Multi-layer insulation panel, method for producing a multi-layer insulation panel, and use of a mineral material as the thermal insulation layer

Abstract

The invention relates to a multi-layer insulation panel (10), containing at least one fibre- or chip-layer having fibres or chips which are held together by an in particular inorganic binder, in particular a wood-wool or wood-chip layer (2) having wood-wool fibres or wood chips; and at least one thermal insulation layer (3), which comprises a mineral foam and / or a porous mineral material. The multi-layer insulation panel has advantageous processing properties, is easy to handle, and is readily recyclable.

Description

[0001] Multi-layer insulation board, method for producing a multi-layer insulation board and use of a mineral material as a thermal insulation layer

[0002] The present invention is concerned with multi-layer insulation boards, processes for producing multi-layer insulation boards and uses.

[0003] Multi-layer insulation boards are used, for example, for cladding and thermally insulating ceilings and walls. Multi-layer insulation boards with at least one layer of wood wool (often made of cement-bonded wood wool) and at least one layer of a plastic material, such as expanded polystyrene foam (EPS), are frequently used. Such boards are described, for example, in EP 3 144 137. They have a very high compressive strength. Fasteners such as dowels or screws are difficult to press in, which prevents local indentation and thus deflection of the covering layer and the entire multi-layer insulation board. They are lightweight and therefore easy and efficient to process. However, due to the plastic material, they are not ideal for fire protection and therefore cannot be used for all applications.

[0004] Such material combinations are also disadvantageous with regard to recyclability, since the plastic material cannot be completely separated from the wood wool layer without further ado.

[0005] Also known are multi-layer insulation boards with a bonded wood wool layer and an insulating layer of mineral wool (rock wool or glass wool). While such boards are advantageous due to their non-combustibility, they are comparatively heavy, and their compressive strength is also not particularly high. The latter typically results in indentations near the fastening points, thus leading to the deflection of the covering layer and the entire multi-layer insulation board.

[0006] It is an object of the present invention to overcome the aforementioned disadvantages. In particular, it is an object of the present invention to provide a multi-layer insulation board that is as optimized as possible with regard to recyclability, fire protection properties, processing properties, and aesthetics.

[0007] A multi-layer insulation board according to the invention comprises at least one layer with fibers or chips held together by a binder, in particular an inorganic one; and at least one thermal insulation layer comprising a mineral foam and / or a porous mineral material.

[0008] The fibers or shavings can be natural fibers, for example, particularly wood wool fibers or wood shavings. Alternatively, they can be fibers or shavings from corn, corn stalks, reeds, miscanthus (reed grass), straw, hemp, flax, cannabis, bamboo, or barley. Initial findings show that at least some of these plants have a high CO2 binding capacity and are therefore particularly climate-friendly.

[0009] Fibers are typically particularly long and flexible and are usually specially manufactured. For the purposes of the invention, chips with a length of at least 7 cm and a thickness of no more than 3 mm are understood as fibers.

[0010] In particular, wood wool or wood wool fibres (usually specially manufactured) are referred to as particularly long, flexible and splinter-free wood shavings. For the purposes of the invention, wood shavings with a length of at least 7 cm and a thickness of not more than 3 mm are understood to be wood wool fibres. The fibres, in particular the wood wool fibres, comprise in particular fibres with i. a length of at least 2.5 cm, at least 7 cm or at least 10 cm; and / or not more than 50 cm, not more than 30 cm or not more than 20 cm; and / or ii. a width of at least 0.5 mm or at least 0.8 mm or at least 1.0 mm or at least 2.0 mm; and / or not more than 10 mm, not more than 6 mm or not more than 4 mm (with ranges from 0.5 mm to 10 mm, or from 0.8 mm to 6 mm or from 1.0 mm to 4.0 mm being preferred); and / or iii.a thickness of at least 0.1 mm or at least 0.3 mm or at least 0.5 mm; and / or not more than 3 mm or not more than 2 mm or not more than 1 mm.

[0011] Preferably, predominantly (i.e. more than 50 wt.% of the fiber material, in particular the wood) fibers, in particular wood wool fibers, with these dimensions are contained, particularly preferably substantially only fibers, in particular only wood wool fibers, with these dimensions are contained.

