JP2007086314A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which forms an image free from an image quality defect, such as a color streak in a halftone image even when the apparatus is placed in a high temperature environment. <P>SOLUTION: The image forming apparatus having a toner cartridge attached to it includes: a first temperature detecting means whose electric resistance varies in a nonreversible manner at T1[°C] that satisfies relations expressed by Tg-7<T1<Tg-3 and Tg+3<T2<Tg+7, when the glass transition point of a toner is denoted by Tg[°C]; and a second temperature detecting means whose electric resistance varies in a nonreversible manner at T2[°C] that satisfies the relations. The image forming apparatus also has a stirring means for stirring the toner in the main body of the toner cartridge when the main body of the toner cartridge is exposed to a temperature of T1[°C] or above and the electric resistance of the first temperature detecting means varies but the main body of the toner cartridge is not exposed to a temperature of T2[°C] or above and the electric resistance of the second temperature detecting means does not vary. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as an electrophotographic copy, printer, or facsimile.

  In an image forming apparatus used for an electrophotographic system, control of toner density is an important issue for improving image quality. As a method for controlling the toner concentration, the toner is generally supplied to the developing device directly from the toner cartridge or via a hopper, a dispenser or the like in accordance with the toner concentration in the developer and the image density of the print.

  On the other hand, the glass transition point of toner tends to decrease due to the recent demand for low-temperature fixing. If the glass transition point of the toner is lowered, and the toner cartridge is placed in a high temperature environment during storage or transportation, the toner is blocked, and an image quality defect such as color streaking in the process direction occurs on the print. there were.

In order to solve the problem due to storage and transportation in such a high temperature environment, it has a temperature detection means, and this temperature detection means detects the temperature from the time it is manufactured until it is mounted on the image forming apparatus. A process cartridge characterized by this is proposed (see, for example, Patent Document 1).
JP 2003-263022 A

  The present invention relates to an image forming apparatus having a toner cartridge. Even if the toner cartridge is placed at a high temperature due to a change in transportation and storage environment from the time of manufacture to the user, color streaks in a halftone image are disclosed. An object of the present invention is to provide an image forming apparatus that forms an image having no image quality defect.

The above problem is solved by the following means.
That is, the present invention
<1> Development means for developing the electrostatic latent image formed on the image carrier with toner, and transfer means for transferring the developed toner image on the image carrier to a recording medium to form an image. And a toner cartridge main body filled with toner, provided in the toner cartridge main body, a toner carry-out port for carrying out the toner from the toner cartridge main body, and disposed inside the toner cartridge main body and rotated. An image forming apparatus including a toner cartridge having a conveying unit that conveys the toner toward the toner carry-out port while stirring the toner, wherein the toner cartridge body has a glass transition point of the toner as Tg [° C.]. The first temperature detecting means whose electrical resistance changes irreversibly at T1 [° C.] satisfying the following relationship, and T satisfying the following relationship: And a second temperature detecting means whose electric resistance changes irreversibly at 2 [° C.], and the toner cartridge body is exposed to a temperature of T1 [° C.] or more, and the electric resistance of the first temperature detecting means When the toner cartridge main body is not exposed to a temperature of T2 [° C.] or higher and the electric resistance of the second temperature detecting means does not change, the agitation for agitating the toner in the toner cartridge main body An image forming apparatus characterized by comprising means.
-(Tg-7) [° C] <T1 [° C] <(Tg-3) [° C]
-(Tg + 3) [° C] <T2 [° C] <(Tg + 7) [° C]

<2> When the toner cartridge body is exposed to a temperature equal to or higher than T2 [° C.] and the electrical resistance of the second temperature detecting means changes, the stirring means stops stirring the toner in the toner cartridge body. In addition, the image forming apparatus according to <1>, further comprising a display that prompts replacement of the toner cartridge when the electric resistance of the second temperature detection unit changes.

  The present invention relates to an image forming apparatus having a toner cartridge. Even if the toner cartridge is placed at a high temperature due to a change in transportation and storage environment from the time of manufacture to the user, color streaks in a halftone image are disclosed. An image forming apparatus that forms an image having no image quality defect can be provided.

The image forming apparatus of the present invention forms a latent image formed on an image carrier with developing means for developing with toner, and transfers the developed toner image on the image carrier to a recording medium to form an image. A toner cartridge main body that is filled with toner, is provided in the toner cartridge main body, and is provided in the toner cartridge main body, a toner outlet for discharging the toner from the toner cartridge main body, and the toner cartridge main body An image forming apparatus having a toner cartridge having a conveying means for rotating and agitating the toner toward the toner carry-out port, wherein the toner cartridge body has a glass transition point of the toner. When Tg [° C.], the first temperature detecting means whose electric resistance changes irreversibly at T1 [° C.] satisfying the following relationship; And a second temperature detecting means whose electrical resistance changes irreversibly at T2 [° C.] satisfying the relationship, and the toner cartridge body is exposed to a temperature of T1 [° C.] or higher, and the first temperature detection The toner in the toner cartridge main body changes when the electric resistance of the means changes and the toner cartridge main body is not exposed to a temperature of T2 [° C.] or higher and the electric resistance of the second temperature detecting means does not change. It has the stirring means which stirs.
-(Tg-7) [° C] <T1 [° C] <(Tg-3) [° C]
-(Tg + 3) [° C] <T2 [° C] <(Tg + 7) [° C]

  In the image forming apparatus of the present invention, the agitation unit may be configured such that when the toner cartridge main body is exposed to a temperature of T2 [° C.] or more and the electric resistance of the second temperature detection unit is changed, the toner cartridge main body is changed. It is preferable to have a means for stopping the agitation of the toner in the inside and further displaying a message prompting replacement of the toner cartridge when the electric resistance of the second temperature detecting means changes.

