JP2006215194A - Image forming method and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming method and an image forming apparatus by which an image comprising a heat-foamable toner formed on a recording medium can be easily and efficiently foamed and raised without scarifying energy saving performance or productivity so as to form a stereoscopic image only based on the toner image or an image including the stereoscopic image. <P>SOLUTION: The image forming method and the image forming apparatus are characterized in that: on forming a raised stereoscopic image by forming an image comprising at least a heat-foamable toner on a non heat-foamable recording material (P) and then heating to foam the heat-foamable toner image, the heat-foamble toner contains an IR absorbent; and a heat-foamable toner layer (T(H)) comprising the heat-foamable toner containing the IR absorbent and formed by a first imaging forming means (10) is irradiated with at least IR rays by an irradiating means (8). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming method and an image forming method capable of forming a raised three-dimensional (bumped) image by heating and foaming an image made of at least a heat-foamable toner formed on a non-heat-foamable recording medium. In particular, the present invention relates to an apparatus, and in particular, an image forming method suitable for forming only a three-dimensional image based on the toner image so as to easily and efficiently foam the thermally foamable toner image, and an image including the same. The present invention relates to an image forming apparatus.

  Conventionally, the applicant has used an image forming apparatus such as a general printer, a copying machine, or a multifunction machine to which an electrophotographic method or an electrostatic recording method is applied, and has a non-thermal foaming property as represented by plain paper. Have proposed a method of forming a three-dimensional image that is raised by forming an image composed of at least a heat-foamable toner on the recording medium and then foaming it by heating (Patent Documents 1, 2, etc.). .

  In Patent Document 1, an image made of an image forming toner contained so that the foaming agent is not substantially exposed on the toner surface is formed on a recording medium through an electrophotographic process or the like, and then a heat fixing process is performed. A method for forming a stereoscopic image by foaming a foaming agent contained in the toner, a forming apparatus for the method, and the like have been proposed.

  In Patent Document 2, a color image made of a non-foamable full-color toner is formed on an image made of a heat-foamable toner to be formed on a recording medium, and then a heat-fixing process is performed to foam the heat-foamable toner. A method and apparatus for forming a three-dimensional image and forming a color image by melting and fixing a non-thermally foamable full-color toner have been proposed.

  In each of these three-dimensional image forming methods and forming apparatuses, only an image made of heat-foamable toner or a toner image containing the same is passed through a fixing device such as a pair of fixing rolls and heated and pressed. The thermally foamable toner is foamed (thermally expanded) and melted to be fixed to a recording medium.

JP 2000-131875 A JP 2002-244384 A JP 2002-174924 A JP 2003-270860 A

  However, such a three-dimensional image forming method and its forming apparatus have the following problems.

  First, in order to thermally expand the foaming agent in the thermally foamable toner to obtain a sufficiently high stereoscopic image, a larger amount of thermal energy is applied than when fixing an image made of non-thermally foamable colored toner. Must. As a result, it has been difficult to easily obtain a stereoscopic image having a sufficient height.

  On the other hand, when fixing is performed under heating conditions optimized to form a sufficiently high three-dimensional image (e.g., increase in fixing temperature, extension of fixing time), it is made of a non-thermally foamable colored toner. Since excessive heat energy is applied to the image (image part), the colored toner melted by the heating may adhere to the fixing roll and the like and may not be fixed on the recording medium. It may lead to defects.

  For this reason, when an image made of a heat-foamable toner and an image made of a non-heat-foamable colored toner are formed on the same recording medium, both images are best. It was difficult to form in a state.

  In addition, when increasing the thermal energy applied for fixing the heat-foamable toner, it is necessary to increase the heating temperature during fixing or to decrease the fixing speed. As a result, energy saving and image formation productivity are achieved. There was also the problem of being inferior in terms of.

  Incidentally, in the past, including the proposal by the present applicant, as a method for forming a normal flat image (an image that is not a three-dimensional image) and an apparatus for forming the image, the recording medium contains an infrared absorber. There has been proposed an image forming method in which an image is formed with a colored toner, and then the toner image is irradiated with infrared rays or the like to be photofixed (Patent Documents 3 and 4). However, none of Patent Documents 3 and 4 according to this proposal shows a content relating to forming a stereoscopic image using a heat-foamable toner.

