produce thermal coatings, that is, external coatings for dwellings, in order to reduce the conductivity of the coated walls. For this purpose it is often mixed with aggregates having insulating properties such as granulated cork, natural or artificial fibers such as polystyrene and the like. Because of these mixtures, lime so composed is often referred to as "light" because these aggregates generally have a lower specific gravity than lime.

[008] The use of light lime is, however, laborious, as it requires at least 24 hours of drying under optimal conditions, and provided that the thickness of each spreading layer does not exceed 2 cm. Drying times can increase further during the winter period.

[009] Furthermore, when layers of more than 2 cm are applied at a time, unpleasant depressions and bumps often form in vertical walls.

[010] An insulated outer cladding, for example, may require the placement of up to 8 cm of natural lime. This means that at least four layers will have to be made.

[011] It should also be considered that natural lime does not have a great mechanical strength, and thus the placement of at least one mesh must be provided in order to avoid the formation of peeling and cracking. Furthermore, the effect of wind and bad weather, in general, tends to degrade the most superficial layers of lime very quickly.

SUMMARY OF THE INVENTION

[012] The objective of the present invention is to provide a construction element for walls and wall coverings, which allows the advantages of natural lime to be obtained while its defects are minimized, including the difficult application work and its low mechanical strength.

[013] The purpose of the present invention is to obtain a building element for walls and wall coverings, according to claim 1.

[014] Another objective of the present invention is to obtain a "sandwich" type partition wall element, substantially obtained by the construction element described above with the addition of another coating layer on the free face of the natural light lime layer.

[015] Another objective of the present invention is to present a method of manufacturing said coating element, allowing said element to be obtained very quickly, with uniform characteristics in terms of shape and finish.

[016] Another objective of this invention is to present a method of manufacturing a cladding element for walls according to claim 9.

[017] The dependent claims describe preferred embodiments of the invention, forming an integral part of this description.

BRIEF DESCRIPTION OF THE DRAWINGS

[018] Other features and advantages of the invention will become more evident in light of the detailed description of preferred, but not exclusive, embodiments of a wall cladding element, illustrated by means of a non-limiting example, with the help of the accompanying drawings , in which:- fig. 1 is a cross-sectional view according to the thickness of a building element of the present invention; FIG. 2 represents a variant of the building element according to the same view as in figure 1; - figure 3 shows another variant of the building element according to the same view as in figure 1 ; of construction according to the same view as in figure 1.

[019] The same reference numbers and letters in the drawings identify like elements or components.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[020] According to the present invention, and observing fig. 1, a cladding element 1 comprises a first layer 11 of cladding material, intended to remain visible, and at least one second layer 12 of light lime.

[021] According to a first embodiment of the invention, said first layer is made with the so-called fine stone. Thin stone is made up of a very thin slice of hard stone supported by a layer of resin, where the term “very thin” means approximately tenths of a millimeter to a few millimeters.

[022] This layer of fine stone is obtained by gluing a layer of resin, possibly supported by a fiberglass mesh, on a supporting surface of natural stone, such as sandstone, lava stone, quartzite, etc.. After the resin is dry, a thin layer of stone is literally stripped from said surface, thanks to the mesh attached to that layer. The fine stone slab thus obtained does not have a perfectly smooth surface, but rather has a natural roughness due to its removal from the other layers of the aforementioned support surface.

[023] The use of fine stone has been known for some time, but it has always been associated with support structures defined by aluminum panels that are typically hollow inside, with hexagonal structure cavities.

[024] Dry lime is able to provide the necessary support for the coating layer. In particular, according to the present invention, the fixation of the lime to the coating layer preferably takes place thanks to the adhesion capacity of the lime itself. Thus, when dry, the lime is naturally attached to the coating layer.

[025] According to the present invention, the fine stone is supported by a layer of natural light lime, with a variable thickness between 1, 10, 20, 30, 40 cm or more as required.

[026] Below, the term lime or natural lime indicates light natural lime.

[027] Regarding the thickness of the lime layer, one or more retention meshes 13 can be introduced in the lime itself, as seen in figure 2. Meshes 13 are already well known. They can be made of plastic or fiberglass.

[028] According to a preferred manufacturing process, the thin stone layer is placed on a support surface, usually horizontal, and the natural lime is placed over it, with the possible introduction of the retaining mesh 13.

[029] A fine stone slab therefore has a natural stone face and a resin coated face.