  Hereinafter, the present invention will be described in detail with reference to the drawings. Note that members having substantially the same function are given the same reference numerals throughout the drawings, and description thereof is omitted in some cases.

  FIG. 1 is a schematic configuration diagram showing an example of an image forming apparatus of the present invention. FIG. 2 is a schematic bottom view showing the toner cartridge according to the embodiment of the present invention.

  The laser printer 10 as an image forming apparatus according to the present embodiment forms an image (toner image) based on image information input from an external apparatus by a known electrophotographic process, and records the image on a recording sheet or the like. Is.

  The electrophotographic process is a process of charging the electrophotographic photosensitive member, forming an electrostatic latent image by exposure, developing the electrostatic latent image with toner, and transferring the toner image formed on the electrophotographic photosensitive member to a recording material. This is a series of processes in which an image is recorded on a recording material by heat fixing. Note that detailed descriptions of those not directly related to the essence of the present invention will be omitted.

  The laser printer 10 is capable of forming a color image using magenta (M), yellow (Y), black (K), and cyan (C) toners. In the following description, K, Y, M, or C will be added after the reference numerals when displaying the distinction according to each color. (For example, developing device 17Y etc.)

  The laser printer 10 includes four photosensitive drums 11 (Y, M, K, and C) as the photosensitive drum unit 12, a charging roll (not shown) that uniformly charges the surface of the photosensitive drum (image carrier) 11, Each charged surface of each photosensitive drum 11 is individually irradiated with each laser beam Bm corresponding to each of Y, M, K, and C, and an electrostatic latent image of each color corresponding to input information is applied to each photosensitive drum 11. Each color developing device (developing means) as a developing unit 16 that develops an electrostatic latent image on each photosensitive drum 11 by the exposure unit 14 to be formed and forms toner images of each color Y, M, K, and C 17 (Y, M, K, C).

  The laser printer 10 also includes two first intermediate transfer drums 18 and 19 on which the toner images of the respective colors formed on the respective photosensitive drums 11 are primarily transferred electrostatically, and the first intermediate transfer drums 18 and 19. A secondary intermediate transfer drum 20 for electrostatically secondary-transferring each of the multiple toner images respectively formed on the recording medium P, and a transfer roll 22 for transferring the multiple toner images on the secondary intermediate transfer drum 20 to the recording paper P. And a fixing unit 24 for fixing each of the multiple toner images transferred onto the recording paper P onto which the multiple toner images have been transferred.

  Each developing device 17 is supplied with toner as necessary from each toner cartridge 26 (Y, M, K, C) containing toner of four colors by each toner conveying mechanism (conveying means) 28. It has become. Each toner cartridge 26 is detachable. When the toner runs out, it can be replaced with a new toner cartridge 26.

  In the toner transport mechanism 28, a pipe portion 30 formed in a cylindrical shape by a soft synthetic resin having flexibility is attached to a joint portion 29 to which the toner cartridge 26 is connected. Inside the pipe portion 30, a conveying screw member (not shown) is disposed. The pipe portion 30 conveys the toner carried to the joint portion 29 from a toner carry-out port 38 of the toner cartridge main body 36, which will be described later, by this screw member, and supplies the toner to the developing device 17.

  As shown in FIG. 2, the toner cartridge 26 includes a cylindrical toner cartridge main body 36 and side wall portions 36 a and 36 b positioned at both ends of the toner cartridge main body 36.

  A toner carry-out port 38 for carrying the toner toward the developing device 17 is provided on the peripheral surface on one end side of the toner cartridge main body 36.

  Although not shown, a belt portion is slidably attached to the toner cartridge main body 36, and a storage portion for storing the toner carry-out port 38 is provided on the belt portion outside the toner carry-out port 38. Yes. Therefore, when the toner cartridge 26 is not attached to the laser printer 10 (or immediately after attachment), the toner carry-out port 38 is stored in the storage unit, and the toner in the toner cartridge main body 36 leaks out from the toner carry-out port 38. It is not going out.

  The toner cartridge main body 36 includes a first temperature detecting unit 48 whose electric resistance changes irreversibly at T1 [° C.] satisfying the above relationship when the glass transition point of the toner is Tg [° C.], and the relationship And a second temperature detecting means 50 whose electric resistance changes irreversibly at T2 [° C.] satisfying the above.

