摘要:
The objects of the present invention are to provide a toner excellent in transferability, little remaining on the photosensitive member and causing no defective image in roll-aided transfer (or at least such a phenomenon is well-controlled), and also to provide an image forming method using the same toner. The above objects are achieved when the toner contains a binder resin and colorant, inorganic fine particles, and a hydrotalcite compound shown by the formula: M1y12+M2y22+ . . . Mjyj2+L1x13+L2x23+ . . . Lkxk3+(OH)2.(X/n)An−.mH2O (1) wherein 0
摘要:
A toner is principally constituted by a binder resin, a colorant and a wax. The toner has a maximum heat-absorption peak of 60-135° C. as measured by differential scanning calorimetry (DSC). The toner further has a viscoelastic characteristic measured at an angular frequency of the toner of 6.28 rad/sec including: a temperature giving a loss molecules G″ of 3×104 Pa of 90-115° C., a temperature giving a loss modulus G″ of 2×104 Pa of 95-120° C., a temperature giving a loss modulus G″ of 1×104 Pa of 105-135° C., a tan &dgr; (loss modulus G″/storage modulus G′) when G″=1×104-3×104 Pa of 0.6-2.0, a storage modulus at 170° C. (G′ (170° C.)) of 1×102-1×104 Pa, a loss modulus at 170° C. (G″ (170° C.)) of 1×102-1×104 Pa, and a ratio of a tan &dgr; at 170° C. (tan &dgr;170) to a tan &dgr; at 150° C. (tan &dgr;150) (tan &dgr;170/tan &dgr;150) of 1.05-1.6. The toner contains a tetrahydrofuran (THF)-soluble content exhibiting a molecular weight distribution according to gel permeation chromatography (GPC) chromatogram providing a main peak in a molecular weight region of 2,000-30,000 and a ratio (Mw/Mn) of above 100 between weight-average molecular weight (Mw) and number-average molecular weight (Mn). The resultant toner is effective in improving a low-temperature fixability and a high-temperature anti-offset characteristic while retaining an appropriate gloss of a fixed image in a broader temperature range.
摘要:
A magnetic black toner for electrophotography, includes: (a) magnetic black toner particles containing a binder resin, a magnetic material in 30-200 wt. parts per 100 wt. parts of the binder resin, and a first solid wax, and (b) first inorganic fine powder. The first solid wax (ii) provides a DSC heat-absorption main peak in a range of 60.degree.-120.degree. C., and (iii) shows a molecular weight distribution factor Mw/Mn of 1.0-2.0. The binder resin (iv) has a THF (tetrahydrofuran)-insoluble content of at most 5 wt. %, and (v) contains a THF-soluble content showing a GPC molecular weight distribution including a content (M1) of 40-70% in molecular weights of below 5.times.10.sup.4, a content (M2.ltoreq.M1) of 20-45% in molecular weights of 5.times.10.sup.4 -5.times.10.sup.5, and a content (M3
摘要:
A toner is constituted by at least a binder resin, a colorant and a wax. The binder resin has been formed from monomers including a vinyl monomer and polyester-forming monomers containing at least a polybasic carboxylic acid having three or more carboxyl groups or its anhydride, and comprises at least a hybrid resin comprising a vinyl polymer unit and a polyester unit.
摘要:
A toner for forming an image has toner particles containing at least a colorant, a binder resin and a wax. The toner has (i) a circularity distribution in which the toner has an average circularity of 0.900 to less than 0.965, contains 20 to 60% by number of particles with a circularity of less than 0.95 and has a mode circularity of 0.90 or more; and (ii) a particle size distribution in which the toner has a circle-equivalent average diameter of 2.0 to 10.0 .mu.m and has at least one peak of frequency by number in the region of a circle-equivalent diameter of 0.6 to 3.0 .mu.m and at least one peak of frequency by number in the region of a circle-equivalent diameter of from more than 3.0 .mu.m to 10.0 .mu.m. The wax has an endothermic main peak as measured by DSC of 60 to 120.degree. C. The binder resin contains THF soluble matter and 0 to 5.0% by weight of THF insoluble matter. The THF soluble matter having a molecular-weight distribution as measured by GPC in which the THF soluble matter has a content (M1) of 5% or less of a component with a molecular weight of less than 50,000, a content (M2) of 20 to 45% of a component with a molecular weight of 50,000 to 500,000, and a content (M3) of 2 to 25% of a component with a molecular weight exceeding 500,000 and the following condition (1) is satisfied:M1.gtoreq.M2>M3 (1)
摘要:
A developer capable of providing an excellent image without causing a charging failure even after a long-term and repeated use contains a toner particle having a binder resin and a colorant, an inorganic fine particle, and a conductive fine particle, in which a volume average particle diameter Da of the conductive fine particle and an number average primary particle diameter Db of the inorganic fine particle satisfy the expression (1) below, and a rate of liberation “a” of the conductive fine particle from the toner particle is 40 to 95% and a rate of liberation “b” of the inorganic fine particle from the toner particle is 0.1 to 5% Da≧10Db. (1)
摘要:
A toner exhibits excellent image characteristics, and also has an excellent charging property even if the toner is used in a cleaning-simultaneous-with-developing system having a direct injection charging mechanism. The toner includes toner particles and non-magnetic metallic-compound fine particles. The weight average particle diameter of the toner is 3.0 μm to 12.0 μm. The metallic-compound fine particles are conductive metallic-compound fine particles having a specific surface area (cm2/cm3) of 5×105 to 100×105; a medium diameter (D50) of 0.4 μm to 4.0 μm with respect to a volume-based particle diameter distribution, the medium diameter (D50) being smaller than the weight average particle diameter of the toner; and a 90% particle diameter D90 of 6.0 μm or less with respect to a volume-based particle diameter.
