Manufacture of polarizing films
AssigneeAgfa-Gevaert
InventorKarl-Heinz A. O. Starzewski
Life of this patent
Estimating the term…
Abstract
The process for manufacturing a polarizing film based on polyvinyl alcohol and at least one dichroic substance by casting or extrusion of a mixture of polyvinyl alcohol and a solvent, whereby the polyvinyl alcohol contains the dichroic substance, drying and stretching of the film by between 300 and 1200%, whereby, depending on the width of the unstretched film b.sub.o, a stretch gap l.sub.o is provided, satisfying the condition b.sub.o /l.sub.o <3, leads to higher dichroic extinction quotients.
Claims8
Process for manufacturing a polarizing film based on polyvinyl alcohol and at least one dichroic substance by casting or extrusion of a mixture or polyvinyl alcohol and a solvent, whereby the polyvinyl alcohol contains the dichroic substance, drying and stretching of the film at between 10.degree. and 210.degree. C. by 300 to 1200%, wherein, depending on the width of the unstretched film b.sub.o a stretch gap 1.sub.o is provided, satisfying the condition b.sub.o /l.sub.o <3.
Process for manufacturing a polarizing film based on polyvinyl alcohol and polyacetylene by casting or extrusion of a mixture of polyvinyl alcohol and a solvent, whereby the polyvinyl alcohol contains the polyacetylene, drying and stretching of the film at between 10.degree. and 210.degree. C. by 300 to 1200%, wherein, depending on the width of the unstretched film b.sub.o, a stretch ga l.sub.o is provided, satisfying the condition b.sub.o /l.sub.o <3.
Dependencies are inferred from the claim text.