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Patent US6002903 - Detachable support - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsAn apparatus unit includes a detachably mounted unit having a developing sleeve, a toner and a toner applicator, all of which are enclosed by an outer casing. The toner has a shape factor SF-1 of 100-150 and is formed of 100 parts binder, 1-20 parts of a non-magnetic color and 5-40 parts wax and has...http://www.google.com/patents/US6002903?utm_source=gb-gplus-sharePatent US6002903 - Detachable supportAdvanced Patent SearchPublication numberUS6002903 APublication typeGrantApplication numberUS 09/006,900Publication dateDec 14, 1999Filing dateJan 14, 1998Priority dateMay 15, 1995Fee statusPaidPublication number006900, 09006900, US 6002903 A, US 6002903A, US-A-6002903, US6002903 A, US6002903AInventorsKengo Hayase, Tatsuya Nakamura, Tatsuhiko ChibaOriginal AssigneeCanon Kabushiki KaishaExport CitationBiBTeX, EndNote, RefManPatent Citations (23), Referenced by (31), Classifications (15), Legal Events (5) External Links: USPTO, USPTO Assignment, EspacenetDetachable supportUS 6002903 AAbstract An apparatus unit includes a detachably mounted unit having a developing sleeve, a toner and a toner applicator, all of which are enclosed by an outer casing. The toner has a shape factor SF-1 of 100-150 and is formed of 100 parts binder, 1-20 parts of a non-magnetic color and 5-40 parts wax and has a specific storage modulus ratio (a) at 60� C. and 80� C. and (b) at 155� C. and 190� C., of at least 80 for (a) and of 0.95-5 for (b). Toner images are visualized by forming an electrostatic image, developing the electrostatic image with the toner, transferring the toner image to a transfer material and fixing the toner image by heat and pressure.
What is claimed is: 1. An apparatus unit, detachably mountable to an apparatus main assembly, comprising:a toner, a developing sleeve, a toner application means disposed to press the developing sleeve, and an outer casing for enclosing the toner, the developing sleeve and the toner application means; wherein the toner comprises 100 wt. parts of a binder resin, 1-20 wt. parts of a non-maqnetic colorant and 5-40 wt. parts of a low-softening point substance; the toner is a non-magnetic toner selected from the group consisting of a non-magnetic cyan toner, a non-magnetic yellow toner, a non-magnetic magenta toner and a non-magnetic black toner; the toner has a shape factor SF-1 of 100-150; and the toner has a storage modulus at 60� C. (G'60) and a storage modulus at 80� C. (G'80) providing a ratio (G'60 /G'80) of at least 80 and a storage modulus at 155� C. (G'155) and a storage modulus at 190� C. (G'190) providing a ratio (G'155 /G'190) of 0.95-5. 2. The apparatus unit according to claim 1, wherein the developing sleeve comprises a cylinder formed of an electroconductive metal or alloy, and the toner application means comprises a toner application roller and an elastic blade.
3. The apparatus unit according to claim 1, wherein the developing sleeve comprises a cylinder formed of an electroconductive metal or alloy, and the toner application means comprises a plurality of toner application rollers.
4. The apparatus unit according to claim 1, wherein the developing sleeve is coated with a surface layer comprises a resin and electroconductive fine powder dispersed therein.
5. The apparatus unit according to claim 1, wherein the toner shows a ratio (G'60 /G'80) of 100-400.
6. The apparatus unit according to claim 1, wherein the toner shows a ratio (G'60 /G'80) of 150-300.
7. The apparatus unit according to claim 1, wherein the toner shows a ratio (G'155 /G109) of 1-5.
8. The apparatus unit according to claim 1, wherein the toner has a storage modulus at 190� C. (G'190) of 1�103 -1�104 dyn/cm2.
9. The apparatus unit according to claim 1, wherein the toner provides a loss modulus curve giving a maximum (G"max) of at least 1�109 dyn/cm2 in a temperature range of 40-65� C.
10. The apparatus unit according to claim 9, wherein the toner shows a loss modulus at 40� C. of G"40 giving a ratio (G"max /G"40) of at least 1.5.
11. The apparatus unit according to claim 1, wherein the binder resin has a THF-insoluble content of 0.1-20 wt. %.
12. The apparatus unit according to claim 11, wherein the binder resin has a THF-insoluble content of 1-15 wt. %.
13. The apparatus unit according to claim 1, wherein the binder resin comprises a crosslinked styrene copolymer, and the low-softening point substance provides a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 40-90� C.
14. The apparatus unit according to claim 1, wherein the binder resin comprises a crosslinked styrene copolymer and a non-crosslinked polyester resin, and the low-softening point substance provides a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 40-90� C.
15. The apparatus unit according to claim 1, wherein the binder resin comprises a crosslinked styrene copolymer and a crosslinked polyester resin, and the low-softening point substance provides a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 40-90� C.
16. The apparatus unit according to claim 1, wherein the low-softening point substance provides a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 45-85� C., the heat-absorption main peak having a half-value width of at most 10� C.
17. The apparatus unit according to claim 16, wherein the low-softening point substance shows a heat-absorption main peak having a half-value width of at most 5� C.
18. The apparatus unit according to claim 1, wherein the low-softening point substance comprises a solid wax.
19. The apparatus unit according to claim 1, wherein the low-softening point substance comprises a solid ester wax.
20. The apparatus unit according to claim 1, wherein the low-softening point substance comprises a solid ester wax providing a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 45-85� C., the heat-absorption main peak having a half-value width of at most 10� C.
21. The apparatus unit according to claim 20, wherein the solid ester wax shows a heat-absorption main peak having a half-value width of at most 5� C.
22. The apparatus unit according to claim 1, wherein the low-softening point substance comprises a solid polymethylene wax providing a DSC heat-absorption peak showing a heat-absorption main in a temperature range of 40-90� C., the heat-absorption peak having a half-value width of at most 10� C.
23. The apparatus unit according to claim 1, wherein the low-softening point substance comprises a solid polyolefin wax providing a DSC heat-absorption peak showing a heat-absorption main in a temperature range of 40-90� C., the heat-absorption peak having a half-value width of at most 10� C.
24. The apparatus unit according to claim 1, wherein the low-softening point substance comprises a long-chain alkyl alcohol having 15-100 carbon atoms and providing a DSC heat-absorption peak showing a heat-absorption main in a temperature range of 40-90� C., the heat-absorption peak having a half-value width of at most 10� C.
25. The apparatus unit according to claim 1, wherein the toner is in the form of toner particles containing 11-30 wt. % thereof of the low-softening point substance.
26. The apparatus unit according to claim 25, wherein the low-softening point substance is contained in 12-35 wt. part per 100 wt. parts of the binder resin.
27. The apparatus unit according to claim 1, wherein the toner is a non-magnetic cyan toner.
28. The apparatus unit according to claim 1, wherein the toner is a non-magnetic magenta toner.
29. The apparatus unit according to claim 1, wherein the toner is a non-magnetic yellow toner.
30. The apparatus unit according to claim 1, wherein the toner is a non-magnetic black toner.
31. The apparatus unit according to claim 1, wherein the toner has a shape factor SF-1 of 100-125.
32. The apparatus unit according to claim 1, wherein the toner has an agglomeratability of 1-30%.
33. The apparatus unit according to claim 1, wherein the toner has an agglomeratability of 4-20%.
34. An image forming method, comprising:forming an electrostatic image on an image-bearing member; developing the electrostatic image with a toner having a triboelectric charge to form a toner image; transferring the toner image onto a transfer material via or without via an intermediate transfer member; and fixing the toner image onto the transfer member under application of heat and pressure; wherein the toner comprises 100 wt. parts of a binder resin, 1-20 wt. parts of a non-magnetic colorant and 5-40 wt parts of a low-softening point substance; the toner is a non-magnetic toner selected from the group consisting of a non-magnetic cyan toner, a non-magnetic yellow toner, a non-magnetic magenta toner and a non-magnetic black toner; the toner has a shape factor SF-1 of 100-150; and the toner has a storage modulus at 60� C. the toner has a storage modulus at 60� C. (G'60) and a storage modulus at 80� C. (G'80) providing a ratio (G'60 /G'80) of at lease 80 and a storage modulus at 155� C. (G'155) and a storage modulus at 190� C. (G'190) providing a ratio (G'155 /G'190) of 0.95-5 35. The method according to claim 34, whereinthe electrostatic image is formed on a photosensitive member, the electrostatic image is developed with a toner triboelectrically charged by a toner application roller to form a toner image on the photosensitive member, the toner image on the photosensitive member is transferred onto an intermediate transfer member, the toner image on the intermediate transfer member is transferred onto the transfer material, and the toner image is fixed onto the transfer material under application of heat and pressure. 36. The method according to claim 35, wherein the photosensitive member is charged by a contact charging means and then exposed to form the electrostatic image thereon.
37. The method according to claim 35, wherein the intermediate transfer member is in the form of a drum supplied with a voltage, and the surface thereof is cleaned by a cleaning means.
38. The method according to claim 35, wherein the intermediate transfer member is in the form of a drum supplied with a voltage, and the toner image on the intermediate transfer member is transferred to the transfer material under the action of a transfer belt supplied with a voltage, carrying the transfer material and exerting a pressing force against the intermediate transfer member via the transfer material.
39. The method according to claim 35, wherein the intermediate transfer member is in the form of an endless belt supplied with a voltage, and the toner image on the intermediate transfer is transferred to the transfer material under the action of a transfer roller supplied with a voltage and carrying the transfer material so as to sandwich the transfer material together with the intermediate transfer member.
