Construction material
A construction material comprises a watertight sheet material of a mixture of a plastic and at least one additive. The plastic comprises at least substantially polyvinyl butyral (PVB). At least a fire retardant containing ammonium polyphosphate is added thereto as additive. Use is particularly made of recycled polyvinyl butyral.
1 . A roof covering, comprising a watertight sheet material from at least a plastic and at least one additive, characterized in that the plastic comprises at least substantially polyvinyl butyral (PVB), wherein the at least one additive comprises at least a fire retardant containing ammonium polyphosphate (NH 4 PO 3 ) n (APP) and aluminum trihydrate (Al(OH) 3 ) (ATH):
wherein the polyvinyl butyral (PVB) and the ammonium polyphosphate (NH 4 PO 3 ) n (APP) are used in the mixture in a weight ratio of about 100:4-50; and
wherein the polyvinyl butyral (PVB) and the aluminum trihydrate (ATH) are used in the mixture in a weight ratio of about 100:40-50.
2 . The roof covering of claim 1 , characterized in that the at least one additive in the mixture also comprises a coloring agent.
3 . The roof covering of claim 2 , characterized in that a white pigment, comprising titanium oxide and/or titanium dioxide, is used as the coloring agent.
4 . The roof covering of claim 1 , characterized in that the at least one additive in the mixture comprises one or more selected from the group consisting of a UV stabilizer and an antioxidant.
5 . The roof covering of claim 1 , characterized in that the at least one additive in the mixture comprises at least a plasticizer.
6 . The roof covering of claim 5 , wherein the plasticizer comprises an ethylene/vinyl acetate/carbon monoxide copolymer.
7 . The roof covering of claim 1 , characterized in that the sheet material has a thickness of half a millimeter to several millimeters, by a width of half a meter to several meters, and is wound into a roll with a length of several meters or several tens of meters to over a hundred meters.
8 . The roof covering of claim 1 , wherein the polyvinyl butyral is recycled polyvinyl butyral.
9 . The roof covering of claim 1 , wherein the aluminum trihydrate is in the form of particles with an average particle size smaller than 100 microns.
10 . The roof covering of claim 7 , wherein the sheet material has a thickness of between 0.6 and 5 millimeters.
11 . The roof covering of claim 1 , wherein the polyvinyl butyral, aluminum trihydrate and ammonium polyphosphate are applied in a ratio of about 2:1:1.
12 . The roof covering of claim 1 , wherein the polyvinyl butyral (PVB), aluminum trihydrate (ATH) and ammonium polyphosphate (APP) are applied in a ratio of 100 PVB:40 ATH:4 APP.