EP4640967A1

EP4640967A1 - Vacuum panel structure for thermal insulation

Info

Publication number: EP4640967A1
Application number: EP25172077.7A
Authority: EP
Inventors: Marco Conte
Original assignee: ComFall Srls
Current assignee: ComFall Srls
Priority date: 2024-04-24
Filing date: 2025-04-23
Publication date: 2025-10-29

Abstract

The present invention relates to a panel structure (100) for thermal insulation, comprising:
- a vacuum panel (1), for thermal insulation, having a first face (11) and a second face (12) opposite the first face (11);
- a first covering panel (2) being dimensioned and arranged so as to cover completely the first face (11);
- a second covering panel (3) being dimensioned and arranged so as to cover completely the second face (12);
- retaining means (4) configured to secure together the first covering panel (2) and the second covering panel (3) and to retain the vacuum panel (1) between them.

Description

Technical sector

The present invention relates to a vacuum panel structure for thermal insulation. In particular, the present invention relates to a vacuum panel structure for thermal insulation which can be used, in particular, for the thermal insulation of buildings. Also, the vacuum panel structure for thermal insulation can be used in the refrigeration sector.

Background

Nowadays heat-insulating panels with a particularly small thickness, used in particular in the building sector, are known.
Among the small-thickness heat insulating panels, panels known as "vacuum panels or "vacuum insulated panels" (VIP) are particularly widespread and favourably regarded. Vacuum panels are products which usually comprise a core of powder or fibres, typically mineral based, which is pressed and placed under a vacuum inside a suitable casing or film.
The casing or film is substantially gas and vapour impermeable. In this way, the casing or film prevents the entry of air and moisture into the core enclosed inside it.
Moreover, since the core is "under a vacuum", namely it is kept at particularly low pressures, it is possible to reduce greatly the mobility of the few remaining air particles which are trapped inside the casing. Consequently, the thermal conductivity of the panel is particularly low, reaching values even lower than 0.002 W/mK.
The main advantage associated with the use of vacuum panels is the small thickness, where the minimum size of the assembled unit is about 3 cm.
In vacuum panels, the protective casing consists mainly of a film or an aluminium plate, which however is very delicate and prone to tear.
If said casing is perforated or torn, the thermal performance of the panel decreases drastically, by even more than ten times compared to the performance of an undamaged panel.
Nowadays vacuum panels may be generally divided up into two main types:

vacuum panels with a core consisting of pyrogenic silica, also known as "fumed silica";
vacuum panels with a glass fibre core.

