Abstract: A magnetic toner for developing electrostatic images, comprising at least a binder resin and a magnetic powder; the binder resin having 10 to 70 wt. % of a THF (tetrahydrofuran)-insoluble and a THF-soluble, the THF-soluble providing a molecular weight distribution in the chromatogram of GPC (gel permeation chromatography) thereof such that it provides a rate (Mw/Mn) of weight-average molecular weight (Mw)/number-average molecular weight (Mn).gtoreq.5, there are a peak in the molecular weight range of 2,000 to 10,000 and a peak or shoulder in the molecular weight range of 15,000 to 100,000 and a component having a molecular weight of 10,000 or smaller is contained in an amount of 10-50 wt. % based on the binder resin; the magnetic powder comprising spherical magnetic particles having a bulk density of 0.6 g/ml or larger.
Abstract: A carrier composition comprised of a core with a coating thereover comprised of a mixture of first and second polymers that are not in close proximity thereto in the triboelectric series.
Abstract: Disclosed is a carrier and developer composition, and a process for the preparation of carrier particles with substantially stable conductivity parameters which comprises (1) providing carrier cores and a polymer mixture; (2) dry mixing the cores and the polymer mixture; (3) heating the carrier core particles and polymer mixture, whereby the polymer mixture melts and fuses to the carrier core particles; and (4) thereafter cooling the resulting coated carrier particles.
Abstract: Electrostatic liquid developer having improved negative charging characteristics consisting essentially of(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in a major amount,(B) thermoplastic resin particles having an average by area particle size of less than 10 .mu.m,(C) charge director compound, and(D) at least one soluble solid or liquid organic monofunctional amine compound of the formula: R.sub.n NH.sub.3-n wherein R is alkyl, cycloalkyl or alkylene, or substituted alkyl, the alkyl, cycloalkyl, alkylene or substituted alkyl group being of 1 to 50 carbon atoms, and n is an integer of 1 to 3.Optionally, a colorant, e.g., a pigment; metallic soap, adjuvant can be present. The electrostatic liquid developer is useful in copying, making proofs including digital color proofs, lithographic printing plates, and resists.
Type:
Grant
Filed:
April 7, 1988
Date of Patent:
June 19, 1990
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
Lyla M. El-Sayed, James R. Larson, Torence J. Trout
Abstract: A developer for an electrostatic latent image is disclosed, which comprises a toner powder and a fine powder of an acrylic homopolymer or copolymer having an average particle size smaller than that of the toner powder. The developer can be easily cleaned off without causing damage to a latent image-forming member.
Abstract: A magenta toner is disclosed, which comprises a coloring composition comprising a thioindigo pigment, and a xanthene dye having general formula (I) or a laked xanthene dye thereof, and a binder resin: ##STR1## wherein R.sup.1, R.sup.2, R.sup.5, R.sup.6, and R.sup.7 each represent hydrogen or a lower alkyl group; R.sup.3 and R.sup.4 each represent a lower alkyl group; and A.sup.- represents halogen.
Abstract: An electrophotographic developer, such as a toner binder and a coating on a carrier, comprises a polyester having an acid value of 5 KOH mg/g or less and a hydroxyl value of 60 KOH mg/g or less, having a linear structure without crosslinking or a crosslinked structure provided by a monomer having three or more reactive groups. A toner having the polyester as a binder is effectively charged positively or negatively.
Abstract: An electrostatographic toner material suitably employable for a pressure fixing process, comprising a core material containing colorant and binder, and shell enclosing the core material, in which the binder comprises a polymer and a solvent having the boiling point of higher than 180.degree. C. and capable of dissolving or swelling said polymer.
Abstract: A toner for developing latent electrostatic images is disclosed which comprises a binder agent and .epsilon.-type copper phthalocyanine blue pigment which serves as coloring agent and positive polarity controlling agent.
Abstract: Disclosed is a toner powder for developing latent electrostatic images comprising as a binder for pigment material a block or graft copolymer composed of a crystalline polyester and an amorphous vinyl polymer. The amorphous vinyl polymer has at least two peaks in its molecular weight distribution curve. One is between 100,000 and 1,000,000 and another is between 2000 and 20,000.
Abstract: A photoconductor for electrophotography, including an electroconductive substrate; and a photosensitive layer formed on the electroconductive substrate and including a nobel azo compound or disazo compound as a charge generating substance. An azo compound is represented by the following general formula: ##STR1## wherein each of R.sub.1, R.sub.2, R.sub.3 and R.sub.4 stands for a hydrogen atom, a halogen atom, a hydroxy group, an alkyl group, an alkoxy group, an allyl group, an aryl group, an aralkyl group, a carboxyl group or an ester group, and C.sub.p stands for a residual group of a coupler.
