COMPOSITE PANEL

Description

Field of invention

[0001] The present invention relates to the field of composite panels, in particular intended for aircraft or nautical furniture.

[0002] The present disclosure relates to a method for producing a composite panel, and a composite panel, for example obtained by said method. State of the art

[0003] Composite panels are now commonly used for aircraft furniture or nautical furniture.

[0004] In particular, French patent No. FR 2 563 153 B1 is known in the state of the art, which relates to a composite panel, in particular intended for aircraft furniture. The subject of this invention of the state of the art is a composite panel comprising a central core formed from a honeycomb-type panel coated on both sides with at least one layer of fabric pre-impregnated with suitable resin, in which at least one of the sides of said panel thus coated is covered with a thin wood veneer put in place by simple hot pressure, the central core + fabric + veneer assembly being assembled and secured during a single operation.

[0005] Also known in the state of the art is French patent No. FR 2 872 085 B1, which relates to a composite panel for aircraft furniture. The subject of this invention of the state of the art is a composite panel, in particular intended for aircraft furniture, comprising a central core formed from a honeycomb-type panel coated on both sides with at least one layer of fabric pre-impregnated with suitable resin, at least one of the sides of said panel being covered with a thin wood veneer, in which, between said thin wood veneer and said layer of pre-impregnated fabric, a layer of rigid plastic foam and a second layer of fabric pre-impregnated with resin are interposed, the layer of foam being interposed between the two layers of fabric, the assembly being assembled and secured under pressure and heat during a single operation.

[0006] Also known in the prior art is French patent No. FR 2 962 362 B1, which relates to a composite panel for aircraft furniture. The subject of this prior art invention is a composite panel, in particular intended for aircraft furniture, comprising a central core formed from a honeycomb-type panel coated on both sides with at least one layer of fabric pre-impregnated with suitable resin, at least one of the two sides of said panel being covered with a thin wood veneer, the assembly being assembled and secured under pressure and heat during a single operation. According to this prior art invention, between said thin wood veneer and said layer of pre-impregnated fabric is interposed an aluminum film, said aluminum film being secured on one of the sides of said wood veneer by means of a layer of glue.

[0007] For certain types of porous veneer, resin rises from the pre-impregnated fabric may appear on the visible face of the veneer during the single-step curing described in patent No. FR 2 563 153 B1. Statement of the invention

[0008] The present disclosure intends to remedy the drawbacks of the prior art by proposing a method for producing a composite panel, in particular intended for aircraft or nautical furniture, making it possible to create a waterproof barrier on the face in contact with the resin-pre-impregnated material, while minimizing the impact on the mass of the composite panel and ensuring better bonding of the veneer to the panel.

[0009] To this end, the present disclosure relates, in its most general sense, according to an unclaimed aspect, to a method for producing a composite panel, in particular intended for aircraft or nautical furniture, said composite panel comprising a central core formed from a low-density structured material type core coated on both sides with at least one layer of resin-pre-impregnated material, at least one of the sides of said panel being covered with a veneer, comprising the following two manufacturing steps: baking said veneer with a film of glue, said film of glue sticking to one of the faces of said veneer; and baking said veneer and the film of glue on said at least one layer of resin pre-impregnated material.

[0010] The method according to this aspect of the present disclosure makes it possible to create a waterproof barrier on the face in contact with the resin pre-impregnated material in order to prevent resin from rising onto veneers.

[0011] The process according to this aspect makes it possible to ensure better adhesion of the veneer to the sandwich by adding a film of glue which helps to hold the veneer on the composite panel.

[0012] The process according to this aspect makes it possible to minimize the impact on the mass of the composite panel by adding only a film of glue on either side of the composite panel.

[0013] It allows a weight saving of 30% compared to traditional manufacturing where the decorative assembly of veneer layers is cold bonded with neoprene in a second step.

[0014] According to one of the implementation variants, the addition of aluminum between two adhesive films in the composite panel makes it possible to improve the rigidity of the composite panel and its fire resistance.

[0015] The process allows the production of structural panels and decorative panels.

[0016] Advantageously, the bonding of said adhesive film is carried out by hot pressing on one of the faces of said veneer.

[0017] According to one embodiment, said low-density structured material is of the honeycomb type.

[0018] According to another embodiment, said low density structured material is of the foam type.

[0019] According to one embodiment, the step of baking said veneer with said glue film is carried out at a temperature between 110°C and 165°C.

[0020] According to a particular embodiment, the step of cooking said veneer with said adhesive film is carried out at a temperature between 110°C and 140°C.

[0021] According to one embodiment, the step of cooking said veneer with said glue film lasts between 20 seconds and 30 minutes.

[0022] According to a particular method of implementation, the step of cooking said veneer with said film of glue lasts between 2 minutes and 10 minutes.