  When the toner in the toner cartridge main body 36 is exposed to a temperature in the vicinity of the glass transition point when the toner cartridge is stored and transported, the toner causes blocking, and the color in the process direction is formed on the image formed on the recording paper. Image quality defects such as streaks occur. Therefore, when the toner cartridge body 36 is exposed to T1 [° C.] satisfying the relationship of “(Tg-7) [° C.] <T1 [° C.] <(Tg−3) [° C.]”, the toner cartridge body 36 is irreversibly changed. When exposed to the first temperature detecting means 48 whose electrical resistance changes and T2 [° C.] satisfying the relationship of “(Tg + 3) [° C.] <T1 [° C.] <(Tg + 7) [° C.]”, it is irreversible. The toner cartridge body is exposed to a temperature equal to or higher than T1 [° C.], the electrical resistance of the first temperature detecting means 48 changes, and the toner further changes. An agitator (stirring means) 40 is provided for stirring the toner in the toner cartridge body when the cartridge body is not exposed to a temperature of T2 [° C.] or higher and the electrical resistance of the second temperature detecting means 50 does not change. It has been.

  Thus, when the toner cartridge is stored and transported, the toner cartridge main body 36 is exposed to a temperature of T1 [° C.] or higher and is not exposed to a temperature of T2 [° C.] or higher. Thus, image quality defects such as color streaks in the process direction can be prevented from occurring on the image formed on the recording paper due to toner blocking.

  The temperature T1 [° C.] at which the electrical resistance of the first temperature detecting means 48 changes is within the range of “(Tg−7) [° C.] <T1 [° C.] <(Tg−3) [° C.]”. Is essential, and is preferably within the range of “(Tg-6) [° C.] <T1 [° C.] <(Tg-3) [° C.]”, and “(Tg-5) [° C.] <T1 [° C. ] <(Tg-3) [° C.] ”is more preferable. When the temperature range of T1 [° C.] is (Tg-3) [° C.] or less, unnecessary stirring is performed, resulting in an increase in cost. On the other hand, if the temperature range of T1 [° C.] is (Tg−2) [° C.] or more, the toner agitation start temperature is too high, and the process direction appears on the image formed on the recording paper due to toner blocking. The effect of the present invention to prevent the occurrence of image quality defects such as color streaks cannot be obtained.

  Further, the temperature T2 [° C.] at which the electric resistance of the second temperature detecting means 50 changes must be within the range of “(Tg + 3) [° C.] <T2 [° C.] <(Tg + 7) [° C.]”. And within the range of “(Tg + 4) [° C.] <T2 [° C.] <(Tg + 7) [° C.]”, “(Tg + 5) [° C.] <T2 [° C.] <(Tg + 7) [° C.] It is more preferable that it is within the range. When the temperature range of T2 [° C.] is equal to or lower than (Tg + 2) [° C.], the toner cartridge replacement instruction temperature is too low, so that unnecessary toner cartridge replacement is performed, resulting in an increase in cost. Further, the effect of the present invention that prevents the occurrence of image quality defects such as color streaks in the process direction on the image formed on the recording paper due to toner blocking cannot be obtained. On the other hand, if the temperature range of T2 [° C.] is equal to or higher than (Tg + 7) [° C.], a book that prevents image quality defects such as color streaks in the process direction on the image formed on the recording paper due to toner blocking is prevented. The effect of the invention cannot be obtained.

  Examples of the first temperature detecting means 48 and the second temperature detecting means 50 include those obtained by dispersing conductive fine powder in a wax having a melting point at a target temperature (temperature at which electrical resistance changes). . Examples of the conductive fine powder include carbon black (lion Ketjen black product name EC600JD, Mitsubishi Chemical conductive carbon black # 3230B, Tokai conductive carbon black “Toka Black” # 5500, gold, silver, copper, Examples thereof include fine metal powders such as aluminum, lead and tin.

  Examples of the wax include paraffin wax, polyethylene wax, and carnauba wax.

  The first temperature detection means 48 and the second temperature detection means 50 are obtained by injecting a dispersion of the conductive fine powder in wax into a desired mold, cooling to room temperature, and then removing it from the mold. It is done. At this time, the amount of the conductive fine powder dispersed in the wax is preferably 0.01 to 50% by mass, and more preferably 0.1 to 30% by mass.

  The installation positions of the first temperature detection means 48 and the second temperature detection means 50 are not particularly limited as long as they are in contact with the toner cartridge main body 36, and may be installed on the side surface of the toner cartridge main body 36 as shown in FIG. Good.

In the present invention, the glass transition point Tg [° C.] of the toner is determined by a conventional method, for example, using a differential scanning calorimeter (manufactured by Mac Science: DSC3110, thermal analysis system 001: hereinafter abbreviated as “DSC”). The temperature at the rate of temperature increase of 5 ° C./min can be measured, and the temperature of the shoulder on the low temperature side of the endothermic point corresponding to Tg of the obtained chart can be Tg.
On the other hand, the melting point of the wax is determined by following JIS K 0064: 1992.
Further, when the electric resistances of the first temperature detecting means 48 and the second temperature detecting means 50 that change at T1 [° C.] or T2 [° C.] change, the stirring means can detect the amount of change, and Although it will not specifically limit if stirring can be started or complete | finished, It is preferable that the change of an electrical resistance is 10 times or more.