[030] The use of suitable fixatives, before the settlement of lime, can be provided in relation to the roughness of the surface of the face coated with resin. Preferred fasteners can be made, for example, from polyurethane, or from epoxy resins, possibly bicomponent.

[031] Once the lime has been settled, it can be naturally air-dried, or kiln-dried. According to the present invention, a slab is obtained which can then be cut to specific requirements, forming bricks or slabs, depending on the final size ratios.

[032] Contrary to popular belief, thin stone slabs can have a certain degree of flexibility, and the construction elements that can be obtained can present a discrete curvature of the visible part, which can be concave or convex.

[033] According to a second variant of the present invention, said first layer is made of tufa, that is, a natural limestone.

[034] Tufa is a particularly brittle material, but it has excellent properties related to its thermal insulation and heat storage capabilities.

[035] This material is used in large quantities, however, due to its fragility, it is extracted from larger blocks and cut into thick blocks, with a thickness not less than 5 to 7 cm.

[036] To cover a wall with tufa, therefore, it is necessary to use a considerable amount of material, due to the difficulty of handling. This implies obvious extraction, cutting and transport costs as well as placement costs. According to the present invention, said first layer 11 of the building element can be made of tuft. The lime layer 12 provides for the fabrication of a support that is hard enough to prevent the tuft from being crushed during placement and during handling of the construction element obtained.

[037] According to a preferred variant of the invention, the tuft layer can be reduced to a few millimeters. Possible thicknesses range from 3 to 4 mm up to 20 mm or more.

[038] According to a preferred manufacturing method, a tufa slab having a thickness S is first cut and placed on a support surface.

[039] Natural lime is placed on the tufa layer according to the methods previously illustrated, thus obtaining an intermediate product 1 that coincides with that illustrated in figures 1 or 2.

[040] After the natural lime layer has dried, the obtained element is turned over, leaving the lime layer 12 as a support element. Another layer of lime 12' is then placed over the tufa layer 11. An intermediate product 1b is obtained, as shown in figure 3.

[041] After this second layer of natural lime 12' has dried, the element obtained is cut perpendicularly, in the thickness S of the element, in the middle part r of the tufa layer 11. Thus, two elements of building material 1 are obtained, with a thickness equal to S / 2.

[042] According to another variant of the present invention, another tuft layer 11' can be coupled to the free face of the lime layer 12, preferably until the lime layer has solidified, so as to form a single body. , as seen in figure 4. In fact, it should be noted that the obtained element forms a kind of sandwich, with the light lime 12 between the two tufa layers. This variant is particularly suitable for the manufacture of partitions and partition walls in general.

[043] According to the present invention a multiple "sandwich" comprises several layers of lime alternating with layers of tufa.

[044] According to a preferred manufacturing method of dividing wall elements, a multiple "sandwich" is previously fabricated and then cut perpendicularly, in the thickness S of the "sandwich", in the middle part r of each tufa layer, such as shown in figure 3. A number of partition wall elements can thus be obtained at the same time. It is preferable that this “sandwich” is transported by a conveyor belt so that the cut is made horizontally, parallel to the direction of movement of the conveyor belt. The support provided by the lime itself allows tufa coating layers having a thickness of less than 2 centimeters to be obtained, as provided in the prior art.

[045] A preferred multiple “sandwich” manufacturing method may provide for the overlap of the upper layers after the lower lime layers are partially dry.

[046] The openings for the passage of the water pipe and electrical wiring conduits can already be made during the manufacturing step of the building elements or dividing wall, according to the present invention.

[047] The water and electrical wiring conduits can actually be embedded in the lime layer, which greatly simplifies the successive manufacturing steps. These solutions, for example, cannot be achieved through the exclusive use of aluminum panels of hexagonal structure as support, because there would be no filling material to embed the ducts.

[048] On the other hand, by combining a cladding layer 11 with aluminum support panels of hexagonal structure and light lime, suitable tiles for the creation of floors and floor surfaces can also be obtained. In this case, the pre-insertion of the water pipes in the lime layer allows underfloor heating systems to be produced.

[049] The tufa coated element variant is particularly advantageous due to the tufa's properties, especially when breakable, as the element is easily manipulated to obtain suitable shapes in situ, without the use of special tools. Thus, thanks to the present invention, the excessive brittleness of this material has therefore been converted into strength.

[050] Advantageously, thanks to the present invention: - The construction elements coated with tufa are laid to form more or less continuous walls; - Coatings and finishes can be obtained on these walls; - Resins, paints or water repellents can be placed on the tufa layer, in order to reinforce it; these resins and paints are already well known.

