JP2010152043A - Toner for development of electrostatic charge image, developer for development of electrostatic charge image, image forming apparatus, device for manufacturing toner for development of electrostatic charge image, and method for manufacturing toner for development of electrostatic charge image - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the occurrence of image defects such as a color void when outputting a half-tone image, by suppressing changes due to passage of time inside the charge distribution of toner in a developing unit due to aging, even in an image forming apparatus which does not have trickle mechanism. <P>SOLUTION: A toner for development of an electrostatic charge image includes a binder resin, a colorant, and a release agent and includes colorless particles, wherein the content of the colorless particles having a shape coefficient SF1 of ≤110 is <1% of the total number of particles of the toner. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrostatic charge image developing toner, an electrostatic charge image developing developer, an image forming apparatus, an electrostatic charge image developing toner manufacturing apparatus, and a charge image developing toner manufacturing method.

  A method of visualizing image information through an electrostatic latent image, such as electrophotography, is currently widely used in various fields. In the electrophotographic method, an electrostatic latent image is developed on the surface of an electrophotographic photosensitive member (electrostatic latent image holding body, hereinafter sometimes referred to as “photosensitive member”) through a charging step, an exposure step, and the like. The electrostatic latent image is visualized through a transfer process, a fixing process, and the like by developing with a developer containing toner for use (hereinafter, also simply referred to as “toner”).

  Known toner production methods include a kneading and pulverization method and an emulsion polymerization aggregation method. The former kneading and pulverizing method has a relatively wide particle size distribution of the obtained toner and has an irregular shape, so that performance such as transferability is not always sufficiently maintained.

  In contrast, the emulsion polymerization aggregation method is a production method in which aggregated particles corresponding to the toner particle diameter are formed and then heated to fuse and coalesce the aggregated particles into a toner. By controlling freely from the layer to the surface layer, more precise particle structure control can be realized.

  As the emulsion polymerization aggregation method, for example, methods for preparing latex polymers described in Patent Documents 1 and 2 have been proposed.

JP 2001-247607 A US Pat. No. 5,853,943

  By the way, the toner contains uncolored particles (hereinafter sometimes referred to as “uncolored binder resin particles”) that do not contain a colorant or release agent having the same or similar particle size as the toner particles. In this case, the non-colored binder resin particles mixed in the toner are difficult to be developed, so that they are likely to remain in the developing device. On the other hand, in an image forming apparatus that does not have a trickle mechanism, when image output is performed for a long time, the non-colored binder resin particles mixed in the toner are difficult to be developed, and therefore remain in the developing unit. As a result, the charge distribution of the toner in the developing device changes, and is finally developed in a form containing more of the above-mentioned non-colored binder resin particles as compared with the normal toner composition, for example, outputting a halftone image In this case, the occurrence of image defects such as color loss becomes conspicuous.

  The present invention suppresses the change in the charge distribution of the toner in the developing device over time even by an image forming apparatus that does not have a trickle mechanism by limiting the amount of the non-colored binder resin particles mixed in the toner. The main object is to suppress the occurrence of image defects such as color loss when a halftone image is output.

  As a result of intensive studies to solve the above problems, the present inventors have completed the present invention shown below. The present invention has the following features.

  (1) A toner including a binder resin, a colorant, and a release agent, wherein the toner includes uncolored particles, and the content of uncolored particles having a shape factor SF1 of 110 or less is The toner for developing an electrostatic charge image is less than 1% with respect to the total number of toners.

  (2) The electrostatic charge according to (1), wherein the uncolored particles have a weight average molecular weight of 40,000 or more and 200,000 or less, and the uncolored particles have a volume average particle size of 4 μm or more and 10 μm or less. This is an image developing toner.

  (3) A developer for developing an electrostatic image comprising the toner according to (1) or (2) and a carrier.

  (4) a latent image forming means for forming a latent image on the latent image carrier, a developing means for developing the latent image using an electrostatic charge developing developer, and the developed toner image via an intermediate transfer member. Alternatively, the image forming apparatus includes: a transfer unit that transfers the toner image on the transfer body without being interposed; and a fixing unit that adds and fixes the toner image on the transfer body. An image forming apparatus comprising the developer for electrostatic charge development according to 3).

  (5) A polymerization tank in which a polymerization initiator is added to polymerize the polymerizable monomer to prepare binder resin particles, and at least at the initial stage of the polymerization, a solution containing the polymerizable monomer is removed from the polymerization tank. Addition means for adding from the phase part along the wall surface of the polymerization tank, the obtained resin particle dispersion, a colorant particle dispersion in which at least a colorant is dispersed, and optionally a release agent. Mixing with a release agent particle dispersion, and agglomerating the resin particles, pigment particles, and release agent particles to form aggregated particles, and then heating and stirring tank for coalescing the aggregated particles together, An electrostatic charge developing toner production apparatus comprising:

  (6) The electrostatic charge developing toner production apparatus according to (5), wherein the addition unit is a spray-type addition device or a bowl-like addition device.

  (7) The above (5) or (5), wherein the solution containing the polymerizable monomer is a polymerizable monomer-containing emulsion prepared by emulsifying an oil phase containing the polymerizable monomer and an aqueous phase. The electrostatic charge developing toner production apparatus according to (6).

  (8) A step of emulsifying the oil phase containing the polymerizable monomer for preparing the binder resin and the aqueous phase while stirring to prepare a polymerizable monomer-containing emulsion, and at least polymerization initiation Initially, the polymerizable monomer-containing emulsion is added from the gas phase portion of the polymerization tank along the wall of the polymerization tank, and a polymerization initiator is added to the polymerizable monomer-containing emulsion to add polymerizable monomer weight. And a step of preparing a binder resin particle, a binder resin particle dispersion in which the binder resin particle is dispersed, a colorant dispersion in which a colorant is dispersed, and a release agent dispersion in which a release agent is dispersed. An agglomeration step of mixing and aggregating the particles with toner particle size containing binder resin particles and a colorant; and heating the resulting aggregate to a temperature above the glass transition point of the binder resin particles to fuse the toner particles And a fusing step to form a toner for developing an electrostatic charge image.

  According to the first aspect of the present invention, even when used in an image forming apparatus that does not have a trickle mechanism, a change in the toner charge distribution in the developing device over time is suppressed, and a halftone image is output. In this case, image defects such as color loss are suppressed.

  According to the second aspect of the present invention, the occurrence of image defects such as color loss when a halftone image is output is further suppressed.

  According to the third aspect of the present invention, even when used in an image forming apparatus that does not have a trickle mechanism, a change in the toner charge distribution in the developing device over time is suppressed, and a halftone image is output. In this case, image defects such as color loss are suppressed.

  According to the invention described in claim 4 of the present application, even when image formation is performed using an image forming apparatus that does not have a trickle mechanism, a change in toner charge distribution in the developing device over time is suppressed, Occurrence of image defects such as color loss when a halftone image is output is suppressed.

  According to the invention of claim 5 of the present application, the polymerization monomer starts polymerization from the wall surface of the polymerization tank at the start of polymerization, and the polymer adheres to the wall surface of the polymerization tank. The heat transfer effect to the polymerization tank can be suppressed. As a result, the cooling to suppress the temperature rise at the start of polymerization suppresses the rapid deactivation of the initiator and the radical of the polymerizable monomer near the side surface of the polymerization tank, and prevents the polymerization of the polymer. The On the other hand, even if the polymer adheres to the polymerization tank at the start of polymerization and the cooling is promoted compared to the conventional case, the temperature in the polymerization tank is controlled by the polymerization set temperature, so the radicals of the initiator and polymerizable monomer The deactivation is not rapidly deactivated, and the polymerizable monomer is polymerized at a preset polymerization degree, so that a large binder resin particle having a high polymerization degree (ie, uncolored binder resin particles) Generation is suppressed.

