DETAILED DESCRIPTION OF THE INVENTION It has now been determined according to this invention that markedly improved organic pigment lakes are prepared by adsorption of virtually the broad spectrum of the high molecular weight or polymeric dyestuffs onto the various, art recognized substrata or extenders therefor.
Such polymeric dyes, as shall later be fully representatively illustrated, will hereinafter and in the claims be designated the dye component of the subject, improved organic pigment lakes.
These dyes are not composed exclusively of pure chromophore.
Rather, the polymeric dye is additionally comprised of certain non-chromophoric units, chemical groups, and/or molecular segments which function to bind the chromophoric groups into the unit high molecular weight or polymeric dye.
The Polymeric Dyes Representative dyes for use according to the invention include those having two distinct moieties; a first chromophore segment, indicated as Ch, which supplies the coloring effect; and a second non-chromophore segment (B) which links the said chromophores into a polymeric network.
Thus, these representative dyes exhibit the following structural formulae (I) and (II): ##STR2## wherein "n" is an integer greater than 1, such as from 2 to about 4,000, more especially 10 to about 3,000.
Although the average molecular weights which correspond to these values of n of course depend upon the "sizes" of B and Ch, it is generally preferred to employ polymeric dyes having molecular weights in the 1,000 to 2,000,000 range, so long as the requirement is met that a plurality of chromophores be present.
A monomeric dye meeting this molecular size would not be capable of providing the improved organic pigment lakes of the invention.
A most preferred molecular weight range is from about 5,000 to about 1,500,000, especially from 20,000 to 1,000,000.
While it will thus readily be appreciated that the precise chemical nature of any particular chromophore, Ch, is not a limitation upon the invention, and similarly with respect to any particular non-chromophore, B, there nevertheless remain certain technical restraints on the respective components
|
LCD 
