Insulating panel for construction with grab surface

Abstract

An insulating panel for use in construction has a central layer, a first water-resistant coating and a second water-resistant coating on opposite sides of the central layer. The first coating and the second coating are joined to the central layer with a glue layer or a thermo-adhesive material. Each of first coating and the second coating is a plastic sheet that is scratched or abraded.

Claims

1. An insulating panel for use in construction, the insulating panel comprising: a central layer formed of an insulating foam and water-resistant material having a low specific weight and high dimensional stability, said central layer having a front side and a back side; a first water-resistant coating joined to the front side of said central layer; and a second water-resistant coating joined to the back side of said central layer, each of said first water-resistant coating and said second water-resistant coating being adhered by a glue layer or a thermo-adhesive material to the respective front side and the back side of said central layer, wherein each of said first water-resistant coating and said second water-resistant coating is a plastic sheet having a thickness of 0.2 millimeters with a tolerance of 0.1 millimeters and a density of 1.1 kilograms per cubic decimeter with a tolerance of 0.2 kilograms per cubic decimeter and a hardness of D75 with a tolerance of 20, wherein said first water-resistant coating has an exterior surface that is scratched such that the insulating panel has a tear resistance of no less than 0.5 Newtons per square millimeter.

2. The insulating panel of claim 1, further comprising: a nonwoven fabric layer interposed between the plastic sheet and said central layer and joined to said central layer by the glue layer.

3. The insulating panel of claim 2, wherein said nonwoven fabric layer is treated so as to be alkaline resistant, said nonwoven fabric layer being of a material selected from the group consisting of polypropylene, polyamide and polyester.

4. The insulating panel of claim 2, wherein the glue layer is selected from the group consisting of a two-component polyurethane adhesive and an epoxy glue.

5. The insulating panel of claim 4, wherein the glue layer has a component selected from the group consisting of an expandable graphite, a sodium silicate, an ammonium polyphosphate, a triethyl phosphate, a zinc borate and mixtures thereof, the component having concentration of between 1% and 20% of a total weight of the glue layer.

6. The insulating panel of claim 4, wherein the glue layer has a net of fiberglass therein, the net having a mesh opening of a minimum of 5 millimeters by 5 millimeters and a maximum of 20 millimeters by 20 millimeters.

7. The insulating panel of claim 1, further comprising: a multi-layer coating coupling the plastic sheet to said central layer, wherein layers of said multi-layer coating are coupled to each other by the thermo-adhesive material or by glue layer.

8. The insulating panel of claim 7, wherein the multi-layer coating is pre-coupled.

9. The insulating panel of claim 1, wherein the plastic sheet is of a material selected from the group consisting of high-density polyethylene, polypropylene, high-impact polystyrene and mixtures thereof.

10. The insulating panel of claim 1, wherein the scratch on the exterior surface of said first water-resistant coating is mechanically abraded into incisions uniformly distributed over an entirety of the exterior surface of said first water-resistant coating, each of the incisions having a depth less than a thickness of said first water-resistant coating.

11. The insulating panel of claim 1, wherein said central layer has a constant thickness of between 4 millimeters and 200 millimeters and has a density of between 15 kilograms per cubic meter and 50 kilograms per cubic meter.

12. The insulating panel of claim 1, wherein said central layer has a constant thickness of between 6 millimeters and 50 millimeters and has a density of 30 kilograms per cubic meter with a tolerance of 10 kilograms per cubic meter.

13. The insulating panel of claim 1, wherein said central layer is formed of a polymer selected from the group consisting of an expandable graphite, a sodium silicate, a trichloro propyl phosphate, and a brominated compound.

14. The insulating panel of claim 1, wherein the plastic sheet is formed of a polymer selected from the group consisting of an expanding graphite, a sodium silicate, a trichloro propyl phosphate, an ammonium polyphosphate, a brominated polymer and mixtures thereof.