  The present invention has been made in view of the above-described problems and the like, and an image formed of a heat-foamable toner formed on a recording medium can be easily and efficiently performed without energy saving or sacrifice of productivity. It is an object of the present invention to provide an image forming method and an image forming apparatus capable of forming only a three-dimensional image based on the toner image or an image including the three-dimensional image based on the toner image.

  In addition to this, when the image made of the heat-foamable toner and the image made of the non-heat-foamable color toner are formed on the recording medium in a mixed manner, the image of both of them is best. It is also an object of the present invention to provide an image forming method and an image forming apparatus which can be formed in a desired state.

  According to the image forming method of the present invention, after forming an image composed of at least a thermally foamable toner on a non-thermally foamable recording medium, the thermally foamable toner image is heated and foamed to form a raised stereoscopic image. At this time, a thermal foamable toner containing an infrared absorbent is used as the thermal foamable toner, and at least infrared rays are irradiated to the thermal foamable toner layer formed of the thermal foamable toner containing the infrared absorbent. It is a feature.

  Here, the non-thermally foamable recording medium is a medium that can form an image made of toner (developer), and has no physical property that foams (thermally expands) when heated. For example, recording paper such as plain paper.

  The image made of the heat-foamable toner can be formed on the entire surface of the recording medium, but is usually partially formed in the corresponding area of the recording medium corresponding to the stereoscopic image to be formed. This thermally foamable toner image may be formed alone on a recording medium, or may be formed in combination with an image made of non-thermally foamable colored toner. The thermally foamable toner image is formed with a desired layer thickness. The infrared absorbent contained in the heat-foamable toner preferably has a light absorption characteristic with respect to wavelengths in a non-visible region as will be described later.

  According to such an image forming method, when a region where a heat-foamable toner image containing an infrared absorbent is formed on a non-thermo-foamable recording medium is irradiated with infrared rays, the heat-foamable toner image The inside infrared absorber absorbs infrared rays and generates heat instantaneously, and the heat acts on the thermally foamable toner. As a result, the thermally foamable toner image is heated by the heat generating action of the infrared absorbent and is foamed (expanded) to form a three-dimensional image.

  In the image forming method, an image made of a non-thermally foamable colored toner may be formed in a region where the thermally foamable toner layer is not formed.

  When a non-thermally foamable colored toner image is formed in a non-formation region of such a thermally foamable toner image, a portion of the thermally foamable toner image is obtained as a foamed and raised stereoscopic image. In the area of the recording medium where no toner exists, the colored toner image portion is obtained as a (non-stereoscopic) colored image in a state where it does not rise due to foaming of the thermally foamable toner image. Incidentally, in the image forming method described above, it is possible to form a non-thermally foamable colored toner image on the thermally foamable toner layer so as to overlap the region where the thermally foamable toner layer is formed. In this case, the colored toner image is obtained as a colored three-dimensional image that is raised by the foaming of the thermally foamable toner image.

  On the other hand, the image forming apparatus of the present invention is formed by a first image forming unit that forms an image made of a heat-foamable toner containing an infrared absorber on a non-thermally foamable recording medium, and the first image forming unit. An apparatus having irradiation means for irradiating at least infrared rays to a thermally foamable toner image, which can form a raised stereoscopic image by heating and foaming the thermally foamable toner image formed on the recording medium. It is characterized by.

  Here, the first image forming means is not particularly limited as long as it can form a thermally foamable toner image containing an infrared absorbent on a non-thermally foamable recording medium according to desired image information. It is not something. For example, a latent image is formed on a latent image carrier in accordance with image information for a stereoscopic image using an image forming method such as an electrophotographic method or an electrostatic recording method, and the latent image is developed with the heat-foamable toner. Thus, a heat foamable toner image can be formed, and the toner image can be formed (transferred) onto a recording medium.

  The irradiation unit may be any unit that can irradiate infrared rays necessary for the thermally foamable toner image formed by the first image forming unit. Therefore, it is preferable that the infrared ray irradiated from the irradiation unit is an infrared ray having a wavelength characteristic including at least a wavelength region that can be absorbed by the infrared absorbent contained in the thermally foamable toner.