Typically, the core, whether it consists of fumed silica or glass fibre, also comprises a "getter", namely a material able to absorb moisture and, for this reason, able to increase the duration over time of the vacuum seal.
Vacuum panels with a glass fibre core, in general, comprise a casing or sheathing made of fabric consisting of glass fibre and aluminium, which makes them more resistant to cutting and erosion compared to other types of vacuum panels which are currently known.
The casing may also be made using, in addition to aluminium, also other materials including polyethylene (PE), polyethylene terephthalate (PET), vacuum metallized polyurethane terephthalate (VMPET), in addition to aluminium, or instead of aluminium, or in combination with each other and/or with aluminium.
The overall thickness of the casing is variable, since the thickness of the single materials which form it may vary.
The vacuum panels with a glass fibre core manage to reach thermal conductivity values (typically of between 0.0013 and 0.003 W/mK) which are lower than those of fumed silica panels (typically between 0.004 and 0.0035 W/mK).
Moreover, compared to vacuum panels with a fumed silica core, vacuum panels with a glass fibre core have lower production costs.
Vacuum panels are mainly used in the sector of refrigeration, for example for refrigerators.
Increasingly more frequently, the vacuum panels of the prior art are also used for the insulation of roofing, flooring and on walls, mainly by means of dry laying (i.e., behind plasterboard panels) since a reinforced skim finish may not be applied on them.
In fact, the reinforced skim finish could easily damage the surface layer, namely the casing, of the panel, which would therefore lose most of its thermal insulation performance features.
Moreover, tearing of the casing also results in swelling of the vacuum panel and consequent deformation of the vacuum panel itself.
A further drawback which occurs with the gluing of the vacuum panels, or with the skim-finishing thereof, is that the glue, the skimming agent or the polyurethane foam, once they have dried or hardened, retract and tend to tear the outer containment layer.
In order to overcome this drawback, it is known to insert these types of panels inside a protective element, such as a polystyrene element or element made of a similar material.
However, in this case, the thickness of the vacuum panel increases greatly, losing in fact all the advantages associated with the small thickness of the said vacuum panel.
In particular, panels with a fumed silica core manage to reach minimum thermal conductivity values of between 0.004 and 0.0035 w/mK and have high production costs.
Often, some manufacturers, in order to allow the possibility of applying a skim finish directly on top of these vacuum panels without damaging them, glue plates of fibre cement or other materials onto both the surfaces of such a vacuum panel.
The advantages of using such protective fibre cement plates are associated with the fact that these vacuum panels with outer fibre cement plates, if perforated, expand only slightly and therefore in certain situations may be mounted on walls and the skim finish applied directly on them, or they may laid on the ground without having to be coated with thick screeds.
These vacuum panels with fibre cement protective plates glued on them, once perforated, in any case become very soft and therefore could have defects on the wall.
Again in particular, vacuum panels with a glass fibre core manage to reach thermal conductivity values lower than those of fumed silica panels; in fact, said panels have values ranging from 0.0013 to 0.003 W/mK. They therefore offer a significantly better performance than the former and also have the advantage of lower production costs.
Such glass fibre vacuum panels, if damaged or perforated, expand significantly and therefore make it impossible to perform skim-finishing directly on top of them because on the wall, if perforated, they would have significant visible swellings and also cracks in the skim finish.
On this type of panel it would not be possible to glue plates for protecting the panels because, if perforated, they would in any case become swollen.
If applied to flooring, they moreover always require a significantly heavy layer of screed in order to counteract the thrust generated should they be perforated or damaged over time, in order to prevent the flooring from being raised with the formation of cracks on the floor or on the layers of screed.
For this reason, these glass fibre panels always require further protection.
When wall-mounted, in fact, they are always fitted inside interstices or fibre cement or plasterboard counterwalls in order to avoid the aforementioned problems.
The formation of plasterboard or fibre cement counterwalls results in a significant increase in the cost of laying these glass fibre panels, even though, glass fibre based panels, as such, have a lower production cost than fumed silica panels, but once laid the installation cost is very similar to the cost of supplying and laying a fumed silica panel.
If laid on the ground, a screed must be cast on top of these panels, and in this case also the price becomes similar to that of fumed silica panels. Furthermore. as a result of the screed laid on top of the panel, the overall thickness increases significantly.

Summary of the invention

There therefore exists the need to overcome the drawbacks and limitations mentioned with reference to the prior art.
Therefore, it is the main task of the present invention to provide a vacuum panel structure for thermal insulation which allows maintaining very small thicknesses together with a greater superficial and structural strength in general.
Moreover, an important object of the present invention is to provide a vacuum panel structure which may be used directly on walls or on floors without special extra construction work and additional costs.
Yet another object of the present invention is to provide a vacuum panel structure, the thickness and the rigidity of which remain substantially unchanged even in the event of being perforated.
Another object of the present invention is to provide a vacuum panel structure which has a reduced cost and laying time compared to the known vacuum panels.
Said task and said objects are achieved by a vacuum panel structure for thermal insulation according to claim 1.
Preferred characteristic features of the present invention are the subject of the dependent claims.
In particular, the present invention relates to a panel structure for thermal insulation, comprising:

a vacuum panel, for thermal insulation, having a first face and a second face opposite the first face;
a first covering panel being dimensioned and arranged so as to cover completely the first face;
a second covering panel being dimensioned and arranged so as to cover completely the second face;
retaining means apt to secure together the first covering panel and the second covering panel and to retain said vacuum panel between them.

