WO1990001090A1

WO1990001090A1 - Method for the manufacture of curved ceiling panels as well as a ceiling panel manufactured thereby

Info

Publication number: WO1990001090A1
Application number: PCT/DK1989/000181
Authority: WO
Inventors: Garn Claus Bugge; Praefke Palle Gottlieb
Original assignee: Rockwool International AS
Current assignee: Rockwool AS
Priority date: 1988-07-25
Filing date: 1989-07-21
Publication date: 1990-02-08
Anticipated expiration: 1991-01-25
Also published as: DK415888D0; DK159564C; DK415888A; DK159564B

Abstract

Method for the manufacture of curved ceiling panels comprising a carrier layer in the shape of a sheet of mineral wool containing a binder and having a painted surface and/or a surface coated with woven or unwoven textile or a foil, which surface is suited for being used as ceiling surface in a room. In order to be able, at comparatively low cost, to manufacture cured ceiling panels having the same surface structure as corresponding plane panels and by use of a simple mould corresponding to one of the surfaces of the ceiling panel, the method is characteristic in that ceiling panel is split into a number of layers by means of at least one incision running parallel to the coated surface, and in that the ceiling panel is rebuilt on a female mould having the desired curvature, a curable adhesive being placed between the layers.

Description

METHOD FOR THE MANUFACTURE OF CURVED CEILING PANELS AS WELL AS A CEILING PANEL MANUFACTURED THEREBY

The present invention relates to a method for the manufacture of curved ceiling panels comprising a carrier layer in the shape of a sheet of mineral wool containing a binder and having a painted surface and/or a surface coated with woven or unwoven textile or a foil, which surface is suited for being used as ceiling surface in a room. Moreover, the invention relates to a ceiling panel manufactured by this method.

From the specification to US Patent No. 3,959,572 a method is known for the manufacture of mineral wool sheets, which deviate from plane form and which have been, provided with a painted or otherwise coated surface. According to this known method, the sheet acquires it final shape in a press between two portions of a two-piece mould. It has turned out that if the mineral wool before the moulding is provided with a layer of unwoven, resilient material, and if the moulding takes place before the binder in the mineral wool is cured, it will be possible during the pressing to give the sheet even rather complicated shapes, and during this process to stretch the mineral wool evenly, so that the subsequent treatment of the surface can take place with a fairly homogenous result all over the surface of the sheet. If is often desirable to produce curved panels which may bridge different levels of a larger ceiling. At the same time there is a strong desire that the surface forming the ceiling of the room is to have exactly the same colour and structure both with respect to the curved panels as to the remaining panels of the ceiling. Such a homogenity cannot be achieved with certainty with the known method, among others because the press-moulded panels cannot be cured in the same oven as the one used for the plane panels. Another disadvantage in the known method is the considerable costs involved in producing the two-piece mould. The object of the present invention is to provide a method, by means of which it is possible at fairly low costs to produce curved ceiling panels having the same surface structure as corresponding plane panels and with the use of a simple form corresponding to one of the surfaces of the ceiling panel.

This object is achieved according to the invention by means of a method of the kind described by way of introduction, said method being characteristic by the subject matter stated in the characterizing clause of claim 1.

By splitting the carrier layer of the ceiling panel, the rigidity of the panel is reduced to such an extent that when put into the female mould, it will follow its profile. It is therefore possible to take out some panels manufactured in the same series as the remaining panels to be delivered at the same time, split them and rebuild them in the desired curved shape, the layers of adhesive giving the panels their original self-carrying properties and moreover having the a reinforcing effect, thus adding to their rigidity.

As the surface to form the ceiling in the room is untouched during the process, the curved panel will get the completely same colour and structure as the remaining panels of the same series, from which it was taken out. As a simple, one-piece mould is used, the costs involved are low. Preferred embodiments are disclosed in claims 2-6. Moreover, the invention relates to a ceiling panel of the type manufactured by the method according to the invention. The ceiling panel is characterized by the subject matter of the characterizing clause of claim 6. As the layers of adhesive are absorbed in the adjacent layers of mineral wool, the rebuilt panel gets a rigidity, which is at least equal to the rigidity of the panel used as a starting material, even if only one layer of adhesive placed near the neutral plane of the panel is used. As the adhesive can only be absorbed in the immediately adjacent layers, there is no risk of a complete*drenching and.subsequent discolouring of the surface coating.

The invention will be described in detail in the following with reference to the drawing, in which fig. 1 is a side-face of a ceiling panel, fig. 2 is a section through a part of a ceiling panel according to the invention and through a part of a suspension beam, fig. 3 is a section corresponding to fig. 2 through a ceiling panel split into three layers, and fig. 4 is an enlarged section through the ceiling panel according to fig. 2.

