JP4844266B2 - Image forming apparatus - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus and an image forming method employing an electrostatic recording method, and an image forming apparatus and an image forming apparatus using toner capable of developing different colors by exposing light of different wavelengths. It is about the method.

  2. Description of the Related Art Conventionally, in a recording apparatus that obtains a color image by an electrophotographic method, the basic three primary colors are developed according to each image information, and these toner images are sequentially superimposed to obtain a color image. As a specific apparatus configuration, a so-called four-cycle machine that obtains a color image by repeatedly developing each color on a photosensitive drum on which a latent image is formed by an image forming method and transferring them to a transfer member, Alternatively, a tandem machine or the like that includes a photosensitive drum and a developing device for each color image forming unit and transfers a toner image successively and sequentially to obtain a color image by moving a transfer member.

  These are at least common by having a plurality of developing devices for each color. For this reason, in normal color image formation, four developing devices in which black is added to the three primary colors are required, and in the tandem machine, four photosensitive drums are required for each of the four developing devices. An increase in the size and cost of the apparatus is inevitable, for example, a means for matching the synchronization of the forming means is required.

On the other hand, a method for obtaining a color image with a single developing device has been proposed (see, for example, Patent Documents 1 and 2). Since the toner used in these has a color recording sensitivity of about 0.1 to 0.2 mJ / cm ² , naturally, in the image forming apparatus using the toner, external light, internal stray light, The properties of other light sources are significantly altered. Therefore, unnecessary light irradiation must be avoided when the toner is used in any state.

However, in an ordinary image forming apparatus, there are many opportunities to expose the inside of the apparatus to external light, such as during various maintenances and during recovery from a paper jam. In this case, if the developing device is taken out when it is shielded from light when opening the device, and further separated into a light-shielded container such as a dark box and then entered into each operation, the procedure becomes complicated and the time required is ignored. However, there is a demand for a solution to such a problem for the practical application of the image forming apparatus using the toner as described above.
JP-A 63-131364 JP 2003-330228 A

The object of the present invention is to solve the above-mentioned problems of the prior art.
That is, according to the present invention, even when a toner capable of controlling color development or non-color development according to color development information by light is used, apparatus maintenance can be performed without exposing the toner to external light. An object of the present invention is to provide an image forming apparatus and an image forming method capable of performing recovery from trouble such as a paper jam or the like.

The above-mentioned subject is achieved by the following present invention. That is, the present invention
<1> An image forming apparatus using toner that is controlled so as to maintain a colored state or a non-colored state by providing coloring information by light,
An image carrier, means for forming a latent image on the surface of the image carrier, developing means for converting the latent image into a toner image with a developer containing toner, and light on the toner image formed on the surface of the image carrier. Coloring information imparting means for imparting coloration information by means of, a transfer means for transferring the toner image to which the coloration information is imparted to the surface of the recording medium, and fixing the toner image transferred to the surface of the recording medium by heat and / or pressure Fixing means for performing color development, and color development means for coloring the toner image to which the color development information is imparted by heating,
The image forming apparatus further includes a light shielding unit that shields the developer in the developing unit from light existing inside the apparatus.

  Since the image forming apparatus can obtain a full-color image with one image carrier and one developer, the apparatus can be significantly downsized. However, since the toner used for this has high color recording sensitivity, it is necessary to avoid light exposure due to unnecessary light irradiation before color information is given. On the other hand, according to the above configuration, the exposure of the toner to the external light can be prevented by shielding (shielding) the photochromic toner or the developer containing the toner before the apparatus main body is opened and exposed to light.

<2> The image forming apparatus according to <1>, wherein the light shielding unit is attached to the developing unit.

  If the light shielding means is attached to the developing means, the above object can be achieved reliably, and the mechanism can be made as simple and compact as possible. As this aspect, the mechanisms listed below are preferable.

<3> The image forming apparatus according to <1>, wherein the light shielding unit includes an openable and closable shutter that shields at least an opening facing the image carrier of a developing unit that stores toner in the developing unit. .

<4> The image forming apparatus according to <3>, wherein the light shielding unit includes a mechanism that opens the shutter when the developing unit performs development on the image carrier.

<5> The method according to <3>, wherein the light shielding unit moves the developer unit to a side away from the image carrier before or during the operation of closing the opening of the developer unit with the shutter. An image forming apparatus.

<6> The item <3>, in which the light shielding unit moves the developing unit to a side closer to the image carrier after opening or opening the shutter of the opening of the developing unit. This is an image forming apparatus.

<7> The image forming apparatus according to <1>, wherein the light-shielding unit includes a mechanism that peels off the developer on at least an image carrier-facing surface of the developer-carrying member in the developing unit.

<8> The light shielding unit according to <1>, wherein the light shielding unit includes a mechanism that applies a voltage to an electrode provided in the vicinity of the surface of the developer carrying member in the developing unit and removes toner on the surface of the developer carrying member. An image forming apparatus.

<9> The image forming apparatus according to <1>, wherein the light shielding unit includes a mechanism for retracting at least the developing unit to a light shielding section.

  For example, if the entire developer unit is retracted to the light-shielding section, it is possible to avoid exposure to the developer light inside due to light leakage from the developer unit. However, it is more preferable because the toner hardly deteriorates.

<10> The image forming apparatus according to <1>, wherein the light shielding unit performs the shielding operation according to an instruction signal from the outside or a signal based on an operation for maintaining the inside of the apparatus.

  Since the light shielding step is not always performed but is performed as necessary, it is preferable that a signal for performing light shielding is transmitted artificially or in conjunction with a maintenance operation.

<11> A photocurable composition comprising a first component and a second component that are present in a state where the toners are separated from each other and react with each other, and any one of the first component and the second component <1>, wherein the photocurable composition is maintained in a cured or uncured state by providing color development information by light, and the reaction for color development is controlled. An image forming apparatus.

As the toner in the present invention, as described above, for example, when color development information by light called a color development portion is given in a binder resin, it is possible to develop a specific color (or maintain a non-color development state). If a construction having one or more continuous regions (possible) is used, the light-receiving portion receives light, so that the light-receiving efficiency of one toner particle can be increased, and the color-forming efficiency is higher than that of other toners. Can be high.
In order to make full use of such toner in an actual apparatus, an image forming apparatus provided with a light shielding unit as in the present invention is required.

<12> An image forming apparatus using a toner that is controlled so as to maintain a colored state or a non-colored state by providing coloring information by light,
An image carrier, means for forming a latent image on the surface of the image carrier, developing means for converting the latent image into a toner image with a developer containing toner, and light on the toner image formed on the surface of the image carrier. Coloring information imparting means for imparting coloration information by means of, a transfer means for transferring the toner image to which the coloration information is imparted to the surface of the recording medium, and fixing the toner image transferred to the surface of the recording medium by heat and / or pressure Fixing means for performing color development, and color development means for coloring the toner image to which the color development information is imparted by heating,
The image forming apparatus further includes a developer removing unit that removes at least unnecessary toner from the developer on the surface of the developer carrying member in the developing unit.

In the apparatus using toner according to the present invention, for the apparatus opening at the time of an apparatus trouble such as maintenance, basically, it is sufficient that the toner is not present in the portion exposed from the developing unit. In addition to the light shielding, the above means for removing the toner in the exposed portion also works effectively.
As such a mechanism, the following aspects are preferable.

<13> The developer removing unit develops and transfers unnecessary toner on the surface of the developer carrying member to the image carrying member before performing new image formation after an operation for maintaining the inside of the apparatus. <12> The image forming apparatus according to <12>, further including a mechanism for recovering to a cleaner.

<14> Before the developer removing unit performs a new image formation after an operation for maintaining the inside of the apparatus, the developer carrying member is driven to rotate for a predetermined time so that the surface of the developer carrying member is unnecessary. <12> The image forming apparatus according to <12>, further including a mechanism for dispersing toner in a developer in a developing unit.

<15> A photocurable composition comprising the first component and the second component that are present in a state where the toners are isolated from each other and react with each other, and any one of the first component and the second component <12>, wherein the photocurable composition is maintained in a cured or uncured state by the application of color development information by light, and the reaction for color development is controlled. An image forming apparatus.

  The mechanism for removing the toner at the exposed portion is sufficiently effective for using the toner having the high color recording sensitivity as described above.

<16> An image forming method using a toner that is controlled to maintain a colored state or a non-colored state by providing coloring information by light,
A toner image forming step for forming a toner image on the surface of the image carrier, a color information providing step for imparting color information by light to the toner image formed on the surface of the image carrier, and a toner image to which the color information is added A transfer step for transferring the toner image to the surface of the recording medium, a fixing step for fixing the toner image transferred to the surface of the recording medium by heat and / or pressure, and a color development step for coloring the toner image to which the color development information is given by heating. And including
The image forming method further includes a light shielding step of shielding the developer in the developing unit from light existing inside the apparatus.

<17> An image forming method using a toner that is controlled to maintain a colored state or a non-colored state by providing coloring information by light,
A toner image forming step for forming a toner image on the surface of the image carrier, a color information providing step for imparting color information by light to the toner image formed on the surface of the image carrier, and a toner image to which the color information is added A transfer step for transferring the toner image to the surface of the recording medium, a fixing step for fixing the toner image transferred to the surface of the recording medium by heat and / or pressure, and a color development step for coloring the toner image to which the color development information is given by heating. And including
The image forming method further includes a developer removing step of removing at least unnecessary toner from the developer on the surface of the developer carrying member in the developing unit.

  According to the present invention, even when a toner capable of controlling color development or non-color development according to color development information by light is used, apparatus maintenance can be performed without exposing the toner to external light. It is possible to provide an image forming apparatus and an image forming method capable of easily recovering from problems such as paper jams.

Hereinafter, the present invention will be described in detail.
The first image forming apparatus (image forming method) of the present invention (hereinafter sometimes referred to as “first present invention”) maintains a colored state or a non-colored state by providing coloring information by light. An image forming apparatus (image forming method) using toner to be controlled, comprising an image carrier, means for forming a latent image on the surface of the image carrier (latent image forming step), and the latent image containing toner Development means (development process) for forming a toner image with a developer, color development information provision means (color development information provision process) for imparting color development information by light to the toner image formed on the surface of the image carrier, and the color development information Transfer means for transferring the applied toner image to the surface of the recording medium (transfer process); Fixing means for fixing the toner image transferred to the surface of the recording medium by heat and / or pressure (fixing process); Toner with coloring information And coloring means for coloring the (coloring step), wherein the further characterized by having a light shielding means (shading process) to shield from light that exists within the developer apparatus in the developing unit.

  The second image forming apparatus (image forming method) of the present invention (hereinafter also referred to as “second present invention”) has the same configuration as described above, and further includes a developer carrier in the developing means. It has a developer removing means (developer removing step) for removing at least unnecessary toner from the developer on the surface.

  The toner used in the present invention has a function of maintaining a state in which, for example, when each toner particle is exposed to light of a different wavelength, the color is developed according to the wavelength, or the color is not developed (non-colored). is doing. That is, the toner has a chromogenic substance (and a color developing portion including this) that can develop color by providing color development information by light, and the toner can develop color or non-color by the application of color development information by light. It is controlled to maintain this state.

Here, the “applying color development information by light” refers to a desired region of a toner image in order to control the color development / non-color development state and the color tone upon color development in units of individual toner particles constituting the toner image. On the other hand, it means that one or more kinds of light having a specific wavelength are selectively given, or no light is given.
Such a toner is not particularly limited as long as it can exhibit the above functions, and examples thereof include toners described in Patent Documents 1 and 2 and toners preferably used in the present invention described later.

  In the image forming apparatus (image forming method) using the toner, such a toner is mounted on one developing device, and four types of cyan (C), magenta (M), yellow (Y), and black (K) are used. An electrostatic latent image is formed on the image carrier by the logical sum of the color image formation information, and the electrostatic latent image is developed with the toner to form a toner image. Thereafter, light having a wavelength corresponding to the color information is obtained. Then, the toner image is exposed to give color development information to the toner image. Thereafter, the toner image to which the coloring information is given is transferred to a recording medium, and then fixed to the recording medium by heat and pressure. At this time, the color reaction of the toner is performed by the heat, and a color image is obtained.

  Accordingly, since a full color image can be obtained with one image carrier and one developing device, the size of the main body of the image forming apparatus is as close as possible to that of a monochrome printer, and the apparatus can be miniaturized. Become. In addition, since it is not necessary to layer toner for each color when forming a toner image, unevenness of the image surface can be suppressed, the gloss of the image surface can be made uniform, and the toner can be colored with a pigment or the like. Since no agent is used, it is possible to obtain a silver salt-like image.

  However, since the toner used in the present invention has the color development recording sensitivity as described above, it is necessary to avoid light exposure (state in which color development cannot be performed or incomplete color development) due to unnecessary light irradiation prior to color information provision. . Therefore, in an image forming apparatus using this toner, it is necessary to sufficiently shield the light inside the apparatus not only at the time of image formation in a conventional electrophotographic process machine, but also at other times. Care must be taken for internal and external handling.

  On the other hand, in many printing apparatuses such as electrophotographic apparatuses, periodic maintenance is still essential to maintain the performance quality, and the frequency of defects such as paper jams has decreased due to recent technological advances. However, many of the problems are still not solved. Envisioning a complete printing device that is free of defects and completely maintenance-free requires enormous costs, even if it is feasible, and the size and complexity of the device are inevitable. It is expected to be.

  Under such circumstances, in general, a container (developer unit) containing toner is normally sealed from the viewpoint of preventing scattering, etc., and is configured as a shield when replenishing toner or as an integral cartridge. Although there is little risk of light exposure to the toner, the developer carried on the surface of the developer carrying body for development on the image carrying body may be detached from the developer unit during maintenance, paper jam handling, etc. There is a high possibility that the apparatus main body is inspected and exposed to external light. The toner exposed to external light cannot develop color or remains in an incomplete state even in the color development step after the subsequent steps.