On the other hand, as means for detecting changes in electrical resistance of the first temperature detecting means 48 and the second temperature detecting means 50 in the stirring means, voltage measurement is performed when a constant current I1 [A] is supplied from a constant current supply device. An example is a method of obtaining the electric resistance R1 = V1 / I1 from the voltage V1 [V] measured by the apparatus.
As for the stirring of the toner in the stirring means, an agitator (stirring means) 40 as shown in FIG. The agitator 40 is configured, for example, by bending a metal linear member (for example, stainless steel (SUS304WP)) having a circular cross section in a spiral shape so as to be disposed over substantially the entire area of the toner cartridge body 36. ing. One end of the agitator 40 is connected to the coupling portion, and the other end is a free end that is not constrained.

In the image forming apparatus of the present invention, when the toner cartridge is exposed to a temperature equal to or higher than T2 [° C.] and the electric resistance of the second temperature detecting unit changes, the stirring unit stops stirring the toner in the toner cartridge body. In addition, it is preferable to further include means (not shown) for displaying that prompts replacement of the toner cartridge.
When the toner in the toner cartridge main body 36 reaches a temperature exceeding the glass transition point, the toner causes irreversible blocking, and image quality defects such as color streaks in the process direction occur on the image formed on the recording paper. End up. Therefore, a message prompting replacement of the toner cartridge is displayed.

  Examples of the means for prompting replacement of the toner cartridge include a liquid crystal panel and a light emitting diode.

  In the image forming apparatus of the present invention, as described above, the first temperature detecting means 48 whose electric resistance changes irreversibly at T1 [° C.] and the electric resistance changes irreversibly at T2 [° C.]. The second temperature detection means 50 is provided, but instead of the first temperature detection means 48 and the second temperature detection means 50, a temperature detection means that changes color irreversibly at T1 [° C.] and T2 [ An image forming apparatus having temperature detecting means that changes color irreversibly at [° C.] is also conceivable. In this case, it is necessary to optically read the temperature detection result of the temperature detection means, and it is preferable to optically read the temperature detection result using reflected light.

Existing products can be used as the plurality of temperature detecting means for irreversibly discoloring. For example, temperature measurement sticker made by Ivy Giken Co., Ltd., trade name, temp plate, temperature label made by KN Laboratories, trade name, thermo demand, temperature control temperature indicator made by NOF Corporation, trade name, thermo label-3E, etc. Can be used.
Moreover, the optical detection of the temperature detection result using the reflected light is performed by the reflection type photomicrosensor made by OMRON, trade name EE-SB5, the photo sensor made by ROHM, the trade name RPR-220, and the reflective photo interrupter made by Nippon Aleph. Trade name OM-271 etc. can be used.

  The agitator 40 can also be used as a transport unit that transports the toner toward the toner carry-out port 38 while stirring the toner.

  When the toner cartridge 26 is mounted on the laser printer 10, the coupling unit 44 is connected to a rotational driving force member (not shown) disposed on the laser printer 10 main body side. Then, the coupling portion 44 is rotated by the rotational driving force member, and the rotational force is transmitted to the agitator 40 in the toner cartridge main body 36. The coupling portion 44 can be made of a synthetic resin, for example, POM (polyacetal resin).

  For this reason, the agitator 40 is rotated by applying a rotational force from the coupling portion 44 and transports the toner in the toner cartridge main body 36 toward the toner outlet 38 while stirring.

  Printing of a full-color image by such a laser printer 10 is generally performed as follows.

  First, after the four photosensitive drums 11 are uniformly charged by a charging roll (not shown) in the photosensitive drum unit 12, Y, M, K, and C are transferred from the exposure unit 14 to the surface of each charged photosensitive drum 11. Each laser beam Bm corresponding to each color is irradiated separately, scanned and exposed on each photosensitive drum 11 through a gap of the developing unit 16, and an electrostatic latent image of each color corresponding to input information is formed on each photosensitive drum 11. Is done.

  Next, the electrostatic latent images on the respective photosensitive drums 11 are respectively developed by the developing devices 17 of the respective colors of the developing unit 16 and become toner images of the respective colors Y, M, K, and C.

  Here, the developing device 17 is replenished with toner as needed from each toner cartridge 26 (Y, M, K, C) containing four colors of toner by each toner transport mechanism 28. When supplying the toner, the agitator 40 is rotationally driven to stir and convey the toner inside the toner cartridge main body 36 to the toner carry-out port 38.

  Subsequently, the toner images of the respective colors formed on the respective photosensitive drums 11 are primarily transferred electrostatically onto the first intermediate transfer drums 18 and 19. That is, yellow and magenta toner images formed on the photosensitive drums 11Y and 11M are magenta and yellow in this order on the first intermediate transfer drum 18, and black and cyan toner images formed on the photosensitive drums 11K and 11C are cyan. Then, the toner images are sequentially transferred so as to be superimposed on the first intermediate transfer drum 19 in the order of black. As a result, a multiple toner image composed of a magenta toner image and a yellow toner image is formed on the first intermediate transfer drum 18, while a cyan toner image and a black toner are formed on the first intermediate transfer drum 19. A multiple toner image composed of the image is formed.