In practical terms, in the panel structure, it is possible to use a vacuum panel of any type, namely with any type of core or casing.
In the panel structure according to the invention, the first face and the second face correspond to the largest faces of the vacuum panel.
In a first embodiment of the invention, obviously provided by way of a non-limiting example of the said invention, the retaining means comprise or consist of at least one strap configured and arranged to surround the first covering panel, the vacuum panel and the second covering panel arranged in sandwich form in said order, as clearly shown by way of example in Figures 1, 2 and 3.
In a second embodiment of the invention, which obviously likewise does not limit said invention, the retaining means comprise or consist of at least one or more staples for each side of the two opposite sides of the panel structure. Each staple is to be understood as comprising, in a manner known per se, a central portion and two opposite clasping or fixing end portions; each of said staples has a first clasping or fixing end portion embedded in the first covering panel and has a second opposite clasping or fixing end portion embedded in the second covering panel, as clearly shown by way of example in Figures 4 and 6.
In another embodiment of the invention, shown by way of example in the perspective view of Figure 5, the retaining means comprise at least a third plate and a fourth plate being dimensioned and arranged so as to cover completely a third face and a fourth face, opposite the third face, of the vacuum panel; said retaining means also comprising a fifth plate being dimensioned and arranged so as to cover completely a fifth face of said vacuum panel, where said fifth plate is to be understood as being substantially orthogonal to the first covering panel, to the second covering panel, and to the third plate and the fourth plate. In particular, the third plate, the fourth plate and the fifth plate, together with the first covering panel and the second covering panel, form part of a single body defining a cover, namely a single covering body, for the vacuum panel. In other words, the first and second covering panels together with the third, fourth and fifth plates form a substantially box-like body having an opening facing the fifth plate. Through this opening it is possible to insert the vacuum panel inside the cover.
The first covering panel and/or the second covering panel are made of one of the following materials: fibre cement, gypsum fibre, solid wood, composite wood (for example laminated or stratified wood or chipboard, oriented strand board (OSB)), wood plastic composite (WPC), marble, cement, plastic (for example polyvinyl chloride (PVC)), ceramic, cotto or other types of materials having a rigidity making them suitable for use.
In particular, the first covering panel and the second covering panel have a thickness of between 0.2 cm and 2.0 cm, preferably between 0.6 cm and 1.0 cm.
The cover may be made for example of plastic, in particular PVC or other similar and technically equivalent plastic material.
Alternatively, the cover may be made of WPC or wood, or OSB.
Alternatively, the vacuum panel may be immersed in cement.
Once solidified, a kind of cement brick comprising inside it the vacuum panel is obtained.
The materials of the plates of the cover, as well as those of the first and second covering panels, must be rigid and not expand when subjected to the pressure exerted on them by a vacuum panel, for thermal insulation, which is perforated. The panel structure may also comprise fastening means associated with or configured to be associated with either the first covering panel or the second covering panel, where these fastening means are configured to allow the said panel structure to be hung from a structural support element or another similar panel structure. In this way, advantageously, it is possible not to use the known "coat dowels"; it is possible to reach any type of height on a façade without using the conventional coat dowels, but by fixing standard dowel plugs to a structural element of the wall and fastening to this standard dowel plug the fastening element associated with or fixed beforehand onto the plate of the panel itself.
Advantageously, the invention according to the present invention manages to overcome the aforementioned problems and may be realized using any type of vacuum panel.
The invention consists in positioning on both sides of a vacuum panel two plates of any type of rigid or semi-rigid material and keeping them joined to the vacuum panel (for example by means a strap or by means of C-shaped elements, such as staples made of metallic material or other materials).
The staples may be fixed using a pneumatic stapler of the type known per se.
In this way stapling, namely fixing by means of a staple, is performed laterally on the two plates, using staples which may be of various types depending on the specific technical requirements for application of the panel structure according to the invention.
Another system, forming the subject of the present patent application, for keeping the panel under pressure is that involving insertion of the vacuum panel inside a cover made of PVC or any other type of material, including cement-based material, so as to be able to keep it under pressure even in the case where the vacuum panel is perforated. Preferably, in order to ensure the necessary rigidity of the said cover, also along or in the vicinity of the edges, the plates and the covering panels of the cover have a thickness of between at least 3 mm and 10 mm.
In general, it is possible to use any thickness, and then, depending on the material with which the cover is made, the thickness of the covering panels may be chosen so that, if the vacuum panel is damaged, the covering panels do not undergo any deformation.
Further characteristic features and advantages of the invention will emerge more clearly from the description of three preferred, but non-exclusive embodiments of a panel structure for thermal insulation according to the invention, with the aid of the drawings provided by way of a non-limiting example in the attached illustrations and listed below.

Brief description of the figures

Reference will be made to the figures of the attached drawings in which:

▪ Figure 1 shows a perspective view of a vacuum panel structure according to the invention;
▪ Figure 2 shows a different perspective view of the vacuum panel structure according to Figure 1.
▪ Figure 3 shows a side view of a first embodiment of a panel structure according to the invention;
▪ Figure 4 shows a side view of a second embodiment of a panel structure according to the invention;
▪ Figure 5 shows a perspective view of a third embodiment of a panel structure according to the invention;
▪ Figure 6 shows a cross-sectional view of the panel structure according to the invention along cross-sectional line VI-VI shown in Figure 3;
▪ Figure 7 shows a transversely sectioned view of the panel structure according to the invention shown in Figure 5;
▪ Figure 8 shows a longitudinally sectioned view of the panel structure according to Figures 5 and 7.