  According to the sixth aspect of the present invention, at the start of polymerization, a solution containing a polymerizable monomer is selectively supplied to the wall surface of the polymerization tank.

  According to the seventh aspect of the present invention, binder resin particles having a narrow particle size distribution are produced using a polymerizable monomer-containing emulsion.

  According to the invention described in claim 8 of the present application, the polymerization monomer starts polymerization from the wall surface of the polymerization tank at the start of polymerization, and the polymer adheres to the wall surface of the polymerization tank. The heat transfer effect to the polymerization tank can be suppressed. As a result, the cooling to suppress the temperature rise at the start of polymerization suppresses the rapid deactivation of the initiator and the radical of the polymerizable monomer near the side surface of the polymerization tank, and prevents the polymerization of the polymer. The On the other hand, even if the polymer adheres to the polymerization tank at the start of polymerization and the cooling is promoted compared to the conventional case, the temperature in the polymerization tank is controlled by the polymerization set temperature, so the radicals of the initiator and polymerizable monomer The deactivation is not rapidly deactivated, and the polymerizable monomer is polymerized at a preset polymerization degree, so that a large binder resin particle having a high polymerization degree (ie, uncolored binder resin particles) Generation is suppressed.

  An electrostatic charge image developing toner, an electrostatic charge image developing developer, an image forming apparatus, an electrostatic charge image developing toner manufacturing apparatus, and a charge image developing toner manufacturing method according to an embodiment of the present invention will be described below. .

[Toner for electrostatic charge development and method for producing the same]
The electrostatic charge developing toner (hereinafter also referred to as “toner”) according to the present embodiment is a toner including a binder resin, a colorant, and a release agent, and the toner includes non-colored particles and has a shape. The content of uncolored particles having a coefficient SF1 of 110 or less is less than 1% with respect to the total number of the toners.

  When the resin particles in the emulsion polymerization aggregation method to be described later are prepared by emulsion polymerization, in order to control the heat generation during the polymerization and keep the temperature in the polymerization tank at a preset temperature, the cooling particles provided on the outer wall of the polymerization tank The jacket cools from the wall of the polymerization tank. As a result, the temperature of the inner wall of the polymerization tank is lower than the solution temperature inside the polymerization tank, and the radicals of the initiator and the polymerizable monomer are more easily deactivated in the vicinity of the inner wall of the polymerization tank than in the polymerization tank. Since the number is relatively small, polymerization of the polymer is promoted near the inner wall surface of the polymerization tank as compared with the inside of the polymerization tank, and uncolored binder resin particles are easily formed. Therefore, when the polymerization is performed for a long time with the inner wall surface of the polymerization tank exposed, polymerization of the polymer is continuously promoted near the inner wall surface of the polymerization tank, and uncolored binder resin particles are formed. . The non-colored binder resin particles are not only difficult to remove from the resin particle dispersion, but also remain at the time of toner preparation by the emulsion polymerization aggregation method, so that they are mixed in the toner as a result. By increasing the ratio of the non-colored binder resin particles to the toner, a problem such as color loss is likely to occur in an image that is likely to be affected by the fixing of one toner such as a halftone.

  Therefore, in this embodiment, the conventional method for adding a polymerizable monomer to a polymerization tank is improved, the polymerization starts from the polymerization tank wall surface, and the polymer adheres to the polymerization tank wall surface. By suppressing the heat transfer effect from the start of polymerization to the polymerization tank during polymerization and cooling to suppress the temperature rise at the start of polymerization, the initiator and radicals of the polymerizable monomer near the side of the polymerization tank The rapid deactivation of the polymer is suppressed, and the polymerization of the polymer is prevented. On the other hand, even if the polymer adheres to the polymerization tank at the start of polymerization and the cooling is promoted compared to the conventional case, the temperature in the polymerization tank is controlled by the polymerization set temperature, so the radicals of the initiator and polymerizable monomer The deactivation is not rapidly deactivated, and the polymerizable monomer is polymerized at a preset polymerization degree, so that a large binder resin particle having a high polymerization degree (ie, uncolored binder resin particles) Generation is suppressed. In addition, after the polymerization starts, the polymer adheres thinner and more uniformly than before, and polymerization of the polymer is suppressed. Therefore, the amount of polymer attached to the inner wall of the polymerization tank is reduced, and the amount of polymer on the inner wall of the polymerization tank is reduced. As a result, the productivity of the binder resin particle dispersion and the toner is improved, and the work load and safety are also improved.

  Accordingly, the mixing ratio of the above-mentioned non-colored binder resin particles that are difficult to be developed in the toner is lower than that of the conventional toner, and even in the image forming apparatus that does not have the trickle mechanism, The amount of the non-colored binder resin particles remaining in the toner is reduced, and as a result, the change in the charge distribution of the toner in the developing device is suppressed. Accordingly, even when the toner containing the non-colored binder resin particles after the image output for a long time is developed, the occurrence of image defects such as color loss is suppressed when the halftone image is output.

  The number of the above-mentioned non-colored binder resin particles is less than 1% with respect to the total number of toners. Thus, the mixing ratio of the above-mentioned non-colored binder resin particles that are difficult to be developed in the toner is compared with the conventional toner. Even if the image forming apparatus does not have a trickle mechanism, the change in the toner charge distribution in the developing unit is suppressed, and the occurrence of image defects such as color loss when a halftone image is output is suppressed. To do. More preferably, non-colored binder resin particles having a weight average molecular weight of 40,000 or more and 200,000 or less, a particle size of 4 μm or more and 10 μm or less, and a shape factor SF1 of 110 or less (“uncolored particles”). Content) is less than 1% with respect to the total number of toners. The number of the above-mentioned non-colored binder resin particles present in the toner is preferably as small as possible, and most preferably 0, but the temperature in the polymerization tank is controlled using a cooling jacket. Since it is rare that the temperature in the vicinity of the inner wall of the polymerization tank and the inside of the polymerization tank are equal, zero is not very realistic.

  The weight average molecular weight of the non-colored binder resin particles is 40,000 or more and 200,000 or less, and the particle size is 4 μm or more and 10 μm or less. Having a particle size of less than 40,000 and a particle size of less than 4 μm is more easily developed than uncolored binder resin particles having a size larger than that, and therefore is an image forming apparatus having no trickle mechanism. However, there is little change in the ratio of the non-colored binder resin particles to the toner in the developing device over time, and the problem of color loss does not easily occur. On the other hand, the toner having a weight average molecular weight exceeding 200,000 and a particle diameter exceeding 10 μm is separated by furnace after the production of the binder resin particles, so that its inclusion in the developing toner is suppressed.

  Further, the shape factor SF1 of the non-colored binder resin particles is preferably 110 or less. An image such as a halftone image is required to have uniformity during development of toner on the photosensitive member during development and transfer from the photosensitive member to the transfer target. Since the non-colored binder resin particles have different charging characteristics from the toner particles, the image tends to be disturbed due to electric repulsion with respect to other toners in each step of development and transfer, and the uncolored SF1 exceeds 110. This is presumably because the binder resin particles are more likely to cause variations in the charging characteristics, and as a result, the image tends to be further deteriorated.

  A release agent may be added to the toner of the present embodiment. Examples of release agents used include low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene, silicones that exhibit a softening point upon heating, fatty acids such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide. Amides, plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil, animal waxes such as beeswax, montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Examples thereof include mineral-based and petroleum-based waxes such as Fischer-Tropsch wax, ester-based waxes such as fatty acid esters, montanic acid esters, and carboxylic acid esters, and modified products thereof. These release agents may be used alone or in combination of two or more.

