摘要:
A toner for developing an electrostatic image is provided as a pulverized mixture including a binder resin and a colorant. The binder resin is characterized by a molecular weight distribution on a GPC chromatogram of its tetrahydrofuran (THF)-soluble resin content including at least 15% and below 35% of a resin component in a molecular weight region of at most 5000 and at least 3 wt. % of a resin component in a molecular weight region of at least 5.times.10.sup.6 and showing a main peak in a molecular weight region of 5000 to 10.sup.5. The binder resin also has an acid value of 2-100 mg KOH/g. The THF-soluble resin component in the molecular weight region of at least 5.times.10.sup.6 is enriched during a melt-kneading step during the toner production.
摘要:
A developer for developing an electrostatic image has a toner, fine resin particles with a surface shape sphericity .psi. of from 0.90 to 0.50, and fine inorganic particles.
摘要:
A developer for developing an electrostatic image has a toner, fine resin particles with a surface shape sphericity .psi. of from 0.90 to 0.50, and fine inorganic particles.
摘要:
An electrostatic image supporting member which supports an electrostatic image and a toner carrying member for conveying a magnetic toner are disposed in a development section with a specified gap therebetween. The toner carrying member has a base whose surface has an average surface roughness (Ra) of 1.0 to 3.0 .mu.m. A resin coating containing electrically conductive fine particles is formed on the base surface at a density of 4 to 12 g per 1 m.sup.2. The outer layer of the coating has an Ra from 0.8 to 3.0 .mu.m. The toner carrying member carries an electrically insulating magnetic toner containing at least a binder resin and a magnetic component, and satisfying the conditions of a volumetric average particle size of 4.5 to 8 .mu.m, a BET specific surface area of 1.8 to 3.5 m.sup.2 /g, a charge amount of -20 to -35 .mu.c/g, a loose-state apparent density of 0.40 to 0.52 g/cm.sup.3, and a true specific gravity of 1.45 to 1.8. The magnetic toner is formed into a layer having a thickness smaller than the dimension of the gap by a member for regulating the thickness by pressing the toner against the toner carrying member. The magnetic toner is then conveyed to the development section, in which the toner develops the electrostatic image while an AC electric field is applied.
摘要翻译:支撑静电图像的静电图像支撑构件和用于输送磁性调色剂的调色剂承载构件以其间具有特定间隙的方式设置在显影区域中。 调色剂承载构件具有表面的平均表面粗糙度(Ra)为1.0〜3.0μm的基材。 含有导电性微粒的树脂被膜以4〜12g / 1m 2的密度形成在基材表面上。 涂层的外层的Ra为0.8〜3.0μm。 调色剂承载构件承载至少含有粘合剂树脂和磁性组分的电绝缘磁性调色剂,并且满足体积平均粒径为4.5至8μm的条件,BET比表面积为1.8至3.5m 2 / g ,电荷量为-20〜-35μC/ g,松散状态表观密度为0.40〜0.52g / cm 3,真比重为1.45〜1.8。 磁性调色剂通过将调色剂压靠在调色剂承载部件上而调节厚度的部件形成为厚度小于间隙尺寸的层。 然后将磁性调色剂输送到显影部分,其中调色剂在施加AC电场时显影静电图像。
摘要:
An image forming apparatus includes a member to be charged for carrying an electrostatic image, a contact-charging means for charging the member to be charged in contact with the member to be charged, and a developing means for developing the electrostatic image carried on the member to be charged. The developing means includes a developer for developing the electrostatic image comprising a toner and hydrophobic inorganic fine powder. The hydrophobic inorganic fine powder not only improves the fluidity of the developer and adjusts the chargeability of the developer but also prevents difficulties due to interaction between the member to be charged and the contact charging means in the presence of residual developer, such as damages of the member to be charged and toner-sticking onto the member to be charged.
摘要:
A developer for developing electrostatic latent images is constituted by a toner, and negatively chargeable spherical resin particles having an average particle size of 0.03-1.0 micron and a volume resistivity of 10.sup.6 -10.sup.12 ohm.cm. The toner may comprise toner particles and hydrophobic inorganic fine powder, which is generally used in a larger amount than the negatively chargeable spherical resin particles. The negatively chargeable spherical resin particles function to provide a toner image which is faithful to an electrostatic latent image formed on a photosensitive member while preventing toner-sticking onto the photosensitive member preferably in combination with a contact-charging means for charging the photosensitive member.
摘要:
A developer for developing electrostatic latent images is constituted by a toner, and negatively chargeable spherical resin particles having an average particle size of 0.03-1.0 micron and a volume resistivity of 10.sup.6 -10.sup.12 ohm.cm. The toner may comprise toner particles and hydrophobic inorganic fine powder, which is generally used in a larger amount than the negatively charageable spherical resin particles. The negatively chargeable spherical resin particles function to provide a toner image which is faithful to an electrostatic latent image formed on a photosensitive member while preventing toner-sticking onto the photosensitive member preferably in combination with a contact-charging means for charging the photosensitive member.
摘要:
A toner for developing an electrostatic image, comprises a binder resin and a colorant. The toner has a glass transition temperature (Tg) of 65.degree. C. or lower. The binder resin comprises a styrene-acrylic copolymer formed from at least a styrenic monomer and a mixture of two or more acrylic monomers. The binder resin contains 10% by weight or more of THF insolubles. The amount of the styrenic monomer remaining in the toner is 0.005 part or less by weight based on 100 parts by weight of the binder resin component in the toner (50 ppm), and the amount of the acrylic monomers remaining in said toner is 0.001 part by weight based on 100 parts by weight or less of the binder resin component in the toner (10 ppm). At least one component of the mixture of acrylic monomers has a Q-value of 0.5 to less than 1.0 and the other has a Q-value of 0.3 to less than 0.5.This toner is excellent in the anti-off-set property to a fixing roller surface, good in fixability, giving high image density and little odor.
摘要:
A magnetic developer for developing an electrostatic latent image, including hydrophobic silica fine powder and an insulating magnetic toner comprising at least a binder resin and a magnetic material comprising spherical magnetic particles; wherein 0.16 to 1.6 wt. parts of the hydrophobic silica fine powder is mixed with 100 wt. parts of the insulating magnetic toner; the developer contains 17-60% by number of magnetic toner particles having a particle size of 5 microns or smaller, 5-50% by number of magnetic toner particles having a particle size of 6.35-10.08 microns, and 2.0% by volume or less of magnetic toner particles having a particle size of 12.7 microns or larger.
摘要:
An image forming apparatus includes a member to be charged for carrying an electrostatic latent image; a contact charging means for contact charging the member to be charged and a developing means for developing the latent image. The developing means includes a developer having a magnetic toner and fine powder treated with a silicone oil or varnish-treating agent, wherein the magnetic toner particles include a binder resin and contain from 10-70 wt. % of magnetic fine powder. An image forming method includes the steps of contact charging, latent image forming and developing with a developer having the binder resin, 10 to 70 wt. % magnetic fine powder and fine powder treated with a silicone oil or varnish-treating agent.