The thicknesses and the curvatures shown in the figures mentioned above must be understood as being purely exemplary and are generally on a larger scale and not necessarily shown in proportion.

Detailed description of preferred embodiments

Below various embodiments and variants of the invention will be described with reference to the figures mentioned above.
Similar components are indicated in the different figures using the same reference number.
In the detailed description which follows, embodiments and further variations with respect to embodiments and variants already described in the said description will be illustrated only with regard to the differences from that already described.
Moreover, the different embodiments and variants described below may be used in combination, where compatible.
With reference initially to Figure 1, according to a first embodiment of the invention, a vacuum panel structure for thermal insulation according to the invention is denoted overall by the number 10.
Such a vacuum panel structure 10 comprises:

a vacuum panel 1, for thermal insulation, having a first face 11 and a second face 12 opposite the first face 11; said first face 11 and second face 12 may be clearly seen in Figure 3;
a first covering panel 2 being dimensioned and arranged so as to cover completely the first face 11;
a second covering panel 3 being dimensioned and arranged so as to cover completely the second face 12;
retaining means 4 configured to secure together the first covering panel 2 and the second covering panel 3 and to retain said vacuum panel 1 between them.

The first face 11 and the second face 12 correspond to the two opposite largest faces of the vacuum panel 10.
According to a preferred aspect of the vacuum panel structure 10 according to the present invention, said structure comprises at least one panel made of sound-absorbing or sound-insulating, i.e. sound-proofing, material. For example, the panel of sound-absorbing material may comprise rubber granules bonded together by polyurethane resins (MDI). For example, the panel of sound-insulating material may comprise or consist of a thin, preferably dual layer, matting which comprises crosslinked polyethylene and rubber.
Preferably, the first covering panel 2 and the second covering panel 3 each comprise an inner face which faces or is directed towards the vacuum panel 11, and an outer face, opposite the inner face.
More preferably, the at least one panel of sound-absorbing or sound-insulating material may be arranged so as to cover or line the outer face of the first covering panel 2 and/or of the second covering panel 3.
Alternatively, the at least one panel of sound-absorbing or sound-insulating material may be arranged between the vacuum panel 11 and the first covering panel 2 and/or between the vacuum panel 11 and the second covering panel 3. In other words, the at least one panel of sound-absorbing or sound-insulating material may be arranged so as to cover or line the inner face of the first covering panel 2 and/or of the second covering panel 3.
In the first embodiment of the vacuum panel structure 10 according to the invention, clearly shown in Figures 1 and 3, the retaining means 4 comprise, or consist of, at least one strap, for example a plurality of straps 4a, 4b, 4c, 4x; furthermore, for example, the retaining means 4 comprises four to twelve straps 4a, 4b, 4c, 4x, in particular ten straps; each strap 4a, 4b, 4c, 4x is configured and arranged to surround the first covering panel 2, the vacuum panel 1 and the second covering panel 3 arranged in sandwich form in said order. The expression "in sandwich form" is understood as meaning that the panel structure is a multilayer structure, in which the vacuum panel 1 is an intermediate layer between the first covering panel 2 and the second covering panel 3. Expressed in yet other words, in the panel structure, the vacuum panel 1 is arranged or enclosed between the first covering panel 2 and the second covering panel 3.
Figure 4 shows schematically a side view of a vacuum panel structure according to the invention in a second embodiment, denoted there overall by the number 200.
In this panel structure 200 the retaining means 40 comprise, or consist of, at least one staple 40a, 40b, 40c, 40x for each side 100a, 100b of two opposite sides 100a, 100b of said panel structure 200; said embodiment of the invention is clearly visible from the side view of Figure 4 and the corresponding cross-section shown in Figure 6.
Each staple 40a, 40b, 40c, 4x comprises a central portion and two opposite clasping or fixing end portions; each of said staples 40a, 40b, 40c, 40x having a first clasping or fixing end portion embedded in said first covering panel 2 and a second opposite clasping or fixing end portion embedded in said second covering panel 3.
A third embodiment of a vacuum panel structure according to the present invention is shown in Figures 5, 7 and 8 and is indicated there by the number 300.
In this panel structure 300 the retaining means 400 comprise at least a third plate 41 and fourth plate 42 being dimensioned and arranged so as to cover completely a third face 13 and a fourth face 14, opposite the third face 13, of the vacuum panel 1.
Preferably, but not exclusively, the retaining means 400 also comprising a fifth plate 43 being dimensioned and arranged so as to cover completely a fifth face 15 of said vacuum panel 1, where said fifth plate 43 is understood as being substantially orthogonal to the first covering panel 2, to the second covering panel 3 and to the third plate 41 and the fourth plate 42.
Again preferably, as schematically shown in Figure 5, the third plate 41, the fourth plate 42 and the fifth plate 43, together with said first covering panel 2 and said second covering panel 3, form part of a single body defining a cover 50, or covering assembly, for said vacuum panel 1.