[051] According to the present invention, the placement of the obtained element can be advantageously performed with additional lime, thus obtaining a composition of the "lime on lime" type, without the use of adhesives or additional mechanical components that can compromise the heat bridges.

[052] Limestone has a surface roughness that also allows to avoid any fixation between limestone and limestone.

[053] After placement, the cladding material layer 11, be it fine stone instead of tufa, ceramic or terracotta tiles, is visible.

[054] Advantageously, according to the present invention, natural lime is applied when it is already in a solid state, thus limiting the curing times resulting from the problem of drying the various layers of lime. Furthermore, the use of already solidified lime allows the handling of breakable materials, such as fine stone or fine natural tufa tiles, which could not be handled without a support.

[055] Furthermore, with light lime having a lower specific weight than tufa, the building element obtained according to the present invention is lighter than a traditional tufa block with the same dimensions. Furthermore, it has better thermal insulation properties than plain tufa.

[056] Another advantage provided by the present invention is that, in addition to having excellent physical and mechanical properties, natural lime is much more economical in terms of the objective cost of the material and in terms of transportation, because it is normally transported in bags.

[057] Hexagonally structured aluminum panels, which in themselves are already expensive, have a disadvantageous weight/volume ratio, thus significantly affecting transport costs.

[058] It is also possible to use aluminum panels of hexagonal structure to contribute to the building element described here, reinforcing it, when the building elements to be manufactured are of considerable size, such as entire walls or considerable parts of the same. According to a preferred variant of the invention, one or more retaining nets 13 can be replaced by aluminum panels of hexagonal structure.

[059] In this case, these hexagonally structured aluminum panels can be interposed between layer 11 and lime layer 12, or within the thickness of lime layer 12.

[060] According to another aspect of the invention, the combination of light lime and tufa allows an advantageous mixture of thermodynamic characteristics, both in terms of thermal insulation and thermal capacity, to be obtained. Furthermore, a considerable increase in acoustic insulation was observed, due to the strong physical and mechanical heterogeneity of the two materials.

[061] According to another preferred embodiment of the invention, a building module formed by two elements can be obtained, so that the lime is internally confined and only the respective coating layers are externally visible.

[062] This solution is ideal above all in the manufacture of single block removable walls and street sidings.

[063] The elements and features illustrated in the different preferred embodiments can be combined with each other, without however departing from the scope of protection of the present application.

Claims (11)

1. Building element for walls and wall cladding, comprising at least one layer of cladding material (11) and a lightweight inner layer bonded to the cladding material (11) so as to form, by drying, a single body , characterized in that said inner layer is made of natural light lime (12). 2. Building element according to claim 1, characterized in that said layer of cladding material (11) comprises a thin sandstone plate having a thickness between tenths of a millimeter and a few millimeters. 3. Building element according to claim 2, characterized in that the thin plate is obtained by tearing off said plate from a surface. 4. Building element according to claim 1, characterized in that said coating material is tufa (limestone), with a thickness greater than 3 to 4 mm. 5. Building element according to claim 1, characterized in that said cladding material is a ceramic brick or similar. 6. Building element, according to any one of the preceding claims, characterized in that a fastener is interposed between said coating layer (11) and said layer of natural light lime (12). 7. Building element according to any one of the preceding claims, characterized in that said layer of natural light lime (12) has a thickness greater than 1 cm. 8. Building element for walls and wall cladding, characterized in that it comprises a dividing wall element including a first cladding material layer (11) and a second cladding material layer (11') with at least a layer of natural light lime (12) interposed and dried to form a “sandwich”. 9. Method of manufacturing a building element for walls and wall cladding, characterized in that it comprises at least the following steps: - Preparing a cladding layer (11); - Placing said cladding layer (11) on a horizontal plane; - Spread a layer of light natural lime (12); - Dry said layer of light natural lime (12). 10. Method of manufacturing a building element, according to claim 9, characterized in that it further comprises a step of interposing at least one reinforcing mesh (13) of the thickness of the lime layer (12), and / or preparing a fixative in the coating layer (11), before the lime layer (12) is spread. 11. Method of manufacturing a building element, according to claims 9 or 10, characterized in that it further comprises the following steps, after drying: - Flip the obtained element; - Spread an additional layer of natural light lime ( 12'); - Drying said additional layer of natural light lime (12'); - Cut the element obtained perpendicularly to the thickness (S) of the element, in a respective middle part (r) of the coating layer (11).

Images