664 results about "Magnetic carriers" patented technology

A magnetic recording medium comprising: a nonmagnetic support having a first surface and a second surface; and a magnetic layer containing ferromagnetic powder and a binder, so that the magnetic layer, the first surface and the second surface are in this order, wherein the nonmagnetic support contains polyester, a difference between largest ratio and smallest ratio among peak intensity ratios of gauche / trans on the first and second surfaces of the support in a machine direction and a transverse direction obtained by ATR-FT-IR method is 0.030 or less in an absolute value, and a shrinkage factor of the magnetic recording medium after preservation at 70° C. 5% RH for one week is 0.040% or less.

A magnetic carrier having magnetic carrier particles each containing at least a magnetic core particle and a resin; the magnetic carrier having a resistivity of from 1.0×106 Ω·cm or more to 1.0×1010 Ω·cm or less at an electric-field intensity of 1.0×103 V / cm as found by measuring dynamic impedance; electric-field intensity E(109) at which the resistivity of the magnetic carrier comes to 1.0×109 Ω·cm being 2.0×104 V / cm or less, and electric-field intensity E(108) at which the resistivity of the magnetic carrier comes to 1.0×108 Ω·cm being from 5.0×103 V / cm or more to 2.8×104 V / cm or less; and the electric-field intensity E(108) and the electric-field intensity E(109) being in a ratio, E(108) / E(109), of from 1.0 or more to 5.0 or less.

The invention belongs to the technical field of bioseparation material, in particular to a magnetic composite microsphere with nucleocapsid structure and a preparation method thereof. Nano ferroferric oxide decorated by oleic acid is firstly used as raw material, and is polymerized through template fine emulsion so as to prepare the monodisperse magnetic composite microsphere with high magnet content; and then the monodisperse micosphere is polymerized through seed emulsion and is added with different amount of shell monomer to prepare the magnetic composite microsphere with the nucleocapsid structure and the magnet content of 20wt percent to 80wt percent. The grain size of nucleocapsid composite microsphere is in narrow distribution, and the magnet content of the microsphere is controllable and the surface has functional reactive group; therefore, the microsphere of the invention can be surface-modified into a magnetic carrier of biological active molecule by chemical crosslinking to be applied in the biomedicine field. The method of the invention can be simply operated and the process of which can be controlled, thus having industrialized prospect.

A magnetic coated carrier suitable for constituting a two-component type developer for use in electrophotography is composed of magnetic coated carrier particles comprising magnetic coated carrier particles comprising magnetic carrier core particles each comprising a binder resin and metal oxide particles, and a coating layer surface-coating each carrier core particle. The metal oxide particles have been subjected to a surface lipophilicity-imparting treatment. The magnetic carrier core particles have a resistivity of at least 1x1010 ohm.cm, and the magnetic coated carrier has a resistivity of at least 1x1012 ohm.cm. The magnetic coated carrier has a particle size distribution such that (i) it has a number-average particle size Dn of 5-100 mu m, (ii) it satisfies a relationship of Dn / sigma > / =3.5, wherein sigma denotes a standard deviation of number-basis particle size distribution of the carrier, and (iii) it contains at most 25% by number of particles having particle sizes of at most Dnx+E,fra 2 / 3+EE .

Provided is a two-component developer having excellent developing performance and little change in image concentration, and achieving long-term suppression of image defects such as transfer failure and fogging.Provided is a two-component developer containing a magnetic carrier and a toner, wherein the magnetic carrier has magnetic carrier particles comprising a silicone resin B coated on the surfaces of filled core particles in which pores of porous magnetic core particles are filled with a silicone resin A, the silicone resin A is a silicone resin cured in the presence of a non-metal catalyst or without a catalyst, while the silicone resin B is a silicone resin cured in the presence of a metal catalyst having titanium or zirconium, and the toner contains a binder resin, a release agent and a colorant, and has an average circularity of 0.940 or more.

The invention discloses a method for the assembly and the reflow soldering of a PCB and an FPC and a special positioning fixture thereof, which mainly solve the problems of inaccurate positioning, low efficiency of welding efficiency, difficulty for ensuring product quality and the like of manual assembly in the processes of assembling and soldering the PCB and the FPC. The method comprises the following steps: firstly, supporting, positioning and fixing the PCB by using a magnetic carrier board; secondly, carrying the FPC; next, preliminarily positioning the PCB and the FPC with a bonding agent; thirdly, printing a solder paster on a solder pad at the junction of the FPC and the PCB; and finally, pressing a magnetic cover board on the magnetic carrier board, fixing the positions of the FPC and the PCB, and performing the reflow soldering on the FPC and the PCB through a reflow oven. The method for the assembly and the reflow soldering of the PCB and the FPC and the special positioning fixture thereof have the advantages of simple operation, good reliability, great improvement on the production efficiency and the production quality of the FPC and the PCB in the processes of assembling and soldering, and processing cost reduction.

A magnetic carrier constituting a two-component developer for use in an electrophotographic image forming method is formed of a carrier core comprising a first resin and magnetic fine particles dispersed in the first resin, and a second resin surface-coating the carrier core. (a) The magnetic carrier has a true specific gravity of 2.5-4.5, a magnetization sigma 1000 as measured in a magnetic field of 1000x(103 / 4 pi )xA / m (1000 oersted) of 15-60 Am2 / kg (emu / g), a residual magnetization sigma r of 0.1-20 Am2 / kg (emu / g) and a resistivity of 5x1011-5x1015 ohm.cm. (b) The first resin has a polymer chain including a methylene unit (-CH2-). (c) The second resin has at least a fluoro-alkyl unit, a methylene unit (-CH2-) and an ester unit. (d) The carrier core is surface-coated with (i) a mixture of the second resin and a coupling agent having at least an amino group and a methylene unit, or (ii) a coupling agent having at least an amino group and a methylene unit, and then with the second resin.