40. The method according to claim 35, comprising multi-color or full-color image forming steps including:(a) forming a first electrostatic image on the photosensitive member, developing the first electrostatic image formed on the photosensitive member with a first toner selected from the consisting of a yellow toner, a cyan toner, a magenta toner and a black toner to form a first toner image on the photosensitive member, and transferring the first toner image from the photosensitive member onto the intermediate transfer member, (b) forming a second electrostatic image on the photosensitive member, developing the second electrostatic image with a second toner having a different color from the first toner to form a second toner image on the photosensitive member and transferring the second toner image from the photosensitive member to the intermediate transfer member, (c) forming a third electrostatic image on the photosensitive member, developing the third electrostatic image with a third toner having a different color from the first and second toners to form a third toner image on the photosensitive member and transferring the third toner image from the photosensitive member to the intermediate transfer member, (d) forming a fourth electrostatic image on the photosensitive member, developing the fourth electrostatic image with a fourth toner having a different color from the first to third toners to form a fourth toner image on the photosensitive member and transferring the fourth toner image from the photosensitive member to the intermediate transfer member, (e) transferring the first to fourth toner images on the intermediate transfer member onto the transfer material, and (f) fixing the first to fourth toner images on the transfer material under application of heat and pressure to form a multi-color or full-color image on the transfer material. 41. The method according to claim 40, wherein each of the yellow toner, the cyan toner and the magenta toner satisfies the properties recited in claim 34.
42. The method according to any of claims 34 to 40, wherein the toner image on the transfer material is fixed under application of heat and pressure by using a heating roller to which an offset-prevention liquid is not applied.
43. The method according to claim 42, wherein the heating roller is surfaced with a fluorine-containing resin.
44. The method according to claim 34, wherein the toner shows a ratio (G'60 /G'80) of 100-400.
45. The method according to claim 34, wherein the toner shows a ratio (G'60 /G'80) of 150-300.
46. The method according to claim 34, wherein the toner shows a ratio (G'155 /G'190) of 1-5.
47. The method according to claim 34, wherein the toner has a storage modulus at 190� C. (G'190) of 1�103 -1�104 dyn/cm2.
48. The method according to claim 34, wherein the toner provides a loss modulus curve giving a maximum (G"max) of at least 1�109 dyn/cm2 in a temperature range of 40-65� C.
49. The method according to claim 48, wherein the toner shows a loss modulus at 40� C. of G"40 giving a ratio (G"max /G"40) of at least 1.5.
50. The method according to claim 34, wherein the binder resin has a THF-insoluble content of 0.1-20 wt. %.
51. The method according to claim 50, wherein the binder resin has a THF-insoluble content of 1-15 wt. %.
52. The method according to claim 34, wherein the binder resin comprises a crosslinked styrene copolymer, and the low-softening point substance provides a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 40-90� C.
53. The method according to claim 34, wherein the binder resin comprises a crosslinked styrene copolymer and a non-crosslinked polyester resin, and the low-softening point substance provides a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 40-90� C.
54. The method according to claim 34, wherein the binder resin comprises a crosslinked styrene copolymer and a crosslinked polyester resin, and the low-softening point substance provides a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 40-90� C.
55. The method according to claim 34, wherein the low-softening point substance provides a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 45-85� C., the heat-absorption main peak having a half-value width of at most 10� C.
56. The method according to claim 55, wherein the low-softening point substance shows a heat-absorption main peak having a half-value width of at most 5� C.
57. The method according to claim 34, wherein the low-softening point substance comprises a solid wax.
58. The method according to claim 34, wherein the low-softening point substance comprises a solid ester wax.
59. The method according to claim 34, wherein the low-softening point substance comprises a solid ester wax providing a DSC heat-absorption curve showing a heat-absorption main peak in a temperature range of 45-85� C., the heat-absorption main peak having a half-value width of at most 10� C.
60. The method according to claim 59, wherein the solid ester wax shows a heat-absorption main peak having a half-value width of at most 5� C.
61. The method according to claim 34, wherein the low-softening point substance comprises a solid polymethylene wax providing a DSC heat-absorption peak showing a heat-absorption main in a temperature range of 40-90� C., the heat-absorption peak having a half-value width of at most 10� C.
62. The method according to claim 34, wherein the low-softening point substance comprises a solid polyolefin wax providing a DSC heat-absorption peak showing a heat-absorption main in a temperature range of 40-90� C., the heat-absorption peak having a half-value width of at most 10� C.
63. The method according to claim 34, wherein the low-softening point substance comprises a long-chain alkyl alcohol having 15-100 carbon atoms and providing a DSC heat-absorption peak showing a heat-absorption main in a temperature range of 40-90� C., the heat-absorption peak having a half-value width of at most 10� C.
64. The method according to claim 34, wherein the toner is in the form of toner particles containing 11-30 wt. % thereof of the low-softening point substance.
65. The method according to claim 64, wherein the low-softening point substance is contained in 12-35 wt. part per 100 wt. parts of the binder resin.
66. The method according to claim 34, wherein the toner is a non-magnetic cyan toner.
67. The method according to claim 34, wherein the toner is a non-magnetic magenta toner.
68. The method according to claim 34, wherein the toner is a non-magnetic yellow toner.
69. The method according to claim 34, wherein the toner is a non-magnetic black toner.
70. The method according to claim 34, wherein the toner has a shape factor SF-1 of 100-125.
71. The method according to claim 34, wherein the toner has an agglomeratability of 1-30%.
72. The method according to claim 34, wherein the toner has an agglomeratability of 4-20%.
This application is a division of U.S. Ser. No. 08/647,727, filed on May 15, 1996, now U.S. Pat. No. 5,753,399.
FIELD OF THE INVENTION AND RELATED ART The present invention relates to a toner for developing electrostatic images used in image forming methods, such as electrophotography or electrostatic recording, particularly a toner suitable for heat and pressure fixation, and also an apparatus unit including the toner and an image forming method using the toner.
Hitherto, a large number of electrophoto-graphic processes have been known, inclusive of those disclosed in U.S. Pat. Nos. 2,297,691; 3,666,363; and 4,071,361. In these processes, in general, an electrostatic latent image is formed on a photosensitive member comprising a photoconductive material by various means, then the latent image is developed with a toner, and the resultant toner image is, after being directly or indirectly transferred onto a transfer(-receiving) material such as paper etc., as desired, fixed by heating, pressing, or heating and pressing, or with solvent vapor to obtain a copy or print carrying a fixed toner image. A portion of the toner remaining on the photosensitive member without being transferred is cleaned by various means, and the above mentioned steps are repeated for a subsequent cycle of image formation.
Japanese Laid-Open Patent Application (JP-A) 1-128071 has disclosed a toner for developing electrostatic images comprising a polyester resin as a binder resin and a specific storage modulus at 95� C. However, it has been further desired to provide a toner showing a smaller lowering in storage modulus in a temperature range of 60-80� C., providing fixed images of a more uniform gloss and showing a better low-temperature fixability.
JP-A 4-353866 has disclosed a toner for electrophotography having rheological properties including a storage modulus lowering initiation temperature in the range of 100-110� C., a specific storage modulus at 150� C. and a loss modulus peak temperature of at least 125� C. However, the storage modulus lowering initiation temperature is too high and the loss modulus peak temperature is too high, so that it is necessary to improve the low-temperature fixability.
JP-A 6-59504 has disclosed a toner composition comprising a polyester resin of a specific structure as a binder resin. The toner composition is also characterized by a specific storage modulus at 70-120� C. and a specific loss modulus at 130-180� C. Because the toner does not contain a low-softening point substance as an essential component, the toner has an inferior low-temperature fixability and is liable to cause a remarkable change in storage modulus in a temperature region of 155� C. or higher, thus being liable to result in a gloss change.
Further, a copying machine or a printer for full-color image formation is becoming to be used. A full-color image is generally formed through a process as follows. A photosensitive member is uniformly charged by a primary charger and is exposed imagewise with laser light modulated by a magenta image signal based on an original to form an electrostatic image on the photosensitive member, which is developed by using a magenta developing device containing a magenta toner to forma magenta toner image. The magenta toner image on the photosensitive member is then transferred to a transferred material conveyed thereto directly or indirectly via an intermediate transfer member.
Further, in a full-color image forming apparatus using non-magnetic color toners, a two-component type developer comprising a non-magnetic color toner and a magnetic carrier is generally used to develope electrostatic images according to the magnetic brush developing scheme. In the magnetic brush developing method using a two-component type developer, it is necessary to adjust a constant mixing ratio between the toner and the carrier, so that the developing device equipped with such means is liable to be large in size. Accordingly, in order to provide a small-size full-color image forming apparatus, it is desirable to use a developing device (apparatus unit) capable of developing electrostatic images according to the non-magnetic mono-component developing scheme, e.g., as shown in FIG. 6, which however requires a non-magnetic color toner that can exhibit a continuous image forming characteristic for a large number of sheets while enduring a pressure and abrasion by a toner application roller 18 and an elastic blade 19, is less liable to cause offset even when fixed by using a heating roller not supplied with an offset-preventing liquid and exhibits good color mixing characteristic.
SUMMARY OF THE INVENTION A generic object of the present invention is to provide a toner for developing electrostatic images having solved the above-mentioned problems.
According to the present invention, there is provided a toner for developing an electrostatic image, comprising: 100 wt. parts of a binder resin, 1-150 wt. parts of a colorant and 5-40 wt. parts of a low-softening point substance; wherein the toner has a storage modulus at 60� C. (G'60) and a
storage modulus at 80� C. (G'80) providing a ratio (G'60 /G'80) of at least 80, and
a storage modulus at 155� C. (G'155) and a storage modulus at 190� C. (G'190) providing a ratio (G'155 /G'190) of 0.95-5.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing a storage modulus curve, a loss modulus curve and a tan (δ) curve of a toner according to the invention.