[0012] The wood chip layer, which is held together by a particularly inorganic binder, can be a cement-bonded particleboard according to DIN EN 633 (December 1993). In principle, however, all binders described herein in connection with fiber layers, especially wood wool layers, can also be used for chip layers, especially for wood chip layers.

[0013] Mineral foam and other porous mineral materials are known in the art. They are widely used as construction materials and are known, for example, as aerated concrete blocks or cellular concrete. Well-known trade names include Multipor® from Xella, Geolyth® mineral foam from the company of the same name, and AIRIUM from Lafarge Holcim. However, these materials are relatively brittle, particularly at the edges and corners, and have low compressive strength in some areas, making it difficult to install the panels without damage (e.g., from fingerprints); this compromises their aesthetic appearance. However, this disadvantage can be easily compensated for in combination with a fiber or chip layer, particularly a wood wool or chip layer. The fiber or chip layer, especially the wood wool or chip layer, protects against mechanical damage both during and after construction.Excessive point pressure loads are also prevented by the fiber or chip layer, especially the wood wool or chip layer, by absorbing and distributing the pressure. This allows the advantageous properties of the porous or foamed mineral materials to be utilized as an insulating layer in multi-layer insulation boards.

[0014] In addition, the recyclability is improved compared to multi-layer insulation boards with EPS thermal insulation layer, since no plastic contaminants enter the recycled fibers / chips, especially the wood wool / wood chips, or the inorganic material.

[0015] In addition, it has surprisingly been shown that the sound absorption of multi-layer insulation boards according to the invention is also improved compared to comparable boards with EPS thermal insulation layer.

[0016] In advantageous embodiments, the thermal insulation layer consists essentially of mineral foam and / or porous mineral material. This means that the thermal insulation layer comprises more than 80 wt.%, preferably more than 85 wt.%, more preferably more than 90 wt.%, particularly preferably more than 95 wt.% of mineral foam and / or porous mineral material. The density of the mineral foam or the porous mineral material is advantageously between 20 kg / m 3 and 200 kg / m 3 , preferably between 20 kg / m 3 and 140 kg / m 3 , particularly preferably between 30 kg / m 3 and 80 kg / m 3 .

[0017] In further embodiments, the mineral foam and / or the porous mineral material is cement-based.

[0018] The mineral foam and / or the porous mineral material can be, for example, foamed or porous concrete; for example, reference is made to those described in EP 3 789 362 or referred to therein (incorporated herein by reference). Materials that are essentially free of alkali metal sulfate and alkaline earth metal sulfate are preferred. Also suitable is foam glass, available, for example, under the trade name Foamglas® from Owens Corning.

[0019] In further preferred embodiments, the mineral foam and / or the porous mineral material is obtained from a suspension of, in particular, inorganic particles and at least one surfactant which makes the surface of the, in particular, inorganic particles hydrophobic. The material is obtained, for example, from a suspension by drying and, if appropriate, subsequent sintering. Materials of this type are known, for example, from EP 3 818 027, the disclosure of which is incorporated herein by reference. These materials are also relatively brittle and, in particular, fragile at the edges and corners and, in some places, have little compressive strength, which makes it difficult to assemble such panels without damage (e.g. from fingerprints); this has a negative impact on the aesthetics. However, in combination with a fiber or chip layer, in particular a wood wool or wood chip layer, this disadvantage can easily be compensated for; the fiber or chip layerThe chipboard layer, especially the wood wool or wood chipboard layer, protects against mechanical damage both during and after the construction phase. Excessive point pressure loads are also prevented by the fiber or chipboard layer, especially the wood wool or wood chipboard layer, by absorbing and distributing the pressure. This allows the advantageous properties of the porous or foamed mineral materials to be utilized as an insulating layer in multi-layer insulation boards.

[0020] In principle, particularly preferred inorganic particles in this context are those that are geopolymers or are suitable for forming geopolymers. Geopolymers are understood to be inorganic silicate-based binders. Aluminosilicates and calcium silicates are particularly preferred. Exemplary compositions, incorporated herein by reference, are also described, for example, in WO 2011 / 106815 A1.