  A preferred release agent used in the toner of the present embodiment is a release agent having a low compatibility with the binder resin, for example, a release agent having a low polarity such as polyethylene or polyolefin. The half-tone image containing the toner is preferable in terms of good releasability, and the weight average molecular weight is 500 to 5000, and the melting temperature is 60 ° C. to 100 ° C. It is preferable from the viewpoint of difficulty. As described above, since the release agent needs to enter between the fixing member and the image in a short time from the inside of the toner, the release agent is preferably a release agent of the type of release agent exemplified above.

  Further, various materials constituting the toner of the present embodiment will be described in detail.

  As the binder resin used, styrenes such as styrene and chlorostyrene, monoolefins such as ethylene, propylene, butylene and isoprene, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate and vinyl butyrate, Α-methylene aliphatic monocarboxylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate Homopolymers and copolymers such as vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl butyl ether, vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropenyl ketone. In particular, typical binder resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, and styrene-anhydrous. Mention may be made of maleic acid copolymers, polyethylene, polypropylene and the like. Further examples include polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin wax and the like.

  In addition, toner colorants include magnetic powders such as magnetite and ferrite, carbon black, aniline blue, caryl blue, chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, and malachite green oxa. Rate, lamp black, rose bengal, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 57: 1, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 17, C.I. I. Pigment blue 15: 1, C.I. I. Pigment Blue 15: 3 can be exemplified as a representative one.

  In addition, various components such as an internal additive, a charge control agent, inorganic powder (inorganic particles), and organic particles can be added as necessary. Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel and manganese, alloys, and magnetic materials such as compounds containing these metals. Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments. The inorganic powder is added mainly for the purpose of adjusting the viscoelasticity of the toner. For example, alumina, titania, calcium carbonate, magnesium carbonate, calcium phosphate, cerium oxide, etc. All inorganic particles used as an external additive are included. Moreover, as a flocculant, besides a surfactant, an inorganic salt or a divalent or higher metal salt can be suitably used. In particular, when a metal salt is used, it is preferable in characteristics such as cohesion control and toner chargeability.

  The toner has a volume average particle diameter of 3 to 10 μm, preferably 3 to 9 μm, and more preferably 3 to 8 μm. The number average particle diameter of the toner of the present embodiment is preferably 3 to 10 μm, and more preferably 2 to 8 μm. If the particle size is too small, not only the productivity becomes unstable, but the chargeability becomes insufficient and the developability may be lowered, and if it is too large, the resolution of the image is lowered.

  The method for producing a toner in the present embodiment includes a step of emulsifying an oil phase containing a polymerizable monomer for preparing a binder resin and an aqueous phase while stirring to obtain a polymerizable monomer-containing emulsion. Adding the polymerizable monomer-containing emulsion at the initial stage of polymerization and along the wall of the polymerization tank from the gas phase part of the polymerization tank, and preparing a polymerization initiator in the polymerizable monomer-containing emulsion To prepare a binder resin particle by polymerizing a polymerizable monomer and dispersing a binder resin particle dispersion in which the binder resin particles are dispersed, a colorant dispersion in which a colorant is dispersed, and a release agent And aggregating step of aggregating the obtained release agent dispersion liquid into particles having a toner particle diameter containing binder resin particles and a colorant, and the obtained aggregate is equal to or higher than the glass transition point of the binder resin particles (for example, A fusion process in which toner particles are formed by heating and fusing to a temperature of 1.6 times Tg or higher) It will be preferable to include.

  FIG. 1 shows an example of the configuration of a toner manufacturing apparatus used in the toner manufacturing method of the present embodiment. As shown in FIG. 1, the toner manufacturing apparatus according to the present embodiment includes an emulsification tank 100 that emulsifies one or more polymer monomers, water, and, if necessary, a surfactant, and an emulsification tank 100. An initiator is added to the prepared polymer monomer-containing emulsion to carry out emulsion polymerization, and a polymerization tank 120 for preparing binder resin particles, the obtained resin particle dispersion, and at least a colorant are dispersed. The colorant particle dispersion obtained by mixing with a release agent particle dispersion obtained by optionally dispersing a release agent, and the resin particles, the pigment particles, and the release agent particles are aggregated to form aggregated particles. And a stirring tank 140 for heating and coalescing the aggregated particles.

  The emulsification tank 100 includes a drive source 11 such as a motor for driving the stirring means 12 provided with a stirring blade, a temperature sensor 13 for measuring the temperature of the polymerizable monomer-containing emulsion 10 in the emulsification tank 100, and a connection. An oil phase supply line 14 for supplying an oil phase containing a polymerizable monomer for preparing a landing resin, and an aqueous phase supply line 15 for supplying an aqueous phase containing a surfactant as required. And have. Further, the oil phase supply line 14 is provided with an automatic open / close valve 16, and the water phase supply line 15 is provided with an automatic open / close valve 18.

  The polymerization tank 120 includes a jacket 30 provided on the outer wall of the polymerization tank 120, a drive source 21 such as a motor for driving the stirring means 22 provided with the stirring blades, and the temperature of the polymerization solution 20 in the polymerization tank 120. A temperature sensor 23 for measuring the polymerization amount, a polymerization initiator storage tank 40 in which a polymerization initiator is stored, and a polymerizable monomer-containing emulsion 10 for supplying the polymerizable monomer-containing emulsion 10 from the emulsion tank 100 An emulsion supply line 25 and an initiator supply line 42 for supplying an initiator from the polymerization initiator storage tank 40 are provided. The polymerizable monomer-containing emulsion supply line 25 is provided with an adding means 24 for adding the polymerizable monomer-containing emulsion 10 from the gas phase portion of the polymerization tank 120 along the wall surface of the polymerization tank. Furthermore, an automatic opening / closing valve 26 is provided in the polymerizable monomer-containing emulsion supply line 25, and an automatic opening / closing valve 28 is provided in the initiator supply line 42. A cooling water supply line 34 provided with an automatic opening / closing valve 36 and a cooling water discharge line 35 provided with an automatic opening / closing valve 38 are connected to the jacket 30 for cooling.

  The agitation tank 140 is provided with a jacket 60 provided on the outer wall of the agitation tank 140 and a drive source 51 such as a motor for driving the agitation means provided with the agitation blades. Binder resin particle dispersion supply line 55 for supplying resin particle dispersion liquid, colorant dispersion liquid supply line 54 for supplying colorant dispersion liquid in which a colorant is dispersed, and release agent dispersion liquid in which a release agent is dispersed And a release agent dispersion supply line 57 for supplying the liquid. The binder resin particle dispersion supply line 55 is provided with an automatic open / close valve 56, the colorant dispersion liquid supply line 54 is provided with an automatic open / close valve 52, and the release agent dispersion liquid supply line 57 is automatically opened / closed. A valve 58 is provided. Further, a steam or cooling water supply line 64 provided with an automatic opening / closing valve 66 and a steam or cooling water discharge line 65 provided with an automatic opening / closing valve 68 are connected to the jacket 60 for heating or cooling. Yes.

  Therefore, the driving source 11 is driven to drive the agitation means 22, the automatic opening / closing valves 16 and 18 are opened, and the polymerizable monomer is supplied from the oil phase supply line 14 to the emulsification tank 100 with a predetermined supply amount. The aqueous phase containing the surfactant is supplied from the aqueous phase supply line 15 as necessary, and the polymerizable monomer-containing emulsion 10 is prepared.