15. A process for forming an insulating panel, the process comprising: making a foamed sheet as a central layer of the insulating panel; curing the foamed sheet into a plurality of thinner sheets; preparing a coating; abrading the coating by mechanically cutting an outer surface of the coating so as to scratch the coating with uniformly distributed non-through incisions; joining the abraded coating onto the foamed sheet with a glue layer interposed between the abraded coating and the foamed sheet or with a thermal adhesive, the coating being symmetrically applied to opposite sides of the foamed sheet; cutting the foamed sheet with the coating to a desired size into finished panels; and packing and moving the finished panels for transport, wherein the step of abrading is carried out by sanding or brushing.

16. The process of claim 15, wherein the abrading is carried out by brushing with at least one flat passage on a roller conveyor, the roller conveyor having at least one roll having metallic brushes with thin wires having folded ends, the at least one roller being height adjustable or tiltable.

17. The process of claim 15, wherein the abrading is by sanding by at least one flat passage through a grinding station, the grinding station having pushing rollers covered with an abrasive paper, the pushing rollers being height adjustable or tiltable.

18. The process of claim 15, wherein the grinding station has a calibrating machine with adjustable roller, the adjustable roller being covered with the abrasive paper having a FEPA grain number of between P40 and P120, the calibrating machine having a dust suction system therein.

Description

CONTENT OF THE DRAWINGS

(1) FIG. 1 represents the insulating 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.

(2) FIG. 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.

(3) FIGS. 3a and 3b schematically represent the superficial scratching of the 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 scratches 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.

(4) FIGS. 4a, 4b, and 4c are enlargements of the sectioned coating, according to the dashed rectangle in FIG. 1 (IV), related to three variants (IVa, IVb, IVc).

PRACTICAL REALIZATION OF THE SUBJECT MATTER OF THE INVENTION

(5) Also with reference to the figures (FIGS. 1-4), an insulating panel for construction (10) is proposed of the insulating and 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 vapor and damp. In particular, the present invention proposes an advantageous multi-layer panel which is suitable for installations in damp environments such as bathrooms or saunas, which has at least one surface layer provided with a particular scratching which considerably increases said tensile resistance perpendicularly to the plane, also called resistance to tearing or pull-out: this scratching is obtained with a superficial mechanical treatment which is inexpensive, and easy to be industrially obtained, making the laying of ceramic tiles directly glued thereon more effective, safer and more durable, according to the aims described above.

(6) It is noted that the proposed insulating 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 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 such 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.

(7) The proposed insulating panel (10) is made up of a central layer (100) in an foamed and damp-resistant insulating material, which has a low specific weight and a high dimensional stability, such as XPS or EPS polystyrene or expanded polyurethane, and of a damp-resistant coating (101, 102) 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, hardens and increases the resistance to the passage of vapor and/or the impermeability of the panel (10). The coating (101, 102) can be in a single layer, made of one material only, or multi-layer made of different materials as described hereinafter. When the coating is multi-layer, the single layers can be coupled by means of thermo-adhesion or gluing for example with a two-component polyurethane glue. Said coating (101, 102) can be thermo-adhered or glued to said central layer (100), for example by means of a glue layer (104), in a two-component polyurethane adhesive or an epoxy glue.

(8) Said central layer (100) has a constant thickness between 4 mm and 200 mm, with a density ranging between about 15 and 50 kg/m.sup.3, each coating (101, 102), has instead a constant thickness greater than 0.1 mm; in the preferred embodiment it is provided that said central layer has a constant thickness between 6 mm and 50 mm and a density of about 30 kg/m.sup.3 with a tolerance of +/10 kg/m.sup.3, while each coating has a thickness equal to 0.2 mm with a tolerance of +/1 mm. A finished insulating panel (10) (FIGS. 1, 2) has, therefore, an overall thickness between about 6.2 and 52 mm; greater or lower values are however suitable for the proposed panel depending on a specific application.

(9) The coating provided by the invention (101, 102, 102a, 102b) has a high resistance to the passage of vapor and a high density: in particular, at least one coating (102) has the outer surface scratched (103) namely provided with various non-through incisions, also called scratchings, which are shaped like scratches and/or grooves and/or striations and/or notches or small-sized 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 0.5 N/mm.sup.2 according to said EN 1348 regulation, ensuring a high reliability also in vertical installations and in damp environments. In particular, as a clarification, this resistance value, also cited in the claims, is typical of an insulating panel (10) made such as provided by the present invention (100, 101, 102, 102a-102c, 103) and it is intended to be referred to the expressly indicated regulation and to the measuring method above described.