A developing apparatus using a two-component developer constituted by a magnetic carrier and a toner, and an image forming apparatus comprising the developing apparatus. A developing unit and a stirring unit are provided, and in order to suppress toner scattering that may occur after a development operation has been halted for a long time, and thereby suppress contamination of the apparatus interior, the developer in a developing machine is transferred to a stirrer serving as a developer storage unit on the exterior of the developing machine when the development operation ends. Further, to extend the life of the developer, a range in which an angle of a restricting member upstream side central angle α, which is a central angle of the surface of a developing roller serving as a developer carrier on the upstream side of a restricting member opposing position opposing a doctor blade serving as a developer amount restricting member in a surface motion direction of the developing roller, is not less than 0[°] and not more than 60[°] is set as a low magnetic flux density area γ in which the maximum value of a normal direction magnetic flux density on the surface of the developing roller is not more than 30 [mT].

A two-component developer containing a magenta toner and a magnetic carrier, wherein the magenta toner has the characteristics: (i) when the concentration of the magenta toner in a solution of the magenta toner in chloroform is represented by Cm (mg / ml) and the absorbance of the solution at a wavelength of 538 nm is represented by A538, a relationship between Cm and A538 satisfies the relationship of 2.00<A538 / Cm<6.55; (ii) the lightness L* and chroma C* of the magenta toner determined in a powder state satisfy the relationships of 35≦L*≦45 and 60≦C*≦72; and (iii) the absolute value for the triboelectric charge quantity of the magenta toner measured by a two-component method using the magenta toner and the magnetic carrier is 50 mC / kg or more and 120 mC / kg or less.

An immune bead is made up of the magnetic carrier micro ball which combines at least one immune matching base. The micro ball is composed of the magnetic nm particle and the high molecular framework material which the core is the metal particle; the out of the core is high molecular framework, the out layer is the functional layer which can combines functional gene of different immune matching base. The manufacture method includes: the bead pretreatment, the bead activation, manufacture of the coupling antibody, closing the antibody with the confining liquid and purifying the immune bead. The detecting method is to detect the different things by the immunological response sandwich, the competition and the indirect method and set the control system on the testing board. The board is made up of the encrusting test paper, the coupling mat, the sample mat, the water suction mat, the coving film and the testing board outside calipers. It has the high sensitivity and accurate quantity; the regent is simple and cost low.

The present invention discloses a functionalized silicon coating mesoporous magnetic carrier. The carrier is a compound magnetic carrier having a core-shell structure formed by coating the magnetic ferroferric oxide with the silicon dioxide and an active amido or mercapto is bonded on the surface of the magnetic carrier and the active amido or mercapto can apply the selective chemisorption effect to the target chemical. The present invention simultaneously discloses a preparation method for the carrier, which in particular is that the thickness and uniformity of the silicon film are increased through two times of silicon coating processes so as to effectively protect the magnetic carrier from being corroded by acid and base in the application; the template agent on the surface of the carrier is detracted with high temperature under the inert atmosphere and the porecreating processing is applied to the surface of the carrier so as to increase the effective surface area of the carrier and enhance the processing performance. The fixed active bacterium for the funtionalized silicon coating mesoporous magnetic carrier can be applied in the treatment of the urban domestic sewage delivers good treatment effect and has important meaning to the environment protection.

The invention discloses a wastewater reuse method combining magnetic loading coagulation clarification and membrane separation. The method comprises the following steps: (1) a coagulant is added into a reaction tank to form small flocs; (2) the small flocs enter a loading and mixing tank to generate magnetic coagulation cores with magnetic carriers; (3) after the magnetic coagulation cores enter a flocculation tank, a flocculant is added to generate large-particle magnetic floccules; (4) after the magnetic floccules are stirred and dispersed strongly by a high-speed dispersion machine, magnetic carriers which are recycled via a magnetic drum separator return to the step (2), supernatant liquor enters a middle water tank via the collection by a water collecting pipe, after being pressurized by a water pump, the supernatant liquor enters membrane separating equipment for fine filtration, and filtered water is discharged for reusing. The method is used for removing particulate matters, colloid and a part of dissolved organic matters in advance before membrane filtration, so that membrane pollution degrees can be effectively avoided or reduced, and the cleaning period and the service life of membrane components are increased. The method can be used for the resource reutilization of the wastewater in industries of printing and dyeing, electroplating, paper-making and the like, as well as the upgrading and reconstruction and the tail water reuse of sewage treatment plants.

A method for manufacturing electrodes using an electrostatic deposition unit. In the first step of the process a mixture of magnetic carrier beads and a conductive powder is prepared in the sump of the deposition unit; the mixture forms a magnetic brush on the sleeve of the deposition unit. In the second step of the process, the substrate is positioned away from the magnetic brush to form an air gap. In the third step of the process, a voltage is applied between the substrate and the sleeve of the deposition unit in order to produce a large asymmetry between the magnetic brush and said substrate such that the electric field at the magnetic brush is at least 3.0 times as great as the electric field at the substrate. In the fourth step of the process, conductive powder is deposited onto the substrate.