  Next, the drive source 22 is driven to drive the stirring means 22 to open the automatic opening / closing valves 26 and 28, and the initiator or the initiator solution is transferred from the initiator storage tank 40 through the initiator supply line 42 to the polymerization tank 120. Simultaneously with the supply, the polymerizable monomer-containing emulsion 10 supplied from the polymerizable monomer-containing emulsion supply line 25 is added along the inner wall surface of the polymerization tank 120 using the adding means 24. On the other hand, the automatic open / close valve 36 is opened to the jacket 30, and cooling water is supplied via the cooling water supply line 34. The automatic open / close valve 38 is opened and the cooled water is discharged via the cooling water discharge line 35. . The supply amount and discharge amount of the cooling water are controlled according to the output of the temperature sensor 23.

  Next, the drive source 51 is driven to drive the stirring means, and the automatic opening / closing valve 56 is opened, and the obtained binder resin particle dispersion is transferred to the stirring tank 140 via the binder resin particle dispersion supply line 55. On the other hand, the automatic open / close valves 52 and 58 are opened, the colorant dispersion is supplied to the stirring tank 140 via the colorant dispersion supply line 54, and the mold release is performed via the release agent dispersion supply line 57. The agent dispersion is supplied to the stirring tank 140. Automatic opening / closing valves 66 and 68 are opened in the jacket 60, and steam or cooling water is supplied to the steam or cooling water supply line 64 and the steam or cooling water discharge line 65, respectively, according to the aggregation process and the fusion process. The supply amount and discharge amount of steam or cooling water are controlled according to the output of the temperature sensor 53.

  Further, as described above, the polymerizable monomer-containing emulsion 10 is added from the gas phase portion of the polymerization tank 120 along the wall surface of the polymerization tank 120 to the polymerization tank 120 in the toner manufacturing apparatus of the present embodiment. An adding means 24 is provided. The configuration of the adding means 24 will be described below with reference to FIGS.

  First, an example of a method for adding a polymerizable monomer-containing emulsion in a conventional polymerization tank will be described with reference to FIG. As shown in FIG. 5, the conventional addition means of the polymerization tank 120d is a nozzle type addition device 24d, and the polymerizable monomer-containing emulsion 10 is added from one place of the polymerization tank 120d. In such a case, in order to control the heat generation during polymerization and keep the temperature in the polymerization tank 120d at a preset temperature, cooling is performed from the wall surface of the polymerization tank 120d by a cooling jacket provided on the outer wall of the polymerization tank 120d. . As a result, the temperature of the inner wall surface of the polymerization tank 120d is lower than the solution temperature inside the polymerization tank 120d, and the radicals of the initiator and polymerizable monomer are lost in the vicinity of the inner wall surface of the polymerization tank 120d as compared with the inside of the polymerization tank. Since it is easy to activate and the number of radicals is relatively small, polymerization of the polymer is promoted near the inner wall surface of the polymerization tank 120d as compared to the inside of the polymerization tank 120d, and uncolored binder resin particles are easily formed. Become. Further, when the polymerization is performed for a long time with the inner wall surface of the polymerization tank 120d exposed, the polymerization of the polymer is continuously promoted in the vicinity of the inner wall surface of the polymerization tank, and the toner particles having a high degree of polymerization are coarse. Binder resin particles (that is, non-colored binder resin particles) are formed.

  On the other hand, the addition means of the polymerization tank 120a as an example of the present embodiment shown in FIG. 2 is a spray-type addition device 24, and the addition port of the polymerizable monomer-containing emulsion 10 is 1 in the spray-type addition device 24. The place is formed. However, the present invention is not limited to this, and a plurality of addition ports may be formed. Further, the spray-type addition device 24 is configured to be rotatable so that the polymerizable monomer-containing emulsion 10 can be added in different directions from the addition port of the spray-type addition device 24. Furthermore, the addition rate of the polymerizable monomer-containing emulsion 10 from the addition port of the spray-type addition device 24 is relatively high when the polymerizable monomer-containing emulsion 10 is added to the relatively close polymerization vessel wall surface. It is controlled to the extent that there is no big bounce.

  FIG. 3 shows a polymerization tank 120b of another example of the present embodiment, and the addition means of the polymerization tank 120b includes two spray-type addition devices 24a and 24b, and the spray-type addition device shown in FIG. In 24a and 24b, one addition port for the polymerizable monomer-containing emulsion 10 is formed, but the present invention is not limited to this, and a plurality of addition ports may be formed. Further, the spray-type addition devices 24a and 24b are configured to be rotatable so that the polymerizable monomer-containing emulsion 10 can be added in different directions from the addition ports of the spray-type addition devices 24a and 24b. Also, the addition rate of the polymerizable monomer-containing emulsion 10 from the addition ports of the spray-type addition devices 24a and 24b is such that the polymerizable monomer-containing emulsion 10 is added to the relatively close polymerization vessel wall surface. It is controlled to the extent that there is no relatively large bounce. By providing the two spray-type addition devices 24a and 24b shown in FIG. 3, the polymerizable monomer-containing emulsion 10 can be polymerized in a short time from the start of polymerization compared to the spray-type addition device 24 shown in FIG. It is added toward the inner wall surface of 120b. As a result, a more uniform polymer adheres to the inner wall surface of the polymerization tank 120b at an early stage, a relatively thin polymer film is formed, heat transfer from the jacket 30 is suppressed, and the vicinity of the inner wall surface of the polymerization tank 120b. And the temperature difference between the inside and the inside becomes smaller than before, and generation of coarse binder resin particles (that is, non-colored binder resin particles) having a high degree of polymerization and large toner particles is suppressed. In FIG. 3, two spray-type addition devices 24a and 24b are shown. However, the present invention is not limited to this, and a plurality of spray-type addition devices 24a and 24b may be provided as long as the space in the gas phase portion of the polymerization tank 120b allows.

  FIG. 4 shows a polymerization tank 120c of another example of the present embodiment, and the addition means of the polymerization tank 120c is a dish-like portion and a dish that are fixed to the stirring means and receive the polymerizable monomer-containing emulsion 10. It is a guide type addition apparatus 24c which consists of a bowl-shaped part extended | stretched from the shape part. Therefore, the polymerizable monomer-containing emulsion 10 passes along the inner wall surface of the polymerization tank 120c from the dish-like portion of the guide-type addition device 24c shown in FIG. ) Is added. Here, at least two bowl-shaped portions of the guide-type adding device 24c are provided, and are provided to extend to the dish-shaped portion while maintaining an equal angle to each other. Compared with the conventional nozzle type addition device 24d shown in FIG. 5, the guide type addition device 24c shown in FIG. 4 directs the polymerizable monomer-containing emulsion 10 toward the inner wall surface of the polymerization tank 120c in a short time from the start of polymerization. Added. As a result, a more uniform polymer adheres to the inner wall surface of the polymerization tank 120c at an early stage, a relatively thin polymer film is formed, heat transfer from the jacket 30 is suppressed, and the vicinity of the inner wall surface of the polymerization tank 120c. And the temperature difference between the inside and the inside becomes smaller than before, and generation of coarse binder resin particles (that is, non-colored binder resin particles) having a high degree of polymerization and large toner particles is suppressed.

[Developer for electrostatic charge development]
The toner obtained by the method for producing an electrostatic charge developing toner of the present invention described above is used as an electrostatic charge developer. The developer is not particularly limited except that it contains the electrostatic charge developing toner, and can take an appropriate component composition according to the purpose. When the electrostatic charge developing toner is used alone, it is prepared as a one-component electrostatic charge developer, and when used in combination with a carrier, it is prepared as a two-component electrostatic charge developer.

  The carrier is not particularly limited, and examples thereof include known carriers. For example, known carriers such as resin-coated carriers described in JP-A-62-39879, JP-A-56-11461, etc. Can be used.

