摘要:
An electrophotographic element comprises: an electrically conducting layer, a charge generating layer overlying the electrically conducting layer, and a charge transport layer overlying the electrically conducting layer. The charge transport layer, which can be an overcoat overlying the charge generating layer, comprises the reaction product in an aqueous medium of a mixture comprising a silsesquioxane polymer and a hole transport compound that comprises a tertiary arylamine containing at least one alcoholic or one phenolic hydroxy substituent.
摘要:
An electrophotographic element comprises: an electrically conducting layer, a charge generating layer overlying the electrically conducting layer, and a charge transport layer overlying the electrically conducting layer. The charge transport layer, which can be an overcoat overlying the charge generating layer, comprises the reaction product in an aqueous medium of a mixture comprising a silsesquioxane polymer and a hole transport compound that comprises a tertiary arylamine containing at least one alcoholic or one phenolic hydroxy substituent.
摘要:
Disclosed are photoconductive elements including a conductive support, e.g., an electrically conductive film, drum, or belt, on which a negatively chargeable photoconductive layer is disposed. An electrical barrier layer is disposed between the conductive support and the photoconductive layer. The barrier layer provides a high energy barrier to the injection of positive charges, but transports electrons under an applied electric field. In embodiments, the barrier layer can transport charge by electronic, or both electronic and ionic mechanisms, and, is not substantially affected by humidity changes. The barrier layer includes a polyester-co-imides, polyesterionomer-co-imides, or polyamide-co-imides having covalently bonded as repeat units in the polymer chain, aromatic tetracarbonylbisimide groups of the formula: or wherein Ar 1 and Ar 2 respectively represent tetravalent or trivalent aromatic groups of 6 to about 20 carbon atoms, and X is O, C(CF 3 ) 2 , S=O or SO 2 .
摘要:
In a photoconductive element comprising a conductive support, e.g., an electrically conductive film, drum or belt on which a negatively chargeable photoconductive layer is formed, an electrical barrier layer is formed between the support and the photoconductive layer. The barrier layer provides a high energy barrier to the injection of positive charges but transports electrons under an applied electric field. The barrier layer of the invention transports charge by electronic rather than ionic mechanisms and, therefore, is not substantially affected by humidity changes. The barrier layer comprises a polyester-co-imide, polyesterionomer-co-imide or polyamide-co-imide having covalently bonded as repeating units in the polymer chain, aromatic tetracarboxylbisimide groups of the formula:
wherein Ar 1 and Ar 2 represent, respectively, tetravalent and trivalent aromatic groups of 6 to 20 carbon atoms.
摘要:
A photoconductive sleeved primary image forming member roller for use in an electrophotographic machine comprising a central member including a rigid cylindrical core member and a compliant layer formed on the core member; and a flexible replaceable removable photoconductive sleeve member in the form of an endless tubular belt that surrounds and nonadhesively intimately contacts the central member.
摘要:
An amorphous mixture consisting essentially of TiOFPc and TiOPc and containing more than 75 weight percent of substantially chlorine-free TiOPc is produced by forming a mixture of crude crystalline TiOFPc and crude crystalline, substantially chlorine-free TiOPc that contains less than 80 weight percent TiOPc, treating the mixture under conditions effective to form a substantially amorphous mixture of TiOFPc and TiOPc containing less than 75 weight percent TiOPc, which is then treated with water, and dried. A further amount of crude crystalline, substantially chlorine-free TiOPc sufficient to form a new mixture containing more than 75 weight percent of substantially chlorine-free TiOPc is added, and the new mixture is converted to a substantially amorphous mixture of TiOFPc and TiOPc. A nanoparticulate cocrystalline composition is obtained by forming a slurry in an organic solvent of the dried substantially amorphous mixture, and wet milling the slurry to form the cocrystalline composition.
摘要:
In a process for forming an amorphous pigment mixture consisting essentially of TiOPc and TiOFPc and containing more than about 75 weight percent of TiOPc, a mixture of crude crystalline TiOPc and TiOFPc pigments in a weight ratio of at least 75:25 TiOPc: TiOFPc is combined with at least about 5 wt.%, based on the total weight of TiOPc and TiOFPc, of an organic milling aid. The mixture is treated under conditions effective to form a substantially amorphous pigment mixture of TiOPc and TiOFPc. The organic milling aid can be separated from the substantially amorphous pigment mixture, which can be converted to a nanoparticulate cocrystalline TiOPc/TiOFPc composition.
摘要:
In a process for forming an amorphous TiOPc/TiOFPc pigment mixture containing a low concentration of TiOFPc, a mixture containing phthalonitrile and titanium tetrachloride is subjected to reaction conditions effective to form lightly chlorine-substituted crude crystalline Cl-TiOPc. The lightly chlorine-substituted crude crystalline Cl-TiOPc is combined with crude crystalline TiOFPc in a weight ratio from about 75:25 Cl-TiOPc:TiOFPc to about 99.5:0.5 Cl-TiOPc:TiOFPC to form a crude crystalline pigment mixture, which is treated under conditions effective to form a substantially amorphous pigment mixture of Cl-TiOPc and TiOFPc. The substantially amorphous mixture can subsequently be converted to a nanocrystalline Cl-TiOPc/TiOFPc pigment composition containing a low concentration of TiOFPc.
摘要:
In a process for forming a self-dispersing crystalline phthalocyanine pigment composition of monodisperse nanoparticles, a mixture containing titanyl fluorophthalocyanines, unsubstituted titanyl phthalocyanine, and an organic monomeric dispersant but substantially free of organic solvents or inorganic salts is dry milled, thereby forming a substantially amorphous phthalocyanine pigment composition. The substantially amorphous composition is contacted with an organic solvent having a hydrogen bonding parameter gamma c lower than about 8, thereby forming a self-dispersing cocrystalline phthalocyanine pigment composition of monodisperse nanoparticles containing titanyl fluorophthalocyanines and titanyl phthalocyanine, which can be used to form the charge generation layer of an electrophotographic element.
摘要:
In a process for forming a nanoparticulate crystalline titanium phthalocyanine pigment composition, a titanium phthalocyanine pigment is contacted with substantially pure 1,1, 2-trichloroethane (TCE) under conditions effective to convert the titanium phthalocyanine pigment to the nanoparticulate crystalline composition.