GB1562727A - Sheet metal panel for building purposes - Google Patents

Description

(54) A SHEET METAL PANEL FOR BUILDING PURPOSES (71) We, VAW LEICHTMETALL GMBH, a body corporate organized under the laws of the German Federal Republic, of 5300 Bonn, Dellweg 1, German Federal Republic, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a sheet metal panel for building purposes.

Conventional sheet metal roofings and wall coverings combine with their well known advantages, the drawbacks of being responsive to vibratory effects and of generating resonant drone. They also have the drawback of attracting condensation.

Constructional steps that can be taken to suppress noise, to avoid condensation and to ensure that they can be fixed in a manner that does not allow them to vibrate are all expensive and sometimes they can be employed only to a limited extent, if at all.

In order to overcome this difficulty, it has been proposed in German Patent Specification No. 587,777 to apply a single-layer metal covering for roofs and walls to a fixed base by directly sticking down a thin corrosion-resistant metal sheeting that can be rolled, drawn and hammered directly on the base with a non-hardening softish bonding mass, such as asphalt or a like substance. However, it is not possible to use such a sheet in the absence of a suitable support for the sheet, particularly when the sheet is attached to an underframe which leaves it otherwise unsupported.

Accoustically every sheet material consisting of resilient springy metal is liable to generate drone, i.e. when tapped it may begin to vibrate, even light tans causing the build-up of an obiectionabe amount of reverberant noise. In practice, noise of this kind can be caused by rain, wind, or even by movement of one metal sheet in relation to another or to its fastening and the structure underneath.

For the purpose of su pressing such effects, sheet metal panels osuch a kind are frequently provided with an anti-drone lining. Such linings may consist, for instance, of bituminous compounds, but in building practice these constitute an undesirable fire risk. Backings and linings containing synthetic plastics and plastics foams have also been proposed, but these similarly increase the fire risk, and some of- them even promote corrosion because water vapour may penetrate foams and condense, and if the condensate advances as far as the metal, the latter may suffer damage or the bond may be impaired. Such plastics linings also call for a considerable capital expenditure anchor they raise costs.

Combinations of such metal sheets with mineral panels or the application of selfadhering mineral compositions have also been proposed. Besides even higher cost, the corrosive effects, like those mentioned in connection with plastics, are also objectionable.

Attempts have further been made to reduce drone by sticking together metal sheets of approximately the same thickness.

However, the bond between metal sheets that have been thus stuck together cannot be sufficiently precisely controlled with respect to the static load the compound sheet can carry to permit the entire resultant thickness to be utilised. Moreover, fabrication is also expensive and calls for considerable investment cost. Altogether the proposal is uneconomical and has not found acceptance in practice.

It is an object of the present invention to provide a sheet metal panel for building purposes which provides optimum damping and noise attenuation whilst at the same time permitting the static bearing potential of the entire sheet metal thickness to be fully utilised.

According to the present invention there is provided a sheet metal panel for building purposes, wherein a resilient metal sheet of 0.5 to 2.0 mm. gauge is adhesively bonded to a metal foil 50 to 200 microns thick using a bonding layer of a polymeric adhesive comprising ethylene as a polymeric constituent and applied at the rate of 20 to 80 g./sq.m.

The metal sheet and metal foil may be of aluminium or an aluminium alloy and the foil is preferably aluminium foil.

The present sheet metal panel for building purposes not only overcomes the drawbacks of the sheet metal panels hitherto used for roofings and wall coverings, it also has the advantage of providing a considerable saving in material and weight without its contemplated use being thereby impaired in any way.

Moreover, the thin strip material can be handled in industrial plant in which plastics foil of the same thickness is normally used for lining metal strip.

The present sheet metal building panels can in practice be treated like ordinary sheet metal panels, i.e. they can be trimmed, beaded, and corrugated. They can be delivered to a building site in the form of flat sheets cut to any desired shape, or in performed or pretreated form. Visually their appearance is equal to that of a building panel made of normal sheet metal, and their static properties are not less than those of a single layer sheet metal.

