| 摘要 |
A polyvinylbutyral moulding is produced by extruding a moulding composition containing polyvinylbutyral, plasticiser, a phenolic stabiliser and a triester of phosphorous acid. Before or during the extrusion, A) 0.05 - 0.5% by weight of the phenolic stabiliser and B) 0.02 - 0.5% by weight of a phosphorous acid triester which is nonvolatile during processing, are added to the polymer and/or the plasticiser, the sum A + B being </= 0.6% by weight, and the A:B ratio being between 90:10 and 20:80. In spite of the low phosphite concentration, the effect of colour lightening or reduction in discolouration in extruded mouldings, for example sheeting, is very clear even at extrusion temperatures of 200 DEG C or more. |