Abstract: In a method of increasing the sensitivity of a photosensitive member for inputting digital light, the photosensitive member is prepared to have a steep variation in the value of .gamma. of a latent image formed on the photosensitive member. Digital light and another light are applied to the photosensitive member at substantially the same time. The other light is emitted by an incandescent light, a LED or a fluorescent lamp.
Abstract: A transdermal drug delivery system useful for the controlled, for example zero order release of one or more drugs to a selected skin area of a user, which system comprises an impervious backing sheet and a face membrane, the backing sheet and membrane secured together to form an intermediate reservoir. The face membrane is a macroporous membrane which has pores of sufficient size to avoid any rate control of the drug to be transdermally delivered to the user. The reservoir contains a viscous liquid base material selected to exude from the membrane to form a film and to occlude the skin of the user to force hydration of the stratum corneum with water from the lower layers of the epidermis of the user and a plurality of solid microparticles generally uniformly dispersed and suspended in the liquid base material. The microparticles containing an effective therapeutic amount of the drug for transdermal delivery, such as the contraceptive steroid.
Abstract: The disclosure describes carrier particles for use in a two-component dry-type developer, consisting of core particles which are coated with a silicone resin hardened by an organic tin catalyst.
Abstract: An electrophotographic photoconductor is disclosed which comprises an electroconductive support and a photoconductive layer formed thereon, which photoconductive layer comprises as a charge generating material an azo pigment having general formula (I): ##STR1## wherein R.sup.1, R.sup.2, X, A and n are respectively defined in the specification.
Abstract: An electrophotographic photoreceptor useful for negative electrification is disclosed. The photoreceptor comprises on an electroconductive substrate, a photo-sensitive layer containing a compound represented by general formula [A]: ##STR1## wherein, R.sub.1 represents a hydrogen atom or a substituent; R.sub.2 represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; Ar.sub.1 represents a hydrogen atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group; Ar.sub.2 represents a substituted or unsubstituted phenylene group or a substituted or unsubstituted naphthylene group; Ar.sub.3 and Ar.sub.4 independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted phenyl group or a substituted or unsubstituted naphthyl group; and n represents an integer of 0 or 1; and a compound containing in its chemical structure a hindered phenolic structure unit.
Abstract: A cyanide-free desensitizing or conversion solution for converting imaged electrophotographic masters to lithographic printing plates comprising:(a) from about 1.0 to about 3.0 percent of phytic acid;(b) from about 0.5 to about 2 percent of a water-soluble anionic polymer;(c) from about 1.0 to about 3.0 percent of a water-soluble dibasic acid; and(d) an aqueous carrier; all percentages being based upon the total weight of the solution, the pH of said solution ranging from about 3.5 to about 6.0.A method of using this solution to convert imaged masters is also disclosed.
Abstract: An electrophotographic photoreceptor comprising a support, a charge blocking layer, a first photoconductive layer composed of at least amorphous silicon, a second photoconductive layer composed of at least boron-containing amorphous silicon, a surface layer composed of at least nitrogenated amorphous silicon, the surface layer having an interface for contacting the second photoconductive layer, the surface layer including a lower region corresponding to an area not greater than approximately 100 .ANG. away from the interface, the lower region having a ratio of not less than 0.5 parts of nitrogen atoms for one part of silicon atoms, the nitrogen ratio of the lower region and the boron content of the second photoconductive layer corresponding to the relation B.gtoreq.10.sup.(9N-5.5) where B is the boron content in PPM and N is the ratio of nitrogen atoms to silicon atoms.
Abstract: An electrophotographic recording material comprising a conductive support and a photosensitive layer containing a photoconductive compound that has p-type charge transport capacity and corresponds to the following general formula (I): ##STR1## wherein: R.sup.1 represents a --NR.sup.3 R.sup.4 group, wherein each of R.sup.3 and R.sup.4 (same or different) represents a C.sub.1 -C.sub.10 alkyl group including said alkyl group in substituted form, a cycloalkyl group, or an aryl group, andR.sup.2 represents hydrogen, an alkyl group including a substituted alkyl group or halogen.
Type:
Grant
Filed:
June 16, 1989
Date of Patent:
May 8, 1990
Assignee:
Agfa-Gevaert, N.V.
Inventors:
Mark G. Van der Auweraer, Frans C. De Schrijver, Guy P. Verbeek, Carina Geelen, David R. Terrell, Stefaan K. De Meutter
Abstract: A toner for developing electrostatic images is disclosed which comprises a coloring agent, a styrene homopolymer or copolymer with a vinyl monomer or moners, and polypropylene having a number average molecular weight of about 3000 to 4000 in an amount between about 0.02 and 40 parts by weight per 100 parts by weight of the styrene homopolymer or copolymer.
Type:
Grant
Filed:
January 19, 1988
Date of Patent:
May 1, 1990
Assignee:
Konishiroku Photo Industry Co., Ltd.
Inventors:
Makoto Tomono, Noriyoshi Tarumi, Masayuki Sato