DETAILED DESCRIPTION OF THE INVENTION The toner for developing electrostatic images according to the present invention accomplishes a low-temperature fixability and a suppression of gloss (value) change at different fixing temperatures by satisfying characteristic viscoelasticities including a storage modulus at 60� C. (G'60) and a storage modulus at 80� C. (G'80) providing a ratio (G'60 /G'80) of at least 80, and a storage modulus at 155� C. (G'155) and a storage modulus at 190� C. (G'190) of 0.95-5.0.
In the toner of the present invention, G'60, G'80 and ratio (G'60 /G'80) represent combined storage modulus characteristics of the binder resin and low-softening point substance in a state of transition from a glass state or glass transition state where deformation is not readily caused by an external stress to a deformable state. A ratio (G'60 /G'80) of at least 80 means that the toner causes an abrupt lowering in elasticity in the course of heating from 60� C. to 80� C., and allows good low-temperature fixation in the heating and pressing fixation step, so that the toner image can be well fixed onto a transfer material from immediately after a start of power supply to an apparatus main body in a cold environment. The ratio (G'60 /G'80) may preferably be 100 to 400, more preferably 150 to 300.
The toner according to the present invention may preferably show a G'60 of 1�108 -1�1010 dyn/cm2, more preferably 2�108 -9�109 dyn/cm2, further preferably 3�108 -5�109 dyn/cm2, so as to exhibit good continuous image forming characteristic on a large number of sheets while enduring pressure and abrasion in the developing device.
It is further preferred that the toner according to the present invention provides a loss modulus curve showing a maximum (G"max) of at least 1�109 dyn/cm2, more preferably 1�109 -1�1010 dyn/cm2, in a temperature range of 40-65� C., so as to exhibit improved anti-blocking performance and continuous image forming characteristic. It is further preferred to show a loss modulus at 40� C. (G"40) giving a ratio (G"max /G"40) of at least 1.5.
There is generally found a correlation between the storage modulus of a toner at a fixing temperature and a gloss value of the fixed image. For example, a higher toner storage modulus provides a lower gloss value of a fixed toner image, and a lower temperature-dependent change in storage modulus results in a smaller change in gloss value. Accordingly, the ratio (G'155 /G'190) provides an effective measure for evaluating the degree of gloss value change of fixed toner images corresponding to a change in fixing temperature around 180� C.
The G'155 /G'190 of the toner according to the present invention is set to be in the range of 0.95-5, more preferably 1-5, so as to provide a smaller gloss value change in response to a fixing temperature change. Further, in order to provide a color-mixing characteristic while retaining the anti-offset characteristic, the toner may preferably have G'190 of 1�103 -1�104 dyn/cm2.
The binder resin for the toner of the present invention may for example comprise: polystyrene; homopolymers of styrene derivatives, such as poly-p-chlorostyrene and polyvinyltoluene; styrene copolymers such as styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, styrene-methyl-α-chloromethacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer and styrene-acrylonitrileindene copolymer; acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyamide resin, furan resin, epoxy resin and xylene resin. These resins may be used singly or in combination of two or more species.
In the case of using a binder resin comprising principally a crosslinked styrene copolymer, the binder resin may preferably contain a THF-soluble component providing a molecular weight distribution according to gel permeation chromatograph (GPC) showing a main peak in a molecular weight region of 3�103 -5�104 and a sub-peak or shoulder in a molecular weight region of at least 105. It is further preferred to have totally 2 or more sub-peak(s) and/or shoulder(s) in the molecular weight region of at least 105. The binder resin comprising principally a styrene copolymer may preferably contain a THF-insoluble content of 0.1-20 wt. %, preferably 1-15 wt. %.
0.5-1.0 g of a toner sample is weighed (at W1 g) and placed in a cylindrical filter paper (e.g., "No. 86R", available from Toyo Roshi K. K.), which is mounted on a Soxhlet's extractor. Then, the sample is subjected to 6 hours of extraction with 100-200 ml of solvent THF, and the soluble content extracted with THF is subjected to evaporation of THF and dried under vacuum for several hours at 100� C. to be weighed (at W2 g). Based on the measured values and the weight (W3 g) of the components, such as the pigment and the wax, other than the resin component, the THF insoluble content is calculated by the following equation:
THF insoluble content (wt. %)={[W1 -(W3 +W2)]/(W1 -W3)}�100
In the case of a binder resin comprising a polyester resin, the binder resin may preferably have such a molecular weight distribution that it shows at least one peak in a molecular weight region of 3�103 -5�104 and contains 60-100 wt. % of a component having a molecular weight of at most 105. It is further preferred that at least one peak is present in a molecular weight region of 5�103 -2�104.
The low-softening point substance used in the present invention may preferably have a heat-absorption main peak in a temperature region of 40-90� C., more preferably 45-85� C., on its DSC heat-absorption curve. The low-softening point substance may preferably be one showing a sharp-melting characteristic peak as represented by the heat-absorption main peak having a half-value width of at most 10� C., more preferably at most 5� C. The low-softening point substance may particularly preferably comprise an ester wax comprising principally an ester compound between a long-chain alkyl alcohol having 15-45 carbon atoms and a long-chain alkyl carboxylic acid having 15-45 carbon atoms.
The charge control agent used in the present invention may be those of negative-type or positive-type. Specific examples of the negative charge control agent may include: metal-containing acid-based compounds comprising acids such as salicylic acid, alkylsalicylic acid, dialkylsalicylic acid, naphthoic acid, dicarboxylic acid and derivatives of these acids; polymeric compounds having a side chain comprising sulfonic acid or carboxylic acid; boron compound; urea compounds; silicon compound; and calixarene. Specific examples of the positive charge control agent may include: quaternary ammonium salts; polymeric compounds having a side chain comprising quaternary ammonium salts; guanidine compounds; and imidazole compounds.
The polymerizable monomer suitably used for producing toner particles according to the polymerization process may suitably be a vinyl-type polymerizable monomer capable of radical polymerization. The vinyl-type polymerizable monomer may be a monofunctional monomer or a polyfunctional monomer. Examples of the monofunctional monomer may include: styrene; styrene derivatives, such as α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, and p-phenylstyrene; acrylic monomers, such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethylphosphateethyl acrylate, diethylphosphateethyl acrylate, dibutylphosphateethyl acrylate, and 2-benzoyloxyethyl acrylate; methacrylic monomers, such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butylmethacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, diethylphosphate-ethyl methacrylate, and dibutylphosphateethyl methacrylate; methylene aliphatic monocarboxylic acid esters; vinyl esters, such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl lactate, and vinyl formate; vinyl ethers, such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether; and vinyl ketones, such as vinyl methyl ketone, vinyl hexyl ketone, and vinyl isopropyl ketone.
Examples of the polyfunctional monomer may include: diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2'-bis[4-acryloxydiethoxy)phenyl]propane, trimethylpropane triacrylate, tetramethylmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis[4-(methacryloxydiethoxy)-phenyl]propane, 2,2'-bis[4-(methacryloxypolyethoxy)-phenyl]propane, trimethylpropane trimethacrylate, tetramethylmethane tetramethacrylate, divinylbenzene, divinylnaphthalene, and divinyl ether.
The polymerization initiator used for polymerization of the above-mentioned polymerizable monomer may be an oil-soluble initiator and/or a water-soluble initiator. Examples of the oil-soluble initiator may include: azo compounds, such as 2,2'-azobisisobutyronitrile, 2,2'-azobis-2,4-dimethyl-valeronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), and 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile; and peroxide initiators, such as acetylcyclohexylsulfonyl peroxide, diisopropyl peroxycarbonate, decanoyl peroxide, lauroyl peroxide, stearoyl peroxide, propionyl peroxide, acetyl peroxide, t-butyl peroxy-2-ethylhexanoate, benzoyl peroxide, t-butyl peroxyisobutyrate, cyclohexanone peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, and cumeme hydroperoxide.
In case where the toner according to the present invention is produced through the suspension polymerization, toner particles may be produced directly in the following manner. Into a polymerizable monomer, a low-softening point substance such as wax, a colorant, a polymerization initiator, a crosslinking agent and another optional additive are added and uniformly dissolved or dispersed by a homogenizer or an ultrasonic dispersing device, to form a polymerizable monomer composition, which is then dispersed and formed into particles in a dispersion medium containing a dispersion stabilizer by means of an ordinary stirrer, a homomixer or a homogenizer preferably under such a condition that droplets of the polymerizable monomer composition can have a desired particle size of the resultant toner particles by controlling stirring speed and/or stirring time. Thereafter, the stirring may be continued in such a degree as to retain the particles of the polymerizable monomer composition thus formed and prevent the sedimentation of the particles. The polymerization may be performed at a temperature of at least 40� C., generally 50-90� C., preferably 55-85� C. The temperature can be raised at a later stage of the polymerization. It is also possible to subject a part of the aqueous system to distillation in a latter stage of or after the polymerization in order to remove the yet-unpolymerized part of the polymerizable monomer and a by-product which can cause an odor in the toner fixation step. After the reaction, the produced toner particles are washed, filtered out, and dried. In the suspension polymerization, it is generally preferred to use 300-3000 wt. parts of water as the dispersion medium per 100 wt. parts of the monomer composition.
