GB2344834A

GB2344834A - Composite panel

Info

Publication number: GB2344834A
Application number: GB9828079A
Authority: GB
Inventors: John P Russell
Original assignee: ISOWALL
Current assignee: ISOWALL
Priority date: 1998-12-18
Filing date: 1998-12-18
Publication date: 2000-06-21
Also published as: GB9828079D0

Abstract

A composite panel having an impermeable front face 11, a rear face 21, a core 12, and an impermeable edge strip 13, surrounding the core. The edge strip is impermeably sealed to the periphery of the front face of the composite panel and adapted to provide an inter-connecting, and impermeable, joint between adjacent composite panels. Said edge strip is manufactured from a high-density phenolic foam material, and the core is a mineral fibre having insulatory and fire resistant properties. The strip provides protection to the core from water vapour penetration, preventing unwanted precipitate or ice build up within the core in cold store applications. The faces 11 and 12 may be of galvanised or stainless steel or glass reinforced polyester.

Description

COMPOSITE PANEL The present invention relates to composite panels, and in particular, composite panels having a mineral fibre core which are suitable for use in low temperature applications.

Composite panels are well known for providing internal partition walls and suspended ceilings in building applications. Composite panels are also used in food production factories and cold or chill store buildings. However, due to fire risk and insurance requirements, there is an increasing need for noncombustible composite panels. Further, for low temperature store applications such as fill stores in which the temperature is maintained below O C, it has been found that ice can form within the core of a composite panel if an effective vapour seal is not provided to prevent this. Ice build up within the core of composite panels dramatically effects the thermal properties of the composite panel and also the structural strength of the composite panel will also be compromised.

In these low temperature applications, the composite panels are generally provided with an insulating core. Traditionally, the material used for the insulating core is either polystyrene, Styrofoam or polyurethane. These cores provide effective insulation for the composite panel and they maintain their thermal properties even at low temperatures. Further, they are less susceptible to ice formation since the materials are generally non-absorbent. However, the problem with these materials is that they are combustible, and therefore these panels will not provide protection against the spread of fires in buildings.

In order to provide protection against the spread of fires in buildings, mineral fibre has been found to be effective, since it is non-combustible. Accordingly, it is used in many applications for this purpose. Mineral fibre is also an effective insulating material. However, it is susceptible to water absorption and therefore, if not effectively sealed against water absorption, ice can build up on it in a low temperature environment.

When using composite panels, having mineral fibre provided as the core material, to construct internal partition walls or suspended ceilings, an effective inter-panel joint between adjacent panels is important in order to maintain impermeability of both the panels themselves and the internal partition walls or suspended ceilings as a whole. The impermeability of the edges of the panels has conventionally been provided by applying a vapour seal compound to the edge of each composite panel. However, if there is a breakdown of these seals, water vapour can penetrate into the mineral core. This will not only compromise the integrity of the composite panels, but also, in freezer applications, this water vapour will condense on the mineral fibres and can thereafter turn to ice.

Accordingly, it would be desirable to provide a new composite panel which is both suitable for use in low temperature applications and which also has a means for providing effective impermeability to joints between adjacent panels.

According to a first aspect of the present invention, there is provided a composite panel comprising a front impermeable face, a rear face, a core between the two faces, and an impermeable edge surrounding the core, the edge being impermeably sealed to at least part of the peripheral portion of the front face of the composite panel, wherein the impermeable edge is preferably in the form of at least one high density phenolic foam strip section and is adapted, in use, to provide an interdigiting joint with an adjacent composite panel. The impermeable edge may extend around the whole periphery of the panels, and the material of the faces may wrap at least partially around the edge. The core of the composite panel will usually be made from a mineral fibre. The impermeable strip provides protection to the core from vapour penetration and absorption, and more specifically, water vapour penetration or absorption, thereby preventing unwanted precipitate build up within the core of the composite panel. It should also be fire resistant Phenolic foam has much lower water absorption characteristics than mineral fibre and also superior fire resistance properties to that of commonly used plastic based insulation materials such as polystyrene, Styrofoam and polyurethane.

A typical mineral fibre is an insulation material which is made from molten nonorganic minerals, which are blown into a fibrous state. With the addition of binding elements these can be manufactured into a rigid slab, suitable for composite panels. The density of the material should be no less than about 80Kg/m3. Mineral fibres are also known as mineral wool, rock fibre, glass fibre and glass wool.

The composite panel may be produced by a method comprising the steps of providing a front impermeable face, a rear face, a core material and an impermeable edge, wherein the core material is sandwiched between the two faces and the edges are impermeably bonded to at least part of the peripheral portion of the front face of the panel, and a profile is cut into at least part of the edge to provide a means for interdigiting two adjacent edges together.

The impermeable front face is preferably manufactured from a sheet of metal, which may be hot dipped galvanise steel or stainless steel. Alternatively glass reinforced polyester, for example, could be used.

The peripheral portion of the sheet forming the face may be formed about at least part of the profile cut into the edge of the panel.