Various methods of pretreating the foil as well as of the metal sheet can be used.

Moreover, various adhesion aids or bonding agents can be used. It is further possible to prime the sheet metal to improve adhesion.

The strength of the adhesive bond of the lining depends upon the surface of the metal strip and presents no problems in the case of for instance lacquered strip because sufficient bonding strength is then always achieved, In the case of bright aluminium strip a surface treatment can be dispensed with although degreasing is usually necessary to ensure adhesion.

The invention will now be illustrated by the following Example.

A sheet metal building panel is obtained by degreasing an aluminium sheet of I mm.

gauge and lining the same on one side with a degreased 150 micron gauge aluminium strip, using 50 g./sq.m. of an ethylene copolymer as the adhesive. The resultant sheet metal panel has excellent noise suppression properties. The static properties of the 1 mm. sheet are fully retained. Production is very inexpensive in view of the thinness of the lining.

WHAT WE CLAIM IS: 1. A sheet metal panel for building purposes, wherein a resilient metal sheet of 0.5 to 2.0 mm. gauge is adhesively bonded to a metal foil 50 to 200 microns thick using a bonding layer of a polymeric adhesive comprising ethylene as a polymeric constituent and applied at the rate of 20 to 80 g./sq.m.

2. A sheet metal panel as claimed in claim 1, wherein the metal foil is aluminium foil.

3. A sheet metal panel substantially has herein before described in the foregoing Example.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. a metal foil 50 to 200 microns thick using a bonding layer of a polymeric adhesive comprising ethylene as a polymeric constituent and applied at the rate of 20 to 80 g./sq.m. The metal sheet and metal foil may be of aluminium or an aluminium alloy and the foil is preferably aluminium foil. The present sheet metal panel for building purposes not only overcomes the drawbacks of the sheet metal panels hitherto used for roofings and wall coverings, it also has the advantage of providing a considerable saving in material and weight without its contemplated use being thereby impaired in any way. Moreover, the thin strip material can be handled in industrial plant in which plastics foil of the same thickness is normally used for lining metal strip. The present sheet metal building panels can in practice be treated like ordinary sheet metal panels, i.e. they can be trimmed, beaded, and corrugated. They can be delivered to a building site in the form of flat sheets cut to any desired shape, or in performed or pretreated form. Visually their appearance is equal to that of a building panel made of normal sheet metal, and their static properties are not less than those of a single layer sheet metal. Various methods of pretreating the foil as well as of the metal sheet can be used. Moreover, various adhesion aids or bonding agents can be used. It is further possible to prime the sheet metal to improve adhesion. The strength of the adhesive bond of the lining depends upon the surface of the metal strip and presents no problems in the case of for instance lacquered strip because sufficient bonding strength is then always achieved, In the case of bright aluminium strip a surface treatment can be dispensed with although degreasing is usually necessary to ensure adhesion. The invention will now be illustrated by the following Example. A sheet metal building panel is obtained by degreasing an aluminium sheet of I mm. gauge and lining the same on one side with a degreased 150 micron gauge aluminium strip, using 50 g./sq.m. of an ethylene copolymer as the adhesive. The resultant sheet metal panel has excellent noise suppression properties. The static properties of the 1 mm. sheet are fully retained. Production is very inexpensive in view of the thinness of the lining. WHAT WE CLAIM IS:

1. A sheet metal panel for building purposes, wherein a resilient metal sheet of 0.5 to 2.0 mm. gauge is adhesively bonded to a metal foil 50 to 200 microns thick using a bonding layer of a polymeric adhesive comprising ethylene as a polymeric constituent and applied at the rate of 20 to 80 g./sq.m.

2. A sheet metal panel as claimed in claim 1, wherein the metal foil is aluminium foil.

3. A sheet metal panel substantially has herein before described in the foregoing Example.