[0021] In advantageous embodiments, the fiber or chip layer, in particular the wood wool or wood chip layer, has a thickness in the range from 1 mm to 60 mm, preferably from 2 mm to 45 mm, more preferably from 3 mm to 30 mm, particularly preferably from 5 mm to 20 mm.

[0022] In advantageous embodiments, the thermal insulation layer has a thickness in the range from 10 mm to 500 mm, preferably from 15 mm to 400 mm, particularly preferably from 20 mm to 300 mm.

[0023] In advantageous embodiments, the fibers or chips, in particular the wood wool fibers or wood chips, are arranged in an irregular geometry, wherein the structure of the fiber or chip layer, in particular the wood wool or wood chip layer, has a porosity of more than 30 vol.%, preferably more than 40 vol.%, more preferably more than 50 vol.%, and particularly preferably more than 60 vol.%. It has been proven that this alone can achieve a particularly advantageous distribution of the compressive load. In highly compacted fiber or chip layers, in particular wood wool or wood chip layers, a lower porosity can also be present within the scope of the invention.

[0024] In further preferred embodiments, the density of the fiber layer, in particular the wood wool layer, is between 200 kg / m 3 and 1,350 kg / m 3 , especially between 250 kg / m 3 and 1,150 kg / m 3, particularly preferably between 300 kg / m 3 and 800 kg / m 3 .

[0025] In preferred embodiments, the density of the chip layer, in particular the wood chip layer, is in the range of 800 kg / m 3 up to 1,800 kg / m 3 , preferably 900 kg / m 3 up to 1,600 kg / m 3 , particularly preferably 1,000 kg / m 3 up to 1,500 kg / m 3 .

[0026] The particularly inorganic binder in the fiber or chip layer, especially the wood wool or wood chip layer, is preferably cement, Portland cement, white cement, gray cement, high-alumina cement, magnesia, caustic magnesia, a silicate, gypsum (e.g., natural gypsum or FGD gypsum), anhydrite, clay, loam, kaolin, or a mixture thereof. Such binders have been shown to achieve a particularly advantageous distribution of compressive loads, particularly in combination with the aforementioned porosities.

[0027] Advantageously, the amount of inorganic binder in the fiber layer, in particular the wood wool layer, is less than 90 wt.%, preferably less than 80 wt.%, more preferably less than 70 wt.%; particularly preferably, the amount of inorganic binder in the fiber layer, in particular the wood wool layer, is in the range from 50 wt.% to 70 wt.%.

[0028] In further preferred embodiments, the binder content of the chip layer, in particular the wood chip layer, is in the range from 50 wt.% to 90 wt.%, preferably from 60 wt.% to 85 wt.%, particularly preferably from 70 wt.% to 80 wt.%.

[0029] In further embodiments, the multi-layer insulation board comprises a bonding layer, which is arranged between the fiber or chip layer, in particular the wood wool or wood chip layer, and the thermal insulation layer and adjoins the latter, wherein the material of the bonding layer is essentially mineral. For this purpose, known mineral adhesives can be used, for example. This has the advantage that - if a bonding layer is present - it does not impair recyclability, since it has essentially the same mineral character as the thermal insulation layer or the binder of the fiber or chip layer, in particular the wood wool or wood chip layer. In particular, the material of the bonding layer can be the same as that of the thermal insulation layer. Alternatively, the material of the bonding layer can be a cement slurry or a cement slurry.

[0030] However, the use of other materials in the bonding layer is also possible. Materials selected from the following group are possible in the bonding layer: physically curing adhesives, especially solvent-based wet adhesives, contact adhesives, dispersion adhesives, hot melt adhesives, and plastisols; chemically curing adhesives, especially polyaddition adhesives, polycondensation adhesives, and polymerization adhesives; and mixtures thereof. Polyurethane adhesives, white glues, and hot melt adhesives are currently particularly preferred. The material in the bonding layer can also be bio-based adhesives, for example, based on casein, tannin, or other starches.