摘要:
A toner of the present invention comprises at least a binder resin comprising as a main component a polyester resin, a wax, and a colorant, in which in case of measuring a wettability of the toner with respect to a mixed solvent of methanol and water in terms of an optical transimittance at an optical wavelength of 780 nm, a methanol concentration of the mixed solvent is in a range of 45 to 65% by volume when an optical transmittance is 80% and 10%, respectively; a melt index (MI) is of 0.1 to 10 g/lO min at a temperature of 125° C. and a load of 5 kg; the toner comparises a resin component insoluble to tetrahydrofuran (THF insoluble component) in an amount of 5 to 40% by mass based on a mass of the binder resin; and the toner comprises a THF soluble component having a main peak in a molecular weight region of 3,000 to 20,000, and has a proportion of a component having a molecular weight of 10,000 or less in the THF soluble component is 50% by mass or more, according to a chromatogram of the THF soluble component measured by gel permeation chromatography. According to the toner of the present invention, it is possible to control lowering of an image density after leaving under a high temperature and high humidity environment, and a decline in the image density due to a charge-rise phenomenon upon low rate printing. Further, the toner has excellent fixing property and high temperature offset characteristic, and occurring of the end-offset is controlled.
摘要:
A toner of the present invention comprises at least a binder resin comprising as a main component a polyester resin, a wax, and a colorant, in which in case of measuring a wettability of the toner with respect to a mixed solvent of methanol and water in terms of an optical transimittance at an optical wavelength of 780 nm, a methanol concentration of the mixed solvent is in a range of 45 to 65% by volume when an optical transmittance is 80% and 10%, respectively; a melt index (MI) is of 0.1 to 10 g/10 min at a temperature of 125° C. and a load of 5 kg; the toner comparises a resin component insoluble to tetrahydrofuran (THF insoluble component) in an amount of 5 to 40% by mass based on a mass of the binder resin; and the toner comprises a THF soluble component having a main peak in a molecular weight region of 3,000 to 20,000, and has a proportion of a component having a molecular weight of 10,000 or less in the THF soluble component is 50% by mass or more, according to a chromatogram of the THF soluble component measured by gel permeation chromatography. According to the toner of the present invention, it is possible to control lowering of an image density after leaving under a high temperature and high humidity environment, and a decline in the image density due to a charge-rise phenomenon upon low rate printing. Further, the toner has excellent fixing property and high temperature offset characteristic, and occurring of the end-offset is controlled.
摘要:
A developer for developing an electrostatic image has a toner which contains a particulate toner, a particulate silica A and a particulate silica B. The toner has a weight-average particle size of not larger than 12.0 .mu.m and a particle-number distribution showing not more than 50% of toner particles not larger than 4.0 .mu.m in particle size and not more than 10% of toner particles not smaller than 10.08 .mu.m in particle size, each of the toner particles having a toner composition containing at least a polymer component and a charge controlling agent. The particulate silica A is composed of silicone oil-treated silica particles and has an average particle size of not larger than 0.1 .mu.m, while the particulate silica B is composed of silicone oil-treated silica particles and has an average particle size of 0.5 to 50 .mu.m. The particulate silica B also has a particle-number distribution showing not more than 50% of silica particles not larger than 1.0 .mu.m in particle size and not more than 10% of silica particles not smaller than 100 .mu.m in particle size. Also disclosed is an image forming method which uses this developer.