[0023] According to one embodiment, the step of cooking said veneer with said glue film is carried out in a hot compression press under a pressure of between 12 and 25 bar.

[0024] According to one embodiment, the step of baking said veneer and the glue film on said at least one layer of resin pre-impregnated material is carried out at a temperature between 100°C and 150°C.

[0025] According to a particular embodiment, the step of baking said veneer and the adhesive film on said at least one layer of resin pre-impregnated material is carried out at a temperature between 125°C and 135°C.

[0026] According to one embodiment, the step of baking said veneer and the glue film on said at least one layer of resin pre-impregnated material lasts between 20 and 360 minutes.

[0027] According to a particular embodiment, the step of baking said veneer and the glue film on said at least one layer of resin-pre-impregnated material lasts between 90 and 120 minutes.

[0028] According to one embodiment, the step of baking said veneer and the glue film on said at least one layer of resin pre-impregnated material is carried out in a hot compression press under a pressure of between 0.3 and 5 bar.

[0029] According to another embodiment, the step of baking said veneer and the glue film on said at least one layer of resin pre-impregnated material is carried out in an oven.

[0030] According to another embodiment, the step of baking said veneer and the glue film on said at least one layer of resin pre-impregnated material is carried out in an autoclave.

[0031] According to one embodiment, said veneer is made of wood with a thickness of a few tenths of a millimeter.

[0032] Preferably, said wood veneer has a thickness of between 0.4 mm and 1 mm.

[0033] According to one embodiment, between said veneer and said layer of pre-impregnated material is interposed an aluminum film with a thickness of a few tenths of a millimeter.

[0034] Preferably, said aluminum film has a thickness of between 0.05 mm and 0.2 mm.

[0035] According to one variant, said method further comprises a step of adding a flame-retardant impregnating agent.

[0036] According to one embodiment, said layer of pre-impregnated material is composed of fabrics.

[0037] According to another embodiment, said layer of pre-impregnated material is composed of unidirectional sheets.

[0038] Advantageously, said layer of pre-impregnated material is composed of fibers of the following group: glass, hybrids, carbon, aramid, linen, bamboo and hemp.

[0039] The present invention relates to a composite panel, in particular intended for aircraft or nautical furniture, for example obtained by implementing the method mentioned above.

[0040] To this end, the present invention relates to a composite panel as defined in claim 1.

[0041] Embodiment options are defined in the dependent claims.

[0042] According to one embodiment, said composite panel is flat.

[0043] According to another embodiment, said composite panel is shaped. Brief description of the drawings

[0044] The invention will be better understood with the aid of the description, given below for purely explanatory purposes, of an embodiment of the invention, with reference to the Figures in which: There Figure 1 illustrates the method according to the present disclosure; The Figure 2 represents a composite panel according to the present invention; and The Figure 3 represents a variant of the composite panel according to the present invention. Detailed description of embodiments of the invention

[0045] The present disclosure relates to a method for producing a composite panel 10, in particular intended for aircraft or nautical furniture, said composite panel 10 comprising a central core 11 formed from a core 12 of low-density structured material type coated on both sides with at least one layer 13 of resin-prepreg material, at least one of the sides of said panel 10 being covered with a veneer 14. The method according to the present disclosure comprises the following two manufacturing steps: baking said veneer 14 with a film of glue 15, said film 15 of glue sticking to one of the faces of said veneer 14; and baking said veneer 14 and the film of glue 15 on said at least one layer 13 of material pre-impregnated with resin.

[0046] There Figure 1 illustrates the different stages of the process.

[0047] There Figure 2 represents a composite panel 10 according to the present invention.

[0048] We observe on the Figure 2 a composite panel 10 comprising a central core 11 formed from a core 12 of low-density structured material type coated on both sides with at least one layer 13 of resin-prepreg material, at least one of the sides of said panel 10 being covered with a veneer 14. We also observe on the Figure 2 a film of glue 15, said film 15 of glue sticking to one of the faces of said veneer 14.

[0049] There Figure 3 represents a variant of the composite panel according to the present invention.

[0050] We observe on the Figure 3 a composite panel 10 comprising a central core 11 formed from a core 12 of low-density structured material type coated on both sides with at least one layer 13 of resin-prepreg material, at least one of the sides of said panel 10 being covered with a veneer 14. We also observe on the Figure 3an adhesive film 15, said adhesive film 15 sticking to one of the faces of said veneer 14. In addition, in the composite panel 10 illustrated Figure 3 , an aluminum film 16 is interposed between said plating 14 and said layer 13 of pre-impregnated material. A flame-retardant impregnating agent 17 is also shown Figure 3 .

[0051] The process creates a waterproof barrier on the face in contact with the resin-pre-impregnated material to prevent resin from rising onto the veneers.