[0031] As an alternative to a connecting layer, it is also possible within the scope of the invention for the fiber or chip layer, in particular the wood wool or wood chip layer, to be at least partially anchored in the thermal insulation layer. In this way, the connection between the layers can be effected directly. This can occur directly during the production of the thermal insulation layer, for example by applying the fiber or chip layer, in particular the wood wool or wood chip layer, from above and pressing it onto it or partially pressing it in before the foam or porous material has finished curing. It is also possible for the thermal insulation layer to be applied to the fiber or chip layer, in particular the wood wool or wood chip layer, from above or from the side in an as yet uncured state and to at least partially extend into the fiber or chip layer, in particular the wood wool or wood chip layer.

[0032] A further aspect of the invention relates to a method for producing a multi-layer insulation board, in particular as described herein, wherein a thermal insulation layer comprising a mineral foam and / or a porous mineral material is bonded to a fiber or chip layer with fibers or chips held together by an inorganic binder in such a way that the bond is effected by means of a particularly substantially mineral bonding layer; or the fiber or chip layer is at least partially anchored in the thermal insulation layer; or the bond is effected with the particularly inorganic binder of the fiber or chip layer of the wood wool or wood chip layer itself. In this case, the fiber or chip layer with fibers or chips can in each case be a wood wool or wood chip layer with wood wool fibers or wood chips.

[0033] A further aspect of the invention relates to the use of a mineral foam and / or a porous mineral material as a thermal insulation layer in a multi-layer insulation board, which in particular comprises at least one fiber or chip layer with fibers or chips held together by an inorganic binder. The fiber or chip layer with fibers or chips can be a wood wool or wood chip layer with wood wool fibers or wood chips. Such a use has not yet been proposed in the prior art, and it provides the advantages discussed herein.

[0034] The invention is explained in more detail below with reference to exemplary embodiments, whereby the invention is not to be restricted to these exemplary embodiments.

[0035] They show:

[0036] Fig. 1 a multi-layer insulation board (schematic);

[0037] Fig. 2 a multi-layer insulation board with connecting layer

[0038] (schematic);

[0039] Fig. 3 a multi-layer insulation board with partial anchoring of the wood wool or wood chip layer in the thermal insulation layer (schematic).

[0040] Fig. 1 schematically illustrates in cross-section a multi-layer insulation board 1 according to the invention, as described above. It comprises a wood wool or wood chip layer 2 and a thermal insulation layer 3. The wood wool or wood chip layer 2 comprises wood wool fibers or wood chips held together by an inorganic binder. The thermal insulation layer 3 comprises a mineral foam and / or a porous mineral material. Here and also in the other embodiments shown, it is of course possible to provide at least one further wood wool or wood chip layer 2, in particular such that the thermal insulation layer 3 is covered on both sides by wood wool or wood chip layers 2 (not illustrated). Fig. 2 schematically illustrates another multi-layer insulation board 1 according to the invention. In this embodiment, the wood wool or wood chip layer 2 is bonded to the thermal insulation layer by a connecting layer 4.The connecting layer 4 is, for example, of a mineral nature and serves as an adhesion promoter / adhesive layer between the inorganically bound wood wool or wood chip layer 2 and the mineral thermal insulation layer 3.

[0041] Fig. 3 schematically illustrates a further multi-layer insulation board 1 according to the invention. In this exemplary embodiment, the wood wool layer 2 is partially anchored in the thermal insulation layer 3 in an area 5. (In the case of a wood chip layer 2, the thermal insulation layer 3 adheres essentially only to the surface of the wood chip layer 2.) This can advantageously take place directly during the production of the thermal insulation layer 3, when this has not yet (fully) cured and the wood wool or wood chip layer 2 can still be at least partially pressed into the thermal insulation layer 3 or pressed against it; or the thermal insulation layer 3 is applied to the wood wool or wood chip layer 2 from the side or from above in a not yet (fully) cured state and can still at least partially run into it.Alternatively, a solid layer of wood wool can be pressed from above onto a not yet (fully) cured mineral foam 3, whereby the mineral foam 3 itself causes the bonding.