  According to such an image forming apparatus, a thermally foamable toner image containing an infrared absorbent is formed on a non-thermally foamable recording medium by at least the first image forming means, and finally, the thermally foamable toner image is formed on the thermally foamable toner image. Infrared rays are emitted from the irradiation means. As a result, the infrared absorbent in the thermally foamable toner image absorbs infrared rays and generates heat instantaneously, and the heat acts on the thermally foamable toner. A three-dimensional image (stereoscopic image) is formed by heating (expanding) and raising due to heat generated by the absorbent.

  In addition, this image forming apparatus may be configured to include a second image forming unit that forms an image made of a non-thermally foamable colored toner in a region where a thermally foamable toner image is not formed.

  Here, the second image forming means may be any device that can form a non-thermally foamable colored toner image in a region where the thermally foamable toner image is not formed. For example, an image forming apparatus similar to the first image forming means (which differs in that a non-thermally foamable colored toner is used instead of the thermally foamable toner) can be used.

  In the case where such second image forming means is included, a three-dimensional image in which the thermally foamable toner image portion is foamed and formed is formed, while in the region of the recording medium where the three-dimensional image does not exist, A (non-stereoscopic) colored image is formed in which the portion of the colored toner image is not raised due to foaming of the thermally foamable toner image. Incidentally, in the image forming apparatus, a non-thermally foamable colored toner image is superimposed on the thermally foamable toner layer by the second image forming unit on the region where the thermally foamable toner layer is formed. It is also possible to form.

  According to such an image forming method and apparatus for forming an image according to the present invention, a heat-foamable toner image containing an infrared absorbent is formed and irradiated with infrared rays. Since the three-dimensional image is formed by heating the toner image, the heat-foamable toner image formed on the non-thermo-foamable recording medium is easily and efficiently foamed and raised, and only the three-dimensional image based on the toner image is used. An image including can be formed.

  In particular, it is also possible to heat and foam a heat-foamable toner image by the exothermic action of an infrared absorber contained in the toner image only by irradiating infrared rays. Alternatively, even when the fixing device is used in combination, it is not necessary to excessively increase the heat energy applied at the time of fixing. This eliminates the need for a heat source for heating at an unnecessarily high temperature for fixing the toner image, which is advantageous in terms of energy saving, and requires that the processing (passing) speed at the time of fixing be lower than usual. It is also advantageous from the viewpoint of productivity. Furthermore, when a non-thermally foamable colored toner image is formed at the same time, the colored toner image is not heated with excessive heat energy as in the case of the prior art described above. As a result, there is no concern that the color toner will adhere to a fixing roll or the like and cause image quality defects.

  FIG. 1 shows an outline of a digital color multifunction peripheral according to an embodiment to which the present invention is applied.

[Configuration of the entire MFP]
The digital color multifunction peripheral 1 is a color image forming apparatus having at least a copying function and a printing function, and can form a normal (planar) image composed of a single color or multiple colors on a recording sheet P. In addition to the above, a three-dimensional image (stereoscopic image) can be formed. Reference numeral 2 in FIG. 1 denotes a main body that constitutes the image output unit of the multifunction machine 1.

  In the multifunction device 1, a document reading device 3 that reads an image of a document is installed on the upper side of the image output unit main body 2. The document reading device 3 passes through the reading slit portion by a document placed on a platen glass as a document placement surface (not shown) or an automatic document transport device (not shown) that automatically feeds the documents one by one. The conveyed document is illuminated by a light source, and reflected light from the document is made incident on an image reading element such as a CCD through a predetermined mirror, a reduction optical system, and the like. Thereby, the color material reflected light image of the original is read at a predetermined dot density (for example, 16 dots / mm) by the image reading element.

  Further, an operation panel 4 as a user interface (UI) is installed on the upper side of the main body 2 of the image output unit (for example, the front side portion of the document reading device 2). The operation panel 4 includes various buttons for performing an input operation, a touch-type liquid crystal panel for performing an input operation and displaying various information, and the like. In particular, in the liquid crystal panel, while an operation procedure and a message are output to the user, an instruction content from the user regarding the operation is input by touching a predetermined area of the panel with a finger.