The shape factor SF-1 referred to herein is based on values measured in the following manner. Images of 100 toner particles observed through a field emission scanning electron microscope (FE-SEM) ("S-800", available from Hitachi Seisakusho K. K.) at a magnification of, e.g., 500 are sampled at random, and the image data of the toner images are inputted for analysis into an image analyzer (e.g., "Luzex III", available from Nireco K. K.) through an interface, whereby the shape factor SF-1 is calculated by the following equation:
Thereafter, a magenta toner image (second color toner image), a cyan toner image (third color toner image) and a black toner image (fourth color toner image) are similarly and successively transferred in superposition onto the intermediate transfer member 5 to form thereon a synthetic color toner image corresponding to the objective color image.
At this time, the secondary transfer residual toner remaining on the intermediate transfer member 5 without being transferred to the transfer material P is frequently charged to a polarity (positive) reverse to the normal polarity (negative). However, this does not mean that all the secondary transfer residual toner is charged to a reverse polarity (positive), but a portion thereof has no charge due to neutralization or retains a negative polarity.
Measurement is performed by using a visco-elasticity measurement apparatus ("Rheometer RDA-II", available from Rheometrics Co.) with respect to a storage modulus G', a loss modulus G", a temperature (Tc) of intersection between G' and G", and tan (δ) in a temperature range of 30-200� C.
Measurement temperature: Increased at a rate of 2� C./min, from 25� C. to 250� C.
Measurement is performed by using a differential scanning calorimeter ("DSC-7", available from Perkin-Elmer Corp.) according to ASTM D-3418-82. A sample in an amount of 2-10 mg, preferably ca. 5 mg, is accurately weighed. The sample is placed on an aluminum pan and subjected to measurement in a temperature range of 30-200� C. at a temperature-raising rate of 10� C./min in a normal temperature/normal humidity environment. A heat-absorption main peak temperature (Tm.p.) and a half-value width (a temperature width at a half of the heat-absorption main peak, denoted by W1/2) are recorded.
Gloss is measured by using a handy gloss meter ("Gloss Meter PG-3D", available from Nippon Denshoku Kogyo K. K.) at a light incident angle of 75 deg.
Sample toner particles are sufficiently dispersed in a cold-setting epoxy resin, which is then hardened for 2 days at 40� C. The hardened product is dyed with triruthenium tetroxide optionally together with triosmium tetroxide and sliced into thin flakes by a microtome having a diamond cutter. The resultant thin flake sample is observed through a transmission electron microscope to confirm a sectional structure of toner particles. The dyeing with triruthenium tetroxide may preferably be used in order to provide a contrast between the low-softening point compound and the outer resin by utilizing a difference in crystallinity therebetween.
The agglomeratability of a sample toner is measured by using a powder tester (available from Hosokawa Micron K. K.). On a vibration table, a 400 mesh-sieve, a 200 mesh-sieve and a 100 mesh-sieve are set in superposition in this order, i.e., so that the 100-mesh sieve having the largest opening is placed at the uppermost position. On the set sieves, 5 g of a sample toner is placed, and the sieves are vibrated for 25 sec at an input voltage to the vibration table of 15 volts. Then, the weights of the toner remaining on the respective sieves are measured to calculate the agglomeratability according to the following formula:
Agglomeratability (%)=(a/5+(b/5)�0.6+(c/5)�0.2)�100,
4) The solution in the flask is titrated with a 0.1N-KOH alcohol solution from a buret.
Acid value=(S-B)�f�5.61/W,
Ca. 10 g of a sample toner is placed in a 100 cc-plastic cup and left standing for 3 days at 50� C. The state of the toner is then observed with eyes and evaluated according to the following standard.
EXAMPLE ______________________________________Styrene monomer         165    wt. partsn-Butyl acrylate monomer                          wt. partsPhthalocyanine pigment         wt. parts4(C.I. Pigment Blue 15:3)Linear polyester resin         wt. parts0(polycondensation between polyoxypropylene-                   2       wt. partsadducted bisphenol A and phthalic acid;AV (acid value) = 8 mg KOH/g)Dialkyl salicylic acid aluminum compoundDivinylbenzene                 wt. parts      0.5Ester wax                      wt. parts            30(ester between C22 -alkyl carboxylicacid and C22 -alkyl alcohol (Tmp (DSCmain peak) = 75� C., W1/2  (half-valuewidth) = 3� C.)______________________________________
The above ingredients were subjected to dispersion for 3 hours by an attritor, and then 3 wt. parts of lauroyl peroxide (polymerization initiator) was added thereto to formulate a polymerizable monomer composition, which was then charged into an aqueous medium at 70� C. comprising 1200 wt. parts of water and 7 wt. parts of tricalcium phosphate and subjected to formation of particles under stirring for 10 min. by a TK-type homomixer at 10,000 rpm. Then, the homomixer was replaced by a propeller stirring blade, which was stirred at 60 rpm for 10 hours of polymerization. After completion of the polymerization, dilute hydrochloric acid was added to the system to remove the calcium phosphate. Then, the polymerizate was washed and dried to obtain cyan toner particles having a weight-average particle size (D4)=6.5 μm. As a result of microscopic observation of section, the resultant cyan toner particles showed a structure as shown in FIG. 7 wherein the low-softening point substance (A) was coated with the outer shell (B).
Cyan Toner 1 showed SF-1=105, comprised ca. 12 wt. parts (ca. 12 wt. % of the toner) of ester wax per 100 wt. parts of binder resin comprising styrene/n-butyl acrylate copolymer crosslinked with divinylbenzene an d linear polyester resin, and had a THF-insoluble content (THF ins.) of ca. 10 wt. % (based on the binder).
COMPARATIVE EXAMPLE 1 Cyan Toner 2 was prepared in the same manner as in Example 1 except that the ester wax was replaced by paraffin wax (Tmp=63� C., W1/2 =40� C.) and the divinylbenzene was omitted.
The binder resin of Cyan Toner 2 was non-crosslinked and had no THF-insoluble content. In the viscoelasticity measurement, Cyan Toner 2 showed a remarkable lowering in viscosity and it was impossible to measure the viscoelasticities G' and G" above 140� C. The properties of Cyan Toner 2 are also shown in Table 1 together with those of Cyan Toner 1 and other toners.
COMPARATIVE EXAMPLE 2 Cyan Toner 3 was prepared in the same manner as in Example 1 except that the ester wax was replaced by paraffin wax (Tmp.=63� C., W1/2 =40� C.).
Cyan Toner 3 showed temperature-dependent viscoelasticities including storage modulus G', loss modulus G" and tan (δ) as shown in FIG. 3. Cyan Toner 3 showed a (G'60 /G'80) ratio of ca. 20, thus showing a smaller change in G' on temperature increase from 60� C. to 80� C.
COMPARATIVE EXAMPLE 3 Cyan Toner 4 was prepared in the same manner as in Example 1 except that the ester wax was replaced by polypropylene wax ("Viscol 660P", mfd. by Sanyo Kasei K. K.; Tmp.=137� C., W1/2 =7� C.).
COMPARATIVE EXAMPLE 4 Cyan Toner 5 was prepared in the same manner as in Example 1 except that the amount of the ester wax was changed to 5 wt. parts.
COMPARATIVE EXAMPLE 5 Cyan Toner 6 was prepared in the same manner as in Example 1 except that the amount of the ester wax was changed to 100 wt. parts.
COMPARATIVE EXAMPLE 6 Cyan Toner 7 was prepared in the same manner as in Example 1 except that the amount of the divinylbenzene was changed to 2 wt. parts.
COMPARATIVE EXAMPLE ______________________________________Styrene/n-butyl acrylate/                  100    wt. partsdivinylbenzene copolymer(Mw � 1.63 � 105, main peak molecularweight (MW peak) = 2.25 � 104, THFins =13.5 wt. %)Linear polyester resin         wt. parts5(Same as in Example 1)Dialkylsalicylic acid aluminum compound                     1   wt. partEster wax (Same as in Example 19                        3                         wt. parts______________________________________
The above ingredients were sufficiently blended by a Henschel mixer and melt-kneaded through a twin-screw extruder at ca. 130� C., followed by cooling, coarse crushing by a hammer mill into ca. 1-2 mm, pulverization by an air jet pulverizer and classification to recover cyan toner particles having D4 (weight-average particle size) of 7.5 μm.
COMPARATIVE EXAMPLE 8 Cyan Toner 9 was prepared in the same manner as in Comparative Example 7 except that the amount of the ester wax was increased to 15 wt. parts.
