73results about "Pigment preparation by PVD/CVD methods" patented technology

A color shifting multilayer interference film is provided which may be used to produce flakes for use in colorants having color shifting properties. The flakes can be interspersed into liquid media such as paints or inks which can subsequently be applied to objects or papers to achieve color variations upon shifts in angle of incident light or upon shifts in viewing angle. A five layer design of the interference film includes a first absorber layer, a first dielectric layer on the first absorber layer, a reflector layer on the first dielectric layer, a second dielectric layer on the reflector layer, and a second absorber layer on the second dielectric layer. A three layer design of the interference film includes first and second absorber layers with a dielectric layer therebetween. The dielectric layers are formed to have an optical thickness at a design wavelength that provides a color shift as the angle of incident light or viewing changes.

Interference pigment flakes and foils are provided which have color shifting properties. The pigment flakes can have a symmetrical coating structure on opposing sides of a reflector layer, can have an asymmetrical coating structure with all of the layers on one side of the reflector layer, or can be formed with encapsulating coatings around a core reflector layer. The coating structure of the flakes and foils includes a reflector layer, a dielectric layer on the reflector layer, and a titanium-containing absorber layer on the dielectric layer. The pigment flakes and foils exhibit a discrete color shift so as to have a first color at a first angle of incident light or viewing and a second color different from the first color at a second angle of incident light or viewing. The pigment flakes can be interspersed into liquid media such as paints or inks to produce colorant compositions for subsequent application to objects or papers. The foils can be laminated to various objects or can be formed on a carrier substrate.

A process for making functional or decorative flakes or platelets economically and at high production rates comprises applying a multi-layer sandwich of vapor deposited metal and release coats in alternating layers to a rotating chilled drum or suitable carrier medium contained in a vapor deposition chamber. The alternating metallized layers are applied by vapor deposition and the intervening release layers are preferably solvent soluble thermoplastic polymeric materials applied by vapor deposition sources contained in the vapor deposition chamber. The multi-layer sandwich built up in the vacuum chamber is removed from the drum or carrier and treated with a suitable organic solvent to dissolve the release coating from the metal in a stripping process that leaves the metal flakes essentially release coat free. The solvent and dissolved release material are then removed by centrifuging to produce a cake of concentrated flakes which can be air milled and let down in a preferred vehicle and further sized and homogenized for final use in inks, paints or coatings. In one embodiment the finished flakes comprise single-layer thin metal or metal alloy flakes or flakes of inorganic materials, and in another embodiment flakes are coated on both sides with protective polymeric coatings that were applied from suitable vacuum deposition sources or the like contained in the vapor deposition chamber.