Preferred embodiments of the present invention are now described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a plan view of a composite panel in accordance with a preferred embodiment of the present invention ; Figure 2 is section A-A through the panel of Figure 1; Figures 3 and 4 are cut-away sections B-B and C-C through top and bottom edges of the composite panel of Figure 1; Figure 5 is a partial section of two adjacent edges of panels of the present invention in a non-linked position; Figure 6 is a partial section of the two edges of Figure 5 shown in an inter-linked and water impermeable position; and Figure 7 is an enlarged view corresponding to Figure 5 showing one particular panel construction in detail.

Referring now to Figures 1 and 2 there is shown a composite panel having front and rear faces 11,21 and a core 12. Around the peripheral portion of the panel 10 there are edge strips 13,23,33,43. These edge strips 13,23,33,43 are made from a phenolic foam bonded to an interior peripheral portion of front and rear faces 11,21. On the outer faces 14,15 of the edge strips 13,23 (Figures 5 and 6) defining side edges of the panel there are provided interdigiting profiles 16,18, the profiles 16,18 being shaped to be inter-connectable with opposing side edge strips provided on adjacent panels in order to provide a positive joint between two adjacent panels. Top and bottom edges 33,34 (Figures 3 and 4) have rectangular sections. This is because the composite panel shown of this embodiment is for a wall and the top and bottom edges 33,34 are fixed to a ceiling and a floor respectively. However, shaped profiles may be provided if required.

Referring now to Figures 5 and 6, the side edges 13,23 of the composite panel comprise high density phenolic foam strips. The interdigiting profiles 14,15 comprise milled grooves 18,20 and projections 16, 17 for engaging with corresponding projections 16 and grooves 18,20 milled into an adjacent edge strip on an adjacent panel. This interdigiting engagement provides an effective joint between adjacent panels.

A rounded cut-out or groove 19 is provided in the projections 17 of one of the profiles 15 so that upon interdigiting and compressing two edges together, a sealant or glue provided within the cut-out 19 forms a secure joint and an effective seal between the edges.

This embodiment shows the front and rear faces 11,21 extending over substantially the entire edge strips 14,15. This results in two joined panels having a minimum interference line visible when assemble in situ.

The front and rear faces 11,21 are preferably formed of hot dipped galvanised steel, stainless steel or glass reinforced polyester.

Referring now to figure 7, the front and rear faces or layers 11,21 are formed, at their peripheral portions, so as to wrap around an external comer region of the phenolic form edge 13,23, thus providing a reinforced edge to the corners of the panels. The face layers 11,21 also securely retain the edges 13,23 on the composite panels. The formed profiles of the edges 13,23 are such that the faces 11,21, when formed about the edges 13,23, sit in a rebated portion of the profile.

The shape of the edge regions of the faces 11,21, where they mate with the corners of the edges 13,23 may be achieved by roll forming.

The faces 11,21 of the panels, especially if they are formed of metal, provide a reflective surface to assist in maintaining low heat transmission through the panel and are secured to the remainder of the panels with a thick layer of glue 50.

The panel is preferably produced on a continuous laminating machine and its faces 11,21 are preferably formed of metal and which are bonded to the mineral fibre core and the phenolic foam edges with the glue 50. The panel passes through a series of roll formers, which form the edge detail on the metal face. A series of milling cutters form the profiles of the edges 13,23. The panel then exits the machine as a completed product.

The standard width of the panel is 1.20 m, however various widths are available. Thicknesses can vary from 25 mm up to 300 mm. The length of a panel is variable up to a maximum length of 20 m.

The design of the roll formed edge detail can also vary. For example, they may have simple tongue and grooved constructions, or simple stepped constructions, and the term"interdigiting"should be interpreted accordingly.

The present invention has been described above purely by way of example.

Modifications in detail may be made within the scope of the invention.

Claims

CLAIMS 1. A composite panel comprising a front impermeable face, a rear face, a core between the two faces, and an impermeable edge surrounding the core, the edge being sealed to at least part of the peripheral portion of the front face of the composite panel, wherein the impermeable edge is adapted, in use, to provide an interdigiting joint with an adjacent composite panel.
2. A composite panel according to claim 1, wherein the impermeable edge extends around the whole periphery of the panel.
3. A composite panel according to claim 1 or 2, wherein the impermeable edge is in the form of at least one high density phenolic foam strip.
4. A composite panel according to claim 1,2 or 3, wherein the core of the composite panel is made from a mineral fibre.
5. A composite panel according to any one of claims 1 to 4, wherein the front face extends substantially over the edge.
6. A composite panel according to any preceding claim, wherein at least part of the peripheral portion of one of the faces is formed about at least part of the edge.
7. A composite panel according to any one of the preceding claims, wherein at least part of the peripheral portion of one of the faces is formed about at least part of the profile of the edge to form an edge detail.
8. A composite panel according to anyone of claims 1 to 7, wherein the impermeable front face is manufactured from a metal.
9. A composite panel according to any of claims 1 to 7, wherein the impermeable front face is manufactured from a glass reinforced polyester.
10. A method according to any one of claims 1 to 9, wherein the edge is formed by milling the edge.
11. A composite panel substantially as hereinbefore described with reference to the accompanying drawings.