[0052] The process also ensures better bonding of the veneer to the sandwich.

[0053] The process allows the production of structural panels and decorative panels.

[0054] In one embodiment, the bonding of said adhesive film 15 to one of the faces of said veneer 14 is carried out by hot pressing.

[0055] The low-density structured material can be honeycomb-type or foam-type.

[0056] The step of baking said veneer 14 with the adhesive film 15 is carried out at a temperature between 110°C and 165°C, preferably between 110°C and 140°C, and lasts between 20 seconds and 30 minutes, preferably between 2 and 10 minutes.

[0057] In one embodiment, the step of baking said veneer 14 with said glue film 15 is carried out in a hot compression press under a pressure of between 12 and 25 bar.

[0058] The step of baking said veneer 14 and the adhesive film 15 on said at least one layer 13 of resin pre-impregnated material is carried out at a temperature between 100°C and 150°C, preferably between 125°C and 135°C and lasts between 20 and 360 minutes, preferably between 90 and 120 minutes.

[0059] This cooking step is carried out either in a hot compression press under a pressure of between 0.3 and 5 bar, or in an oven, or even in an autoclave.

[0060] Veneer 14 is made of wood with a thickness of a few tenths of a millimeter, preferably between 0.4 mm and 1 mm.

[0061] In one embodiment, between said plating 14 and said layer 13 of pre-impregnated material is interposed an aluminum film 16 with a thickness of a few tenths of a millimeter, preferably between 0.05 mm and 0.2 mm.

[0062] In an advantageous embodiment, said method further comprises a step of adding a flame-retardant impregnating agent 17.

[0063] Layer 13 of prepreg material is composed of either fabrics or unidirectional webs.

[0064] Layer 13 of prepreg material is composed of fibers of the following group: glass, hybrids, carbon, aramid, linen, bamboo and hemp.

[0065] The present invention relates to a composite panel 10, in particular intended for aircraft or nautical furniture, for example obtained by implementing the method mentioned above, said composite panel 10 comprising a central core 11 formed from a core 12 of low-density structured material type coated on both sides with at least one layer 13 of resin-prepreg material, at least one of the sides of said panel 10 being covered with a veneer 14.

[0066] The composite panel 10 is either flat or shaped.

[0067] The invention is described in the foregoing by way of example. It is understood that a person skilled in the art is able to carry out different variants of the invention without departing from the scope of the patent.

Claims

1. Composite panel (10), in particular intended for aircraft or nautical furniture, including a central core (11) formed from a core (12) of a low-density structured material type covered on each of its two faces with at least one layer (13) of material impregnated with resin, at least one of the faces of said panel (10) being covered with a veneer (14), characterised in that a film (15) of glue is glued on one of the faces of said veneer (14) and on said at least one layer (13) of material pre-impregnated with resin.

2. Composite panel (10), in particular intended for aircraft or nautical furniture, according to claim 1, characterised in that it is flat.

3. Composite panel (10), in particular intended for aircraft or nautical furniture, according to claim 1, characterised in that it is in shape.

4. Composite panel (10), in particular intended for aircraft or nautical furniture, according to one of the preceding claims, characterised in that, between said veneer (14) and said layer (13) of preimpregnated material, a film of aluminium (16) with a thickness of a few tens of millimetres is interposed.

5. Composite panel (10), in particular intended for aircraft or nautical furniture, according to claim 4, characterised in that said film of aluminium (16) has a thickness of between 0.05 mm and 0.2 mm.

6. Composite panel (10), in particular intended for aircraft or nautical furniture, according to one of claims 4 or 5, characterised in that the aluminium is added between two films of glue.

7. Composite panel (10), in particular intended for aircraft or nautical furniture, according to one of the preceding claims, characterised in that said low-density structured material (12) is of the honeycomb type.

8. Composite panel (10), in particular intended for aircraft or nautical furniture, according to one of claims 1 to 6, characterised in that said low-density structured material (12) is of the foam type.

9. Composite panel (10), in particular intended for aircraft or nautical furniture, according to one of the preceding claims, characterised in that said layer (13) of preimpregnated material is composed of fabrics.

10. Composite panel (10), in particular intended for aircraft or nautical furniture, according to one of claims 1 to 8, characterised in that layer (13) of preimpregnated material is composed of unidirectional sheets.

11. Composite panel (10), in particular intended for aircraft or nautical furniture, according to one of claims 1 to 10, characterised in that said layer (13) of preimpregnated material is composed of fibres of a type in the following group: glass, hybrids, carbon, aramid, linen, bamboo and hemp.

12. Composite panel (10), in particular intended for aircraft or nautical furniture, according to one of the preceding claims, characterised in that it furthermore includes a flame-retarding impregnating agent (17).