  In view of this point, the inventors of the present invention prevent the toner from being exposed to external light by shielding and shielding the light-colored toner or the developer containing the toner before the apparatus main body is opened and exposed to light. Has been found to be effective or most realistic (first invention). That is, it has been found that providing a mechanism for shielding the photochromic toner or the developer containing the toner when the inside of the apparatus main body is opened for maintenance or the like is effective in preventing the photodegradation of the toner.

  Furthermore, once the light exposure is received, the state is left as it is and the next image formation is performed. As a result, a toner image is formed in a state where the light-degraded toner is mixed, resulting in image quality defects. Since it will generate | occur | produce, it is not preferable. From this point of view, in the present invention, when the developer is exposed to the light, only the developer or the exposed toner in the developer is removed from the system before proceeding to the next image formation. It has also been found that removal is effective (second invention).

  Specifically, the developer that is normally exposed to light is a developer in a state where it is used for development like the developer on the surface of the developer carrying member in the developing means, and therefore, after exposure to light In a state where the developer is not exposed to light, it is possible to provide a mechanism for removing only the light exposed toner (unnecessary toner) in the developer on the surface of the developer carrying member without wasting the developer and quickly. It was found to be effective in returning to the state before light exposure.

  The first and second aspects of the present invention will be described below. The two aspects of the present invention relate to the overall image forming process, the light-shielding step in the first aspect, and the developer removal in the second aspect. Since the process is the same except that the process is added, first, each process in the image forming process common to both inventions will be described.

The image forming process to which the present invention is applied is not particularly limited, such as a so-called electrophotographic process or a process (ionography) for forming an electrical latent image with ions or the like on a dielectric. First, an image forming apparatus (image forming method) for forming a color image by an electrophotographic process using a toner that can control color development or non-color development according to color development information by light, to which the present invention is applied. A brief explanation.
The image forming apparatus using the ionography is described in conjunction with the image forming apparatus and the like as appropriate since only the latent image forming process described later is different and the other processes are the same.

FIG. 1 is a schematic configuration diagram showing an example of an image forming apparatus of the present invention. Note that a light shielding means and the like to be described later are omitted. An image forming apparatus shown in FIG. 1 includes a photoconductor (image carrier) 10 used in a normal electrophotographic process, a charging device (charging means) 12, an exposure device (exposure means) 14, a developing device (developing means) 16, a transfer device. An apparatus (transfer means) 18 and a fixing device (fixing means) 22 are provided. Further, in this apparatus, a color information providing device 28 for providing color information to the developed toner image is provided, and the fixing device 22 also serves as a color device (coloring means) for coloring the toner image. Further, a light irradiation device 24 (light irradiation means) for irradiating the recording medium 26 with light for fixing the color development of the toner is provided on the downstream side of the fixing device 22. Reference numeral 20 denotes a cleaner.
Hereinafter, the configuration of the image forming apparatus of the present invention will be described along each step in image formation.

<Latent image forming process>
When the image carrier as shown in FIG. 1 is the photoreceptor 10, the latent image forming means includes a charging device 12 for charging the surface of the photoreceptor and an electrostatic latent image on the surface of the photoreceptor by exposure. And an exposure device 14 to be formed.

First, the entire surface of the photoreceptor 10 is charged by the charging device 12.
As the photoreceptor 10, any known one can be used. For example, an inorganic photosensitive layer such as Se or a-Si, or a single or multilayer organic photosensitive layer is formed on a conductive substrate. In the case of a belt-shaped photoreceptor, a transparent resin such as PET or PC can be used as the substrate, and the thickness is determined by design matters such as the diameter and tension of the roll on which the belt-shaped photoreceptor is stretched, and is approximately 10 to 500 μm. Range. Other layer configurations are the same as in the drum.

  In the coloring information providing step described later, when exposure is performed from the back surface of the photoconductor 10 (inside the photoconductor), a transparent photoconductor having the base as a transparent resin or the like can be used. In the case of a transparent photoconductor, a material transparent to exposure light is used as the photoconductor substrate. For example, glass or plastic material is used as the base material and a conductive layer is formed on the outer surface for electrode formation. However, the base material itself may be subjected to a conductive treatment. In addition, when not using a transparent photoconductor, base materials, such as metal cylindrical bodies, such as aluminum normally used, and a nickel seamless belt other than the above-mentioned transparent base | substrate can also be used.

Further, since the exposure for providing color information, which will be described later, is performed with a considerably stronger intensity than the exposure for forming a normal latent image (the amount of light energy used for providing color information is used in a normal electrophotographic process) The exposure amount to the photoconductor (approximately 1000 times the ² mJ / m ² ) is necessary), and the photoconductor 10 may be damaged. For example, the photosensitivity of the charge generation layer of the photoconductor 10 is 1/1000 of the conventional one. If so, there is no problem because it is balanced.

  Further, it is preferable that the surface of the photoconductor 10 has a function of preventing deterioration of the photoconductor 10 due to exposure for providing color information. Specifically, a surface layer that transmits only the exposure light for forming a latent image and reflects the exposure light for providing color information (but transmits the exposure light for forming a latent image) on the surface of the photosensitive layer. It is effective to provide Examples of the surface layer include a dichroic mirror coat (reflection) and a sharp cut filter (absorption) in which a light absorbing material is dispersed.

On the other hand, when a toner image is formed by ionography, a dielectric is used instead of the photoreceptor 10. The dielectric is formed by providing a dielectric layer on a conductive substrate. Examples of the dielectric include organic materials such as PET, PC, and Teflon, and inorganic materials such as aluminum oxide that has been sealed. Can be used. For the same reason, it is preferable to use a transparent dielectric as the dielectric.
As the transparent dielectric, a transparent dielectric layer, for example, a transparent plastic such as PET or PC can be used instead of the photosensitive layer in the transparent photoreceptor.

  A known charging means can be used for charging the photoreceptor 10. In the case of the contact method, a roll, a brush, a magnetic brush, a blade, or the like can be used. In the case of non-contact, a corotron, a scorotron, or the like can be used. The charging means is not limited to these.

  Among these, a contact-type charger is preferably used because of its excellent charge compensation capability. In the contact charging method, the surface of the photosensitive member is charged by applying a voltage to a conductive member brought into contact with the surface of the photosensitive member. The shape of the conductive member may be any of a brush shape, a blade shape, a pin electrode shape, a roll shape, and the like, but a roll-like member is particularly preferable. Usually, a roll-shaped member is comprised from the resistance layer, the elastic layer which supports them, and a core material from the outside. Furthermore, a protective layer can be provided outside the resistance layer as necessary.

As a method of charging the photosensitive member 10 using these conductive members, a voltage is applied to the conductive member, and the applied voltage is preferably a DC voltage or a DC voltage superimposed with an AC voltage. As the voltage range, the DC voltage is preferably positive or negative 50 to 2000 V, more preferably 100 to 1500 V, and even more preferably 100 to 400 V, depending on the required photosensitive member charging potential. When the AC voltage is superimposed, the peak-to-peak voltage (Vpp) is 400 to 1800 V, preferably 800 to 1600 V, the frequency of the AC voltage is 50 to 20000 Hz, preferably 100 to 5000 Hz, and sine waves, square waves, and triangular waves are generated. Either can be used.
The charging potential is preferably set in the range of 100 to 1000 V in terms of the absolute value of the potential.

  A known exposure device 14 can be used for forming the electrostatic latent image. As the exposure device 14, for example, a laser scanning system, an LED image bar system, analog exposure means, an ion flow control head, or the like can be used, and the surface of the photoconductor 10 is exposed as indicated by an arrow A in FIG. It is possible. In addition to this, new exposure means developed in the future can be used as long as the effects of the present invention are achieved.

  The wavelength of the light source is in the spectral sensitivity region of the photoconductor 10. Until now, the near-infrared having an oscillation wavelength near 780 nm as the wavelength of the semiconductor laser has been mainstream, but an oscillation wavelength laser in the 600 nm range and a laser having an oscillation wavelength near 400 to 450 nm can be used as a blue laser. . A surface-emitting laser light source capable of multi-beam output is also effective for color image formation.

  Exposure to the photoconductor 10 is performed as a logical sum of the image formation information of the four colors at a position where toner described later is developed in the case of reversal development, and at a position other than developing toner in the case of regular development. The exposure spot diameter is preferably in the range of 40 to 80 μm so that the resolution is in the range of 600 to 1200 dpi. As the exposure amount, it is preferable that the post-exposure potential is in the range of about 5 to 30% of the charging potential. However, when changing the toner development amount according to the gradation of the image, the exposure position The exposure amount may be changed according to the development amount every time.

On the other hand, in the case of the ionography, a latent image is formed on the image carrier by an ion writing head. As an ion writing head, for example, an ion flow On / Off control using an image signal (Japanese Patent Laid-Open No. 4-122654), or an ion flow itself is controlled On / Off (Japanese Patent Laid-Open No. 6-99610). Publication) can be used.
In this method, not only a dielectric but also a photosensitive member can be used as the image carrier.

<Development process>
A known developing device (developing means) 16 can be used for developing the electrostatic latent image. As a development method, a two-component development method composed of fine particles and toner for carrying a toner called a carrier, or a one-component development method composed of only a toner, and further improvement of other characteristics in these development methods Any developing method in which other constituents may be added can be used.

  Further, depending on the developing method, any one of the developer that develops in contact or non-contact with the photoreceptor 10 or a combination thereof can be used. Furthermore, a hybrid development method combining the one-component development method and the two-component development method can also be used. In addition to this, a new developing means developed in the future can be used as long as the effect of the present invention is achieved.

As the toner contained in the developer, for example, a color developing portion (Y color forming portion) capable of developing color to Y color, a color developing portion capable of developing color to M color (M color forming portion), and a color developing portion capable of developing color to C color ( (C coloring portion) may be included in one toner particle, or the Y coloring portion, M coloring portion, and C coloring portion may be included separately for each toner.
The toner development amount (the amount of toner attached to the photoreceptor) varies depending on the image to be formed, but it is preferably in the range of 3.5 to 8.0 g / m ² in a solid image, and is preferably 4.0 to 6 More preferably, it is in the range of 0.0 g / m ² .

  In addition, in the formed toner image T, the light for providing coloring information to be described later must spread over the entire irradiated portion, and therefore it is preferable to keep the toner layer thickness below a certain level. Specifically, for example, in a solid image, the toner layer is preferably 3 layers or less, more preferably 2 layers or less. The toner layer thickness is a value obtained by measuring the thickness of the toner layer actually formed on the surface of the photoconductor 10 and dividing this by the number average particle diameter of the toner.

<Coloring information application process>
Next, as shown in FIG. 1, color information by light as indicated by an arrow B is applied to the toner image T thus obtained by a color information applying device 28 as shown in FIG.
The coloring information providing device 28 may be anything as long as the toner particles to be colored at that time can emit light having a wavelength for developing a specific color with a predetermined resolution and intensity. For example, an LED image bar, a laser ROS, or the like can be used. In addition, it is preferable that the irradiation spot diameter of the light irradiated to the toner image T is adjusted so that it may become the range of 10-300 micrometers so that the resolution of the image formed may be the range of 100-2400 dpi. More preferably, it is in the range of 200 μm.

The wavelength of light used to maintain the colored or non-colored state is determined by the material design of the toner used. For example, when using a toner that develops color when irradiated with light of a specific wavelength (photochromic toner), yellow 405 nm light (referred to as λ _A light) for color development (Y color), 535 nm light (referred to as λ _B light) for cyan (C color) color development for magenta (M color) When irradiating, light of 657 nm (referred to as λ _C light) is irradiated to each desired position for color development.

When the secondary color is developed, the light is combined. When the red (R color) is developed, λ _A light and λ _B light are used. When the green (G color) is developed, λ _A light and When the λ _C light is colored blue (B color), the λ _B light and the λ _C light are respectively applied to the desired positions for color development. Further, when the black color (K color), which is the tertiary color, is developed, the λ _A light, λ _B light, and λ _C light are applied to the desired positions for color development.

On the other hand, in the case of a toner that maintains a non-colored state by irradiation with light of a specific wavelength (light non-colorable type toner), for example, to prevent yellow (Y color) from being colored, 405 nm light (λ _A light) , 535 nm light (λ _B light) to prevent magenta (M color) color development, and 657 nm light (λ _C light) color development to prevent cyan (C color) color development. Irradiate each desired position. Accordingly, λ _B light and λ _C light are generated when Y color is generated, λ _A light and λ _C light are generated when M color is generated, and λ _A light and λ _B light are generated when C color is generated. Each of the desired positions for color development is irradiated.

When the secondary color is developed, the light is combined. When the red (R color) is developed, λ _C light is emitted. When the green (G color) is developed, λ _B light is transformed into blue (B When a color is developed, λ _A light is irradiated to each desired position for the color development. Further, when black (K color) which is a tertiary color is developed, exposure is not performed at a desired position where the color is developed.

For the light from the coloring information applying device 28, a known image modulation method such as pulse width modulation, intensity modulation, or a combination of the two described above can be used as necessary. The exposure amount of light is preferably in the range of 0.05~0.8mJ / cm ^2, and more preferably in the range of 0.1~0.6mJ / cm ^2. Particularly with respect to the exposure amount, exposure required amount is correlated with the amount of toner developed, for example, 0.2～0.4MJ the toner developing amount (solid) of about 5.5g / ^{m 2} / ^{m 2} It is preferable to perform exposure within the above range.

Hereinafter, it will be briefly described at what timing and for what position control the exposure for giving the coloring information is performed.
FIG. 2 is a specific circuit block diagram of the print control unit in the image forming apparatus of the present invention. In the figure, the printer controller 36 includes an OR circuit 40, an oscillation circuit 42, a magenta color control circuit 44M, a cyan color control circuit 44C, a yellow color control circuit 44Y, and a black color control circuit 44K. On the other hand, the exposure unit 38 is composed of an optical writing head 32 and a coloring information applying exposure head 34.