  Subsequently, the multiple toner images respectively formed on the first intermediate transfer drums 18 and 19 are electrostatically secondarily transferred onto the secondary intermediate transfer drum 20. As a result, the toner image on the first intermediate transfer drum 18 (M, Y from the lower layer side) and the toner image on the first intermediate transfer drum 18 (C, K from the lower layer side) are placed on the secondary intermediate transfer drum 20. Are transferred in this order to form a multi-toner image in which Y, M, K, and C are superposed from the lower layer side.

  On the other hand, in accordance with the formation of such a toner image, the recording paper P is sent from the paper supply unit 52 toward the transfer roll 22 by the recording paper transport mechanism 54 at a predetermined timing. The recording paper P sent to the transfer roll 22 is gripped by the transfer roll 22 and the secondary intermediate transfer drum 20, and the multiple toner images on the secondary intermediate transfer drum 20 are electrostatically transferred.

  Next, the recording paper P onto which the multiple toner images have been transferred is sent to the fixing unit 24 and passes through the fixing nip portion between the heating roll 24a and the pressure roll 24b of the fixing unit 24, thereby heating and pressing. After the fixing process, the paper is discharged to a paper discharge unit 56 at the top of the laser printer 10.

  A full-color image is formed on one sheet of recording paper P by executing a series of image forming processes as described above.

The toner used in the image forming apparatus of the present invention can be used without particular limitation as long as it is a known toner, such as a toner using a dry method such as a pulverization method or a toner using a wet method such as an emulsion polymerization aggregation method. .
The toner used in the present invention contains at least a binder resin and a colorant. The volume average particle size of the toner is preferably in the range of 2 to 12 μm, more preferably in the range of 2.5 to 9 μm, and still more preferably in the range of 3 to 6 μm.

  Binder resins include 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, and methyl acrylate. , Α-methylene aliphatic monocarboxylic esters such as ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate, vinyl Examples thereof include homopolymers and copolymers of vinyl ethers such as methyl ether, vinyl ethyl ether, and vinyl butyl ether, and vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and vinyl isopropenyl ketone.

  Typical binder resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride copolymer. Examples thereof include coalescence, polyethylene, and polypropylene. Furthermore, polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin wax, and the like can be given.

  Colorants include magnetic powders such as magnetite and ferrite, carbon black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, 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 is a typical example.

  The toner may be internally added or externally added with a known additive such as a charge control agent, a release agent, or other inorganic fine particles. Typical examples of the release agent include low molecular weight polyethylene, low molecular weight polypropylene, Fischer-Tropsch wax, montan wax, carnauba wax, rice wax, and candelilla wax.

  Known charge control agents can be used, but azo metal complex compounds, metal complex compounds of salicylic acid, and resin type charge control agents containing polar groups can be used. When the toner is manufactured by a wet manufacturing method, it is preferable to use a material that is difficult to dissolve in water in terms of controlling ionic strength and reducing wastewater contamination.

As other inorganic fine particles, small-diameter inorganic fine particles having an average primary particle diameter of 40 nm or less are used for the purpose of powder flowability, charge control, etc., and if necessary, larger diameters are used to reduce adhesion. These inorganic or organic fine particles may be used in combination. As these other inorganic fine particles, known ones can be used. Examples thereof include silica, alumina, titania, metatitanic acid, zinc oxide, zirconia, magnesia, calcium carbonate, magnesium carbonate, calcium phosphate, cerium oxide, and strontium titanate.
In addition, the surface treatment of the small-diameter inorganic fine particles is effective because the dispersibility becomes high and the effect of increasing the powder fluidity increases.

The toner used in the present invention is not particularly limited by the production method, and can be obtained by a known method.
Specifically, for example, in addition to a binder resin and a colorant, a kneading and pulverizing method in which a release agent, a charge control agent, and the like are kneaded, pulverized, and classified as necessary, and particles obtained by the kneading and pulverizing method are machined. The shape is changed by mechanical impact force or thermal energy, the polymerizable monomer constituting the binder resin is emulsion-polymerized, and the formed dispersion and the dispersion containing the colorant are separated as necessary. Emulsion polymerization aggregation method to obtain a spherical toner by mixing with a dispersion liquid such as a mold agent and a charge control agent, and agglomeration, heat fusion, a polymerizable monomer to obtain a binder resin, a colorant, and the like Depending on the suspension polymerization method in which a solution of a release agent, a charge control agent, etc. is suspended in an aqueous solvent for polymerization, a binder resin and a colorant, and if necessary, a solution of a release agent, a charge control agent, etc. Examples thereof include a dissolution suspension method in which particles are suspended in a solvent and granulated.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In the following examples, “part” means “part by mass” unless otherwise specified.
Example 1
90 parts of paraffin wax having a melting point of 46 ° C. are weighed in a beaker, heated to 80 ° C. in an oil bath, and 10 parts of Lion Ketjen Black product name EC600JD is stirred, poured into a cylindrical mold with a diameter of 1 mm, cooled to room temperature, After taking out from the mold, it was cut to a length of 10 mm, and a copper wire was attached to the end to obtain a first temperature detecting means. Also, weigh 90 parts of paraffin wax with a melting point of 56 ° C. in a beaker, heat to 80 ° C. in an oil bath, add 10 parts of Lion Ketjen Black product name EC600JD, stir, inject into a cylindrical mold with a diameter of 1 mm and bring it to room temperature. After removing from the mold, it was cut to a length of 10 mm, a copper wire was attached to the end, and a second temperature detecting means was obtained.