Claims

Patent claims 1. Multi-layer insulation board (1) comprising at least one fiber or chip layer with fibers or chips held together by a binder, in particular an inorganic one; and at least one thermal insulation layer (3) comprising a mineral foam and / or a porous mineral material.

2. Multi-layer insulation board (1) according to claim 1, wherein the fiber or chip layer is a wood wool or wood chip layer (2) with wood wool fibers or wood chips.

3. Multi-layer insulation panel (1) according to one of claims 1 and 2, wherein the thermal insulation layer (3) consists essentially of mineral foam and / or porous mineral material.

4. Multi-layer insulation board (1) according to any one of claims 1 to 3, wherein the mineral foam and / or the porous mineral material is cement-based.

5. Multi-layer panel (1) according to any one of claims 1 to 4, wherein the mineral foam and / or the porous mineral material is selected from the group consisting of foamed or porous concrete; foam glass.

6. Multi-layer insulation board (1) according to one of claims 1 to 5, characterized in that the mineral foam and / or the porous mineral material is essentially free of alkali sulfate and alkaline earth sulfate.

7. Multi-layer insulation board (1) according to one of claims 1 and 2, wherein the mineral foam and / or the porous mineral material is obtained from a suspension of inorganic particles and at least one surfactant which makes the surface of the inorganic particles hydrophobic.

8. Multi-layer insulation board (1) according to claim 7, wherein the mineral foam and / or the porous mineral material is obtained from the suspension by drying, optionally followed by sintering.

9. Multi-layer insulation board (1) according to one of claims 7 and 8, wherein the inorganic particles are selected from the group of geopolymers, in particular aluminosilicates and calcium silicates; and inorganic particles suitable for the formation of geopolymers.

10. Multi-layer insulation board (1) according to any one of claims 1 to 9, wherein the at least one fiber or chip layer, in particular the at least one wood wool or wood chip layer (2), has a thickness in the range of 1 mm to 60 mm, preferably of 2 mm to 45 mm, more preferably from 3 mm to 30 mm, particularly preferably from 5 mm to 20 mm.

11. Multi-layer insulation board (1) according to one of claims 1 to 10, wherein the thermal insulation layer (3) has a thickness in the range of 10 mm to 500 mm, preferably 15 mm to 400 mm, particularly preferably 20 mm to 300 mm.

12. Multi-layer insulation board (1) according to one of claims 1 to 11, wherein the inorganic binder shall be cement, Portland cement, white cement, grey cement, alumina cement, magnesia, caustic magnesia, a silicate, gypsum, anhydrite, clay, loam, kaolin or a mixture thereof.

13. Multi-layer insulation board (1) according to one of claims 1 to 12, comprising a connecting layer (4) which is arranged between and adjacent to the fiber or chip layer, in particular the wood wool or wood chip layer (2) , and the thermal insulation layer (3).

14. Multi-layer insulation board (1) according to one of claims 1 to 13, wherein the fiber or chip layer, in particular the wood wool or wood chip layer (2) , is at least partially anchored in the thermal insulation layer (3) in an area (5).

15. Method for producing a multi-layer insulation board, in particular a multi-layer insulation board (1) according to one of the preceding claims, wherein a thermal insulation layer (3) comprising a mineral foam and / or a porous mineral material is combined with a fiber or chip layer with fibers or chips, in particular a wood wool or wood chip layer (2) with wood wool fibers or wood chips, which are held together by a binder, in particular an inorganic one, such that - the connection is effected by means of a bonding layer, in particular a substantially mineral bonding layer; or - the fiber or chip layer, in particular the wood wool or wood chip layer (2) , is at least partially anchored in the thermal insulation layer (3); or - the bond with the inorganic binder of the fiber or chip layer, in particular the wood wool or wood chip layer (2) itself is effected.

16. Use of a mineral foam and / or a porous mineral material as a thermal insulation layer (3) in a multi-layer insulation board (1) which in particular comprises a fiber or chip layer with fibers or chips held together by an inorganic binder, wherein the fiber or chip layer with fibers or chips is in particular a wood wool or wood chip layer (2) with wood wool fibers or wood chips.