  Image data obtained by converting input RGB signals into CMYK values by an interface (I / F) (not shown) is further transmitted from the interface (I / F) to magenta (M), cyan (C), yellow (Y), and black. The pixel data (K) is output to the OR circuit 40. Here, the logical sum circuit 40 calculates the logical sum of CMYK and outputs it to the optical writing head 32.

  That is, logical sum data including all CMYK pixel data is output to the optical writing head 32, and optical writing is performed on the photosensitive member 10 as described above. Therefore, an electrostatic latent image based on logical sum data including all CMYK pixel data is formed on the peripheral surface of the photoreceptor 10.

  The CMYK pixel data is also supplied to the corresponding magenta color control circuit 44M to black color control circuit 44K, and the color information providing exposure head is synchronized with the oscillation signals fm, fc, fy, and fk output from the oscillation circuit 42. 34. That is, color data corresponding to each of magenta (M), cyan (C), yellow (Y), and black (K) is supplied to the color information providing exposure head 34, and the toner image T developed on the photoreceptor 10 is developed. Corresponding to the above, light of a specific wavelength for maintaining a colored or non-colored state is irradiated. Therefore, a photocuring reaction, which will be described later, occurs in the toner that has received the irradiated light, and color development information is given.

For example, color signal fm outputted from the magenta coloring control circuit 44M irradiates the lambda _B light in the color of the toner to the toner in a state capable of color development of magenta (M) color. In addition, the color development signal fc output from the cyan color development control circuit 44C irradiates the color development portion in the toner with the λ _C light, and makes the toner capable of developing cyan (C) color. Further, the same applies to yellow (Y) and black (K), and the color signals fy and fk output from the yellow color control circuit 44Y and the black color control circuit 44K are transmitted to the color development portion in the toner by the λ _A light or Irradiation with λ _A light, λ _B light, and λ _C light enables a yellow (Y) or black (K) color.

In the present invention, as shown in FIG. 3, the color information providing exposure may be performed from the back surface of the photoreceptor 10. In this way, since the exposure means 28 for providing coloring information can be installed inside the image carrier, the entire apparatus can be made more compact.
It will be good.

  As described above, the mechanism for forming a full color image has been described with respect to the color information providing step (means) in the present invention. However, the color information providing step in the present invention is a monochromatic color that produces one of yellow, magenta, and cyan. It may be a color information providing step for forming a color image. In this case, only the light of a specific wavelength corresponding to the desired color development among the yellow, magenta and cyan is emitted from the color development information imparting exposure head 34. Other preferable conditions and the like are the same as those at the time of full-color image formation.

<Transfer process>
The toner to which the color development information is given is then transferred to the recording medium 26 at a time. A known transfer device 18 can be used for transfer. For example, rolls, brushes, blades, and the like can be used for the contact method, and corotron, scorotron, pin corotron, and the like can be used for the non-contact method. Also, transfer by pressure or pressure and heat is possible.

  The transfer bias is preferably in the range of 300 to 1000 V (absolute value), and alternating current (Vpp: 400 V to 4 kV, 400 to 3 kHz) may be superimposed.

<Fixing process and coloring process>
The toner image in a state where it can be colored (or maintained in a non-colored state) is colored as described above when the recording medium 26 is heated by the fixing device 22. A known fixing means can be used as the fixing device 22. For example, a roll or a belt can be selected as the heating member and the pressure member, and a halogen lamp, IH, or the like can be used as the heat source. The arrangement can also correspond to various paper paths, for example, a straight path, a rear C path, a front C path, an S path, a side C path, and the like.

  In the present embodiment, the fixing device 22 serves as both a coloring process and a fixing process, but the coloring process may be provided separately from the fixing process. There is no particular limitation on the position where the color developing device for performing the color developing step is arranged.

  As the color development method, various methods can be considered according to the color development mechanism of the toner particles. Therefore, as the color development device (color development means), for example, the color development-related substance is cured in the toner using light of a different wavelength. Alternatively, a light emitting device that emits specific light by a method such as photolysis or a method that restricts the color, or a pressure device that causes a color to be developed or restricted by a method such as destroying colored particles encapsulated by pressurization. , Etc. can be used.

  However, these chemical reactions that cause color development generally have a slow reaction rate due to migration and diffusion, so it is necessary to give sufficient diffusion energy to any of the above methods. It can be said that the method of promoting the reaction is the best. For this reason, it is preferable to use a fixing device 22 that serves as both the color developing step and the fixing step.

<Shading process>
The first aspect of the present invention includes a light shielding step in addition to the above steps. Although this step is included in the configuration of the first aspect of the present invention, it is not included as a normal image forming step. As will be described later, this step is performed in response to a certain signal when an apparatus trouble occurs. It is what is said.
Here, “light shielding” in this step is to shield the developer in the developing unit from light existing in the apparatus, and the light shielding is to shield the developer exposed on the surface of the developer carrying member. And the case where the exposed developer and the developer inside the developing unit are shielded from light. The “light existing in the apparatus” means stray light, outside light, or light from other light sources inside the apparatus.

  The light shielding means in the first aspect of the present invention is not particularly limited as long as it can shield the developing means, specifically, the developer in the developing unit from external light. However, it is preferable that the light shielding means is attached to the developing means from the viewpoint of surely achieving the object as described above and further making the mechanism as simple and compact as possible.

(First embodiment)
FIG. 4 is a schematic diagram showing a state in which a developing unit provided with an openable / closable shutter that shields the opening as the light shielding means attached to the developing means faces the photosensitive member. A state in which the shutter is opened and (B) show a state in which the shutter is closed.
In FIG. 4, the developer unit 70 is filled with toner 68, and a developer layer is formed on the surface of the developing roll by the rotation of the developing roll (developer carrying member) 64. In this state, the developer layer is brought close to the photoconductor (image carrier) 62, whereby a toner image is formed on the surface of the photoconductor.

  The developing unit 70 is provided with a shutter 66 that can shield light by closing the opening 65. The shutter 66 is configured to be rotatable. When the developing unit 70 is not set in the image forming apparatus so as to be able to perform development, the shutter 66 opens the opening 65 as shown in FIG. The toner 68 in the developing unit 70 is shielded from light.

  In this case, it is preferable to move the developing unit 70 to the side away from the photosensitive member 62 (the right side in the drawing) before the opening 65 is closed by the shutter 66 or during the closing operation. When the shutter 66 is closed, the shutter 66 enters the gap between the opening 65 and the photosensitive member 62 as shown in FIG. 4B. Therefore, by moving the developing unit 70 in this way, The opening 65 can be closed without the shutter 66 contacting the photoconductor 62 and being damaged.

  When the developing unit 70 is mounted on the image forming apparatus and set at a position facing the photoconductor 62 so that development can be performed, the shutter 66 rotates in conjunction with this operation, and FIG. As shown, the opening 65 is in an open state. Naturally, in this state, not only the surface of the developing roll 64 but also the developer inside the developing device unit 70 is opened, so that the inside of the apparatus is completely shielded from light so as not to be exposed to light.

  In this case, it is preferable to move the developing unit 70 to the side close to the photosensitive member 62 (left side in the drawing) after opening the shutter 66 of the opening 65 or during the opening operation. In the state shown in FIG. 4B, the developing unit 70 is too far away from the photosensitive member 62, and therefore good development cannot be performed unless it is moved to an appropriate gap.

Next, the timing for performing the light shielding operation from the state in which the shutter 66 in FIG. 4A is opened to the state in which the shutter 66 in FIG. 4B is closed will be described.
In the present invention, the light shielding operation is preferably performed by an external instruction signal or a signal based on an operation for maintaining the inside of the apparatus.

  First, the signal from the outside means a light shielding operation instruction signal that is artificially transmitted from an operation panel or the like before performing an operation for solving the trouble when a trouble such as a paper jam occurs. Based on this signal, the shutter 66 shown in FIG. 4A changes from the opened state to the closed state shown in FIG. 4B. After confirming this light-shielding operation completion signal, the panel cover of the apparatus is opened. Maintenance will be performed.

  Further, the signal based on the operation for maintaining the inside of the apparatus is not a signal that is artificially transmitted as described above, but a signal that is automatically transmitted in conjunction with an operation performed for maintenance. . Therefore, in this case, the light-shielding operation is automatically performed without any particular attention by the same operation as that in the case of performing the conventional normal maintenance.

Examples of the operation for maintenance include the following cases.
For example, the developing unit 70 is configured to be separated from the photosensitive member 62 in conjunction with the opening operation of the door or the panel cover of the image forming apparatus main body, and the shutter 66 is performed during or after the separating operation. Is shielded from light so as to cover the opening 65. When external light is incident on the inside of the apparatus, that is, when the door or panel cover of the apparatus is opened, the shutter 66 covers the opening 65 to prevent the external light from being applied to the toner, resulting in poor toner color development. Can be prevented.

  Similarly, in the present invention, the shutter 66 is operated in conjunction with an operation that may cause light to enter the apparatus, such as an operation for exchanging consumables, an operation for removing a paper jam, or an operation for replacing parts inside the apparatus. It is preferable that the opening 65 be closed. With this configuration, the toner 68 in the developing unit 70 can be reliably shielded from light.

  When each operation is completed, the developing unit 70 needs to be set in a state where development is possible again, and the shutter 66 moves to a position where the opening 65 is opened. At this time, as shown in FIG. 4A, after the shutter 66 opens the opening 65 or during the opening operation, the developing unit 70 is moved to the side closer to the photosensitive member 62. The operation timing is appropriately adjusted so that 66 does not damage the surface of the photoconductor 62.

(Second Embodiment)
Next, the aspect which provided the other light-shielding means in 1st this invention is demonstrated. In the present embodiment, in order to avoid light exposure due to maintenance operations or the like, the developer layer on the surface of the developer carrying member is removed in advance and shielded from light.

  FIG. 5 is a schematic enlarged view of the developing unit for explaining a mechanism for peeling off the developer on the surface of the developer carrying member. In the figure, a developing roller (developer carrier) 84 having a developer layer 86A formed on the surface thereof, in particular, a developer 86A containing toner on the surface of the developing roller facing the photosensitive member 82 is removed from the surface of the developing roller. It is comprised so that it may peel. Specifically, a scraper 88 that is movably provided in the developing device unit 80 is provided on the upstream side of the developing position of the developing roll 84 in the rotation direction. Usually, the scraper 88 is not in contact with the developing roll 84. First, the developer 86 is carried on the developing roll 84 as a developer layer 86A in a preset layer thickness required for development and is used for development.

  At this time, the tip of the scraper 88 moves, for example, in the direction indicated by the arrow E in FIG. Is rotated in the direction of the arrow, at least the developer layer 86A on the surface of the developing roll 84 facing the photoreceptor 82 is peeled off, and unnecessary light exposure can be avoided. In this case, in order to complete the scraper operation, after the scraper 88 contacts the developing roll 84, the developing roll 84 is rotated until at least the developer layer on the surface of the developing roll 84 facing the photoreceptor 82 is peeled off. Need to be continued.

As the scraper 88, it is preferable to use SUS, phosphor bronze or the like.
The timing for performing the light shielding operation by peeling the developer from the surface of the developing roll shown in FIG. 5 is the same as the timing for closing the opening of the developer unit shown in FIG. It is performed by an instruction signal or a signal based on an operation for maintaining the inside of the apparatus. Also, the operation for the maintenance is the same as the above-described operations.

(Third embodiment)
Next, the aspect which provided the further another light-shielding means in 1st this invention is demonstrated. In the present embodiment, in order to avoid light exposure due to maintenance operation or the like, the developer layer on the surface of the developer carrying member is removed in advance and shielded from light. However, the applicable developer is limited to a magnetic developer.

  FIG. 6 is a schematic enlarged view of the developing unit for explaining a mechanism for peeling off the developer on the surface of the developer carrying member. In the drawing, a developer 96 containing toner is a magnetic developer, and a magnetic blade 98 is disposed between the N pole and the S pole of an internal magnetic pole 93 provided in the developing roll 96. In this state, a uniform developer layer 96 </ b> A is formed on the surface of the developing roll 94, and development on the photoconductor 92 becomes possible.

  On the other hand, when the peeling operation of the developer layer 96 </ b> A on the surface of the developing roll 94 is performed, the N pole or S pole of the internal magnetic pole 93 is moved to a position P (directly below the magnetic blade 98 in the figure) facing the magnetic blade 98. As a result, a tight magnetic shielding region is formed between the N pole or S pole and the magnetic blade 98, and the developer 96 is prevented from flowing downstream in the rotation direction. The developer layer 96A is peeled off, and unnecessary light exposure can be avoided. In this case, after the N pole or S pole of the internal magnetic pole 93 has moved to the position P facing the magnetic blade 98 in order to complete the peeling operation, at least the developer layer on the surface of the developing roll 94 facing the photoreceptor 92. The rotation of the developing roll 94 needs to be continued until 96A is peeled off.

  The timing for performing the light shielding operation by the developer peeling from the surface of the developing roll shown in FIG. 6 is the same as the timing for closing the opening of the developer unit shown in FIG. This is performed by a signal or a signal based on an operation for maintaining the inside of the apparatus. Also, the operation for the maintenance is the same as the above-described operations.

(Fourth embodiment)
Next, the aspect which provided the further another light-shielding means in 1st this invention is demonstrated. Also in this embodiment, in order to avoid light exposure due to a maintenance operation or the like, only the toner in the developer layer on the surface of the developer carrying member is previously removed to shield the light. However, when the developer consists only of non-magnetic toner, the entire developer layer is removed.

  FIG. 7 is a schematic enlarged view of the developing unit for explaining a mechanism for removing the toner in the developer on the surface of the developer carrying member. In the figure, the developer 106 containing toner passes through the layer forming means 107 pressed against the developing roll 104, and a uniform developer layer 106 A is formed on the surface of the developing roll 104. Is possible.