  The obtained first temperature detection means and second temperature detection means were attached to the toner cartridge wall surface for DocuPrint C2424 (DPC2424). On the other hand, when the toner cartridge is inserted into the toner cartridge insertion portion of the DPC 2424, an electrical resistance change detection portion (electrode, constant current) for reading the electrical resistance change of the first temperature detection means and the second temperature detection means. Supply device, voltage measuring device). The electrical resistance change detection unit changes the electrical resistance of the first temperature detection means by 10 times or more, and when the electrical resistance of the second temperature detection means does not change, the toner agitator in the toner cartridge agitates the toner. When the electric resistance of the second temperature detecting means changed by 10 times or more, the toner agitation was stopped and the display was urged to replace the cartridge (light emitting diode turned on). The first temperature detecting means changed in electric resistance at 46 ° C., and the second temperature detecting means changed in electric resistance at 56 ° C.

  Seven toner cartridges prepared as described above were prepared, and each toner cartridge was filled with toner (glass transition temperature: 50 ° C.), and 40 ° C. 1 Hr, 45 ° C. 1 Hr, 48 ° C. 1 Hr, 50 ° C. 1 Hr, 55 ° C. Seven toner cartridges were prepared by heat treatment under the conditions of 1 hour, 58 ° C., 1 hour, and 60 ° C., 1 hour. When seven heat-treated toner cartridges are mounted on the modified DPC 2424 and 1000 sheets of half-tone images with an image density of 50% are printed on A4 paper continuously with 1000%, the number of color streaks is calculated. It was measured. When a message prompting replacement of the toner cartridge is displayed, the toner cartridge is replaced with a toner cartridge that has not been heat-treated.

  As a result, even when a toner cartridge heat-treated at 40 ° C. for 1 hour was installed, the toner was not stirred, but no color streaking occurred. Further, even when a toner cartridge heat-treated at 45 ° C. for 1 hour was mounted, the toner was not stirred, but no color streak occurred. When a toner cartridge heat-treated at 48 ° C. for 1 hour was mounted, the toner was agitated and no color streaking occurred. When a toner cartridge heat-treated at 50 ° C. for 1 hour was mounted, the toner was agitated and no color streaking occurred. When a toner cartridge heat-treated at 55 ° C. for 1 hour was mounted, the toner was agitated and no color streaking occurred. When a toner cartridge that had been heat-treated at 58 ° C. for 1 hour was mounted, a message prompting the user to replace the toner cartridge was displayed. When a toner cartridge that had been heat-treated at 60 ° C. for 1 hour was mounted, a message prompting the user to replace the toner cartridge was displayed. The modified machine of DPC 2424 has a developing unit and a transfer unit.

(Example 2)
In order to obtain the first temperature detection means, paraffin wax having a melting point of 44 ° C. is used instead of the paraffin wax having a melting point of 46 ° C., and in order to obtain the second temperature detection means, the melting point instead of the paraffin wax having a melting point of 56 ° C. A first temperature detecting means and a second temperature detecting means were obtained in the same manner as in Example 1 except that 54 ° C. paraffin wax was used.
The obtained first temperature detection means and second temperature detection means were attached to the toner cartridge wall surface for DocuPrint C2424 (DPC2424). On the other hand, when the toner cartridge is inserted into the toner cartridge insertion portion of the DPC 2424, an electrical resistance change detection portion (electrode, constant current) for reading the electrical resistance change of the first temperature detection means and the second temperature detection means. Supply device, voltage measuring device). The electrical resistance change detection unit changes the electrical resistance of the first temperature detection means by 10 times or more, and when the electrical resistance of the second temperature detection means does not change, the toner agitator in the toner cartridge agitates the toner. When the electric resistance of the second temperature detecting means changed by 10 times or more, the toner was agitated and the display was urged to replace the cartridge (light emitting diode turned on). The first temperature detecting means changed in electric resistance at 44 ° C., and the second temperature detecting means changed in electric resistance at 54 ° C.

  Seven toner cartridges prepared as described above were prepared, and each toner cartridge was filled with toner (glass transition temperature: 50 ° C.), and 40 ° C. 1 Hr, 45 ° C. 1 Hr, 48 ° C. 1 Hr, 50 ° C. 1 Hr, 55 ° C. Seven toner cartridges were prepared by heat treatment under the conditions of 1 hour, 58 ° C., 1 hour, and 60 ° C., 1 hour. When seven toner cartridges heat treated in the same manner as in Example 1 were mounted on the modified DPC 2424, a halftone image with an image density of 50% was printed continuously on A4 paper on an A4 sheet of 10% area ratio. The number of color streaks was measured. When a message prompting replacement of the toner cartridge is displayed, the toner cartridge is replaced with a toner cartridge that has not been heat-treated.