TABLE 1__________________________________________________________________________    Cyan  G'60       G'80 G'155                      G'190 G"40                                      G"max                                             tan(&#948;)                                                  D4    toner  (dyn/cm2)       (dyn/cm2)            G'60 /G'80                 (dyn/cm2)                      (dyn/cm2)                           G'155 /G'190                                 (dyn/cm2)                                      (dyn/cm2)/�                                             max/� C.                                                  (&#956;m)                                                      SF-1__________________________________________________________________________Ex.1   1  7.1 � 108       3.5 � 106            203.0                 1.3 �  104                      3.6 � 103                           3.6   1.1 � 109                                      1.8 � 109 /50.5                                             3.2/69                                                  6.5 105Comp.Ex.1     2   9.2 � 107          3.9 � 106                23.6                  --  --   --      6.8 � 108                                      --         1.                                                   6.5                                                       1042     3   8.1 � 107         4.2 � 106               19.3                   1.6 � 104                        2.1 � 103                                7.6                                     6.2 � 108                                       --       2.1                                                   6.5                                                       1043     4   1.5 � lO9          2.1 � 107                71.4                   6.1 � 104                        5.3 � 104                              1.1                                     1.2 � 109                                      2.3 � 109 /67                                                2.9                                                   7.8                                                       1314     5   6.3 � 109          9.4 � 106                67.0                   3.5 � 104                        5.7 � 103                              6.1                                     1.0 � l09                                      2.0 � 109 /66                                                2.9                                                   6.4                                                       1055     6   2.1 � 108         2.9 � 106               72.4                   5.5 � 103                        8.7 � 102                                6.3                                     7.3 � 108                                       --                                             1.8/63                                                   8.2                                                       1326     7   7.7 � 108         1.3 � 107               59.2                   5.4 � 104                        3.8 � 104                                1.4                                     1.2 � 109                                      2.0 � 109 /53                                                2.0                                                   6.6                                                       1057     8   2.5 � 108         3.8 � 106               65.8                   8.4 � 103                        9.1 � 102                                9.2                                     8.1 � 108                                             --                                                  1                                                   7.53                                                       1658     9   8.5 � 108         1.2 � 107               70.8                   9.8 � 103                        1.9 � 103                                5.2                                     9.1 � 108                                      9.8 � 108 /49                                                2.1                                                   7.4                                                       163__________________________________________________________________________                                  Binder resin GPC peak or shoulder                                  molecular weight**                                  (�104)                            THFins Sub-peak or                                                  Dag*lder                                                      Anti-                            (wt. %)                                  Main peak                                        &#8807;105                                                  (%) block__________________________________________________________________________                       Ex.                       1    9.6   2.2   15 (S),                                             110 (S)                                                  4.8 A                       Comp.                       Ex.                       1    0     1.8   --        65.0                                                      D                       2    9.6   2.25  14 (S),                                             100 (S)                                                  40.0                                                      D                       3    9.3   2.1   16 (S),                                             120 (S)                                                  28.0                                                      C                       4    10.4  2.3   15 (S),                                             115 (S)                                                  4.3 A                       5    8.5    1.9  13 (S),                                             110 (S)                                                  35.0                                                      C                       6    47.0  3.2   25 (S)    5.3 A                       7    0     2.1   75 (S)    54.0                                                      C                       8    0     2.1   74 (S)    38.0                                                      C__________________________________________________________________________ *: Dag = agglomeratability **: (S) means the molecular weight of a shoulder.
EXAMPLE 2 Cyan Toner 1 was charged in a developing device 4-3 (apparatus unit), incorporated in an image forming apparatus shown in FIG. 5 and subjected to an image formation test according to a mono-color mode. During a continuous image formation on 5000 sheets, good cyan-colored fixed images were formed at a high density and without fog. After the 5000 sheets of the continuous image formation test, the toner application roller 18, the developing sleeve 16 and the elastic blade 19 were free from toner melt-sticking, thus showing a good continuous image forming characteristic. Further, oilless fixation was performed without applying dimethylsilicone oil onto the heating roller 14, no offset was observed. Further, the fixing temperature was varied in the range of 160-190� C., whereby little change in gloss value was observed. The results are inclusively shown in Table 2 together with those of Examples appearing hereinafter.
COMPARATIVE EXAMPLES 9-16 Image forming tests were formed in the same manner as in Example 2 except for using Cyan Toners 2-9 instead of Cyan Toner 1.
The image density of a solid image portion (a portion showing a gloss in the range of 25-35 as measured by a gloss meter ("PG-3D", available from Nippon Denshoku Kogyo K. K.)) is measured by using a Macbeth reflection densitometer (available from Macbeth Co.).
Based on reflectance values measured by using a reflectance meter ("REFLECTOMETER MODEL TC-6DS", available from Tokyo Denshoku K. K.) while using an amber filter in case of cyan toner images, fogs are calculated according to the following equation. A smaller value means a lower degree of fog.
Fog (reflectance) (%)=[reflectance of standard paper (%)]-[reflectance of non-image portion of a sample (%)]
A heat-pressure fixing device including a fluorine resin-surfaced heating roller 14 and a pressure roller 15 is used for fixation while varying the temperatures of the heating roller and the pressure roller at a temperature-controlled increment of 5� C. The fixed images at the respective fixing temperatures are rubbed two times (one reciprocation) with a lens-cleaning paper under a load of 50 g/cm2 and a lowest fixing temperature giving an image density lowering of 10% or less after the rubbing is taken as a fixing initiation temperature (TFI (� C.)).
The fixing temperature is successively raised at an increment of 5� C., and a maximum temperature at which the fixing is performed without causing offset according to observation with eyes is taken as a higher offset-free temperature (TH.OFF (� C.)).
TABLE 2__________________________________________________________________________  Image density          Fog                       Soiling within developing drive      After   After                 TonerCyan       5000    5000                  TFI *                     TH.OFF *                         Gloss of final image                                    appln.                                        Developing                                              ElasticToner  Initial      sheets          Initial              sheets                  (� C.)                     (� C.)                         at 160� C.                               at 190� C.                                    roller                                        sleeve                                              blade__________________________________________________________________________Ex.2   1  1.50      1.55          0.5 0.7 140                     210 11    18   A   A     AComp.Ex.9   2  1.25      0.91          3.2 5.8 140                     180 15    --   C   C     C10  3  1.30      0.98          2.7 5.3 150                     210 11    25   C   C     C11  4  1.45      1.35          0.8 2.8 180                     210 --    15   A   B     B12  5  1.51      1.53          0.5 0.6 160                     180  8    --   A   A     A13  6  1.38      1.15          1.8 4.8 140                     220 12    35   B   C     C14  7  1.56      1.50          0.6 0.9 190                     220 --     8   A   A     A15  8  1.28      0.97          3.0 5.6 140                     200 10    40   B   C     C16  9  1.34      1.20          2.5 4.6 160                     190  5    38   B   C     B__________________________________________________________________________ *TFI : Fixing initiation temperature (� C.) TH.OFF : Higher offset free temperature (� C.)
EXAMPLE 3 Yellow Toner 1 was prepared in the same manner as in Example 1 except that a yellow colorant (C.I. Pigment Yellow 173) was used instead of the phthalocyanine pigment. The properties thereof are shown in Table 3.
COMPARATIVE EXAMPLES 17-24 Yellow Toners 2-9 were prepared in the same manner as in Comparative Examples 1-8, respectively, except that a yellow colorant (C.I. Pigment Yellow 173) was used instead of the phthalocyanine pigment. The properties thereof are also shown in Table 3.
EXAMPLE 4 Magenta Toner 1 was prepared in the same manner as in Example 1 except that a magenta colorant (C.I. Pigment Red 122) was used instead of the phthalocyanine pigment. The properties thereof are shown in Table 4.
COMPARATIVE EXAMPLES 25-32 Magenta Toners 2-9 were prepared in the same manner as in Comparative Examples 1-8, respectively, except that a magenta colorant (C.I. Pigment Red 122) was used instead of the phthalocyanine pigment. The properties thereof are also shown in Table 4.
EXAMPLE 5 Black Toner 1 was prepared in the same manner as in Example 1 except that a black colorant (carbon black) was used instead of the phthalocyanine pigment. The properties thereof are shown in Table 5.
COMPARATIVE EXAMPLES 33-40 Black Toners 2-9 were prepared in the same manner as in Comparative Examples 1-8, respectively, except that a black colorant (carbon black) was used instead of the phthalocyanine pigment. The properties thereof are also shown in Table 5.