  On the other hand, when the toner is removed from the developer layer 106A on the surface of the developing roll 104, the electrode 108 is brought close to the surface on the downstream side of the layer forming unit 107 of the developing roll 104, and at the same time, a voltage having a polarity opposite to that of the toner (Not shown) is applied to the electrode 108. As a result, the toner is developed on the electrode 108 from the developer layer 106A after the layer formation, and at least the toner on the surface of the developing roll 104 facing the photoreceptor 102 is consumed, so that subsequent exposure to external light can be avoided. . In this case, in order to complete the toner consumption operation, after the voltage is applied to the electrode 108, the rotation of the developing roll 104 is continued until at least the toner on the surface of the developing roll 104 facing the photoreceptor 102 is consumed. It is necessary to

As the electrode 108, a known electrode material is preferably used, and the applied voltage is preferably in the range of 0 to 2 kV in absolute value.
The timing for performing the light shielding operation by removing the toner from the developer layer on the surface of the developing roll shown in FIG. 7 is the same as the timing for closing the opening of the developer unit shown in FIG. This is performed by an instruction signal from the outside or a signal based on an operation for maintaining the inside of the apparatus. Also, the operation for the maintenance is the same as the above-described operations.

(Fifth embodiment)
Furthermore, the aspect which provided the other light-shielding means in 1st this invention is demonstrated.
As a method for shielding the developer in the developing unit from the light inside the apparatus, it is effective to provide a mechanism for retracting at least the developing unit into a light-shielding section provided in advance as necessary, such as maintenance and recovery operations. Here, “at least retreating the developing means” includes retreating not only the developing means but also other means into the light shielding section.

FIG. 8 is a schematic view showing the mechanism.
In the drawing, the developing unit 72 as developing means is movable in the direction of arrow F (left and right in the figure), and a shutter 74 is provided at the retreating port behind the developing unit 72 (right side in the figure). A box-shaped light shielding section 73 is provided. Other configurations are the same as those of the image forming apparatus shown in FIG.

  The developer unit 72 that accommodates the toner provided facing the photoconductor 10 is retracted to a light shielding section 73 provided in a direction opposite to the side facing the photoconductor 10 as necessary. The retreat opening of the light-shielding section 73 facing the door is blocked by the shutter 74. As a result, the toner in the developing unit can be safely processed without being exposed to external light or the like. In this case, depending on the configuration of the apparatus, the image forming unit in which other functional elements such as the photoconductor 10, the cleaning device, and the charging device are integrated together with the developing unit 72 may be retracted to the light shielding section 73.

The timing of performing the light shielding operation by retreating to the light shielding section 73 shown in FIG. 8 is the same as the timing of the operation of closing the opening of the developing unit unit shown in FIG. Alternatively, it is performed by a signal based on an operation for maintaining the inside of the apparatus. Also, the operation for the maintenance is the same as the above-described operations.
As mentioned above, although the 5th aspect was mentioned and demonstrated about the light-shielding process in 1st this invention, this invention is not restrict | limited to these.

<Developer removal process>
The second aspect of the present invention includes a developer removing step in addition to the steps for performing the basic image formation. Although this step is included in the configuration of the second aspect of the present invention, it is not included as a normal image forming step. As will be described later, this step is performed in response to a certain signal when an apparatus trouble occurs. It is what is said.
Here, the removal of the developer in this step means removing at least unnecessary toner out of the system from the developer on the surface of the developer carrying member that has been exposed to light, and this includes the unnecessary toner. The case where the whole developer is removed is included.

  The developer removal in the second aspect of the present invention is not particularly limited as long as at least unnecessary toner (toner exposed to light) can be removed from the developer exposed to light on the surface of the developer carrying member. Specifically, when the developer on the surface of the developer carrying member has been exposed to light due to a trouble in the apparatus, the above-mentioned at least unnecessary operation can be performed by partially changing normal process conditions without moving the developer unit. It is desirable that the toner can be removed.

(First embodiment)
FIG. 9 is a schematic view showing a state in which unnecessary toner on the surface of the developer carrying member exposed to light by the developer removing means is developed on the image carrying member and the toner is removed, and (A) is just after the exposure. (B) shows a state where the light exposure toner is developed.
In a normal development state, as shown in FIG. 9A, a uniform developer layer 68A (only the toner is shown in the figure) is formed on the surface of the developing roll (developer carrier) 64, and the developer Since the developer layer is exposed at the opening of the unit 70, when the panel cover is opened due to an apparatus trouble, external light hits the exposed surface and the toner in the developer layer 68B in that portion is exposed to light.

  Therefore, in order to remove the developer layer 68A containing the light-exposed toner, the developing roller 64 is not rotated, or only the light-exposed portion is slightly moved, and only the photosensitive member 62 is rotated in the direction of arrow C. 9B, only the light exposure toner in the developer layer 68B is developed on the photosensitive member 62, and the light exposure toner is not mixed with the developer 68 in the developing unit as shown in FIG. Can be removed from the surface of the developing roll 64. Then, by collecting the developed toner to a cleaner (not shown) without transferring it, only unnecessary toner exposed to light can be removed out of the system.

  The timing of performing the developer removing operation from the state where the developer of FIG. 9A is exposed to light to the state where the unnecessary toner of FIG. 4B is developed is the same as in the first aspect of the present invention. It is preferable to perform the agent removal operation by an external instruction signal or a signal based on an operation for maintaining the inside of the apparatus. However, in the second aspect of the present invention, any of the above signals is transmitted artificially or in conjunction with the operation end operation after the end of the maintenance operation, for example.

(Second Embodiment)
Next, an embodiment provided with another developer removing means in the second aspect of the present invention will be described. In this embodiment, the toner exposed to light is returned to the developer in the developing unit as it is without being developed and dispersed therein.

  FIG. 10 shows a state where unnecessary toner on the surface of the developer carrying member exposed to light by other developer removing means is developed on the image carrying member and the toner is removed. As shown in FIG. 10A, when the developer layer 68B in the exposed portion of the developing roll 64 is exposed to light, as shown in FIG. 10B, for example, the developing roll is not rotated without rotating the photoreceptor 62. If only 64 is rotated in the direction of arrow D without applying a developing bias, the light exposure toner in the developer layer 68B is dispersed in the developer 68 in the developer unit as shown in the figure, and the developer used for development As a whole, it hardly affects the color reproducibility in the toner image. Therefore, such means is also effective.

The timing of performing the developer removal operation by dispersing the light exposure toner shown in FIG. 10 in the developer in the developing unit is the same as the timing of the operation of developing only the light exposure toner on the photoreceptor shown in FIG. It is preferable that the developer removing operation is performed by an instruction signal from the outside or a signal based on an operation for maintaining the inside of the apparatus.
As mentioned above, although the developer removal process in the second aspect of the present invention has been described by taking two aspects, the present invention is not limited to these.

<Other processes>
In the present invention, it is preferable to include a light irradiation step of irradiating the image obtained through the fixing and coloring steps with light. This makes it possible to decompose or deactivate the reactive substances remaining in the color-development part that has been controlled to be incapable of color development. Can be removed and bleached.
In this embodiment, the light irradiation step is provided after the fixing step. However, in the case of a fixing method that does not heat and melt, for example, pressure fixing in which fixing is performed using pressure, the fixing step is performed after the light irradiation step. Can also be done.

  The light irradiation device 24 is not particularly limited as long as the color development of the toner can be prevented from proceeding further, and a known lamp such as a fluorescent lamp, LED, EL, or the like can be used. Further, the wavelength includes three wavelengths in the light for coloring the toner, the illuminance is preferably in the range of 2000 to 200000 lux, and the exposure time is preferably in the range of 0.5 to 60 sec.

  In addition to these, the above-described image forming method may include a known process used in an electrophotographic process performed using a colorant such as a conventional pigment, for example, after transferring a toner image. A cleaning step for cleaning the surface of the image carrier may be included. As the cleaner 20, a known one can be used, and a blade, a brush, or the like can be used. A so-called cleaner-less process in which the cleaner 20 is removed is also applicable.

  In addition, the transfer process includes a first transfer process in which a toner image is transferred from an image carrier to an intermediate transfer body such as an intermediate transfer belt, and the toner image transferred onto the intermediate transfer body is used as a recording medium. An intermediate transfer method including a second transfer step for transferring may be used.

<Toner to be used>
Next, the toner used in the present invention will be described.
As described above, the toner used in the present invention is a toner that is controlled so as to be able to maintain a colored state or a non-colored state by applying coloring information by light. “Maintaining a colored or non-colored state” is also as described above.

  There are various types of toner having the above functions. For example, the toner disclosed in Patent Document 2 is a plurality of microcapsules having a capsule wall whose substance permeability is changed by an external stimulus. Are dispersed and mixed in a toner resin, and one of two kinds of reactive substances (color dye precursors) mixed with each other to cause a color reaction is contained in the microcapsule and the other. (Developer) is contained in the toner resin outside the microcapsule.

This toner uses a photoisomerized substance that increases the substance permeability when irradiated with light of a specific wavelength as the capsule wall, and when applying light irradiation or ultrasonic waves using this cis-trans transition, Two kinds of reactive substances existing inside and outside the capsule react to develop color.
Therefore, in such a toner, the transition to the color development state is a cis-trans transition, and it is necessary to irradiate the microcapsule itself with color development information imparting light. The impact is small. However, the low color recording sensitivity means that the microcapsules cannot receive light sufficiently, the color development efficiency is low, and a high-definition color image cannot be obtained.

For this reason, in the present invention, a photocurable composition comprising a first component and a second component that exist in a state of being separated from each other and that develop color when reacted with each other, and any one of the first component and the second component And the photocurable composition is maintained in a cured or uncured state by the application of color development information by light, and the reaction for color development is controlled (hereinafter referred to as “F toner”). In some cases).
In this case, in the F toner, since the reaction for shifting to the color developing state occurs in a portion other than the microcapsule wall, the color recording sensitivity is high, and the influence of the light exposure in the present invention is great. The present invention is suitable for use in
The color development mechanism and simple configuration of the toner will be described below.

As will be described later, the F toner can be colored in one specific color (or can maintain a non-colored state) when color development information by light called a color development portion is imparted to the binder resin. ) It has one or more continuous areas.
FIG. 11 is a schematic view showing an example of the color developing portion in the F toner. FIG. 11A is a cross-sectional view of one color developing portion, and FIG. 11B is an enlarged view of the color developing portion.

  As shown in FIG. 11 (A), the color developing section 60 is composed of color-forming microcapsules 50 containing color formers of the respective colors and a composition 58 surrounding the color-forming microcapsules 50. As shown in FIG. The product 58 includes a developer monomer (second component) 54 and a photopolymerization initiator having a polymerizable functional group that develops color by approaching or contacting with the color former (first component) 52 contained in the microcapsule 50. 56.

  As the color former 52 encapsulated in the color developable microcapsules 50 in the color development portion 60 constituting the toner particles, a triaryl leuco compound having excellent color hue is suitable. As the developer monomer 54 for coloring the leuco compound (electron donating property), an electron accepting compound is preferable. In particular, phenolic compounds are common, and can be appropriately selected from color developers used for heat-sensitive and pressure-sensitive paper. The color former develops color by an acid-base reaction between the electron donating color former 52 and the electron acceptor developer monomer 54.

As the photopolymerization initiator 56, a spectral sensitizing dye that generates a polymerizable radical that is exposed to visible light and serves as a trigger for polymerizing the developer monomer 54 is used. For example, a reaction accelerator of the photopolymerization initiator 56 is used so that the color-developing monomer 54 can cause a sufficient polymerization reaction for the three primary color exposures such as R color, G color, and B color. For example, by using an ion complex composed of a spectral sensitizing dye (cation) that absorbs exposure light and a boron compound (anion), the spectral sensitizing dye is photoexcited by exposure and electron transfer to the boron compound causes a polymerizable radical to be generated. To initiate polymerization.
By combining these materials, a color recording sensitivity of about 0.1 to 0.2 mJ / cm ² can be obtained as the photosensitive color developing portion 60.

  Depending on the presence / absence of light irradiation for color forming information on the color forming part 60 having the above-described configuration, some of the color forming part 60 has a polymer developer compound that has been polymerized and a developer monomer 54 that has not been polymerized. . In the color development unit 60 having the developer monomer 54 that has not been polymerized by a subsequent color development device such as heating, the color developer monomer 54 migrates due to heat or the like, and migrates through the pores of the partition walls of the color developer microcapsule 50. Passes through and diffuses into the color former microcapsules. The developer monomer 54 and the color former 52 diffused in the microcapsule 50 are, as described above, the color former 52 is basic and the developer monomer 54 is acidic, so that the color developer 52 is acid-base. The reaction will cause color development.

  On the other hand, the developer compound that has undergone the polymerization reaction cannot pass through the pores of the partition walls of the microcapsule 50 due to the bulk due to the polymerization in the subsequent color development step by heating or the like, and the color former 52 in the color development microcapsule. Color cannot be developed because it cannot react. Therefore, the chromogenic microcapsule 50 remains colorless. That is, the color developing portion 60 irradiated with the specific wavelength light is colored and exists.

  After color development, the entire surface is exposed again with a white light source at an appropriate stage to polymerize all remaining undeveloped color developing monomer 54 to achieve stable image fixing, and residual spectral sensitizing dye. The ground color is erased by disassembling. Note that the spectral sensitizing dye of the photopolymerization initiator 56 corresponding to the visible light region remains as a ground color until the end. Color phenomenon can be used. In other words, a polymerizable radical is generated by electron transfer from a photoexcited spectral sensitizing dye to a boron compound. This radical causes polymerization of the monomer, while reacting with the excited dye radical to cause color separation of the dye. As a result, the pigment can be decolored.