Said cover 50 is therefore shaped so as to house a vacuum panel 1 without play, so as to prevent the swelling thereof also in the case of damage.
The first covering panel 2 and/or said second covering panel 3 are made of one of the following materials: fibre cement, fibre gypsum, solid wood, composite wood (for example laminated or stratified wood or chipboard, oriented strand board (OSB), wood plastic composite (WPC), marble, cement, plastic (for example polyvinyl chloride (PVC)), ceramic, cotto or other types of materials having a rigidity making them suitable for use.
Preferably, the first covering panel 2 and the second covering panel 3 have a thickness of between 0.2 cm and 2.0 cm, more preferably between 0.6 cm and 1.0 cm. Even more preferably, the materials must be rigid and not expand when subjected to the pressure of the perforated panel.
The panel structure 100, 200, 300 may comprise fastening means 60 associated with or apt to be associated with either the first covering panel 2 or the second covering panel 3, or the cover 50, and configured to allow the said panel structure 100, 200, 300 to be joined to or hung from a structural support element, for example a frame of a ventilated wall, or another similar panel structure 100, 200, 300.
Said fastening means 60 comprise, for example L-shaped or Z-shaped brackets 61 and 62, as can be seen in Figure 1, comprising in turn a portion for fixing to the covering panels 2 and 3 and a hanging portion with one or more holes for corresponding dowel plugs for performing securing to a support.
It can therefore be understood how with a vacuum panel structure according to the present invention the predefined objects and task may be achieved.
In particular, with the present invention it has been possible to provide a vacuum panel structure whereby, whereas until now a glass fibre vacuum panel could be used directly on walls or floors only with the aid of a fibre cement or plasterboard counterwall - or in the case of floors, only with the aid of considerably thicknesses of screed - such a vacuum panel may now be finally used without the aforementioned additional construction work.
The panel structure for thermal insulation according to the invention is such that, even if the vacuum panel is perforated, its thickness remains unchanged owing to the covering panels which are applied to the vacuum panel, such that the same vacuum panel does not vary its volume and is kept in any case stably rigid and under pressure.
With this invention it has been possible to provide a panel structure which simplifies laying, reduces the laying costs. speeds up the working time and results in a reduction in the final overall thicknesses on walls or floors, while also guaranteeing for the end user no risk of any type of swelling, as well as ensuring over time the same degree of mechanical resistance to impacts and adverse weather conditions as that achieved with the traditional laying of a fibre cement counterwall.
Moreover, the aforementioned straps used to tighten the two covering panels around the vacuum panel do not create any type of heat bridge around the vacuum panel since they have a negligible thickness. Moreover, preferably, the straps are made of a material which, depending on the needs, may also be made of plastic (for example PVC), so that the heat bridge is irrelevant and negligible during the calculation of the heat or cold transmission values.
In the case where particular fire resistance properties are required it is possible to use, as retaining means, metal staples which result in the panel structure being particularly resistant also in the event of fires.
Moreover, with the present invention it has been possible to provide a vacuum panel structure which, when used for the construction of a wall provided a skim finish performed directly on the vacuum panels, allows certain heights (about 4 m) to be exceeded since all the wall-mounted insulating materials, in order to be used above such heights, require the use of dowl plugs. Whereas the vacuum panels of the known type cannot be fixed using dowel plugs, because they would be perforated and would therefore lose their insulating properties, and hence always require the use of fibre cement counterwalls or are glued behind ventilated systems, the vacuum panel structure according to the present invention allows the use of hanging brackets, with the result that it can be mounted also at heights of more than 4 m.
The present invention is to be understood as being able to be realized using any type of vacuum panel commercially available to date and produced by any company.
Said vacuum panels may therefore be used also with panels having a fumed silica core, ensuring that the panels, even though perforated, do not become softer because kept under pressure by the sandwich.
Preferably, the vacuum panel in the structure according to the invention is a vacuum panel with a glass fibre core. In fact, panels with a glass fibre core guarantee a better performance and are cheaper to produce. Owing to the presence of the first covering panel 1 and the second covering panel 1, it is possible to prevent the expansion of the glass fibre panel and therefore an increase in its thickness. With this invention, said drawback is avoided, while the further advantages of vacuum panels are maintained. It is therefore possible to achieve the same results, in terms of impact resistance and fire resistance, as the counterwall laying system.
The present invention has been described hitherto with reference to preferred embodiments thereof. It is to be understood that other embodiments relating to the same inventive idea may exist, as defined by the scope of protection of the claims which are illustrated hereinbelow.