TABLE 3__________________________________________________________________________    Yel-    low  G'60       G'80 G'155                      G'190 G"40                                      G"max                                             tan(&#948;)                                                  D4    toner  (dyn/cm2)       (dyn/cm2)            G'60 /G'80                 (dyn/cm2)                      (dyn/cm2)                           G'155 /G'190                                 (dyn/cm2)                                      (dyn/cm2)/�                                             mac/� C.                                                  (&#956;m)                                                      SF-1__________________________________________________________________________Ex.3    1 7.2 � 108         3.6 � 106            200.0                   1.3 � 104                      3.7 � 103                           3.5    1.1 � 109                                         1.9 � 109                                              3.1/6                                                      106Comp.Ex.17    2  9.1 � 107         3.8 � 106             23.9                    --                                   6.8 � 108                                      --                                                      105.5/7718    3  8.2 � 107         4.4 � 106             18.6                   1.8 � 104                      2.0 � 103                            9.0  6.1 � 108                                      --                                             2.1/83                                                      10419    4  1.2 � 109         2.0 � 107             60.0                   6.0 � 104                      5.6 � 104                            1.1  1.2 � 109                                      2.4 � 109 /67                                                2.8                                                      13320    5  6.3 � 109         9.3 � 107             67.7                   3.7 � 104                      5.6 � 103                            6.6  1.1 � 109                                      1.9 � 109 /66                                                2.9                                                      10421    6  2.0 � 108         2.9 � 106             69.0                   5.6 � 103                      8.9 � 102                            6.3  7.5 � 108                                      --                                             1.8/63                                                      13522    7  7.5 � 108         1.5 � 106             50.0                   5.4 � 104                      3.9 � 104                            1.4  1.2 � 109                                      2.1 � 109 /55                                                2.1                                                      10423    8  2.4 � 108         3.7 � 106             64.9                   8.5 � 103                      9.0 � 102                            9.4  8.2 � 108                                      --                                             1.6/65                                                   7.4                                                      16624    9  8.6 � 108         1.3 � 107             66.2                   9.7 � 103                      1.7 � 103                            5.7  9.2 � 108                                      9.9 � 108 /50                                                2.0                                                      168__________________________________________________________________________                                  Binder resin GPC peak or shoulder                                  molecular weight**                                  (�104)                            THFins Sub-peak or                                                  Dag*lder                                                      Anti-                            (wt. %)                                  Main peak                                        &#8807;105                                                  (%) block__________________________________________________________________________                       Ex.                       3     10.3   2.1  13 (S),  115                                                  4.5    A                       Comp.                       Ex.                       17     0     1.9   --        66.                                                            D                       18     9.9  2.0   12 (S), 12                                                   43.0                                                              D                       19    10.7  2.3   15 (S), 11                                                    25.                                                             C                       20    11.3  2.2   14 (S), 11                                                    4.1                                                              A                       21     6.5  1.8   13 (S), 12                                                     38                                                            C                       22    45.0  3.3   27 (S)          A    6.6                       23     0      2.1                                         78 (S)          C    58.0                       24     0      2.1                                         76 (S)__________________________________________________________________________                                                      C    40.0
TABLE 4__________________________________________________________________________    Ma-    genta  G'60       G'80 G'155                      G'190 G"40                                      G"max                                             tan(&#948;)                                                  D4    toner  (dyn/cm2)       (dyn/cm2)            G'60 /G'80                 (dyn/cm2)                      (dyn/cm2)                           G'155 /G'190                                 (dyn/cm2)                                      (dyn/cm2)/�                                             mac/� C.                                                  (&#956;m)                                                      SF-1__________________________________________________________________________Ex. 4   1 6.9 � 108         3.3 � 106            209.0                   1.1 � 104                      3.5 � 103                           3.1    1.1 � 109                                         1.9 � 104                                              3.3/6                                                      103Comp.Ex.25    2    9.0 � 107       3.5 � 106               25.7                  --             6.0 � 108                                      --                                             1.5/78                                                   6.1                                                       10526    3    8.3 � 107       4.0 � 106             20.8                    1.4 � 104                      1.8 � 103                            7.8   6.4 � 108                                      --                                             2.2/80                                                   6.2                                                       10427    4    1.3 � 109       1.9 � 107             68.4                    5.8 � 104                      5.3 � 104                            1.1   1.0 � 109                                      2.4 � 109 /67                                             2.8/75                                                   7.6                                                       13228    5    6.6 � 109       1.0 � 107             660.0                   3.7 � 104                      5.6 � 103                            6.6   1.3 � 109                                      2.1 � 109 /65                                             2.9/72                                                   6.5                                                       10329    6    2.0 � 108       2.7 � 106              74.0                   5.6 � 103                      8.5 � 102                             6.6 7.5 � 108                                          --       8.0                                                       1356530    7    7.9 � 108       1.5 � 107             51.3                    5.5 � 104                      3.7 � 104                            1.5   1.3 � 109                                      1.9 � 109 /54                                             2.2/74                                                   6.4                                                       10531    8    2.6 � 108       3.6 � 106             72.2                    8.0 � 103                      8.9 � 102                            9.0   8.0 � 108                                         --        7.3                                                       1646332    9    8.7 � 108       1.4 � 107              62.1                   9.5 � 103                      1.3 � 103                             7.3 8.9 � 108                                      9.5 � 108 /47                                             2.0/68                                                   7.1                                                       162__________________________________________________________________________                                  Binder resin GPC peak or shoulder                                  molecular weight**                                  (�104)                            THFins Sub-peak or                                                  Dag*lder                                                      Anti-                            (wt. %)                                  Main peak                                        &#8807;105                                                  (%) block__________________________________________________________________________                       Ex.                       4     7.6  2.3    16 (S),  100                                                  6.1    A                       Comp.                       Ex.                       25    0       1.9                                           --                                                      D3.0                       26    5.8   2.15  17 (S),    39.                                                        D                       27    9.1   2.1    18 (S),   30.                                                        C)                       28    10.5 2.2     14 (S),    5.                                                        A)                       29    6.7   1.8    15 (S),   38.                                                        C)                       30    44.0 3.25   32 (S)         A       6.0                       31     0     2.2   80 (S)        C       59.0                       32     0     2.2   82 (S)__________________________________________________________________________                                                      C       41.0
TABLE 5__________________________________________________________________________    Black  G'60       G'80 G'155                      G'190 G"40                                      G"max                                             tan(&#948;)                                                  D4    toner  (dyn/cm2)       (dyn/cm2)            G'60 /G'80                 (dyn/cm2)                      (dyn/cm2)                           G'155 /G'190                                 (dyn/cm2)                                      (dyn/cm2)/�                                             mac/� C.                                                  (&#956;m)                                                      SF-1__________________________________________________________________________Ex.5     1  6.8 � 108       3.2 � 106               213.0                  1.4 � 104                         3.7 � 103                            3.8  1.1 � 109                                       1.9 � 109 /51                                                3.4                                                   6.1                                                       103Comp.Ex.33    2    9.3 � 107         3.9 � 106             25.8                  --             6.2 � 8                                        --                                             1.6/78                                                   6.3                                                       10334    3    8.0 � 107         4.5 � 106             17.8                  1.5 � 104                         2.4 � 103                            6.3  6.0 � 108                                      --                                             1.9/80                                                   6.3                                                       10335    4    1.9 � 109         2.5 � 107             76.0                  6.0 � 104                         5.8 � 104                            1.0  1.3 � 109                                       2.2 � 109 /66                                             2.7/78                                                   7.7                                                       13736    5    7.0 � 109         9.5 � 106             73.7                  3.9 � 104                         5.1 � 103                            7.6  1.1 � 109                                       2.4 � 109 /65                                             2.5/75                                                   6.2                                                       10437    6    2.0 � 108         2.7 � 106             74.1                  5.0 � 103                         8.0 � 102                            7.1  6.9 � 108                                       --                                                      108/6438    7    8.0 � 108         1.5 � 107             53.3                  5.5 � 108                         3.1 � 104                            1.8  1.3 � 109                                       2.0 � 109 /55                                             1.8/73                                                   6.4                                                       10539    8    2.5 � 108         4.0 � 106             62.5                  8.6 � 103                         9.5 � 102                            9.1  8.1 � 108                                          --       7.4                                                       1656240    9    8.9 � 108         1.5 � 107             59.3                  1.0 � 104                         1.8 � 103                            5.6  9.5 � 108                                       9.8 � 109 /48                                             2.0/68                                                   7.4                                                       166__________________________________________________________________________                                  Binder resin GPC peak or shoulder                                  molecular weight**                                  (�104)                            THFins Sub-peak or                                                  Dag*lder                                                      Anti-                            (wt. %)                                  Main peak                                        &#8807;105                                                  (%) block__________________________________________________________________________                       Ex.                       5      5.8  2.0    15 (S), 1                                                   5.2S                                                         A                       Comp.                       Ex.                       33   0       1.7  --                                                  60.0                                                      D                       34   6.4   2.1     12 (S), 1                                                      D2.0                       35   7.2   1.95    14 (S), 110                                                  27.0                                                      C                       36   7.8   2.2   15 (S), 120                                                  4.8 A                       37   4.0   1.8   14 (S), 110                                                  42.0                                                      C                       38   43.0  3.5     24 (S)         A3                       39   0       2.15                                         83 (S)                                                      C5.0                       40   0       2.2   83 (S)                                                      C4.0__________________________________________________________________________
EXAMPLE 6 Yellow Toner 1, Magenta Toner 1, Cyan Toner 1 and Black Toner 1 were charged in developing devices 4-1, 4-2, 4-3 and 4-4, respectively, and incorporated in the image forming apparatus similar to the one used in Example 1 to effect a full-color mode image forming test. The results are shown in Table 6.
COMPARATIVE EXAMPLES 41-48 Full-color image forming tests were performed in the same manner as in Example 6 except for using Yellow Toners 2-9, Magenta Toners 2-9, Cyan Toners 2-9 and Black Toners 2-9, respectively, in combination. The results are also shown in Table 6.
TABLE 6__________________________________________________________________________Toner               Color Gloss     TFI                                  TH.OFF  Yellow   Magenta        Cyan           Black               mixability*                     at 160� C.                          at 190� C.                               (� C.)                                  (� C.)__________________________________________________________________________Ex.6     1 1       11    A     17   25  150                                  210Comp.Ex.41   2   2      2  2               A       35   --  155                                  17542  3    3    3 3     A     15   40  155                                  20043  4    4    4 4     C      --                            15  190                                  21044  5    5    5 5     C     10 --    160                                  18045  6    6    6 6     A     25   43  150                                  21046  7    7    7 7     C     --   10  190                                  22047  8    8    8 8     A     18   48  150                                  19048  9    9    9 9     B     10   --  160                                  180__________________________________________________________________________ *Colormixing characteristic was evaluated at three level by comparison with the original image by eye observation: A: good, B: average, C: poor.
EXAMPLES 7-12 Cyan Toners 10-15 were prepared in the same manner as in Example 1 except for changing the species of polyester resin, the amount of divinylbenzene and the species of wax. The properties of the toner are shown in Table 7.
EXAMPLES 13-18 Image forming tests were performed in the same manner as in Example 2 except for using Cyan Toners 10-15, respectively, instead of Cyan Toner 1. The results are shown in Table 8.