In the F toner, the color developing portions 60 (for example, Y color, M color, and C color) that perform such different color development are used as color developing agents other than the color developing agent 72 intended by each developer monomer 54. And can be used as one microcapsule in a state where they do not interfere with each other (in a state where they are isolated from each other). In this F toner, the space other than the microcapsules containing the electron-donating color former is filled with the electron-accepting developer and the photocurable composition, and the color-developing portion constituted thereby receives the light. The light receiving efficiency of the toner particles is overwhelmingly higher than that of the toner disclosed in Patent Document 2. Therefore, it is possible to obtain stable color development efficiency for exposure with a wide incident angle range as compared with other toners.
In addition, as described above, the coloring information imparting mechanism is not a reversible reaction, and as a result, there is no time restriction until color development by heating. As a result, printing up to a low speed range is possible, that is, it is compatible with a wide speed range. In addition, there is also a merit that the degree of freedom is high with respect to the arrangement place of the fixing device or the like where coloring is performed by heating.

The configuration of the F toner will be further described in detail.
The F toner includes a first component and a second component that exist in a state of being separated from each other as colorable substances (coloring substances) and that develop colors when they react with each other. As described above, color development is facilitated by color development utilizing the reaction of two types of reactive components. The first component and the second component may be pre-colored in a state before color development, but are particularly preferably substantially colorless substances.

In order to facilitate the color development control, two types of reactive components that develop color when reacting with each other are used as the color developing materials. However, these reactive components do not diffuse the substance even when the color development information by light is not given. If they exist in the same easy matrix, spontaneous color development may progress during storage or manufacture of the toner.
For this reason, it is necessary that the reactive component be contained in different matrices (separated from each other) that are difficult to diffuse into each other region unless coloring information is given. is there.

  Thus, in order to inhibit the material diffusion in the state where the color development information by light is not given and prevent spontaneous color development at the time of storage or production of the toner, the first component of the two types of reactive components is Contained in the first matrix, the second component is contained outside the first matrix (second matrix), and between the first matrix and the second matrix, there is diffusion of the substance between the two matrices. When an external stimulus such as heat is applied, a partition wall having a function that enables diffusion of substances between both matrices according to the kind, strength, and combination of the stimulus is provided. Is preferred.

In order to arrange two types of reactive components in the toner using such a partition wall, it is preferable to use microcapsules.
In this case, the F toner preferably includes, for example, the first component of the two types of reactive components inside the microcapsule and the second component outside the microcapsule. In this case, the inside of the microcapsule corresponds to the first matrix and the outside of the microcapsule corresponds to the second matrix.

  This microcapsule has a core part and an outer shell covering the core part, and inhibits diffusion of substances inside and outside the microcapsule and external stimulus as long as external stimulus such as heat is not given. In this case, there is no particular limitation as long as it has a function that enables diffusion of substances inside and outside the microcapsule according to the type, strength, and combination of the stimulus. The core part contains at least one of the reactive components.

In addition, the microcapsule may be capable of diffusing substances inside and outside the microcapsule by applying light irradiation or a stimulus such as pressure, but the substance can be diffused inside and outside the microcapsule by heat treatment (outer shell substance). Particularly preferred are thermoresponsive microcapsules (which increase permeability).
In addition, the substance diffusion inside and outside the microcapsule when a stimulus is applied, from the viewpoint of suppressing a decrease in color density during image formation or suppressing a change in color balance of an image left in a high temperature environment, It is preferably irreversible. Therefore, the outer shell of the microcapsule irreversibly increases its substance permeability due to softening, decomposition, dissolution (compatibility with surrounding members), deformation, etc. by applying heat treatment, light irradiation and other stimuli. It is preferable to have the function of

Next, a preferable configuration when the F toner includes microcapsules will be described.
Such a toner preferably includes a first component and a second component that develop color when they react with each other, a microcapsule, and a photocurable composition in which the second component is dispersed. Examples of the toner include the following three modes.

That is, the F toner includes a first component and a second component that develop color when they react with each other, a photocurable composition, and microcapsules dispersed in the photocurable composition, and the first component is A mode (first mode) in which the second component is contained in the microcapsule and contained in the photocurable composition, a first component and a second component that develop color when reacted with each other, and a photocurable composition A mode in which the first component is included outside the microcapsule and the second component is included in the photocurable composition (second mode), or the first component that develops color when reacted with each other And a second component, one microcapsule containing the first component, and another microcapsule containing a photocurable composition in which the second component is dispersed (third embodiment). It is preferable.
Among these three modes, the first mode is particularly preferable from the viewpoints of stability before giving color development information by light, control of color development, and the like. In the following description of the toner, the toner will be described in more detail on the premise of the toner of the first aspect. However, the configuration, material, manufacturing method, etc. of the toner of the first aspect described below are the same as those of the second aspect. Of course, the toner of the third aspect and the third aspect can also be used / reused.

In addition, it is particularly preferable that the F toner using a combination of the above-described thermoresponsive microcapsule and the photocurable composition is one of the following two types.
(1) Even if the photocurable composition is heat-treated in an uncured state, the material diffusion of the second component contained in the uncured photocurable composition is suppressed, and light is emitted by irradiation with the color forming information providing light. When the heat treatment is performed after the curable composition is cured, a toner of a type that promotes material diffusion of the second component contained in the cured photocurable composition (hereinafter, referred to as “photochromic toner”). is there).
(2) When the photocurable composition is heat-treated in an uncured state (a state where the second component is not polymerized), the material diffusion of the second component contained in the uncured photocurable composition is promoted. When the photocurable composition is cured by irradiation with the color forming information imparting light (after the second component is polymerized), the material diffusion of the second component contained in the cured photocurable composition is caused. The type of toner to be suppressed (hereinafter sometimes referred to as “light non-color developing toner”).

The main difference between the photochromic toner and the non-photochromic toner is in the material constituting the photocurable composition. In the photochromic toner, the photocurable toner has no photopolymerizability. ) Whereas the second component and the photopolymerizable compound are at least included, the photo-non-colorable toner includes at least the second component having a photopolymerizable group in the molecule in the photocurable composition. .
The photocurable composition used in the photochromic toner and the non-photochromic toner preferably contains a photopolymerization initiator, and various other materials are contained as necessary. May be.

  As the photopolymerizable compound and the second component used in the photochromic toner, the interaction between the photocurable composition and the second component in the photocurable composition works in an uncured state. In the photocurable composition, the substance diffusion is suppressed, and the interaction between the two decreases in the state after curing of the photocurable composition (polymerization of the photopolymerizable compound) by irradiation with the color forming information imparting light. A material that facilitates diffusion of the second component is used.

Therefore, in the photochromic toner, before the heat treatment (coloring step), the coloration information imparting light having a wavelength for curing the photocurable composition is irradiated in advance, so that the first color contained in the photocurable composition. The two-component material diffusion becomes easy. Therefore, when the heat treatment is performed, a reaction (coloring reaction) between the first component in the microcapsule and the second component in the photocurable composition occurs due to dissolution of the outer shell of the microcapsule or the like.
On the contrary, the second component is trapped in the photopolymerizable compound even if it is heat-treated without irradiating the color-forming information imparting light having a wavelength for curing the photocurable composition, and comes into contact with the first component in the microcapsule. The reaction between the first component and the second component (coloring reaction) does not occur.

  As described above, in the photochromic toner, the first component and the second component are applied by combining the presence / absence of irradiation with color forming information providing light having a wavelength for curing the photocurable composition and the heat treatment. Can control the color development of the toner.

Further, in the non-photochromic toner, since the second component itself has photopolymerization property, even when irradiated with the color forming information imparting light, the wavelength of this light is not the wavelength that cures the photocurable composition, Since the second component contained in the photocurable composition can be easily diffused, if the heat treatment is performed in this state, the first component in the microcapsule and the photocurable composition are dissolved by dissolution of the outer shell of the microcapsule. Reaction (coloring reaction) with the second component in the composition occurs.
On the contrary, when the coloring information imparting light having a wavelength for curing the photocurable composition is irradiated before the heat treatment, the second components contained in the photocurable composition are polymerized with each other. The material diffusion of the second component contained in the composition becomes difficult. Therefore, the second component cannot be brought into contact with the first component in the microcapsule even when the heat treatment is performed, and the reaction (coloring reaction) between the first component and the second component does not occur.

  As described above, in the non-photochromic toner, the first component and the second component can be applied by combining the heat treatment with the presence / absence of irradiation with color forming information providing light having a wavelength for curing the photocurable composition. Since the reaction (coloring reaction) with the components can be controlled, the color development of the toner can be controlled.

Next, a preferable structure of the F toner will be described in more detail when the toner includes the photocurable composition and microcapsules dispersed in the photocurable composition.
In this case, the toner may have only one color developing portion including a photocurable composition and microcapsules dispersed in the photocurable composition, but preferably has two or more. Here, the “coloring part” means a continuous region that can develop a specific color when an external stimulus is applied as described above.
When the toner includes two or more coloring portions, only one type of coloring portion that can develop the same color may be included in the toner, but two or more types of coloring that can develop colors different from each other may be included. It is particularly preferable that the part is contained in the toner. This is because the color that can be developed by one toner particle is limited to only one type in the former case, but can be two or more in the latter case.

For example, as two or more types of color developing portions capable of developing colors different from each other, a yellow coloring portion capable of developing yellow, a magenta coloring portion capable of developing magenta, and a cyan coloring portion capable of developing cyan Combinations including these are mentioned.
In this case, for example, when only one type of coloring portion is colored by the application of an external stimulus, the toner can be colored in one of yellow, magenta, or cyan, and any two When various types of coloring portions develop color, the colors developed by these two types of coloring portions can be combined, and various colors can be expressed with a single toner particle.

The control of the color to be developed when the toner includes two or more types of coloring portions that can develop colors different from each other depends on the types and combinations of the first component and the second component contained in each type of coloring portion. In addition to making the wavelength different, it can be realized by making the wavelength of light used for curing the photocurable composition contained in each type of color developing portion different.
That is, in this case, since the wavelength of light necessary for curing the photocurable composition contained in the color developing portion differs for each type of color developing portion, a plurality of types having different wavelengths according to the type of color developing portion are used as control stimuli. Coloring information imparting light may be used. In order to make the wavelength of light necessary for curing the photocurable composition contained in the color developing part different, a photopolymerization initiator sensitive to light of a different wavelength is used for each type of color developing part. It is suitable for inclusion in the product.

For example, when the toner includes three types of color-developing parts capable of coloring yellow, magenta, and cyan, the photocurable composition contained in each type of color-forming part has a light wavelength of 405 nm, 532 nm, and If a material that cures in response to any of 657 nm is used, the toner can be colored to a desired color by properly using these three color-developing information-giving lights (lights having specific wavelengths).
The wavelength of the coloring information imparting light can be selected from the visible wavelength, but may be selected from the ultraviolet wavelength.

  The toner used in the present invention may include a base material mainly composed of a binder resin similar to that used in a toner using a colorant such as a conventional pigment. In this case, it is preferable that each of the two or more coloring portions is dispersed as a particulate capsule in the base material (hereinafter, one capsule-like coloring portion may be referred to as a “photosensitive / thermosensitive capsule”). is there). Further, in the base material, a release agent and various additives may be contained in the same manner as a toner using a colorant such as a conventional pigment.

The photosensitive / thermosensitive capsule has a core portion containing a microcapsule or a photocurable composition, and an outer shell covering the core portion, and this outer shell is used in the toner production process and toner storage described later. In the above, there is no particular limitation as long as the microcapsules and the photocurable composition in the photosensitive / thermosensitive capsule can be stably held so as not to leak out of the photosensitive / thermal capsule.
However, in the present invention, in the toner production process described later, the second component passes through the outer shell and flows out to the matrix outside the photosensitive / thermosensitive capsule, or in the photosensitive / thermosensitive capsule capable of developing other colors. In order to prevent the second component from flowing through the outer shell, it is preferable that the second component contains a water-insoluble material such as a binder resin made of a water-insoluble resin or a release material as a main component.

Next, the toner constituent materials used for the F toner and the materials and methods used for adjusting the toner constituent materials will be described in more detail below.
In this case, at least a first component, a second component, a microcapsule containing the first component, and a photocurable composition containing the second component are used for the toner, and a photopolymerization initiator is contained in the photocurable composition. Is particularly preferable, and various auxiliary agents and the like may be included. Further, the first component may be present in a solid state in the microcapsule (core portion), but may be present together with a solvent.

In the light non-color-forming toner, an electron-donating colorless dye or a diazonium salt compound is used as the first component, and an electron-accepting compound having a photopolymerizable group or a photopolymerizable group is used as the second component. A coupler compound or the like is used. In the photochromic toner, an electron-donating colorless dye is used as the first component, and an electron-accepting compound (“electron-accepting developer” or “developer”) is used as the second component. And a polymerizable compound having an ethylenically unsaturated bond is used as the photopolymerizable compound.
In addition to the above-listed materials, various materials similar to those constituting conventional toners using colorants; binder resins, mold release agents, internal additives, external additives, etc., as necessary It can be used as appropriate. Hereinafter, each material etc. are demonstrated in detail.

-1st component and 2nd component-
As the combination of the first component and the second component, the following combinations (a) to (tu) can be preferably mentioned (in the following examples, the former represents the first component and the latter represents the second component, respectively). .

(A) A combination of an electron-donating colorless dye and an electron-accepting compound.
(A) A combination of a diazonium salt compound and a coupling component (hereinafter appropriately referred to as “coupler compound”).
(C) A combination of an organic acid metal salt such as silver behenate or silver stearate and a reducing agent such as protocatechinic acid, spiroindane or hydroquinone.
(D) A combination of a long-chain fatty acid iron salt such as ferric stearate or ferric myristate and a phenol such as tannic acid, gallic acid or ammonium salicylate.
(E) Organic acid heavy metal salts such as nickel, cobalt, lead, copper, iron, mercury and silver salts such as acetic acid, stearic acid and palmitic acid, and alkali metals or alkaline earth such as calcium sulfide, strontium sulfide and potassium sulfide A combination of a metal sulfide or a combination of the organic acid heavy metal salt and an organic chelating agent such as s-diphenylcarbazide or diphenylcarbazone.