  On the other hand, an image processing device 5 is installed inside the image output unit main body 2. The image processing device 5 is configured to perform predetermined processing on image data (signals) read by the document reading device 3 and image data input from a personal computer (PC) 100 (described later) connected to the multi function device 1. Image (signal) processing is performed to generate final image data. In particular, the image processing apparatus 5 has an image data processing function for forming a stereoscopic image as will be described later in addition to a normal image data processing function for forming a monochromatic or multicolor image. Yes. The image processing apparatus 5 can also perform image processing corresponding to a user's input instruction, and uses the touch-type liquid crystal panel or the like in the operation panel 4 described above as the input means.

  Further, inside the image output unit main body 2, a plurality of image forming units 10 for forming various toner images, and a recording sheet after the toner images formed by these image forming units 10 are primarily transferred. An intermediate transfer unit 20 having an intermediate transfer belt 21 that conveys to a position (secondary transfer portion) for secondary transfer to P is installed. In this embodiment, a plurality of image forming units 10 are arranged in a state of being arranged in series along the rotation direction of the belt 21 at a position below the intermediate transfer belt 21 in the intermediate transfer unit 20.

  In any of the image forming units 10, basically, a photosensitive drum 11 provided with an organic photosensitive layer or the like on the outer peripheral surface of a drum-like substrate that is rotationally driven in a predetermined direction, and the surface of the photosensitive drum 11 are uniformly charged. The charging device 12, the write exposure device 13 for exposing the surface of the charged photosensitive drum 11 to light based on image data sent from the image processing device 5 to form an electrostatic latent image, and the electrostatic latent image. And a developing device 14 for developing the surface of the photosensitive drum 11 with a predetermined toner, and a drum cleaning device 16 for cleaning the surface of the photosensitive drum 11. Among these, the developing device 14 is a two-component developing type developing device that performs development using a two-component developer containing toner and carrier. A developing device of a component developing system may be used.

  In this embodiment, as the image forming unit 10, an image forming unit 10H that forms a toner image (hereinafter also referred to as “IR heat-expandable toner image”) made of a heat-expandable toner containing an infrared absorber (IR); At least three types of image forming units 10W that form toner images (hereinafter also referred to as “colored toner images”) made of non-thermally foamable colored toner are used. As the image forming unit 10W for forming the color toner image, an image made up of each color toner of yellow (Y) toner, magenta (M) toner, cyan (C) toner and black (K) toner is formed exclusively. Four image forming units 10Y, 10M, 10C, and 10K are used. The five image forming units 10 are arranged in the order of the image forming units 10H, 10K, 10C, 10M, and 10Y toward the upstream side in the rotation direction of the intermediate transfer belt 21 when viewed from the secondary transfer unit.

  Incidentally, the image forming unit 10H uses another developing device 14H (10Y, 10M, 10C) for forming a colored toner image in that a developing device 14H that stores a heat-foamable toner described later is used as each developing device 14. 10K), and other configurations are basically the same as those of the image forming unit 10W.

  The intermediate transfer unit 20 wraps an endless intermediate transfer belt 21 around a drive roll 22, a backup roll 23 of a secondary transfer unit, a plurality of driven rolls 24, 25,... With a predetermined tension. 24 and the driven roll 25 are installed so as to be in contact with the photosensitive drum 11 in each image forming unit 10. The intermediate transfer belt 21 is, for example, an endless belt having a two-layer structure in which a surface layer of silicone rubber or the like is laminated on a belt base material such as a polyimide film containing a conductive material and the like and adjusted in volume resistivity. Thus, it is configured to run in the direction of the arrow by the rotational power of the drive roll 22.

  A primary transfer roll 27 for electrostatically transferring each toner image formed on the photosensitive drum 11 of each image forming unit 10 to the intermediate transfer belt 21 is installed on the inner peripheral surface side of the intermediate transfer belt 21. ing. A primary transfer bias having a polarity opposite to the charging polarity of the toner image on the photosensitive drum 11 is applied to the primary transfer roll 27 from a bias power supply device (not shown). Further, on the outer peripheral surface side of the intermediate transfer belt 21, a secondary transfer roll 28 for pressing the belt 21 against the backup roll 23 to form a secondary transfer nip portion (pressure contact area) of the secondary transfer portion is arranged. It is installed. A power supply member for supplying a secondary transfer bias having the same polarity as the charging polarity of the toner image on the intermediate transfer belt 21 from a bias power supply device (not shown) is in contact with the conductive axis of the backup roll 23. It is installed in a state. Further, a belt cleaning device 29 for cleaning the surface of the belt 20 is installed at a position facing the drive roll 22 of the intermediate transfer belt 21.