  Specific examples of the carrier include the following resin-coated carriers. That is, examples of the core particle of the carrier include normal iron powder, ferrite, and magnetite molding, and the average particle diameter is about 30 to 200 μm. Examples of the coating resin for the core particles include styrenes such as styrene, parachlorostyrene, and α-methylstyrene, methyl acrylate, ethyl acrylate, n-propyl acrylate, lauryl acrylate, and 2-ethylhexyl acrylate. , Α-methylene fatty acid monocarboxylic acids such as methyl methacrylate, n-propyl methacrylate, lauryl methacrylate and 2-ethylhexyl methacrylate, nitrogen-containing acrylics such as dimethylaminoethyl methacrylate, vinyl nitriles such as acrylonitrile and methacrylonitrile Vinyl pyridines such as 2-vinyl pyridine and 4-vinyl pyridine, vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether, vinyl vinyls such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone Luketones, polyolefins such as ethylene and propylene, silicones such as methylsilicone and methylphenylsilicone, and vinylidene fluoride. Particularly preferred are copolymers of vinyl-containing fluorine-containing monomers such as tetrafluoroethylene hexafluoroethylene, polyesters containing bisphenol, glycol, etc., epoxy resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, etc. Is a resin obtained by polymerizing a polymerizable monomer having an aromatic ring. The reason for this is that the resin obtained by polymerizing the polymerizable monomer having an aromatic ring tends to retain static electricity in the aromatic ring portion when charged with the toner, and therefore the ratio of the non-colored binder resin particles. This is because it is considered that the generation of an excessive charge amount of the non-colored binder resin particles can be controlled even when the amount of toner increases in the developer. More preferably, it is a resin obtained by polymerizing a polymerizable monomer containing, as a polymerizable monomer, styrene in which the aromatic ring portion is easily in direct contact with the toner. The reason is preferably a resin obtained by polymerizing the polymerizable monomer having an aromatic ring. These resins may be used alone or in combination of two or more. As a quantity of this coating resin, it is about 0.1-10 parts with respect to a carrier, and 0.5-3.0 mass parts is preferable. In the production of the carrier, a heating kneader, a heating Henschel mixer, a UM mixer, or the like can be used. Depending on the amount of the coating resin, a heating fluidized rolling bed, a heating kiln, or the like can be used. it can.

  The mixing ratio between the electrostatic charge developing toner and the carrier in the electrostatic charge developer is not particularly limited and may be appropriately selected depending on the purpose.

[Image forming apparatus]
Next, the image forming apparatus of the present embodiment will be described.

  FIG. 6 is a schematic diagram illustrating a configuration example of an image forming apparatus for forming an image by the image forming method of the present embodiment. In the illustrated image forming apparatus 200, four electrophotographic photosensitive members 401 a to 401 d are disposed in parallel in the housing 400 along the intermediate transfer belt 409. The electrophotographic photoreceptors 401a to 401d form, for example, images in which the electrophotographic photoreceptor 401a is yellow, the electrophotographic photoreceptor 401b is magenta, the electrophotographic photoreceptor 401c is cyan, and the electrophotographic photoreceptor 401d is black. Is possible.

  Each of the electrophotographic photosensitive members 401a to 401d can be rotated in a predetermined direction (counterclockwise on the paper surface), and the charging rolls 402a to 402d, the developing devices 404a to 404d, and the primary transfer roll 410a along the rotation direction. To 410d and cleaning blades 415a to 415d are arranged. Each of the developing devices 404a to 404d can be supplied with toner of four colors of black, yellow, magenta and cyan accommodated in the toner cartridges 405a to 405d, and the primary transfer rolls 410a to 410d are respectively intermediate transfer belts. 409 is in contact with the electrophotographic photoreceptors 401a to 401d.

  Further, an exposure device 403 is disposed at a predetermined position in the housing 400, and it becomes possible to irradiate the surfaces of the charged electrophotographic photoreceptors 401a to 401d with a light beam emitted from the exposure device 403. ing. Accordingly, charging, exposure, development, primary transfer, and cleaning are sequentially performed in the rotation process of the electrophotographic photosensitive members 401a to 401d, and the toner images of the respective colors are transferred onto the intermediate transfer belt 409 in an overlapping manner.

  Here, the charging rolls 402a to 402d contact the surface of the electrophotographic photoreceptors 401a to 401d with a conductive member (charging roll), and apply a voltage uniformly to the photoreceptor to charge the photoreceptor surface to a predetermined potential. (Charging process). In addition to the charging roll shown in this embodiment, charging by a contact charging method may be performed using a charging brush, a charging film, a charging tube, or the like. Moreover, you may charge by the non-contact system using a corotron or a scorotron.

  As the exposure apparatus 403, an optical system apparatus or the like that can expose a light source such as a semiconductor laser, an LED (light emitting diode), a liquid crystal shutter, or the like on the surface of the electrophotographic photoreceptors 401a to 401d can be used. Among these, when an exposure apparatus capable of exposing non-interference light is used, interference fringes between the electroconductive substrates of the electrophotographic photoreceptors 401a to 401d and the photosensitive layer can be prevented.

  As the developing devices 404a to 404d, a general developing device that develops the two-component electrostatic image developer in contact or non-contact with the developer can be used (developing step). Such a developing device is not particularly limited as long as a two-component electrostatic image developing developer is used, and a known one can be appropriately selected according to the purpose. In the primary transfer process, a primary transfer bias having a polarity opposite to that of the toner carried on the image carrier is applied to the primary transfer rolls 410a to 410d, so that each color toner is transferred from the image carrier to the intermediate transfer belt 409. The primary transfer is performed sequentially.

  The cleaning blades 415a to 415d are for removing residual toner adhering to the surface of the electrophotographic photosensitive member after the transfer process, and the electrophotographic photosensitive member cleaned by this cleaning process is repeatedly used in the above-described image forming process. Is done. Examples of the material for the cleaning blade include urethane rubber, neoprene rubber, and silicone rubber.

  The intermediate transfer belt 409 is supported with a predetermined tension by a drive roll 406, a backup roll 408, and a tension roll 407, and can rotate without causing deflection due to the rotation of these rolls. Further, the secondary transfer roll 413 is disposed so as to contact the backup roll 408 via the intermediate transfer belt 409.

  By applying a secondary transfer bias having a reverse polarity to the toner on the intermediate transfer body to the secondary transfer roll 413, the toner is secondarily transferred from the intermediate transfer belt to the recording medium. The intermediate transfer belt 409 that has passed between the backup roll 408 and the secondary transfer roll 413 is cleaned by, for example, a cleaning blade 416 disposed near the drive roll 406 or a static eliminator (not shown). It is repeatedly used for the next image forming process. A tray (transfer medium tray) 411 is provided at a predetermined position in the housing 400, and the transfer medium 500 such as paper in the tray 411 is transferred to the intermediate transfer belt 409 and the secondary transfer roll by the transfer roll 412. Then, the paper is sequentially transferred between the two fixing rolls 414 that are in contact with each other and the two fixing rolls 414 that are in contact with each other.

<Image forming method>
The image forming method in the present embodiment includes at least the step of charging the image carrier, the step of forming a latent image on the image carrier, and the electrophotographic developer described above with the latent image on the latent image carrier. A step of developing the toner image, a primary transfer step of transferring the developed toner image onto the intermediate transfer member, a secondary transfer step of transferring the toner image transferred to the intermediate transfer member to a recording medium, Fixing the toner image by heat and pressure. The developer is a developer containing at least the electrostatic image developing toner of the present invention. The developer may be either a one-component system or a two-component system.

  As each of the above steps, a known step in the image forming method can be used.

