Abstract:
DNA sequences obtained from S. clavuligerus ATCC 27064, recombinant vectors incorporating such sequences and hosts transformed with such vectors are disclosed. The DNA comprises one or more genes coding for one or more enzymes involved in the biosynthesis of penicillin and cephalosporin &bgr;-lactams and such enzymes are expressed by hosts into which the recombinant vectors are transformed. The DNA and the enzymes encoded thereby have utility in the preparation of penicillins and cephalosporins, both known and novel, possessing pharmacological, especially antimicrobial, activity.
Abstract:
An electrophotographic toner for visualizing an electrostatic latent image formed by an electrophotographic process, an electrostatic printing process, an electrostatic recording process, etc., which is produced in consideration of the environment and safety. The electrophotographic toner includes a fixing resin and a colorant. The electrophotographic toner is a black toner using a titanium compound containing no carbon black as the colorant. The electrophotographic toner may be an electrophotographic two-component black toner using magnetic iron oxide containing no carbon black as the colorant.
Abstract:
A system and method for printing documents that are difficult to forge and that are easy to visually verify are disclosed. The system includes a colorant for printing an image on a surface of a document and a dye for forming a latent version of the image underneath the surface and a substrate that includes a migration agent for facilitating the migration of the dye through at least a portion of the substrate. The migration-enhancing agent may be coated onto a portion of the substrate or embedded within the substrate.
Abstract:
The present invention provides a toner for electrostatic image development which employs a black colorant free from a toxic substance and exhibits stable charge behavior even after extended use or printing of a large number of sheets, thus making it possible to provide printed images having sufficient image density without causing toner dispersion, fogging, and variation in image density. This is a toner for electrostatic image development comprising a binder resin and a colorant, wherein the colorant is made of black fine particles obtained by coating the surface of titanium dioxide particles with a complex oxide of titanium and iron.
Abstract:
A black toner for two-component development, comprising a resin binder; and a black colorant comprising a composite oxide of two or more metals, the composite oxide having a BET specific surface area of 7 m2/g or more; and a two-component developer comprising the black toner for two-component development and a resin-coated carrier. The black toner for two-component development can be suitably used for the development of a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.
Abstract:
An electrophotographic developer comprising at least one element selected from the group consisting of boron and phosphorus in a content of 0.1 to 100 ppm, which the developer is excellent in flowability and shelf stability, does not give image defects such as occurrence of white stripes and attains almost constant image quality even when the ambient conditions including temperature and humidity fluctuate. A production process of a polymerized toner used in the developer, a production process of the developer, and an image forming process.
Abstract:
Black magnetic toner comprising: a binder resin; and black magnetic composite particles having an average particle diameter of 0.06 to 1.0 nullm comprising: magnetic iron oxide particles, a coating layer formed on the surface of the magnetic iron oxide particles, comprising at least one organosilicon compound selected from the group consisting of: (1) organosilane compounds obtainable from alkoxysilane compounds, and (2) polysiloxanes or modified polysiloxanes, and a single carbon black coat formed on the coating layer comprising the organosilicon compound, in an amount of 26 to 55 parts by weight based on 100 parts by weight of the magnetic iron oxide particles.
Abstract:
A black toner comprising: a binder resin; and black non-magnetic composite particles having an average particle diameter of 0.06 to 1.0 nullm, comprising: hematite particles or iron oxide hydroxide particles as core particles; a single coating layer formed on the surface of said hematite particles or iron oxide hydroxide particles, comprising at least one organosilicon compound selected from the group consisting of: (1) organosilane compounds obtained from an alkoxysilane compounds, and (2) polysiloxanes or modified polysiloxanes; and a carbon black coat formed on said coating layer comprising said organosilicon compound, in an amount of 26 to 55 parts by weight based on 100 parts by weight of said hematite particles or iron oxide hydroxide particles.
Abstract:
An electrophotographic black toner comprising a colorant and a binder resin, wherein the toner has a metal oxide as the colorant of 20% by weight or less, said metal oxide having magnetization of 40 emu/g or smaller, and said toner has color coordinates such that L* has a value of 10 to 25, a* has a value of null3.0 to 3.0, and b* has a value of null3.0 to 3.0 as determined by a fixed image formed with the toner, as well as an electrophotographic developer and an image forming method using said electrophotographic black toner are provided. According to the present invention, the electrophotographic black toner having a high volume-specific resistance value, achieving a sufficient degree of blackness, less likely to cause high background and providing a high quality image can be obtained.
Abstract translation:一种包含着色剂和粘合剂树脂的电子照相黑调色剂,其中所述调色剂具有20重量%以下的着色剂的金属氧化物,所述金属氧化物的磁化强度为40emu / g以下,所述调色剂具有如下颜色坐标: L *的值为10〜25,a *为-3.0〜3.0,b *为通过由调色剂形成的固定图像确定的-3.0〜3.0的值,以及电子照相显影剂 并提供使用所述电子照相黑调色剂的图像形成方法。 根据本发明,可以获得具有高体积电阻率值,实现足够的黑度,不太可能导致高背景和提供高质量图像的电子照相黑调色剂。
Abstract:
A black toner composition comprises dried pigmented LC toner particles comprising a thermoplastic polymer and a carbon pigment having a BET value of up to about 140, and submicron particulate addendum material disposed on the dried pigmented LC toner particles. A process for forming the toner composition comprises: forming pigmented LC toner particles comprising a thermoplastic polymer and a carbon pigment having a BET value of up to about 140, drying the pigmented LC toner particles, and blending the dried pigmented LC toner particles with submicron particulate addendum material.