TABLE 7__________________________________________________________________________    Cyan  G'60       G'80 G'155                      G'190 G"40                                      G"max                                             tan(&#948;)                                                  D4Ex. toner  (dyn/cm2)       (dyn/cm2)            G'60 /G'80                 (dyn/cm2)                      (dyn/cm2)                           G'155 /G'190                                 (dyn/cm2)                                      (dyn/cm2)/�                                             max/� C.                                                  (&#956;m)                                                      SF-1__________________________________________________________________________ 7  10 3.9 � 108       2.8 � 106            140  1.5 � 104                      4.0 � 103                           3.8   1.1 � 109                                      2.2 � 109 /55                                             3.5/74                                                  5.9 102 8   11     3.5 � 1010        1.0 � 108             350   1.0 � 104                        4.2 � 103                             2.4    9.9 � 108                                       1.8 � 109 /58                                               3.1/65                                                  6.2  107 9  12 3.0 � 1010       1.2 � 108            250  3.8 � 104                      3 � 104                           1.3   1.3 � 109                                      2.7 � 109 /61                                             3.3/75                                                  6.8 10510  13 5.3 � 109       2.9 � 107            180  2.5 � 104                      7.8 � 103                           3.2   1.2 � 109                                      1.9 � 109 /53                                             1.3/80                                                  6.6 11311  14 8.2 � 108       6.6 � 106            125  4.7 � 104                      1.0 � 104                           4.7   1.1 � 109                                      2.5 � 109 /62                                             3.0/78                                                  6.5 11012  15    4.6 � 108          2.5 � 106             185  4.9 � 103                        1.0 � 103                              4.9                                 1.0 � 109                                       1.6 � 109 /65                                               3.2/                                                      105__________________________________________________________________________                                  Binder resin GPC peak or shoulder                                  molecular weight**                                  (�104)                            THFins Sub-peak or                                                  Dag*lder                                                      Anti-                       Ex.  (wt. %)                                  Main peak                                        &#8807;105                                                  (%) block__________________________________________________________________________                       7    15.0  2.5   50 (S)    13.0                                                      B                       8    3.0   1.5      35 (S)    18                                                        B                       9    20.0  2.8   25 (S), 100                                                  9.8 A                       10   18.0  2.3   14 (S), 110                                                  3.1 A                       11   25.0  2.9   50 (S)    7.8 A                       12   0.5   2.5   25 (S), 100                                                  5.6 A__________________________________________________________________________
TABLE 8__________________________________________________________________________Image density       Fog                      Soiling within developing drive   After  After                 TonerCyan    5000   5000              TFI *                  TH.OFF *                      Gloss of final image                                 appln.                                    Developing                                          ElasticEx.  tonerInitial   sheets       Initial          sheets              (� C.)                  (� C.)                      at 160� C.                           at 190� C.                                roller                                    sleeve                                          blade__________________________________________________________________________13  10 1.53   1.45       1.0          1.8 145 210 13   20   A   A     A14   111.56     1.38          1.5            2.3              145   200                      14     25  A     B      B15   121.58     1.52          0.7            1.0              145   220                       8     15  A     A      A16   131.53     1.57          0.5            0.8              155   210                      10     25  A     A      A17   141.45     1.50          1.2            2.4              155   220                       7     12  A     A      A18   151.56     1.54          0.8            1.2              140   200                      10     25  A     A      A__________________________________________________________________________
EXAMPLE 19 ______________________________________Styrene monomer        180    wt. partsn-Butyl acrylate monomer                         wt. partsYellow pigment (Pigment Yellow)                       18                         wt. partsSaturated polyester resin                         wt. partsDialkylsalicylic acid chromium compound                  2      wt. partsDivinylbenzene                wt. parts       0.3Tetraethylene glycol dimethacrylate                    0.2      wt. partsEster wax (Tmp = 74� C., W1/2  4� C.)                  30     wt. parts______________________________________
The above ingredients were subjected to dispersion for 3 hours by an attritor, and then 5 wt. parts of 2,2'-azobisisobutyronitrile (polymerization initiator) was added thereto to formulate a polymerizable monomer composition, which was then charged into an aqueous medium at 60� C. comprising 1200 wt. parts of water and 7 wt. parts of sodium polyacrylate and subjected to formation of particles under stirring for 15 min. by a TK-type homomixer at 12,000 rpm. Then, the homomixer was replaced by a propeller stirring blade, and the system temperature was increased to 70� C. for 10 hours of polymerization under stirring at 60 rpm. The polymerizate particles in suspension showed a weight-average particle size (D4) of 1 μm.
Then, while the suspension liquid was stirred, the pH thereof was adjusted to 4.6 and the temperature was adjusted at 85� C. The pH and the temperature were maintained for 7 hours to effect association of the particles. The resultant particles were washed with water and dried to obtain yellow toner particles having a weight-average particle size (D4) of 6.1 μm. As a result of microscopic observation, the toner particles showed a sea-island structure including a low-softening point substance (A) dispersed within and coated with an outer shell resin (B) as shown in FIG. 8.
EXAMPLE 20 ______________________________________Styrene monomer         170    wt. partsn-Butyl acrylate monomer                          wt. partsMagenta pigment (Permanent Red)                        13                          wt. partsUnsaturated polyester resin                          wt. partsDialkylsalicylic acid aluminum compound                   2      wt. partsDivinylbenzene                 wt. parts       0.2Polyethylene wax (Tmp = 128� C., W1/2 = 38� C.)                    1     wt. partsEster wax (Tmp = 72� C., W1/2  = 5� C.)                   19     wt. parts______________________________________
The above ingredients were subjected to dispersion for 3 hours by an attritor, and then 4.5 wt. parts of 2,2'-azobis-2,4-dimethylvaleronitrile (polymerization initiator) was added thereto to formulate a polymerizable monomer composition, which was then charged into an aqueous medium at 65� C. comprising 1200 wt. parts of water and 8 wt. parts of tricalcium phosphate and subjected to formation of particles under stirring for 9 min. by a TK-type homomixer at 9,000 rpm. Then, the homomixer was replaced by a propeller stirring blade, which was stirred at 70 rpm for 9 hours of polymerization. After completion of the polymerization, dilute hydrochloric acid was added to the system to remove the calcium phosphate. Then, the polymerizate was washed and dried to obtain magenta toner particles having a weight-average particle size (D4)=6.2 μm.
EXAMPLE ______________________________________ Styrene monomer               wt. parts    195n-Butyl acrylate monomer                          wt. partsMagenta pigment (Permanent Red)                         19                            wt. partsLow-molecular weight polyester                          10                                wt. partsDialkylsalicylic acid aluminum compound                   2      wt. partsDivinylbenzene                 wt. parts       1.5Ester wax (Tmp = 79� C., W1/2  = 3� C.)                     20       wt. parts______________________________________
The above ingredients were subjected to dispersion for 3 hours by an attritor, and then 3 wt. parts of lauroyl peroxide (polymerization initiator) was added thereto to formulate a polymerizable monomer composition, which was then charged into an aqueous medium at 70� C. comprising 1200 wt. parts of water and 7 wt. parts of tricalcium phosphate and subjected to formation of particles under stirring for 8 min. by a TK-type homomixer at 10,000 rpm. Then, the homomixer was replaced by a propeller stirring blade, which was stirred at 60 rpm for 10 hours of polymerization. After completion of the polymerization, dilute hydrochloric acid was added to the system to remove the calcium phosphate. Then, the polymerizate was washed and dried to obtain magenta toner particles having a weight-average particle size (D4)=6.7 μm.
EXAMPLE 22 ______________________________________ Styrene monomer        145     wt.partsn-Butyl acrylate monomer                          wt. partsPhthalocyanine pigment                 wt. partsSaturated polyester resin                          wt. partsDialkylsalicylic acid aluminum compound                     2    wt. partsDivinylbenzene                 wt. parts        1.3Tetraethylene glycol dimethacrylate                     0.2  wt. partsEster wax (Tmp = 81� C., W1/2  = 5� C.)                      30  wt. parts______________________________________
The above ingredients were subjected to dispersion for 3 hours by an attritor, and then 5 wt. parts of 2,2'-azobisisobutyronitrile (polymerization initiator) was added thereto to formulate a polymerizable monomer composition, which was then charged into an aqueous medium at 60� C. comprising 1200 wt. parts of water and 7 wt. parts of sodium polyacrylate and subjected to formation of particles under stirring for 15 min. by a TK-type homomixer at 12,000 rpm. Then, the homomixer was replaced by a propeller stirring blade, and the system temperature was increased to 75� C. for 10 hours of polymerization under stirring at 60 rpm. The polymerizate particles in suspension showed a weight-average particle size of 1 μm. Then, while the suspension liquid was stirred, the pH thereof was adjusted to 4.6 and the temperature was adjusted at 85� C. The pH and the temperature were maintained for 7 hours to effect association of the particles. The resultant particles were washed with water and dried to obtain cyan toner particles having a weight-average particle size (D4) of 6.2 μm.
EXAMPLE 23 ______________________________________ Styrene monomer        165     wt. partsn-Butyl acrylate monomer                             wt. partsPhthalocyanine pigment            wt. partsLow-molecular weight polyester                          10                          wt. partsDialkylsalicylic acid chromium compound                   2      wt. partsDivinylbenzene                 wt. parts      1.5Amide wax (Tmp = 105� C., W1/2  = 30� C.)                   30     wt. parts______________________________________
The above ingredients were subjected to dispersion for 3 hours by an attritor, and then 3 wt. parts of lauroyl peroxide (polymerization initiator) was added thereto to formulate a polymerizable monomer composition, which was then charged into an aqueous medium at 70� C. comprising 1200 wt. parts of water and 10 wt. parts of tricalcium phosphate and subjected to formation of particles under stirring for 12 min. by a TK-type homomixer at 10,000 rpm. Then, the homomixer was replaced by a propeller stirring blade, which was stirred at 60 rpm for 10 hours of polymerization. After completion of the polymerization, dilute hydrochloric acid was added to the system to remove the calcium phosphate. Then, the polymerizate was washed and dried to obtain cyan toner particles having a weight-average particle size (D4)=6.4 μm.