Greater ceiling areas, which are provided with ceiling panels, may in certain cases be of different levels. There is, therefore, a need for ceiling panels, which in an even curvature may bridge the two levels. Such a ceiling panel may have a profile seen from the side-face corresponding to the ceiling panel shown in fig. 1. The ceiling panel is manufactured by providing a carrier layer of mineral wool at the surface to form the ceiling of the room with a surface coating, which can be a paint and/or a woven or unwoven textile or possible a perforated foil. The carrier layer of mineral wool has such a thickness and such a content of binder, which binds the fibres at their intersecting points, that the carrier layer without any excessive bending is self-supporting when placed between the flanges 2 of the two suspension beams (figs. 2 and 3). By the method according to the invention it is possible from a plane ceiling panel having the desired surface colour and structure to manufacture a profiled, curved ceiling panel. The ceiling panel is split by means of at least one incision running preferably in parallel with the coated surface, into at least two layers, the rigidity of which has been reduced to such an extent that they are no longer self-supporting, but flexible in a one-piece mould corresponding to the profile of the curved panel ceiling to be manufactured. At first preferably the layer, which is at one side provided with the surface layer, is placed against the mould. Then an adhesive is applied to the next layer of the side to face the first layer, said adhesive being sufficiently fluent to penetrate into the part of the mineral wool closest to the incision edge but being on the other hand so viscious or thixotropic that it is not fully absorbed by the mineral wool, which could make it penetrate the whole layer and discolour the surface to form the ceiling after the mounting of the ^'panel. When the panel has been rebuilt from the two or more layers, into which it was split, the adhesive is allowed to cure, after which the panel is then ready and has been given the desired profile. The ceiling panel 1 shown in fig. 2 has been split into two^, layers of approximately the same thickness. They have been rejoined by means of a layer 3 of adhesive after having been placed on a mould in the shape of a sheet, which seen from a side edge may have the same shape as the sheet shown in fig. 1. After the curing of the binder, the panel 1 will have acquired the same profil as the sheet shown in fig. 1.

Fig. 3 shows a sheet 1, which apart from having been spilt by two incisions, corresponds to the sheet according to fig. 2. In order to increase the rigidity of the rebuilt sheet, which by the incision has been reduced in thickness by the width of the incisions made, it may be advantageous to embed in the layers of adhesive a fleece, for instance of glass fibres. This fleece may be used for appplication of the adhesive, the adhesive being according to its consistency either poured out or applied as a filler onto the fleece or the fleece may be dipped into the adhesive before being replaced during the rebuilding of the ceiling panel. Fig. 4 is a section through a ceiling panel consisting of two layers, in which it is seen that an absorption of the adhesive in the parts of the split mineral wool adjacent to the incision is aimed at.

As starting material for the manufacture of celing panels it is costumary to use a mineral wool having a specific weight of 60-80 kg/m and a content of binder of 2- 3 per cent. The binder is normally a phenolformaldehyde binder. As adhesive a PU-glue of a type foaming after application may be used, a fair certainty of the glue joint being completely filled being thus attained. As an example of such a glue Sadofoss 3930 can be mentioned. This glue has a curing time of approx. half an hour at 20°C, which does to a fair extent secure an effective production and an adequately long "open" time for the rebuilding of the panels. The adhesive may be applied as a uniform layer or in the shape of stripes being placed in parallel and with such a distance that they tend to unite when the layers are joined. Two mutually intersecting rows of stripes may be applied to the sheets, in which case the stripes may have a somewhat bigger mutual distance.

Claims

C l a i s

1. Method for the manufacture of curved ceiling panels comprising a carrier layer in the shape of a sheet of mineral wool containing a binder and having a painted surface and/or a surface coated with woven or unwoven textile or a foil, which surface is suited for being used as ceiling surface in a room, c h a r a c t e r i z e d in that

- the ceiling panel is split into a number of layers by means of at least one incision running parallel to the coated surface, and

- in that the ceiling panel is rebuilt on a female mould having the desired curvature, a curable adhesive being placed between the layers.

2. Method according to claim 1, c h a r a c t e r¬ i z e d in that the coated surface faces the female mould.

3. Method according to claims 1 or 2, c h a r a c t- e r i z e d in that a fleece, for instance a glass fleece, is inserted between the layers.

4. Method according to claim 3, c h a r a c t e r¬ i z e d in that the adhesive is applied to the layers by means of the fleece.

5. Method according to claims 1, 2, 3, or 4, c h a¬ r a c t e r i z e d lin that the adhesive is a partly foaming PU-binder which cures in the open.

6. Method according to any of the claims 1-5, c h a¬ r a c t e r i z e d in that the adhesive is applied in the shape of one or more stripes that may cross one another.

7. Ceiling panel comprising a carrier layer of a mineral wool sheet containing a binder having a painted surface and/or a surface coated with vowen or unvowen textile or a foil suited for being used as ceiling surface in a room, c h a r a c t e r i z e d in that the ceiling panel parallel to the ceiling surface comprises one or more layers of a cured adhesive preferably dividing the thickness of the ceiling panel into equally big parts, and which has been partly absorbed, in an adjacent layer of the mineral wool.

8. Ceiling panel according to claim 3, c h a r a c t¬ e r i z e d in that the thickness of the adjacent layer is 0.5 - 3 mm.

9. Ceiling panel according to claims 7 or 8, c h a- r a c t e r i z e d in that in the layer of cured adhesive a fleece, preferably a glass fleece, has been embedded.