  Below the image forming unit 10, there is a paper feeding device 6 that accommodates a non-thermally foamable recording sheet P of a predetermined size, type, etc. and feeds it one by one toward the secondary transfer section. Has been placed. The sheet feeding device 6 stacks and stores a plurality of recording sheets P in one or a plurality of storage cassettes 61 that are supported so as to be able to be put in and out of the main body 2 of the multifunction machine 1, and is at the top of the storage cassette 61. The recording sheets P are sent out one by one from the cassette 61 by the feeding device 62 in order. The recording sheet P sent out from the paper feeding device 6 is conveyed through a predetermined paper feeding conveyance path formed between the paper feeding device 6 and the secondary transfer nip portion, and is arranged on the front side of the secondary transfer portion. The resist roll pair 55 is conveyed.

  Further, in the inside of the image output unit main body 2, the recording sheet P after the toner image is secondarily transferred by the secondary transfer unit is disposed on the upper side, which is the downstream side in the conveyance direction of the recording sheet P from the secondary transfer unit. A fixing device 7 for performing a fixing process is installed. This fixing device 7 is of a thermo-pressure type in which a recording sheet P carrying an unfixed toner image is heated and pressed to fix it, and is basically rotated by being heated to a predetermined temperature by a heating source (not shown). The main part of a heating roll 71 that rotates and a pressure member (pressure roll, pressure belt, etc.) 72 that rotates while forming a fixing nip portion (pressure contact area) by pressing against the heating roll 71 with a predetermined pressure Is configured.

  Further, an optical fixing device 8 for irradiating the recording sheet P carrying the toner image with infrared rays is disposed on the upper side of the main body 2 on the downstream side in the recording sheet conveyance direction of the fixing device 7. ing. The light fixing device 8 may be any device that can irradiate infrared rays, and is configured using, for example, an infrared lamp, a xenon lamp, or the like. The optical fixing device 8 and the fixing device 7 are configured to be used properly (single use or combined use) depending on conditions such as the type of image to be formed. In fact, the photofixing device 8 is always used when a thermally foamable toner image containing an infrared absorber is formed.

  Further, on the upper surface of the main body 2 of the image output unit, a discharge storage surface portion 2A that stores the recording sheets P discharged outside the main body after image formation in a stacked state is formed. In addition, a discharge roll pair 56 for discharging the recording sheet P after fixing toward the discharge storage surface portion 2A is installed on the upper portion of the main body 2.

  The computer 100 connected to the multifunction machine 1 has a general hardware configuration and a software configuration such as basic software and application software. Software resources include stereoscopic image editing software for creating or editing stereoscopic images, character drawing creation software for creating characters and drawings, and software for converting and transferring image data to output data compatible with a printer. Have.

[Toner to be used]
Here, the heat-foamable toner is a fine particle containing at least a binder resin, a foaming agent, and an infrared absorber, and is preferably a type of toner in which the foaming agent is not substantially exposed on the toner surface. . In the case of using a thermally foamable toner in which the foaming agent is not substantially exposed on the surface, it has high thermal expansibility and can maintain good adhesion to the recording sheet and charging stability.

  The binder resin of the foamable toner is not particularly limited, and a resin generally used as a toner resin can be used. Specific examples include polyester resins, styrene resins, acrylic resins, styrene / acrylic resins, silicone resins, epoxy resins, diene resins, phenol resins, ethylene / vinyl acetate resins, and polyester resins are preferred.

  The foaming agent is not particularly limited, and any foaming agent can be used as long as it expands by heat. Further, the foaming agent may be solid at room temperature or liquid. Furthermore, the foaming agent is not limited to a material composed of a single substance, and may be a material composed of a plurality of substances or a functional material such as microcapsule particles. The foaming temperature of the foaming agent varies depending on which apparatus is used to form a three-dimensional image. However, a three-dimensional image is formed by a normal image forming apparatus that forms a toner image composed of non-thermally foamable colored toner. In the case of forming the toner image, it is preferably a temperature not higher than the fixing temperature necessary for heat-fixing the toner image.