(F) A combination of a heavy metal sulfate such as a sulfate such as silver, lead, mercury or sodium and a sulfur compound such as sodium tetrathionate, sodium thiosulfate or thiourea.
(G) A combination of an aliphatic ferric salt such as ferric stearate and an aromatic polyhydroxy compound such as 3,4-hydroxytetraphenylmethane.
(H) A combination of an organic acid metal salt such as silver oxalate or mercury oxalate and an organic polyhydroxy compound such as polyhydroxy alcohol, glycerin or glycol.
(G) A combination of a ferric salt of a fatty acid such as ferric pelargonate or ferric laurate and a thiocesylcarbamide or isothiocecilcarbamide derivative.
(Co) A combination of a lead salt of an organic acid such as lead caproate, lead pelargonate or lead behenate and a thiourea derivative such as ethylenethiourea or N-dodecylthiourea.

(Sa) A combination of a higher aliphatic heavy metal salt such as ferric stearate or copper stearate and zinc dialkyldithiocarbamate.
(B) Those that form an oxazine dye such as a combination of resorcin and a nitroso compound.
(Su) A combination of a formazan compound and a reducing agent and / or a metal salt.
(C) A combination of a protected dye (or leuco dye) precursor and a deprotecting agent.
(So) A combination of an oxidizing color former and an oxidizing agent.
(Ta) A combination of phthalonitriles and diiminoisoindolines. (A combination that produces phthalocyanine.)
(H) A combination of isocyanates and diiminoisoindolines (a combination that produces a colored pigment).
(Iv) A combination of a pigment precursor and an acid or a base (a combination formed by a pigment).

The first component listed above is preferably a substantially colorless electron-donating colorless dye or a diazonium salt compound.
As the electron-donating colorless dye, conventionally known dyes can be used, and any dye that reacts with the second component and develops color can be used. Specifically, phthalide compounds, fluoran compounds, phenothiazine compounds, indolyl phthalide compounds, leucooramine compounds, rhodamine lactam compounds, triphenylmethane compounds, triazene compounds, spiropyran compounds, pyridine Examples thereof include various compounds such as phosphines, pyrazine compounds, and fluorene compounds.

  In the case of the non-photochromic toner, the second component is a substantially colorless compound having a photopolymerizable group and a site that develops color by reacting with the first component in the same molecule. Any compound that has both functions of reacting with the first component such as an electron-accepting compound having a photopolymer or a coupler compound having a photopolymerizable group to develop a color and reacting with light to be cured and cured. be able to.

  The electron-accepting compound having a photopolymerizable group, that is, a compound having an electron-accepting group and a photopolymerizable group in the same molecule has a photopolymerizable group and is one of the first components. Any colorant can be used as long as it reacts with an electron-donating colorless dye and develops color and can be cured by photopolymerization.

  The electron-accepting developer as the second component in the case of the photochromic toner includes phenol derivatives, sulfur-containing phenol derivatives, organic carboxylic acid derivatives (for example, salicylic acid, stearic acid, resorcinic acid, etc.), and Examples thereof include metal salts thereof, sulfonic acid derivatives, urea or thiourea derivatives, acidic clay, bentonite, novolac resins, metal-treated novolac resins, metal complexes, and the like.

  Further, in the photochromic toner, a polymerizable compound having an ethylenically unsaturated bond is used as a photopolymerizable compound, and this is at least in a molecule such as acrylic acid and a salt thereof, an acrylate ester, and an acrylamide. It is a polymerizable compound having one ethylenically unsaturated double bond.

  Next, the photopolymerization initiator will be described. The photopolymerization initiator can generate radicals by irradiating with color forming information imparting light to cause a polymerization reaction in the photocurable composition, and can accelerate the reaction. The photocurable composition is cured by this polymerization reaction.

The photopolymerization initiator can be appropriately selected from known ones, and includes, among others, a spectral sensitizing compound having a maximum absorption wavelength at 300 to 1000 nm and a compound that interacts with the spectral sensitizing compound. It is preferable that
However, if the compound that interacts with the spectral sensitizing compound is a compound having both a dye part and a borate part having a maximum absorption wavelength at 300 to 1000 nm in the structure, the spectral sensitizing dye is used. It does not have to be.

As the compound that interacts with the spectral sensitizing compound, one or more compounds are appropriately selected from known compounds capable of initiating a photopolymerization reaction with the photopolymerizable group in the second component. Can be used.
By making this compound coexist with the above-mentioned spectral sensitizing compound, it is sensitive to the irradiation light in the spectral absorption wavelength region and can generate radicals with high efficiency. Generation of radicals can be controlled using an arbitrary light source in the outer region.

  The “compound interacting with the spectral sensitizing compound” is preferably an organic borate salt compound, a benzoin ether, an S-triazine derivative having a trihalogen-substituted methyl group, an organic peroxide or an azinium salt compound. Borate salt compounds are more preferred. By using this “compound that interacts with the spectral sensitizing compound” in combination with the spectral sensitizing compound, radicals can be generated locally and effectively in the exposed exposed portion, thereby increasing the sensitivity. Can be achieved.

In addition, the photo-curable composition further promotes the polymerization by a transfer agent such as an oxygen scavenger or a chain transfer agent of an active hydrogen donor as an auxiliary agent for the purpose of promoting the polymerization reaction. Other compounds can also be added.
Examples of the oxygen scavenger include phosphine, phosphonate, phosphite, first silver salt, and other compounds that are easily oxidized by oxygen. Specific examples include N-phenylglycine, trimethyl parbituric acid, N, N-dimethyl-2,6-diisopropylaniline, and N, N, N-2,4,6-pentamethylanilic acid. Furthermore, thiols, thioketones, trihalomethyl compounds, lophine dimer compounds, iodonium salts, sulfonium salts, azinium salts, organic peroxides, azides and the like are also useful as polymerization accelerators.

In the F toner, a first component such as an electron-donating colorless dye or a diazonium salt compound is encapsulated in a microcapsule.
A conventionally known method can be used as a microencapsulation method. For example, a method using coacervation of hydrophilic wall forming materials described in U.S. Pat. Nos. 2,800,547 and 2,800,458, U.S. Pat. No. 3,287,154, British Patent No. 990443, Japanese Patent Publication No. 38-19574, No. 42. No. -446, No. 42-771, etc., an interfacial polymerization method described in US Pat. Nos. 3,418,250 and 3,660,304, and an isocyanate polyol wall material described in US Pat. No. 3,796,669 are used. A method using an isocyanate wall material described in U.S. Pat. No. 3,914,511, a method using a urea-formaldehyde system, a urea formaldehyde-resorcinol-based wall forming material described in U.S. Pat. Nos. 4001140, 4087376, and 4089802, US 402 No. 455, a method using a wall forming material such as melamine-formaldehyde resin, hydroxybrovir cellulose, etc., Japanese Patent Publication No. 36-9168, Japanese Patent Application Laid-Open No. 51-9079, in situ method by polymerization of monomers, British Patent No. 952807, Electrolytic dispersion cooling method described in U.S. Pat. No. 965074, US Pat. No. 3,111,407, British Patent No. 930422, Spray drying method, JP-B-7-73069, JP-A-4-101858 Examples include the method described in Kaihei 9-263057.

  The microcapsule wall material that can be used is added inside and / or outside the oil droplets. Examples of the material for the microcapsule wall include polyurethane, polyurea, polyamide, polyester, polycarbonate, urea-formaldehyde resin, melamine resin, polystyrene, styrene methacrylate copolymer, styrene-acrylate copolymer, and the like. Among these, polyurethane, polyurea, polyamide, polyester, and polycarbonate are preferable, and polyurethane and polyurea are more preferable. Two or more kinds of the polymer substances can be used in combination.

  The volume average particle size of the microcapsules is preferably adjusted to be in the range of 0.1 to 3.0 μm, and more preferably adjusted to be in the range of 0.3 to 1.0 μm.

The photosensitive / thermosensitive capsule may contain a binder, and this is the same for a toner having one color developing portion.
Examples of the binder include those similar to the binder used for emulsifying and dispersing the photocurable composition, a water-soluble polymer used for encapsulating the first reactive substance, polystyrene, polyvinyl formal, polyvinyl butyral, poly Acrylic resins such as methyl acrylate, polybutyl acrylate, polymethyl methacrylate, polybutyl methacrylate and copolymers thereof, solvent-soluble polymers such as phenol resin, styrene-butadiene resin, ethyl cellulose, epoxy resin, urethane resin, or these It is also possible to use a polymer latex. Of these, gelatin and polyvinyl alcohol are preferred. Moreover, you may use the binder resin mentioned later as a binder.

  For the F toner, a binder resin used in conventional toners can be used. For example, in a toner having a structure in which photosensitive / thermal capsules are dispersed in a base material, the binder resin can be used as a main component constituting the base material and a material constituting the outer shell of the photosensitive / thermal capsule. It is not limited to this.

  The binder resin is not particularly limited, and a known crystalline or amorphous resin material can be used. In particular, a crystalline polyester resin having sharp melt properties is useful for imparting low-temperature fixability. In addition, as the amorphous polymer (amorphous resin), a known resin material such as a styrene acrylic resin or a polyester resin can be used, but an amorphous polyester resin is particularly preferable.

  In addition, the F toner may contain other components other than those listed above. Other components are not particularly limited and may be appropriately selected depending on the purpose. For example, various known additives used in conventional toners such as release agents, inorganic fine particles, organic fine particles, and charge control agents. Can be mentioned

Next, a method for manufacturing F toner will be briefly described.
The F toner is preferably prepared using a known wet manufacturing method such as an aggregation coalescence method. In particular, a first component and a second component that develop color when they react with each other, a photocurable composition, and a microcapsule dispersed in the photocurable composition, wherein the first component is contained in the microcapsule. The wet manufacturing method is suitable for producing a toner having a structure in which the second component is contained in the photocurable composition.
The microcapsule used for the toner having the above structure is particularly preferably a thermoresponsive microcapsule, but may be a microcapsule that responds to other stimuli such as light.

For the production of toner, a known wet manufacturing method can be used. Among the wet manufacturing methods, the maximum process temperature can be kept low, and the toner having various structures can be easily produced. It is particularly preferable to do this.
Compared to conventional toners mainly composed of pigments and binder resins, toners having the above structure contain more photocurable compositions containing low-molecular components as the main component. Although the strength of the particles obtained by the above method tends to be insufficient, the aggregation and coalescence method does not require a high shearing force, and it is preferable to use the aggregation and coalescence method in this respect as well.

In general, the aggregation and coalescence method includes an aggregation step in which a dispersion of various materials constituting a toner is prepared, and then aggregated particles are formed in a raw material dispersion obtained by mixing two or more types of dispersions. And a coalescing step for fusing the agglomerated particles formed on the surface of the agglomerated particles to form a coating layer between the agglomeration step and the fusing step. The adhesion process (coating layer formation process) to form is implemented.
Also in the production of the F toner, although the types and combinations of the various dispersions used as raw materials are different, the toner can be prepared by appropriately combining the adhering step in addition to the aggregation step and the fusion step.

  For example, in the case of a toner having a photosensitive / thermosensitive capsule dispersion structure in a resin, first, (a1) a microcapsule dispersion in which microcapsules containing a first component are dispersed and a photocurable composition containing a second component A first aggregating step for forming first agglomerated particles in a raw material dispersion containing a photocurable composition dispersion in which a product is dispersed; and (b1) a raw material on which the first agglomerated particles are formed. An adhesion step of adding a first resin particle dispersion in which resin particles are dispersed to the dispersion and attaching the resin particles to the surface of the aggregated particles; and (c1) attaching the resin particles to the surface. One or more types of photosensitive materials that can develop colors different from each other through a first fusion step in which a raw material dispersion containing aggregated particles is heated and fused to obtain first fused particles (photosensitive / heat-sensitive capsules).・ Prepare heat-sensitive capsule dispersion .

Subsequently, (d1) second aggregated particles are formed in a mixed solution obtained by mixing the one or more types of photosensitive / thermosensitive capsule dispersion and the second resin particle dispersion in which the resin particles are dispersed. By passing through a second aggregating step and (e1) a second fusing step of heating the mixed solution containing the second agglomerated particles to obtain second fused particles, a photosensitive / thermosensitive capsule dispersion structure is obtained. A toner having the same can be obtained.
In addition, the kind of photosensitive / heat-sensitive capsule dispersion used in the second aggregation step is preferably two or more. Alternatively, the photosensitive / heat-sensitive capsules obtained through the steps (a1) to (c1) may be used as they are as toner (that is, toner including only one color developing portion).

  In the case of producing a toner including only one color developing portion, a release agent dispersion liquid in which a release agent is dispersed in the raw material dispersion liquid in which the first aggregated particles are formed instead of the above-described adhesion step. And adding a first resin particle dispersion liquid in which resin particles are dispersed in a raw material dispersion liquid after passing through the first adhesion process. A second adhesion step of adding resin particles to the surface of the aggregated particles to which the release agent has been added may be carried out.

The volume average particle size of the F toner that can be used in the present invention is not particularly limited, and can be appropriately adjusted according to the structure of the toner and the type and number of color developing portions contained in the toner.
However, there are about 2 to 4 types of coloring portions that can be developed in different colors contained in the toner (for example, when the toner includes three types of coloring portions that can develop colors of yellow, cyan, and magenta) ), The volume average particle diameter corresponding to each toner structure is preferably within the following range.

  That is, for example, when the toner structure is a photosensitive / thermosensitive capsule (color developing part) dispersion structure in the resin, the volume average particle diameter of the toner is preferably in the range of 5 to 40 μm, more preferably in the range of 10 to 20 μm. . The volume average particle size of the photosensitive / thermosensitive capsule contained in the photosensitive / thermosensitive capsule dispersed structure toner having such a particle size is preferably in the range of 1 to 5 μm, preferably in the range of 1 to 3 μm. It is preferable that

  When the volume average particle diameter of the toner is less than 5 μm, the amount of color developing components contained in the toner decreases, so that color reproducibility may deteriorate and image density may decrease. On the other hand, if the volume average particle size exceeds 40 μm, unevenness on the image surface becomes large, and gloss unevenness on the image surface may occur.