  As a result, even when a toner cartridge heat-treated at 40 ° C. for 1 hour was installed, the toner was not stirred, but no color streaking occurred. When a toner cartridge heat-treated at 45 ° C. for 1 hour was mounted, the toner was agitated and no color streak occurred. When a toner cartridge heat-treated at 48 ° C. for 1 hour was mounted, the toner was agitated and no color streaking occurred. When a toner cartridge heat-treated at 50 ° C. for 1 hour was mounted, the toner was agitated and no color streaking occurred. When a toner cartridge that had been heat-treated at 55 ° C. for 1 hour was installed, a message prompting the user to replace the toner cartridge was displayed. When a toner cartridge that had been heat-treated at 58 ° C. for 1 hour was mounted, a message prompting the user to replace the toner cartridge was displayed. When a toner cartridge that had been heat-treated at 60 ° C. for 1 hour was mounted, a message prompting the user to replace the toner cartridge was displayed. The modified machine of DPC 2424 has a developing unit and a transfer unit.

(Example 3)
In order to obtain the first temperature detection means, paraffin wax having a melting point of 56 ° C. is used instead of the paraffin wax having a melting point of 46 ° C., and in order to obtain the second temperature detection means, the melting point instead of the paraffin wax having a melting point of 56 ° C. A first temperature detecting means and a second temperature detecting means were obtained in the same manner as in Example 1 except that 66 ° C. paraffin wax was used.
The obtained first temperature detection means and second temperature detection means were attached to the toner cartridge wall surface for DocuPrint C2424 (DPC2424). On the other hand, when the toner cartridge is inserted into the toner cartridge insertion portion of the DPC 2424, an electrical resistance change detection portion (electrode, constant current) for reading the electrical resistance change of the first temperature detection means and the second temperature detection means. Supply device, voltage measuring device). The electrical resistance change detection unit changes the electrical resistance of the first temperature detection means by 10 times or more, and when the electrical resistance of the second temperature detection means does not change, the toner agitator in the toner cartridge agitates the toner. When the electric resistance of the second temperature detecting means changed by 10 times or more, the toner was agitated and the display was urged to replace the cartridge (light emitting diode turned on). In the first temperature detecting means, the electric resistance changed at 56 ° C., and the electric resistance changed at the second temperature detecting hand 66 ° C.

Three toner cartridges prepared as described above were prepared, and each toner cartridge was filled with toner (glass transition temperature: 60 ° C.) and heat-treated under the conditions of 40 ° C. 1 Hr, 50 ° C. 1 Hr, and 60 ° C. 1 Hr 3 Toner cartridges were prepared. When three heat-treated toner cartridges are mounted on the modified DPC 2424 machine, the number of color streaks when a 1000 halftone image with an image density of 50% is printed on A4 paper continuously with an area ratio of 10% is calculated. It was measured. When a message prompting replacement of the toner cartridge is displayed, the toner cartridge is replaced with a toner cartridge that has not been heat-treated.
As a result, even when a toner cartridge heat-treated at 50 ° C. for 1 hour was mounted, the toner was not stirred, but no color streaking occurred. Further, when a toner cartridge heat-treated at 60 ° C. for 1 hour was mounted, the toner was agitated and no color streak occurred. When a toner cartridge that was heat-treated at 70 ° C. for 1 hour was installed, a message prompting the user to replace the toner cartridge was displayed. The modified machine of DPC 2424 has a developing unit and a transfer unit.

(Comparative Example 1)
When preparing seven toner cartridges for DocuPrint C2424 (DPC2424) as an image forming apparatus, filling each toner cartridge with toner (glass transition temperature: 50 ° C.), and printing 1000 sheets in the same manner as in Example 1. The number of generated color streaks was measured. As a result, no color streak occurred when the toner cartridge heat-treated at 40 ° C. for 1 hour was installed. Further, when a toner cartridge heat-treated at 45 ° C. for 1 hour was installed, no color streak occurred. In addition, when a toner cartridge heat-treated at 48 ° C. for 1 hour was mounted, five color streaks were confirmed. When the toner cartridge heat-treated at 50 ° C. for 1 hour was mounted, ten color streaks were confirmed. When a toner cartridge heat-treated at 55 ° C. for 1 hour was mounted, 100 color streaks were confirmed. When a toner cartridge heat-treated at 58 ° C. for 1 hour was installed, 500 color streaks were confirmed. When a toner cartridge heat-treated at 60 ° C. for 1 hour was mounted, 1000 color streaks were confirmed.

(Comparative Example 2)
In order to obtain the first temperature detection means, paraffin wax having a melting point of 49 ° C. is used instead of the paraffin wax having a melting point of 46 ° C., and in order to obtain the second temperature detection means, instead of the paraffin wax having a melting point of 56 ° C. A first temperature detecting means and a second temperature detecting means were obtained in the same manner as in Example 1 except that paraffin wax having a melting point of 59 ° C. was used.
The obtained first temperature detection means and second temperature detection means were attached to the toner cartridge wall surface for DocuPrint C2424 (DPC2424). On the other hand, when the toner cartridge is inserted into the toner cartridge insertion portion of the DPC 2424, an electrical resistance change detection portion (electrode, constant current) for reading the electrical resistance change of the first temperature detection means and the second temperature detection means. Supply device, voltage measuring device). The electrical resistance change detection unit changes the electrical resistance of the first temperature detection means by 10 times or more, and when the electrical resistance of the second temperature detection means does not change, the toner agitator in the toner cartridge agitates the toner. When the electric resistance of the second temperature detecting means changed by 10 times or more, the toner was agitated and the display was urged to replace the cartridge (light emitting diode turned on). The first temperature detecting means changed in electric resistance at 49 ° C., and the second temperature detecting means changed in electric resistance at 59 ° C.