  As the latent image holding member, for example, an electrophotographic photosensitive member and a dielectric recording member can be used. In the case of an electrophotographic photosensitive member, the surface of the electrophotographic photosensitive member is uniformly charged by a corotron charger, a contact charger or the like and then exposed to form an electrostatic latent image (latent image forming step). Next, the toner particles are adhered to the electrostatic latent image in contact with or in proximity to a developing roll having a developer layer formed on the surface, thereby forming a toner image on the electrophotographic photosensitive member (developing step). The formed toner image is transferred onto the surface of a transfer medium such as paper using a corotron charger or the like (transfer process). Further, if necessary, the toner image transferred to the surface of the transfer material is heat-fixed by a fixing device to form a final toner image.

  In the heat fixing by the fixing device, a release agent is supplied to a fixing member in a normal fixing device in order to prevent an offset or the like, but the fixing device of the image forming apparatus in the present embodiment In this case, it is not necessary to supply a release agent, and fixing is performed without oil.

  The method for supplying the release agent to the surface of the roller or belt, which is a fixing member used for heat fixing, is not particularly limited. For example, a pad method using a pad impregnated with a liquid release agent, a web method, a roller method. Non-contact shower method (spray method) and the like, and the web method and the roller method are particularly preferable. These methods are advantageous in that the release agent can be supplied uniformly and it is easy to control the supply amount. In order to supply the release agent uniformly to the entire fixing member by the shower method, it is necessary to use a separate blade or the like.

  Examples of the transfer target (recording material) to which the toner image is transferred include plain paper, OHP sheet, and the like used in electrophotographic copying machines and printers.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these.

  First, in this example, each measurement was performed as follows.

-Particle size and particle size distribution measurement method-
The particle size (also referred to as “particle size”) and particle size distribution measurement (also referred to as “particle size distribution measurement”) will be described.

  When the particle diameter to be measured was 2 μm or more, Coulter Multisizer-II type (manufactured by Beckman-Coulter) was used as the measuring apparatus, and ISOTON-II (manufactured by Beckman-Coulter) was used as the electrolyte.

  As a measurement method, 0.5 to 50 mg of a measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate, as a dispersant. This was added to 100 ml of the electrolytic solution.

  The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute, and the particle size distribution of particles of 2 to 60 μm is measured using the Coulter counter TA-II with an aperture diameter of 100 μm. Volume average distribution and number average distribution were determined. The number of particles to be measured was 50,000.

  The particle size distribution of the toner was determined by the following method. For the particle size range (channel) obtained by dividing the measured particle size distribution, draw the volume cumulative distribution from the smaller particle size, define the cumulative volume particle size to be 16% cumulative as D16v, and the cumulative volume to be 50% cumulative The particle size is defined as D50v. Furthermore, the cumulative volume particle diameter that is 84% cumulative is defined as D84v.

The volume average particle size in the present invention is D50v, and the volume average particle size index GSDv is calculated by the following equation.
Formula: GSDv = {(D84v) / (D16v)} ^0.5

  Moreover, when the particle diameter to measure was less than 2 micrometers, it measured using the laser diffraction type particle size distribution measuring apparatus (LA-700: made by Horiba, Ltd.). As a measurement method, a sample in a dispersion is adjusted to have a solid content of about 2 g, and ion exchange water is added thereto to make about 40 ml. This is put into the cell until an appropriate concentration is reached, waits for about 2 minutes, and is measured when the concentration in the cell becomes almost stable. The obtained volume average particle diameter for each channel was accumulated from the smaller volume average particle diameter, and the volume average particle diameter was determined to be 50%.

  When measuring powders such as external additives, 2 g of a measurement sample is added to 50 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate, and 2 with an ultrasonic disperser (1,000 Hz). A sample was prepared by dispersing for a minute, and the measurement was performed in the same manner as the above dispersion.

-Method of measuring toner shape factor SF1-
The shape factor SF1 of the toner is a shape factor SF indicating the degree of unevenness on the toner particle surface, and was calculated by the following equation.
Formula: SF1 = (ML ² / A) × (π / 4) × 100
In the formula, ML represents the maximum length of toner particles, and A represents the projected area of the particles. For the measurement of the shape factor SF1, first, an optical microscope image of toner dispersed on a slide glass was taken into an image analysis device through a video camera, and SF was calculated for 50 or more toners to obtain an average value.

-Measurement method of molecular weight and molecular weight distribution of toner and resin particles-
The molecular weight distribution is performed under the following conditions. GPC uses “HLC-8120GPC, SC-8020 (manufactured by Tosoh Corp.)”, and two columns use “TSKgel, SuperHM-H (Tosoh Corp., 6.0 mm ID × 15 cm)”. , THF (tetrahydrofuran) was used as an eluent. As experimental conditions, an experiment was performed using a sample concentration of 0.5%, a flow rate of 0.6 ml / min, a sample injection amount of 10 μl, a measurement temperature of 40 ° C., and an IR detector. The calibration curve is “polystylen standard sample TSK standard” manufactured by Tosoh Corporation: “A-500”, “F-1”, “F-10”, “F-80”, “F-380”, “A-2500”. ”,“ F-4 ”,“ F-40 ”,“ F-128 ”, and“ F-700 ”.

-Number of uncolored binder resin particles-
Using an optical microscope ("LUZEX" manufactured by Nireco), an observation image of the entire toner is taken, and about 5000 toners arbitrarily extracted are obtained by image analysis. Then, the particles were observed at a magnification of 800 to obtain particles satisfying the conditions that the particles were white and that the shape factor SF1 of the toner was 110 or less.

  Also, the shape factor SF1 of the particles could be obtained by this method.

  Although the more specific comparative example and Example in this invention are demonstrated below, the following Examples do not limit the content of this invention at all. In the following description, “part” means “part by mass” unless otherwise specified.

[Evaluation of toner production examples and developers]
<Production of Toners 1a to 1d>
-Production of resin particle dispersion (1)-
370 parts by mass of ion-exchanged water and 0.3 part by mass of a surfactant were added to the polymerization tank, and the temperature was raised to 75 ° C. while stirring and mixing. On the other hand, the following components were charged into an emulsification tank and mixed by stirring to prepare an emulsion.

Ion-exchanged water 170 parts by mass Nonionic surfactant (Nonipol 400: manufactured by Sanyo Chemical Co., Ltd.) 2 parts by mass and anionic surfactant (Neogen SC: manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 3 parts by mass styrene 300 4 parts by mass n-butyl acrylate 90 parts by mass β-carboxyethyl acrylate (hereinafter also referred to as “β-CEA”) 11 parts by mass dodecanethiol 6 parts by mass 1,10-decanediol diacrylate 1.5 parts by mass When the temperature of 120c is stabilized, 2% of the weight of the prepared emulsion is added to the polymerization tank 120c over 10 minutes at a back pressure of 150 kPa from the spray-type addition devices 24a and 24b. At that time, the spray-type addition device 24a 24b was added with the emulsion while rotating at 60 rpm. Simultaneously with the addition of the emulsion, 5 parts by mass of ammonium persulfate was diluted 5-fold with ion-exchanged water, added to the polymerization tank 120c at a stirring speed of 160 rpm over 10 minutes, and held for 20 minutes. Next, with the stirring speed kept at 160 rpm, the remaining emulsion was added to the polymerization tank 120c over 3 hours using a spray type addition device 24a, 24b with a back pressure of 150 kPa, and held for another 3 hours after the addition was completed. The reaction was complete. The weight average molecular weight of the obtained resin was 48,000, and the volume average particle diameter was 210 nm.