  In addition, the photosensitive / thermosensitive capsule dispersion type toner in which a plurality of photosensitive / thermosensitive capsules are dispersed therein has a particle diameter as compared with a small-diameter toner (volume average particle diameter of about 5 to 10 μm) using a conventional colorant. However, since the resolution of the image is determined not by the particle size of the toner but by the particle size of the photosensitive / heat-sensitive capsule, a higher-definition image can be obtained. In addition, since the powder fluidity is also excellent, sufficient fluidity can be ensured even if the amount of the external additive is small, and the developability and cleaning properties can be improved.

  On the other hand, in the case of a toner having only one color developing portion, it is easier to reduce the diameter as compared with the case described above, and the volume average particle diameter is preferably in the range of 3 to 8 μm, and in the range of 4 to 7 μm. preferable. When the volume average particle size is less than 3 μm, the particle size is too small, so that sufficient powder fluidity may not be obtained or sufficient durability may not be obtained. If the volume average particle size exceeds 8 μm, a high-definition image may not be obtained.

  In the present invention, in addition to the F toner described above, any toner can be used as long as it is controlled so as to maintain a colored or non-colored state by light irradiation (or by no light irradiation). It can be used regardless of the structure, coloring mechanism, etc.

The toner that can be used in the present invention has a volume average particle size distribution index GSDv of 1.30 or less and a ratio (GSDv / GSDp) of the volume average particle size distribution index GSDv to the number average particle size distribution index GSDp is 0. .95 or more is preferable.
More preferably, the volume average particle size distribution index GSDv is 1.25 or less, and the ratio (GSDv / GSDp) of the volume average particle size distribution index GSDv and the number average particle size distribution index GSDp is 0.97 or more. Is more preferable.

  When the volume distribution index GSDv exceeds 1.30, the resolution of the image may decrease, and the ratio of the volume average particle size distribution index GSDv to the number average particle size distribution index GSDp (GSDv / GSDp) is If it is less than 0.95, the toner chargeability may be reduced, the toner may be scattered, fogging, etc. may occur, leading to image defects.

In the present invention, the volume average particle diameter of the toner and the values of the volume average particle size distribution index GSDv and the number average particle size distribution index GSDp are measured and calculated as follows.
First, individual particle size distributions (channels) of the toner particle size distribution measured using a measuring instrument such as Coulter Counter TAII (manufactured by Nikka Machine Co., Ltd.), Multisizer II (manufactured by Nikka Kisha Co., Ltd.) A cumulative distribution is drawn from the small diameter side with respect to the volume and number of the toner particles, and the particle diameter at which accumulation is 16% is defined as volume average particle diameter D16v and number average particle diameter D16p, and the particle diameter at which accumulation is 50%. , Volume average particle diameter D50v and number average particle diameter D50p. Similarly, particle diameters that are 84% cumulative are defined as volume average particle diameter D84v and number average particle diameter D84p. In this case, the volume average particle size distribution index (GSDv) is defined as (D84v / D16v) ^1/2 and the number average particle size index (GSDp) is defined as (D84p / D16p) ^1/2. Can be used to calculate the volume average particle size distribution index (GSDv) and the number average particle size index (GSDp).

  The volume average particle size of the microcapsules or the photosensitive / thermosensitive capsules can be measured using, for example, a laser diffraction particle size distribution measuring device (LA-700, manufactured by Horiba, Ltd.).

The toner of the present invention preferably has a shape factor SF1 represented by the following formula (1) in the range of 110 to 130.
SF1 = (ML ² / A) × (π / 4) × 100 (1)
[In the above formula (1), ML represents the maximum length (μm) of toner, and A represents the projected area (μm ² ) of toner. ]

When the shape factor SF1 is less than 110, the toner tends to remain on the surface of the image carrier in the transfer process during image formation. Therefore, it is necessary to remove the residual toner. The cleaning property at the time of cleaning tends to be impaired, and as a result, an image defect may occur.
On the other hand, when the shape factor SF1 exceeds 130, when the toner is used as a developer, the toner may be destroyed due to collision with a carrier in the developing device. At this time, as a result, the fine powder increases or the release agent component exposed on the toner surface may contaminate the surface of the image bearing member and the like to impair the charging characteristics, and the occurrence of fog caused by the fine powder. May cause problems.

The shape factor SF1 was measured as follows using a Luzex image analyzer (manufactured by Nireco Corporation, FT). First, an optical microscope image of the toner dispersed on the slide glass is taken into a Luzex image analyzer through a video camera, and the maximum length (ML) and projected area (A) of 50 or more toners are measured. (ML ² / A) × (π / 4) × 100 was calculated, and a value obtained by averaging the values was determined as the shape factor SF1.

<Developer>
The toner used in the present invention may be used as it is as a one-component developer, but in the present invention, it is preferably used as a toner in a two-component developer comprising a carrier and a toner.
Here, from the viewpoint that a color image can be formed with one type of developer, the developer is (1) a color development including the photocurable composition and microcapsules dispersed in the photocurable composition. One type of toner having two or more types of parts, and two or more types of coloring parts contained in the toner can develop colors different from each other, or (2) the photo-curing property Two or more kinds of toners having one coloring part including a composition and microcapsules dispersed in the photocurable composition, and the coloring parts of the two or more kinds of toners are mixed with each other. It is preferable that the developer be of a type that can develop different colors.

  For example, in the former type of developer, the toner includes three types of color developing portions, and the three types of color developing portions include a yellow color developing portion capable of developing a yellow color and a magenta color forming portion capable of developing a magenta color. In the latter type of developer, a yellow color developing toner that can develop a yellow color, and a magenta color that can develop a magenta color. The toner is preferably contained in the developer in a state where the color developing portion and the cyan color developing toner capable of developing a cyan color are mixed.

The carrier that can be used for the two-component developer is preferably formed by coating the surface of the core material with a resin. The core material of the carrier is not particularly defined as long as the above conditions are satisfied, for example, magnetic metals such as iron, steel, nickel, cobalt, alloys of these with manganese, chromium, rare earth, ferrite, magnetite, etc. From the viewpoint of the surface property of the core material and the resistance of the core material, ferrite, particularly an alloy with manganese, lithium, strontium, magnesium or the like is preferable.
Further, the resin for covering the surface of the core material is not particularly limited as long as it can be used as a matrix resin, and can be appropriately selected according to the purpose.

  The mixing ratio (mass ratio) of the toner of the present invention and the carrier in the two-component developer is preferably in the range of toner: carrier = 1: 100 to 30: 100, and about 3: 100 to 20: 100. The range of is more preferable.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated more concretely, this invention is not limited only to a following example.
<Example 1>
(toner)
First, the light non-color-forming F toner in which the light emitting part (photosensitive / heat-sensitive capsule) was dispersed in the binder resin was obtained as follows.

-Preparation of microcapsule dispersion (1)-
In 16.9 parts by mass of ethyl acetate, 8.9 parts of an electron-donating colorless dye (1) capable of developing a yellow color is dissolved, and capsule wall material (trade name: Takenate D-110N, Takeda Pharmaceutical Co., Ltd.) 20 parts by mass and 2 parts by mass of capsule wall material (trade name: Millionate MR200, manufactured by Nippon Polyurethane Industry Co., Ltd.) were added.
The resulting solution was added to a mixed solution of 42 parts by mass of 8% by mass phthalated gelatin, 14 parts by mass of water, and 1.4 parts by mass of a 10% by mass sodium dodecylbenzene sulfonate solution. Emulsified and dispersed at 0 ° C. to obtain an emulsion. Next, 72 parts by mass of a 2.9% tetraethylenepentamine aqueous solution was added to the obtained emulsion and heated to 60 ° C. with stirring. After 2 hours, the electron-donating colorless dye (1) was added to the core. To obtain a microcapsule dispersion (1) having an average particle size of 0.5 μm.
The glass transition temperature of the material constituting the outer shell of the microcapsule contained in this microcapsule dispersion (1) (the material obtained by reacting Takenate D-110N and Millionate MR200 under the same conditions as above). Was 100 ° C.

-Preparation of microcapsule dispersion (2)-
A microcapsule dispersion (2) was obtained in the same manner as in the preparation of the microcapsule dispersion (1) except that the electron-donating colorless dye (1) was changed to the electron-donating colorless dye (2). The average particle size of the microcapsules in this dispersion was 0.5 μm.

-Preparation of microcapsule dispersion (3)-
A microcapsule dispersion (3) was obtained in the same manner as in the preparation of the microcapsule dispersion (1) except that the electron-donating colorless dye (1) was changed to the electron-donating colorless dye (3). The average particle size of the microcapsules in this dispersion was 0.5 μm.
The chemical structural formulas of the electron donating colorless dyes (1) to (3) used for the preparation of the microcapsule dispersion are shown below.

—Preparation of Photocurable Composition Dispersion (1) —
100.0 parts by mass (mixing ratio 50:50) of a mixture of electron-accepting compounds (1) and (2) having a polymerizable group and 0.1 part by mass of a thermal polymerization inhibitor (ALI) were added to isopropyl acetate (to water). Was dissolved at 42 ° C. in 125.0 parts by mass to obtain a mixed solution I.
In this mixed solution I, hexaarylbiimidazole (1) [2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′tetraphenyl-1,2′-biimidazole] 18.0 Part by mass, 0.5 part by mass of a nonionic organic dye, and 6.0 parts by mass of an organic boron compound were added and dissolved at 42 ° C. to obtain a mixed solution II.
The above mixed solution II was added to a mixed solution of 300.1 parts by mass of an 8% by mass gelatin aqueous solution and 17.4 parts by mass of a 10% by mass surfactant (1) aqueous solution, and a homogenizer (manufactured by Nippon Seiki Co., Ltd.). ) For 5 minutes at a rotational speed of 10,000, followed by desolvation treatment at 40 ° C. for 3 hours to obtain a photocurable composition dispersion (1) having a solid content of 30% by mass.
In addition, the electron-accepting compound (1) which has a polymeric group used for preparation of a photocurable composition dispersion liquid (1), the electron-accepting compound (2) which has a polymeric group, and thermal polymerization inhibitor (ALI) Structural formulas of hexaarylbiimidazole (1), surfactant (1), nonionic organic dye, and organoboron compound are shown below.

-Preparation of photocurable composition dispersion (2)-
0.6 parts by mass of the following organic borate compound (I), 0.1 part by mass of the spectral sensitizing dye-based borate compound (I) shown below, and the following auxiliary agent (1) for the purpose of increasing sensitivity: 5 parts by mass of the following electron-accepting compound (3) having a polymerizable group was added to a mixed solution of 1 part by mass and 3 parts by mass of isopropyl acetate (solubility of about 4.3% in water).

The obtained solution was mixed with 13 parts by weight of a 13% by weight aqueous gelatin solution, 0.8 part by weight of the following 2% by weight surfactant (2) aqueous solution, and 0.8 part by weight of the following 2% by weight surfactant (3) aqueous solution. And emulsified with a homogenizer (manufactured by Nippon Seiki Co., Ltd.) for 5 minutes at a rotational speed of 10,000 rotations to obtain a photocurable composition dispersion (2).
In addition, the electron-accepting compound (3), auxiliary agent (1), surfactant (2) and surfactant (3) having a polymerizable group used for the preparation of the photocurable composition dispersion (2). The structural formula is shown below.

-Preparation of photocurable composition dispersion (3)-
In place of the spectral sensitizing dye-based borate compound (I), the photocurable composition dispersion liquid (2) was used except that 0.1 part by mass of the spectral sensitizing dye-based borate compound (II) shown above was used. A photocurable composition dispersion (3) was obtained in the same manner as in the preparation.

-Preparation of resin particle dispersion-
Styrene: 460 parts by mass nbutyl acrylate: 140 parts by mass Acrylic acid: 12 parts by mass Dodecanethiol: 9 parts by mass The above components were mixed and dissolved to prepare a solution. Subsequently, an emulsion (monomer) in which 12 parts by weight of an anionic surfactant (manufactured by Rhodia, Dowfax) was dissolved in 250 parts by weight of ion-exchanged water, and the above solution was added and dispersed and emulsified in a flask. Emulsion A) was prepared.
In addition, 1 part of an anionic surfactant (Dowfax, manufactured by Rhodia Co., Ltd.) was dissolved in 555 parts by mass of ion-exchanged water and charged into a polymerization flask. The polymerization flask was sealed, a reflux tube was installed, and the polymerization flask was heated to 75 ° C. with a water bath while being slowly stirred while injecting nitrogen.

Next, a solution obtained by dissolving 9 parts of ammonium persulfate in 43 parts by mass of ion-exchanged water was added dropwise to the polymerization flask through a metering pump over 20 minutes, and then the monomer emulsion A was also added to the metering pump. Over 200 minutes.
Thereafter, the polymerization flask was kept at 75 ° C. for 3 hours while stirring slowly, to complete the polymerization.
As a result, a resin particle dispersion having a median particle diameter of 210 nm, a glass transition point of 51.5 ° C., a weight average molecular weight of 31,000, and a solid content of 42% by mass was obtained.

-Preparation of photosensitive / thermosensitive capsule dispersion (1)-
-Microcapsule dispersion (1): 150 parts by mass-Photocurable composition dispersion (1): 300 parts by mass-Polyaluminum chloride: 0.20 parts by mass-Ion exchange water: 300 parts by mass The above ingredients are mixed. Nitric acid is added to the prepared raw material solution to adjust the pH to 3.5, and after thoroughly mixing and dispersing with a homogenizer (IQA, Ultra Tarrax T50), it is transferred to a flask and stirred with a three-one motor in a heating oil bath. While heating to 40 ° C. and holding at 40 ° C. for 60 minutes, 300 parts by mass of the resin particle dispersion was further added and gently stirred at 60 ° C. for 2 hours. Thus, a photosensitive / thermosensitive capsule dispersion (1) was obtained.
The volume average particle size of the photosensitive / thermosensitive capsules dispersed in this dispersion was 3.53 μm. Further, spontaneous color development of the dispersion was not confirmed during the preparation of this dispersion.