(10) 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 to 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).

(11) More in technical detail, the coating (101, 102, 102a, 102c) (FIG. 4a, 4b) consists of a plastic plate (105) of a thickness equal to 0.2 mm with a tolerance of +/0.1 mm, a density equal to 1.1 kg/dm.sup.3 with a tolerance of +/0.2 kg/dm, and a Rockwell hardness D equal to 75 with a tolerance of +/20. This plate has the combined function of increasing the resistance to the passage of vapor and the panel impermeability, protecting from impacts, and acting as structural reinforcement, and also allowing a suitable making of said scratched surface (103), with non-through and well controlled incisions. It is made of a plastic material of the virgin or recycled polyolefin type, or in polyester or polystyrene, both in the generic version and in version with high resistance to impact: for example, the material called by the acronym HDPE, or PP, or also GPPS or HIPS or mixtures thereof is suitable. In a preferred embodiment (102a, FIG. 4a), said plastic plate (105) is joined to the central layer (100) by means of a glue layer (104); alternatively (102b), where the material compatibility allows it, it (105) is joined by means of thermo-adhesion (FIG. 4b).

(12) In a different embodiment (FIG. 4c) intended to facilitate the adhesion of said plastic plate (105) to the central layer (100), it is provided to interpose between them a permeable layer of a non-woven fabric (106) or called by the acronym TNT, made of a plastic material alternatively selected among: polypropylene, polyamide, or polyester. Said TNT is coupled to the plastic plate like a multi-layer coating (102c, 105, 106), such as for example pre-coupled, being joined to each other by thermo-adhesion or gluing: afterwards, said multi-layer coating is joined (101, 102) to the central layer (100) with a glue layer (104). Preferentially, said non-woven fabric (106) undergoes a treatment for resisting in alkaline environments, such as to increase the safety and the global duration of an installation.

(13) The insulating panel for construction (10, 103) described above is suitable for the continuous industrial production with high production volumes, according to a productive process comprising the following operative phases (F1-F9): F1) a first phase for making a foamed plate suitable for forming said central layer (100) of the panel, alternatively obtained by means of extrusion and expansion if it is made of XPS polystyrene, or obtained by means of expansion if it is made of EPS polystyrene or polyurethane; F2) a second phase for curing said foamed plate; F3) a third phase for cutting in thinner plates, according to the needs; F4) a fourth phase for preparing the coating (101, 102), with possible pre-coupling of multiple layers where it is a multi-layer coating; F5) a fifth abrasion phase, by brushing or sanding, simultaneous with the previous phase (F4), where the outer surface of at least one coating (102) is mechanically machined so as to make it scratched (103), with various non-through incisions which are uniformly distributed; F6) a sixth phase for joining said coating (101, 102) on said foamed plate (100), alternatively by means of an interposed glue layer (104) or by means of thermo-adhesion, wherein the coating is symmetrically applied on both sides of the plate like a sandwich panel; F7) a seventh finishing phase, where said plate with coating is cut to size in finished panels by means of a cutting and squaring device at 90, such as for example a pantograph; F8) an eighth abrasion phase, by brushing or sanding, simultaneous with the previous phase (F7), where the outer surface of at least one coating (102) is mechanically machined so as to make it scratched (103), with various non-through incisions which are uniformly distributed; F9) a ninth phase for packing and moving said grouped panels, being for example packed in pallets for the transport to the client.

(14) In particular, said fifth phase (F5) and said eighth phase (F8) can be alternatively performed, namely only one of said phases, or both; as a clarification, for the aims of the invention, at least one of them must be however performed on the outer surface of at least one coating (102) so as to always provide the panel (10) with a scratched surface (103) which improves the adhesion and the grab of the cement mortar.

(15) 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, simultaneously to said phase for preparation of the coating (102, F4) its most outer surface is passed through a station for abrasion (F5) including brushes with metallic teeththin and rectilinear or bent like a hookwhich are mounted on a roller rotating in the opposite direction compared to the direction of the coating (102, 115). This working allows to rapidly perform 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, similar to 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.