Claims

Panel structure (100, 200, 300) for thermal insulation, comprising:
- a vacuum panel (1), for thermal insulation, having a first face (11) and a second face (12) opposite the first face (11);

- a first covering panel (2) being dimensioned and arranged so as to cover completely the first face (11);

- a second covering panel (3) being dimensioned and arranged so as to cover completely the second face (12);

- retaining means (4, 40, 400) configured to secure together the first covering panel (2) and the second covering panel (3) and to retain said vacuum panel (1) between them.
Panel structure (100) according to the preceding claim, wherein the first face (11) and the second face (12) correspond to the two opposite largest faces of said vacuum panel (1).
Panel structure (100) according to any one of the preceding claims, wherein the retaining means (4) comprise or consist of at least one strap (4a, 4b, 4c) configured and arranged to surround said first covering panel (2), said vacuum panel (1) and said second covering panel (3) being arranged in sandwich form in said order.
Panel structure (200) according to one or more of the preceding claims, wherein said retaining means (40) comprise or consist of at least one staple (40a, 40b, 40c) for each side (100a, 100b) of two opposite sides (100a, 100b) of said panel structure (100).
Panel structure (200) according to claim 4, wherein each of said staples (40a, 40b, 40c) comprises a central portion and two opposite clasping end portions, each of said staples (40a, 40b, 40c) having a first clasping end portion embedded in said first covering panel (2) and a second opposite clasping end portion embedded in said second covering panel (3).
Panel structure (300) according to any one of the preceding claims 1 to 3, wherein said retaining means (400) comprise at least a third plate (41) and fourth plate (42) being dimensioned and arranged so as to cover completely a third face (13) and a fourth face (14), opposite said third face (13), of the vacuum panel (1), said retaining means (4) further comprising a fifth plate (43) being dimensioned and arranged so as to cover completely a fifth face (15) of said vacuum panel (1), wherein said fifth plate (43) is understood as being substantially orthogonal to the first covering panel (2), to the second covering panel (3), and to the other third plate (41) and fourth plate (42).
Panel structure (300) according to the preceding claim, wherein said third plate (41), said fourth plate (42) and said fifth plate (43), together with said first covering panel (2) and said second covering panel (3), form part of a single body defining a cover (50) for said vacuum panel (1).
Panel structure (100, 200, 300) according to any one of the preceding claims, wherein said first covering panel (2) and/or said second covering panel (3) are made of any one of the following materials: plastic material, fibre cement, gypsum fibre, solid wood, composite wood, wood plastic composite (WPC), marble, cement, ceramic, cotto, or other types of materials having a rigidity making them suitable for use.
Panel structure (100) according to any one of the preceding claims, wherein the first covering panel (2) and the second covering panel (3) have a thickness of between 0.2 cm and 2 cm.
Panel structure (100) according to any one of the preceding claims, comprising fastening means (60) associated with or apt to be associated with either the first covering panel (2) or the second covering panel (3) and configured to allow them to be joined to a structural support element or to another panel structure (100).
Panel structure (100) according to any one of the preceding claims, wherein said first covering panel (2) and said second covering panel (3) each comprise an inner face, which faces or is directed towards said vacuum panel (11), and an outer face, opposite to the inner face; and wherein said panel structure comprises at least one panel made of sound-absorbing or sound-insulating material; and wherein said panel made of sound-absorbing or sound-insulating material is arranged to cover the outer face of said first covering panel (2) and/or of said second covering panel (3), or said at least one panel made of sound-absorbing or sound-insulating material is arranged to cover or line the inner face of said first covering panel (2) and/or of said second covering panel (3).