Patent ID: 7532389

Claim:
An electrophoretic display comprising: a) two electrode plates; b) an array of display cells filled with an electrophoretic fluid comprising charged pigment particles dispersed in a fluorinated solvent or solvent mixture wherein the fluorinated solvent or solvent mixture is colored by a fluorinated silicon phthalocyanine or silicon naphthalocyanine compound represented by the following formulas: wherein each n is individually 0-4 for silicon phthalocyanine (I) or 0-6 for silicon naphthalocyanine (II); R 1 is independently R f -A-, alkyl, heteroalkyl, aryl, heteroaryl, heteroalkylaryl, alkylheteroaryl, heteroarylalkyl, arylheteroalkyl, R′O—, R′S—, R′R″N—, R′CO—, R′OCO—, R′COO—, R′CONR″—, R′R″NCO—, R′NHCONR″—, R′SO 2 NR″—, or R′R″NSO 2 —; or a halogenated derivative of alkyl, heteroalkyl, aryl, heteroaryl, heteroalkylaryl, alkylheteroaryl, heteroarylalkyl, arylheteroalkyl, R′O—, R′S—, R′R″N—, R′CO—, R′OCO—, R′COO—, R′CONR″—, R′R″NCO—, R′NHCONR″—, R′SO 2 NR′—, or R′R″NSO 2 —; wherein R′ and R″ are independently hydrogen, R f , alkyl, heteroalkyl, aryl, heteroaryl, heterarylalkyl, arylheteralkyl, heteroalkylaryl, or alkylheteroaryl; A is a single bond, —CH 2 O—, —CH 2 CH 2 O—, or —CO—; Z is O or NR′ wherein R′ is defined as above; R 2 is hydrogen, R f —B—, alkyl, heteroalkyl, a halogenated derivative of alkyl, a halogenated derivative of heteroalkyl, or SiR 3 R 4 R 5 , wherein R 3 , R 4 , and R 5 are independently an alkyl or fluoroalkyl group of 1 to 20 carbon atoms or alkoxy or fluoralkoxy of 2 to 40 carbon atoms; B is a single bond, —CH 2 —, or —CH 2 CH 2 —; R f is a fluorinated polymeric or oligomeric moiety having a molecular weight of 100-100,000 and is prepared from one or more types of fluorinated monomers; provided that the substituents, R 1 , R 2 , R 3 , R 4 , R 5 , R f , Z and n are so selected that the total fluorine content of the fluorinated silicon phthalocyanine or silicon napthalocyanine compound is at least 20% by weight, and said charged pigment particles in the electrophoretic fluid are capable of moving towards one or the other electrode plate depending on the voltage difference imposed between the two electrode plates.