-Preparation of release agent dispersion (1)-
POLYWAX655 (manufactured by Baker Petrolite Co., Ltd.) 30 parts by weight cationic surfactant (Sanisol B50: manufactured by Kao Corporation) 2 parts by weight ion-exchanged water 70 parts by weight And cooled immediately to obtain a release agent dispersion. The volume average particle diameter of the dispersed wax was 250 nm. The above POLYWAX655 (manufactured by Baker Petrolite) is a polyethylene wax having a number average molecular weight of 655 and a melting point of 99 ° C.

(Preparation of pigment dispersion)
-Preparation of Cyan Colorant Dispersion (1)-
C. I. Pigment Blue 15: 3: manufactured by Dainichi Seika) 30 parts by weight ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 3 parts by weight ion-exchanged water 70 parts by weight The above ingredients are mixed and passed through an ultrasonic disperser for 10 passes. A pigment dispersion was obtained. The number average particle diameter of the dispersed pigment was 130 nm.

-Preparation of black colorant dispersion (2)-
Carbon black (manufactured by Cabot, REGAL 330; primary particle diameter 25 nm, BET specific surface area 94 m ² / g): 90 parts by weight anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC): parts by weight ion-exchanged water : 240 parts by weight The above was mixed, and a black colorant particle dispersion was prepared under the same conditions as the cyan colorant dispersion. The number average particle size of the colorant in the black colorant dispersion was 150 nm.

-Preparation of yellow colorant dispersion (3)-
C. I. Pigment Yellow 74: manufactured by Dainichi Seika Co., Ltd.) 50 parts by mass ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.) 5 parts by mass ion-exchanged water As a result, a colorant dispersion having a number average particle diameter of 168 nm was obtained.

-Preparation of Magenta Colorant Dispersion (4)-
C. I. PigmentRed 122: (manufactured by Clariant) 50 parts by mass ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.) 6 parts by mass ion-exchanged water 200 parts by mass or more) A magenta colorant dispersion having a number average particle size of 185 nm and a solid content of 23.5 parts by weight was obtained.

The following components were charged into the reaction vessel and mixed thoroughly with stirring.
Ion-exchange water: 300 parts by mass Resin particle dispersion (1): 135 parts by mass Colorant dispersion (1): 20 parts by mass Release agent dispersion (1): 30 parts by mass Thereafter, shearing is applied with an ultra turrax. However, 18 parts by mass of a 1% aqueous solution of polyaluminum chloride was gradually added as a flocculant. Since the viscosity of the slurry increased with the addition of the flocculant, the rotational speed of the ultra turrax was increased to a maximum of 7000 rpm, and a dispersion treatment was further performed for 5 minutes after the addition was completed.

  When this slurry was gradually heated with sufficient stirring and maintained at 48 ° C. for 2 hours, the average particle size of the aggregated particles was 5.4 μm. Here, 70 parts by mass of the resin dispersion (1) was newly added slowly over 10 minutes and held for 1 hour. The average particle size of the aggregated particles was 5.0 μm. Next, after adjusting the pH in the reaction tank to 7.0, the temperature is gradually raised to 95 ° C. and held for 4 hours, coalescing of the aggregated particles is performed, and then cooled to 40 ° C. 2 parts by weight of colloidal silica (manufactured by Nippon Aerosil Co., Ltd .: R972) was added to the part, and the mixture was stirred and mixed at 22 m / s for 5 minutes with a Henschel mixer to obtain a cyan toner 1a having a volume average particle size toner of 5.6 μm. . The ratio of the non-colored binder resin particles in 50,000 toners in the toner 1a was 0.2%, and the average shape factor of the non-colored binder resin particles was 105.

  Similarly, except that the black colorant dispersion (2), the yellow colorant dispersion (3), and the magenta colorant dispersion (4) were used in place of the cyan colorant dispersion (1), respectively. In the same procedure, black toner 1b, yellow toner 1c, and magenta toner 1d were obtained. The volume average particle diameter of these toners is 5.6 μm, similar to the cyan toner 1a, and the ratio of the non-colored binder resin particles in 50000 toners in the toners 1b, 1c, and 1d is 0. 4%, yellow toner 1c is 0.1%, and magenta toner 1d is 0.2%. The average shape factor of the non-colored binder resin particles is 104 for black toner 1b, 103 for yellow toner 1c, and magenta toner. 1d was 106.

<Manufacture of toner 2>
-Preparation of resin particle dispersion (2)-
When the addition amount of dodecanethiol is changed to 3 parts by mass, 5 parts by mass of ammonium persulfate is diluted 5 times with ion-exchanged water, the stirring speed is added, and at the same time, 2% of the weight of the emulsion is added to the polymerization tank 120c. The spray type addition devices 24a and 24b were added at a back pressure of 150 kPa, and the spray type addition devices 24a and 24b were prepared according to Example 1 except that the emulsion was added while rotating at 60 rpm. did. The weight average molecular weight of the obtained resin was 94,000, and the volume average particle diameter was 270 nm.

  Thereafter, Toner 2 was prepared in accordance with Toner 1a of Example 1 except that Resin Particle Dispersion (2) was used instead of Resin Particle Dispersion (1). The particle size of the obtained toner was 5.4 μm, the ratio of uncolored binder resin particles in 50000 toners was 0.5%, and the average shape factor of the uncolored binder resin particles was 101. It was.

<Manufacture of toner 3>
-Preparation of resin particle dispersion (3)-
Without adding the addition amount of dodecanethiol, 5 parts by weight of ammonium persulfate was diluted 5 times with ion-exchanged water, and the stirring speed was added. At the same time, 2% of the emulsion weight was added to the polymerization tank 120c. The spray-type addition devices 24a and 24b were added at a back pressure of 150 kPa, and the spray-type addition devices 24a and 24b were prepared in the same manner as in Example 1 except that the emulsion was added while rotating at 60 rpm. The weight average molecular weight of the obtained resin was 197,000, and the volume average particle diameter was 305 nm.

  Thereafter, a toner 3 was produced in accordance with the toner 1a of Example 1 except that the resin particle dispersion (3) was used instead of the resin particle dispersion (1). The particle size of the obtained toner was 5.8 μm, the ratio of uncolored binder resin particles in 50000 toners was 0.8%, and the average shape factor of the uncolored binder resin particles was 103. .

<Manufacture of toner 4>
-Preparation of resin particle dispersion (4)-
The composition is the same as in Example 1, and 5 parts by mass of ammonium persulfate is diluted 5-fold with ion-exchanged water using a polymerization tank 120d, and a stirring speed is added. At the same time, 2% of the weight of the emulsion is added to the polymerization tank 120c. It was produced according to Example 1 except that it was added at a back pressure of 150 kPa using a nozzle type addition device 120d. The weight average molecular weight of the obtained resin was 53,000, and the volume average particle diameter was 220 nm.

  Thereafter, a toner 4 was prepared in the same manner as the toner 1a of Example 1 except that the resin particle dispersion (4) was used instead of the resin particle dispersion (1). The particle size of the obtained toner was 5.8 μm, the ratio of uncolored binder resin particles in 50000 toners was 1.0%, and the average shape factor of the uncolored binder resin particles was 104. It was.

<Manufacture of toner 5>
-Production of resin particle dispersion (5)-
The addition amount of dodecanethiol was changed to 3 parts by mass, and 5 parts by mass of ammonium persulfate was diluted 5 times with ion-exchanged water using a polymerization tank 120d, and a stirring speed was added. At the same time, 2% of the emulsion weight was polymerized. When adding to the tank 120c, it produced according to Example 1 except having added at the back pressure of 150 kPa using the nozzle type | mold addition apparatus 120d. The obtained resin had a weight average molecular weight of 102,000 and a volume average particle diameter of 260 nm.