  Seven toner cartridges prepared as described above were prepared, and each toner cartridge was filled with toner (glass transition temperature: 50 ° C.), and 40 ° C. 1 Hr, 45 ° C. 1 Hr, 48 ° C. 1 Hr, 50 ° C. 1 Hr, 55 ° C. Seven toner cartridges were prepared by heat treatment under the conditions of 1 hour, 58 ° C., 1 hour, and 60 ° C., 1 hour. When seven heat-treated toner cartridges are mounted on the modified DPC 2424 and 1000 sheets of halftone images with an image density of 50% are continuously printed on A4 paper with an area ratio of 10%, the number of color streaks generated is shown. It was measured. When a message prompting replacement of the toner cartridge is displayed, the toner cartridge is replaced with a toner cartridge that has not been heat-treated.

  As a result, even when a toner cartridge heat-treated at 40 ° C. for 1 hour was installed, the toner was not stirred, but no color streaking occurred. Even when a toner cartridge heat-treated at 45 ° C. for 1 hour was mounted, the toner was not stirred, but no color streak occurred. When a toner cartridge heat-treated at 48 ° C. for 1 hour was mounted, the toner was not stirred and five color streaks were observed. When a toner cartridge heat-treated at 50 ° C. for 1 hour was mounted, the toner was agitated and no color streaking occurred. When a toner cartridge heat-treated at 55 ° C. for 1 hour was mounted, the toner was agitated and no color streaking occurred. When a toner cartridge heat-treated at 58 ° C. for 1 hour was mounted, the toner was stirred, but 300 color streaks were observed. When a toner cartridge that had been heat-treated at 60 ° C. for 1 hour was mounted, a message prompting the user to replace the toner cartridge was displayed. The modified machine of DPC 2424 has a developing unit and a transfer unit.

(Comparative Example 3)
When three toner cartridges for DocuPrint C2424 (DPC2424) are prepared as image forming apparatuses, and each toner cartridge is filled with toner (glass transition temperature: 60 ° C.), and 1000 sheets are continuously printed as in the third embodiment. The number of generated color streaks was measured. As a result, no color streak occurred when a toner cartridge heat-treated at 50 ° C. for 1 hour was installed. When a toner cartridge heat-treated at 60 ° C. for 1 hour was installed, ten color streaks were confirmed. When a toner cartridge heat-treated at 70 ° C. for 1 hour was mounted, 1000 color streaks were confirmed.

1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a schematic bottom view showing the toner cartridge according to the embodiment of the invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Laser printer 11 Photosensitive drum 12 Photosensitive drum unit 14 Exposure unit 16 Development unit 17 Development apparatus 18 Primary intermediate transfer drum 19 Primary intermediate transfer drum 20 Secondary intermediate transfer drum 22 Transfer roll 24 Fixing unit 26 Toner cartridge 28 Toner conveyance mechanism 29 Joint part 30 Pipe unit 36 Toner cartridge main body 38 Toner carry-out port 40 Agitator 44 Coupling unit 48 First temperature detection unit 50 Second temperature detection unit 52 Paper feed unit 54 Recording paper transport mechanism 56 Paper discharge unit

Claims (2)

A developing means for developing the electrostatic latent image formed on the image carrier with toner, and a transfer means for transferring the developed toner image on the image carrier to a recording medium to form an image;
A toner cartridge main body filled with toner, a toner cartridge outlet provided in the toner cartridge main body for discharging the toner from the toner cartridge main body, and a toner cartridge main body disposed in the toner cartridge main body, and rotating to remove the toner An image forming apparatus comprising a toner cartridge having a conveying means for conveying toward the toner carry-out port while stirring,
The toner cartridge body has the following relationship with the first temperature detecting means in which the electrical resistance changes irreversibly at T1 [° C.] satisfying the following relationship when the glass transition point of the toner is Tg [° C.]. A second temperature detecting means whose electrical resistance changes irreversibly at a satisfactory T2 [° C.], and the toner cartridge body is exposed to a temperature of T1 [° C.] or higher, and the first temperature detecting means When the electrical resistance changes and the toner cartridge body is not exposed to a temperature of T2 [° C.] or higher, and the electrical resistance of the second temperature detecting means does not change, the toner in the toner cartridge body is agitated. An image forming apparatus comprising a stirring means for performing the above operation.
(Tg-7) [° C] <T1 [° C] <(Tg-3) [° C]
-(Tg + 3) [° C] <T2 [° C] <(Tg + 7) [° C]   The stirring means stops the stirring of the toner in the toner cartridge body when the toner cartridge body is exposed to a temperature of T2 [° C.] or more and the electric resistance of the second temperature detection means changes. 2. The image forming apparatus according to claim 1, further comprising means for prompting replacement of the toner cartridge when the electric resistance of the second temperature detecting means changes.

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