In order to evaluate the low-temperature fixability of a toner, a fixing device of a digital copying machine ("GP-55", made by Canon K. K.) was taken out and re-modeled to be equipped with an external driver and a temperature controller so as to rotate the fixing rollers at a process speed of 50 mm/sec and control the fixing roller temperature in the range of 100-250� C. The fixing test was performed in a thermostatic chamber controlled at a temperature of 3-5� C. After confirming that the fixing rollers reached the chamber temperature, a power was supplied, and a fixing test was performed immediately after the heating roller (upper roller) reached 110� C. At this point of time, the pressure roller (lower roller) was at ca. 70� C. Then, while the heater was energized, the fixing rollers were rotated for 20 min., and then a fixing test was performed. At this time, the pressure roller temperature was ca. 90� C.
In order to evaluate the gloss stability of a toner, a fixed image sample at a fixing temperature of 155� C. was observed with eyes for evaluating a gloss lowering between ends and a difference from a fixed image sample at 190� C. Further, each toner was subjected to a continuous image forming test on 10,000 sheets by using a commercially available copying machine ("FC-330", made by Canon K. K.) together with a process cartridge (apparatus unit) for non-magnetic mono-component development, whereby a degree of gloss change between an average gloss value at an initial stage (on first to tenth sheets) and a gloss value at the end of continuous forming test was recorded.
TABLE 9______________________________________     ExamplesTest item   19       20     21     22   23______________________________________ G'60 /G'80       145       122   81     150  80G'155 /G'190            1.2  1.1    1.1    1.4   1.2Tc (� C.)                  69     87     38    611) Fixability        A           A     C      A     Bat 110� C.2) Gloss    A            A     A      A     Alowering3) Gloss    A            A     A      A     Adifference4) Gloss change       A            A     A      A     ArateAnti-blocking           B        B     B      C     B______________________________________
[Notes of Tables 9 and 10]
1) Fixability at 110� C.
Fixed images were rubbed two times (one reciprocation) with a lens cleaning paper ("dasper" available from Ozu Paper Co. Ltd.) under a load of 50 g/cm2, and a lowering in image density due to the rubbing was recorded for each fixed image. The above fixing test was performed for a fixed image obtained immediately after the heating roller reached 110� C. and for a fixed image obtained after 20 minutes of blank rotation of the fixing rollers for each toner sample to measure a change in lowered image density. For a series of sample toners (Examples 19-23 and Comparative Examples 37-41), the above test was preformed, and the maximum change of a sample among the samples was taken as the standard (100%). The other samples were rated at four ranks of A-D based on the relative change as follows:
A smaller value of the relative change means a smaller change between a density lowering between the fixed image obtained immediately after the heating roller temperature has reached 110� C. and the fixed image obtained after 20 min. of blank rotation, i.e., showing a good fixability (a toner's own fixability) from the initial stage after a power supply to the image forming apparatus.
A gloss difference between a fixed image sample at 155� C. and a fixed image sample at 190� C. was measured for each toner sample, and largest difference among the toner samples was taken as the standard (100%), and the other toner samples were rated according to the following standard based on a relative gloss difference.
COMPARATIVE EXAMPLE 49 A yellow toner having a weight-average particle size of 6.5 μm was prepared in the same manner as in Example 19 except for omitting the divinylbenzene used in Example 19.
COMPARATIVE EXAMPLE 50 A yellow toner having a weight-average particle size of 6.6 μm was prepared in the same manner as in Example 19 except for using polypropylene wax (Tmp=143� C., W1/2 =30� C.) instead of the ester wax used in Example 19.
COMPARATIVE EXAMPLE 51 A yellow toner having a weight-average particle size of 6.4 μm was prepared in the same manner as in Example 19 except for omitting the divinylbenzene and replacing the ester wax with polypropylene wax (Tmp=146� C., W1/2 =33� C.).
COMPARATIVE EXAMPLE 52 A yellow toner having a weight-average particle size of 6.9 μm was prepared in the same manner as in Example 19 except for omitting the divinylbenzene and tetraethylene glycol dimethacrylate used in Example 19.
COMPARATIVE EXAMPLE 53 A magenta toner having a weight-average particle size of 6.6 μm was prepared in the same manner as in Example 20 except for omitting the divinylbenzene and replacing the unsaturated polyester with saturated polyester.
TABLE 10______________________________________         Comparative      ExamplesTest item        49   50     51     52   53______________________________________  G'60 /G'80         101     71     74     80  114G'155 /G'190           18   1.05    9.5     22   26Tc (� C.)               58                  61     60     66   711) Fixability       B           D      C      C    Aat 110� C.2) Gloss    D           A      C      D    Dlowering3) Gloss    D           A      C      D    Ddifference4) Gloss change       D           A      C      D    DrateAnti-blocking          C        B      B      B    B______________________________________
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improved storage elastic modulus; prevents low temperature offset and high temperature offsetUS6586147 *Jul 9, 2001Jul 1, 2003Canon Kabushiki KaishaBinder resin, a colorant and a wax; toner has specific storage modulus or viscoelasticities; heat-pressure fixing means using no or only a limited amount of oil; offset resistanceUS6664016Jul 10, 2001Dec 16, 2003Canon Kabushiki KaishaUsed in imaging via development of electrostatic latent image or by toner jetting; exhibits high minuteness even with heat-and-pressure fixing; heat resistant; non-clumpingUS6828072 *Feb 24, 2000Dec 7, 2004Oce Printing Systems GmbhDoes not separate during repeated use; having binder system containing polyester resin as main componentUS6899986Sep 23, 2002May 31, 2005Ricoh Company, Ltd.Passing a toner image- bearing sheet through a nip defined between two rollers including a heater roller to fix the toner image on sheet, wherein toner image is formed from a toner comprising binder resin, and a colorantUS7070898Dec 4, 2003Jul 4, 2006Canon Kabushiki Kaishafavorable fixability, good charge stability, high image density in long-term use, high-resolution image; obtained by polymerizing a monomer and a colorant using an organic peroxide with a 10-hour half-life temperature of 86 degrees C and contains t-butanolUS7094514 *Sep 12, 2003Aug 22, 2006Fuji Xerox Co., Ltd.developing an electrostatic latent image formed on an electrophotographic photoreceptor with a toner for development containing a binder resin and a colorant, the surface of the photoreceptor contains a compound with a double bond, the surface of the toner has metal oxide or metal nitride particleUS7150954Dec 3, 2004Dec 19, 2006Ricoh Company, Ltd.Image forming method and toner for use in the methodUS7187893 *May 6, 2002Mar 6, 2007Seiko Epson CorporationImage transfer unit having an intermediate transfer belt to which a toner image is appliedUS7209690 *Mar 28, 2005Apr 24, 2007Canon Kabushiki KaishaDeveloping apparatusUS7229736Oct 31, 2004Jun 12, 2007Samsung Electronics CompanyLiquid electrophotographic toners comprising amphipathic copolymers having acidic or basic functionality and wax having basic or acidic functionalityUS7306886Oct 31, 2004Dec 11, 2007Samsung Electronics CompanyDry toner comprising waxUS7318987Oct 31, 2004Jan 15, 2008Samsung Electronics CompanyFormed by copolymerizing monomers in the presence of the wax in a liquid carrier having a Kauri-Butanol number less than 30 mL to form an amphipathic copolymer with excellent durability and erasure resistance properties at low fusion temperatures and with little undesired offset.US7354687Oct 31, 2004Apr 8, 2008Samsung Electronics CompanyDry toner blended with waxUS7387860Jun 5, 2007Jun 17, 2008Canon Kabushiki KaishaToner, and image forming methodUS8084178Jun 28, 2006Dec 27, 2011Canon Kabushiki KaishaNon-magnetic tonerUS8346117Aug 30, 2010Jan 1, 2013Ricoh Company, LimitedFixing device and image forming apparatus using sameUS8369749 *Jan 22, 2010Feb 5, 2013Oki Data CorporationDeveloping device and image forming deviceUS8603717Jul 22, 2009Dec 10, 2013Samsung Fine Chemicals Co., Ltd.Toner having multiple inflection points on storage modulus curve with respect to temperature and method of preparing the sameUS20100189468 *Jan 22, 2010Jul 29, 2010Oki Data CorporationDeveloping device and image forming deviceEP1172705A1 *Jul 9, 2001Jan 16, 2002Canon Kabushiki KaishaMagenta tonerEP1296201A1Sep 20, 2002Mar 26, 2003Ricoh Company Ltd.Image forming method and toner thereforEP1505447A2 *Jul 14, 2004Feb 9, 2005Canon Kabushiki KaishaToner, and image forming methodEP2161624A1 *Jun 18, 2008Mar 10, 2010Canon Kabushiki KaishaColor tonerEP2304506A2 *Jul 22, 2009Apr 6, 2011Samsung Fine Chemicals Co., Ltd.Toner having multiple inflection points on storage modulus curve with respect to temperature and method of preparing the same* Cited by examinerClassifications U.S. Classification430/45.54, 430/109.3, 430/107.1, 430/110.3, 430/108.8, 399/302, 430/111.4International ClassificationG03G9/087, G03G9/08Cooperative ClassificationG03G9/08782, G03G9/081, G03G9/0821European ClassificationG03G9/08B6, G03G9/087F3, G03G9/08PLegal EventsDateCodeEventDescriptionMay 18, 2011FPAYFee paymentYear of fee payment: 12May 18, 2007FPAYFee paymentYear of fee payment: 8May 20, 2003FPAYFee paymentYear of fee payment: 4Jan 30, 2001CCCertificate of correctionMay 6, 1998ASAssignmentOwner name: SKI-GLOVE CADDY INC., CANADAFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:HUNT, H. WILLIAM;REEL/FRAME:009155/0940Effective date: 19980421RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google