  Thereafter, a toner 5 was produced in accordance with the toner 1a of Example 1 except that the resin particle dispersion (5) was used instead of the resin particle dispersion (1). The particle size of the obtained toner was 5.6 μm, the ratio of uncolored binder resin particles in 50000 toners was 10.0%, and the average shape factor of the uncolored binder resin particles was 103. It was.

<Manufacture of toner 6>
-Preparation of resin particle dispersion (6)-
Without adding the amount of dodecanethiol, 5 parts by mass of ammonium persulfate was diluted 5 times with ion-exchanged water using the polymerization tank 120d, and the stirring speed was added. At the same time, 2% of the weight of the emulsion was added to the polymerization tank 120c. It was produced according to Example 1 except that it was added at a back pressure of 150 kPa using a nozzle type addition device 120d. The obtained resin had a weight average molecular weight of 201,000 and a volume average particle size of 310 nm.

  Thereafter, a toner 6 was prepared according to the toner 1a of Example 1 except that the resin particle dispersion (6) was used instead of the resin particle dispersion (1). The particle size of the obtained toner was 5.6 μm, the ratio of uncolored binder resin particles in 50000 toners was 22.0%, and the average shape factor of the uncolored binder resin particles was 102. It was.

-Preparation of developers 1a-6-
Volume average particles obtained by coating 7 parts by mass of the toner 1a to toner 7 with 1% by mass of a styrene-methyl methacrylate copolymer (manufactured by Mitsubishi Rayon Co., Ltd .: copolymerization ratio 90:10, Mw: 86000). The mixture was sufficiently stirred and mixed with 93 parts by mass of a ferrite carrier having a diameter of 50 μm to obtain an electrostatic charge image developing developer 7 from the electrostatic charge image developing developer 1a.

[Evaluation methods]
-Actual machine evaluation-
The electrostatic charge image developing developer 1a to the electrostatic charge image developing developer 8 are filled in a developing device, and the toners 1a to 8 are filled in a cartridge. The image was drawn out (modified so as not to have a trickle mechanism). 100 sheets of solid images (3 g / m ² ) were output at high temperature and high humidity (28 ° C and 85% RH environment), and then 1,000 sheets of originals (Japan Imaging Society No. 4 1986) were output continuously. The presence or absence of color loss at the lowest image density portion of the output image was visually confirmed.

  The evaluation standard is that 500 sheets can be accepted, and the more sheets that can be generated, the better. More preferably, the number was 700 or more. Note that 1000 sheets were not recognized to be generated> 1000 sheets, and no output of 1000 sheets or more was performed.

-Amount of deposit on inner wall of polymerization tank-
The inner wall surface of the polymerization tank after 20 batches of the production of the binder resin particle dispersion was visually observed in the polymerization tank.

  These results are shown in Table 1.

  As an application example of the present invention, there is application to an image forming apparatus such as a copying machine or a printer using an electrophotographic system.

FIG. 2 is a schematic diagram illustrating a configuration of an example of a toner manufacturing apparatus according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating a configuration of an example of a polymerization tank of a toner manufacturing apparatus according to an embodiment of the present invention. FIG. 6 is a schematic diagram showing the configuration of another example of the polymerization tank of the toner production apparatus in the embodiment of the present invention. FIG. 6 is a schematic diagram showing the configuration of another example of the polymerization tank of the toner production apparatus in the embodiment of the present invention. It is a schematic diagram which shows a structure of an example of the conventional superposition | polymerization tank of the manufacturing apparatus of a toner. 1 is a schematic diagram illustrating an example of a configuration of an image forming apparatus used in an image forming method of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Polymerizable monomer containing emulsion, 11, 21, 51 Drive source, 12, 22, 52 Stirring means, 13, 23 Temperature sensor, 14 Oil phase supply line, 15 Water phase supply line, 16, 18, 26, 28, 56, 58 Automatic open / close valve, 20 polymerization solution, 24 addition means, 24a, 24b spray-type addition device, 24c guide-type addition device, 24d nozzle-type addition device, 25 polymerizable monomer-containing emulsion supply line, 30 Jacket, 40 Polymerization initiator storage tank, 42 Initiator supply line, 54 Colorant dispersion supply line, 55 Binder resin particle dispersion supply line, 60 Jacket, 100 Emulsification tank, 120, 120a, 120b, 120c, 120d Polymerization Tank, 140 stirring tank, 200 image forming apparatus, 400 housing, 401, 401a to 401d electrophotographic photosensitive member 402, 402a to 402d Charging roll, 403 Exposure device, 404, 404a to 404d Development device, 405a to 405d Toner cartridge, 406 Drive roll, 407 Tension roll, 408 Backup roll, 409 Intermediate transfer belt, 410, 410a to 410d Primary Transfer roll, 411 tray (transfer medium tray), 412 transfer roll, 413 secondary transfer roll, 414 fixing roll, 415a to 415d, 416 cleaning blade, 500 transfer medium.

Claims (8)

A toner containing a binder resin, a colorant, and a release agent;
The toner includes uncolored particles;
A toner for developing electrostatic images, wherein the content of uncolored particles having a shape factor SF1 of 110 or less is less than 1% with respect to the total number of the toners.   2. The static according to claim 1, wherein the non-colored particles have a weight average molecular weight of 40,000 or more and 200,000 or less, and the non-colored particles have a volume average particle size of 4 μm or more and 10 μm or less. Toner for charge image development.   A developer for developing an electrostatic image comprising the toner according to claim 1 and a carrier. A latent image forming unit that forms a latent image on the latent image carrier, a developing unit that develops the latent image using a developer for developing an electrostatic charge, and the developed toner image via an intermediate transfer member or not. An image forming apparatus including: a transfer unit that transfers the toner image on the transfer member; and a fixing unit that adds and fixes the toner image on the transfer member.
The image forming apparatus according to claim 3, wherein the developer for developing an electrostatic charge is the developer for developing an electrostatic charge according to claim 3. A polymerization tank for adding a polymerization initiator and polymerizing a polymerizable monomer to prepare binder resin particles;
An addition means for adding a solution containing the polymerizable monomer at least in the initial stage of polymerization from the gas phase portion of the polymerization tank along the wall of the polymerization tank;
The resin particles and pigment particles are mixed with the obtained resin particle dispersion, a colorant particle dispersion obtained by dispersing at least a colorant, and a release agent particle dispersion obtained by optionally dispersing a release agent. And an agitation tank for coalescing and aggregating the agglomerated particles after the agglomerates and release agent particles are agglomerated to form agglomerated particles. .   6. The apparatus for producing an electrostatic charge developing toner according to claim 5, wherein the adding means is a spray-type adding device or a candy-type adding device.   The solution containing the polymerizable monomer is a polymerizable monomer-containing emulsion prepared by emulsifying an oil phase containing the polymerizable monomer and an aqueous phase. An apparatus for producing a toner for developing electrostatic charge according to claim 6. A step of preparing a polymerizable monomer-containing emulsion by emulsifying an oil phase containing a polymerizable monomer for preparing a binder resin and an aqueous phase while stirring;
At least in the initial stage of polymerization, the polymerizable monomer-containing emulsion is added from the gas phase part of the polymerization tank along the wall of the polymerization tank, and a polymerization initiator is added to the polymerizable monomer-containing emulsion to polymerize. A step of monomer polymerization to prepare binder resin particles;
The binder resin particle dispersion liquid in which the binder resin particles are dispersed, the colorant dispersion liquid in which the colorant is dispersed, and the release agent dispersion liquid in which the release agent is dispersed are mixed to contain the binder resin particles and the colorant. An agglomeration step for agglomerating into toner particle size particles;
A method for producing a toner for developing an electrostatic charge image, comprising: a fusing step of heating and fusing the obtained aggregate to a temperature equal to or higher than the glass transition point of the binder resin particles to form toner particles.

Images