-Preparation of photosensitive / thermosensitive capsule dispersion (2)-
-Microcapsule dispersion (2): 150 parts by mass-Photocurable composition dispersion (2): 300 parts by mass-Polyaluminum chloride: 0.20 parts by mass-Ion exchange water: 300 parts by mass A photosensitive / thermosensitive capsule dispersion (2) was obtained in the same manner as in the preparation of the photosensitive / thermosensitive capsule dispersion (1) except that the components were used.
The volume average particle size of the photosensitive / thermosensitive capsules dispersed in this dispersion was 3.52 μm. Further, spontaneous color development of the dispersion was not confirmed during the preparation of this dispersion.

-Preparation of photosensitive / thermosensitive capsule dispersion (3)-
-Microcapsule dispersion (3): 150 parts by mass-Photocurable composition dispersion (3): 300 parts by mass-Polyaluminum chloride: 0.20 parts by mass-Ion exchange water: 300 parts by mass A photosensitive / thermosensitive capsule dispersion (3) was obtained in the same manner as in the preparation of the photosensitive / thermosensitive capsule dispersion (1) except that the components were used.
The volume average particle size of the photosensitive / thermosensitive capsules dispersed in this dispersion was 3.47 μm. In addition, spontaneous color development of the dispersion was not confirmed during the preparation of this dispersion.

Photosensitive / thermosensitive capsule dispersion (1): 750 parts by mass Sensitive / thermosensitive capsule dispersion (2): 750 parts by mass Photosensitive / thermosensitive capsule dispersion (3): 750 parts by mass The flask was transferred to a flask, heated to 42 ° C. while heating in the flask, and maintained at 42 ° C. for 60 minutes, and then 100 parts by mass of the resin particle dispersion was further added and gently stirred.
Thereafter, the pH in the flask was adjusted to 5.0 with a 0.5 mol / liter sodium hydroxide aqueous solution, and then heated to 55 ° C. while stirring was continued. During the temperature rise to 55 ° C, the pH in the flask usually drops to 5.0 or lower, but here, an aqueous sodium hydroxide solution is added dropwise to keep the pH from dropping to 4.5 or lower. did. This state was maintained at 55 ° C. for 3 hours.

After completion of the reaction, the mixture was cooled, filtered, sufficiently washed with ion exchange water, and then solid-liquid separated by Nutsche suction filtration. Then, it was redispersed in 3 liters of ion exchange water at 40 ° C. in a 5 liter beaker, and stirred and washed at 300 rpm for 15 minutes. This washing operation was repeated 5 times, followed by solid-liquid separation by Nutsche suction filtration, followed by freeze-drying for 12 hours to obtain toner particles in which photosensitive / thermosensitive capsules were dispersed in a styrene resin. When the particle diameter of the toner particles was measured with a Coulter counter, the volume average particle diameter D50v was 15.2 μm.
Subsequently, 1.0 part by mass of hydrophobic silica (manufactured by Cabot, TS720) was added to 50 parts by mass of the toner particles, and mixed with a sample mill to obtain an externally added toner.

(Developer)
As a carrier, 30% by mass of styrene / acrylic copolymer (number average molecular weight: 23000, weight average molecular weight: 98000, Tg: 78 ° C.) and granular magnetite (maximum magnetization: 80 emu / g, average particle size: 0.5 μm) 70% by mass kneaded, pulverized and classified to a volume average particle size of 100 μm, weighed the toner and the toner concentration to 5% by mass, mixed with a ball mill for 5 minutes, and developed. 1 was obtained.

(Image formation)
An image forming apparatus provided with a light shielding section 73 as shown in FIG. 8 was prepared.
As the photoreceptor 10, a gallium chloride phthalocyanine is used as the charge generation layer, and N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1, a charge transport layer is formed around an aluminum drum having a diameter of mm. 1 ′] biphenyl-4,4′-diamine-containing multilayer organic photosensitive layer having a film thickness of 25 μm was used. Further, as the charging device 12, a charging roll having a roll resistance of 10 Ωcm was used.

  As the exposure device 14, an LED image bar having a wavelength of 780 nm capable of forming a latent image with a resolution of 600 dpi was used. The developing device 72 includes a metal sleeve for two-component magnetic brush development and can perform reverse development. The toner charge amount when the developer 1 was loaded in the developing unit was about −5 to −30 μC / g.

The color-information providing device 28, the peak wavelength of 405 nm (exposure ^{amount: 0.2mJ / cm 2), 532nm} ( exposure ^{amount: 0.2mJ / cm 2), 657nm} ( exposure amount: 0.4mJ / cm ²⁾ light Is an LED image bar with a resolution of 600 dpi.
The transfer device 18 includes a semiconductive roll formed by coating a conductive elastic body on the outer periphery of a conductive core material as a transfer roll. The conductive elastic body is made by dispersing two types of carbon black consisting of ketjen black and thermal black in an incompatible blend formed by mixing NBR and EPDM, and has a roll resistance of 10 ^8.5 Ωcm, The Asker C hardness is 35 degrees.

  The fixing device 22 was a fixing device used in DocuPrint C1616 manufactured by Fuji Xerox Co., Ltd., and was arranged at a position 30 cm from the point of coloring information application. Moreover, as the light irradiation means 24, the high-intensity shakasten containing the three wavelengths of the said coloring information provision apparatus was used, and the irradiation width was 5 mm.

The printing conditions were set as follows by the image forming apparatus having the above configuration.
Photoconductor linear velocity: 10 mm / sec.
Charging conditions: The surface potential of the photoconductor was set to −700V.
-Exposure: Exposure was performed with a logical sum of image information for four colors of Y, M, C, and black, and the potential after the exposure was about -50V.
Development bias: A rectangular wave of alternating current Vpp 1.2 kV (3 kHz) is superimposed on direct current −330V.
Developer contact conditions: peripheral speed ratio (development roll / photoreceptor) 2.0, development gap 0.5 mm, developer weight on the development roll 400 g / m ² , toner development amount on the photoreceptor was solid The image was 5 g / m ² .
Transfer bias: DC + 800V applied.
Fixing temperature: The fixing roll surface temperature is set to 180 ° C.
-Light irradiation device illuminance: 130000 lux.

  In this image forming apparatus, due to the necessity of maintenance, a link mechanism (not shown) is operated by an external operation, and the developing device 72 is moved away from the photosensitive member 10 and retracted to the light shielding section 73, and the upper portion of the shielding section 73 after retraction. The front opening of the light shielding section 73 was shielded by the shutter 74. Thereafter, the panel cover of the apparatus was opened, and after maintenance for about 5 minutes, the cover was closed and returned to the initial state again.

  Under the above conditions, a chart having a gradation image portion was printed for each color of Y, M, C, R, G, B, and K. The coloring information was given to the toner in the combinations shown in Table 1 below (indicating that the toner is colored in a desired color when the LED marked with a circle emits light). In addition, in order to control the color density by the light emission intensity or the light emission time, time width modulation in which the time of one dot is divided into eight is adopted.

For each color of R, G, B, and K, the color reproducibility was examined by a 5% to 100% gradation chart in 5% increments, but in any color, the color balance is good and the color reproducibility is excellent. The toner was not altered by opening the device.
The above operation was repeated, but no image defect based on toner alteration was observed.

<Example 2>
In the first embodiment, a developing device unit 70 having a shutter 66 that shields the opening of the developing device unit as shown in FIG. 4 is applied as a developing device by removing the light shielding section 73 and the link mechanism for retraction, and before maintenance. The apparatus was opened in the same manner except that the light was blocked by closing the shutter 66, and the same evaluation was performed.
As a result, the color balance was excellent in all colors and the color reproducibility was excellent, and no toner alteration due to the opening of the apparatus was observed.

<Example 3>
In the first embodiment, the light shielding section 73 and the link mechanism for retreating are removed, and a developing unit 80 having a SUS scraper 88 as shown in FIG. 5 is applied as a developing device, and the scraper mechanism is operated before maintenance. The apparatus was opened in the same manner except that light was shielded by peeling off the developer on the developing roll, and the same evaluation was performed.
As a result, the color balance was excellent in all colors and the color reproducibility was excellent, and no toner alteration due to the opening of the apparatus was observed.

<Example 4>
In the first embodiment, the light shielding section 73 and the link mechanism for retreating are removed, and a developing unit 90 having an internal magnetic pole 93 and a magnetic blade 98 directly above the developing roll as shown in FIG. 6 is applied as a developing device. Prior to maintenance, the apparatus was opened in the same manner except that the magnetic pole moving mechanism was activated and the magnetic pole 98 disposed between the magnetic poles 98 was opposed to the magnetic blade 98 to form a magnetic shield to perform the developer peeling operation. Similar evaluations were made.
As a result, the color balance was excellent in all colors and the color reproducibility was excellent, and no toner alteration due to the opening of the apparatus was observed.

<Example 5>
In the first embodiment, a developing device unit 100 provided with a copper electrode 108 in the vicinity of the developing position of the developing roll 104 as shown in FIG. Then, before the maintenance, the apparatus was opened in the same manner except that a voltage of +1 V was applied to the electrode 108 and the developing roll 104 was rotated for 30 seconds to consume the toner in the developer. went.
As a result, the color balance was excellent in all colors and the color reproducibility was excellent, and no toner alteration due to the opening of the apparatus was observed.

<Example 6>
In Example 1, the apparatus was opened in the same manner except that the developer was not retracted to the light shielding section 73 before maintenance. Thereafter, the developing bias was applied without rotating the developing roll to develop the toner in the light exposed portion on the photoconductor 10, and unnecessary toner was collected by the cleaner 20 without performing the transfer. Subsequently, the apparatus was reset as it was, and the same evaluation was performed.
As a result, the color balance was excellent in all colors and the color reproducibility was excellent, and almost no toner deterioration due to the opening of the apparatus was observed.

<Comparative Example 1>
In Example 1, the apparatus was opened in the same manner except that the developer was not retracted to the light-shielding section 73 before maintenance, the apparatus was reset as it was, and the same evaluation was performed.
As a result, an image with a low density was obtained as a whole, and the color reproducibility for each color was also deteriorated, and obvious toner alteration due to the opening of the apparatus was recognized.

  As described above, even if the light shielding is performed according to the embodiment of the present invention before maintenance or the like, and the apparatus is opened thereafter, the toner is hardly deteriorated by light exposure, and particularly high color recording sensitivity such as F toner is high. It can be seen that even when toner is used, a stable image can be obtained against repeated opening of the apparatus.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus of the present invention. It is a circuit block diagram of a printing control unit. It is a schematic block diagram which shows another example of the image forming apparatus of this invention. It is a schematic diagram which shows an example of the light-shielding means in this invention, (A) shows the state before light-shielding, (B) shows the state after light-shielding. It is a schematic diagram which shows another example of the light-shielding means in this invention. It is a schematic diagram which shows another example of the light-shielding means in this invention. It is a schematic diagram which shows another example of the light-shielding means in this invention. It is a schematic block diagram which shows another example of the light-shielding means in this invention. 4A and 4B are schematic diagrams illustrating an example of a developer removing unit in the present invention, where FIG. 5A illustrates a state before toner removal, and FIG. 5B illustrates a state after toner removal. 4A and 4B are schematic diagrams illustrating another example of a developer removing unit in the present invention, where FIG. 5A shows a state before toner removal, and FIG. 4B shows a state after toner removal. 2A and 2B are schematic diagrams for explaining a toner color development mechanism, in which FIG. 1A shows a color development portion and FIG. 2B shows an enlarged state thereof.

Explanation of symbols

10, 62, 82, 92, 102 Photoconductor 12 Charging device 14 Exposure device 16 Development device 18 Transfer device 20 Cleaner 22 Fixing device 24 Light irradiation device 26 Recording medium 28 Color information providing device 34 Color information providing exposure head 36 Printer controller 38 Exposure unit 40 OR circuit 42 Oscillation circuit 44 Color development control circuit 52 Color development agent 54 Developer monomer 56 Photopolymerization initiator 60 Color development unit (photosensitive / heat-sensitive capsule)
64, 84, 94, 104 Developing roll (developer carrier)
65 Opening 66 Shutter 68, 86, 96, 106 Developer 70, 72, 80, 90, 100 Developer unit 73 Light-shielding section 88 Scraper 93 Internal magnetic pole 98 Magnetic blade 108 Electrode

Claims (2)

An image forming apparatus using toner that is controlled to maintain a colored state or a non-colored state by providing coloring information by light,
An image carrier, means for forming a latent image on the surface of the image carrier, developing means for converting the latent image into a toner image with a developer containing toner, and light on the toner image formed on the surface of the image carrier. Coloring information imparting means for imparting coloration information by means of, a transfer means for transferring the toner image to which the coloration information is imparted to the surface of the recording medium, and fixing the toner image transferred to the surface of the recording medium by heat and / or pressure Fixing means for performing color development, and color development means for coloring the toner image to which the color development information is imparted by heating,
Furthermore, it has a shielding means for shielding from light that exists within the developer apparatus in the developing unit,
The light shielding means, wherein a voltage applied to the electrode provided in proximity to the surface of the developer carrying member in the developing means, the image forming apparatus characterized in that it have a mechanism for removing the toner of the developer carrying member surface . An image forming apparatus using toner that is controlled to maintain a colored state or a non-colored state by providing coloring information by light,
An image carrier, means for forming a latent image on the surface of the image carrier, developing means for converting the latent image into a toner image with a developer containing toner, and light on the toner image formed on the surface of the image carrier. Coloring information imparting means for imparting coloration information by means of, a transfer means for transferring the toner image to which the coloration information is imparted to the surface of the recording medium, and fixing the toner image transferred to the surface of the recording medium by heat and / or pressure Fixing means for performing color development, and color development means for coloring the toner image to which the color development information is imparted by heating,
And a light shielding means for shielding the developer in the developing means from light existing inside the apparatus,
The light blocking means, images forming device you and a mechanism for at least retracting the developing means to the light shielding compartments.