(16) As a clarification, the abrasion provided by the invention is a mechanical machining from the outside which can be performed in two different phases of the productive process, so as to obtain a greater production versatility and/or combined and/or varied scratching effects (103). Indeed, the abrasion can be performed simultaneously to the phase for making the coating (102, F4-F5) with the operations and the equipment described above, or it could be subsequently performed (F8), on the finished panel: alternatively, it is performed in both phases (F5 and F8), so as to sum the effects in order to achieve a more complex and multiform and/or more effective scratching for adhesion.

(17) It is indeed 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. Also in this case, 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 a roller calibrating machine for the furnishing industry, where said rollers are adjustable and are 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 effect (103), according to a desired effect.

(18) By way of example only, the figures (FIGS. 3a, 3b) schematically represent 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 where 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. In the second variant (103b), instead, said rectilinear scratches are continuous (112, 117) and can be preferably obtained by means of said grinding station with pushing rollers coated with abrasive papers: in addition, for a combined effect, also ellipsoidal (113) and triangular (114) notches can be obtained as described above. In such case it is thus preferable 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 obtained in both dedicated productive phases (F5, F8) by means of the described equipment, with said brushes or with abrasive paper, providing the manufacturer with industrial advantages and/or advantages in terms of results of the finished product.

(19) 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 between 1% and 20% on the total weight. Alternatively, or in addition to this solution, in order to further increase the resistance to fire and avoid the collapsing in case of fire, it is provided to add a small net of fiberglass acting as reinforcement in said glue layer (104). To this aim, a small net with a mesh opening between a minimum of 5 mm by 5 mm and a maximum of 20 mm by 20 mm is suitable. And still, alternatively or additionally to these solutions, in order to obtain a greater increase, said central layer (100) and/or said plastic plate (105) is expected to be made in a polymer also 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 between 1% and 20% on the total weight of said layer (100) for increasing the fire resistance of the panel (10). It is noted that such an increase of the 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 (100) and/or adhesive (104) and/or plastic (105) material, without any particular processing.

(20) Moreover, it has been found that in practical use the insulating panel (10) proposed in the present invention is contextually provided with a high resistance to bending and damp, it is very lightweight, self-supporting and easy to transport, and it can be processed in the construction site like any panel for non-conduction, safely and without releasing dusts. In particular, the outer scratched surface (103) ensures an improved adhesion in order to more effectively support the laying of tiles or plasters, compared to similar multi-layer solutions without cement, by using common glues or cement mortars for tiles and without adding any interposed film, fabric, net or primer to allow the grab.

(21) Finally, it has been experimentally found that said superficial scratching (103), mechanically made as provided by the present invention, allows the proposed insulating panel (10) to obtain improved values in a test of tensile strength perpendicular to the plane, also called resistance to tearing or pull-out; said test has been performed on a packet including the proposed panel (10) in the different variants as described above, and one ceramic tile (202, 203) glued by means of a common cement mortar, obtaining values always higher than 0.5 n/mmq according to said EN 1348 regulation. In particular, on said packet subjected to traction, the breaking interface is in the central layer (100) namely inside the foamed insulating material; this occurs due to the fact that all the adhesion interfaces of the panel between the layers and on the surface of grab are so effective and resistant that the weak spot of the stratification corresponds to the foam material having a lower density and a structure of cellular type.

NOMENCLATURE

(22) (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) external coating, respectively placed on the back side or structure-side (101) and on the front side or finishing-side (102), wherein at least the coating on said finishing-side has the outer surface scratched according to the present invention; (102a-102c) different embodiments of the coating; (103) outer scratched surface; (103a, 103b) alternative effects of superficial scratching; (104) glue layer, for example a two-component polyurethane adhesive; (105) plastic plate; (106) non-woven fabric; (107) mineral layer; (108) supporting layer of the mineral layer or carrier; (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) discontinuous and rectilinear scratching, like a non-through incision parallel to the other discontinuous scratchings; (112) continuous and rectilinear scratching, like a non-through incision parallel to the other continuous scratchings; (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.