  As the infrared absorber, one having no light absorption property in the visible light region up to a wavelength of 400 to 700 nm that can be seen with the naked eye and having the light absorption property in a non-visible region of a wavelength of 700 nm or more is preferable. used. As the infrared absorbing material having light absorption characteristics in the invisible range, specifically, glass powder doped with CuO, or a material in which Cu ions are introduced into a polymer can be used. Note that the use of an infrared absorber having light absorption characteristics in the visible light region is not appropriate in that there is a problem that the color developability of the colored toner image is impaired.

  Such heat-expandable toners, for example, are produced by suspending and dispersing an oil phase in which at least a binder resin, a foaming agent, and an infrared absorber are dissolved or dispersed in a solvent into an aqueous phase. And a process including a step of removing the solvent from the particles. In addition, it may be produced by a production method including a step of subjecting a binder resin monomer in which at least a foaming agent and an infrared absorber are dissolved or dispersed to suspension polymerization in an aqueous phase. The content ratio of the infrared absorbent in the heat-foamable toner can be arbitrarily set, and is, for example, a ratio of 0.5 to 90% by weight with respect to the whole toner.

  In this embodiment, as a heat-foamable toner, 50% by weight of a polyester polymer as a binder resin, 25% by weight of an isobutane-containing acrylic resin (Expansel 051) as a foaming agent, and infrared rays are used. A white toner (average particle diameter: about 6 μm) obtained by a suspension polymerization method including a step of suspension polymerization of 25% by weight of an infrared absorber composed of OP frit as an absorber in an aqueous phase was used. In addition, known toners were used as the four color toners.

[Generation of image data such as stereoscopic images]
Next, generation of image data of a stereoscopic image formed in the multifunction machine 1 will be described together with generation contents of a normal colored image.

  First, it is necessary to input original image data that is a source of a stereoscopic image. As an input format, a method of inputting information obtained by reading an original image from the original reading device 3 and a combination machine 1 are connected. There is a method of inputting from a predetermined computer 100.

  In the method of inputting from the document reader 3, two types of documents, a color or monochrome image document and a stereoscopic image document, are prepared as documents, and color or monochrome image data and stereoscopic image data are prepared from each document. There are cases where both reading and inputting are performed, and cases where both color or monochrome image data and stereoscopic image data are generated from one type of original document such as a normal color or monochrome image original.

  In the case of the former input method, as shown in FIG. 2, a normal color or monochrome original is first subjected to a color material reflected light image, for example, red (R), green (G), blue (B ) Of three-color original reflectance data (for example, 8 bits each). Subsequently, the correction processing unit 51 of the image processing apparatus 5 performs correction processing such as shading correction, position shift correction, brightness / color space conversion, and gamma correction on the three color document reflectance data, and then the image processing apparatus. The color image data of each color toner is generated by converting the image data for each color of Y, M, C, and K in the 5 color image generation unit 52.

  On the other hand, a stereoscopic image original is read as three-color original reflectance data by the original reading device 3, and then the original reflectance data is subjected to shading correction and positional deviation correction by the correction processing unit 51 of the image processing device 5. The correction process such as is performed in the same manner. Subsequently, the stereoscopic image generation unit 55 of the image processing apparatus 5 calculates saturation and hue information in the corrected document reflectance data, and uses the calculated information to calculate the height (layer thickness) by a predetermined procedure. By converting to data, stereoscopic image data for the heat-expandable toner to be formed to be superimposed on a color or monochrome image (in addition to forming a colored image alone) is generated.

  In the case of the latter input method, a normal color or monochrome image original which is one type of original is first converted into three-color original reflectance data by the original reading device 2 in the same manner as in the former input method. read. Subsequently, the same correction processing is performed on the three-color original document reflectance data by the correction processing unit 51 of the image processing apparatus 5, and then the color image generation unit 52 converts the image data of each color of Y, M, C, and K into the image data. By performing the conversion, colored image data of each colored toner is generated.

  On the other hand, for the stereoscopic image data, the image data (reflectance data) of the one type of document read by the document reading device 3 is displayed on the liquid crystal panel of the operation panel 4 as a display image, and the displayed liquid crystal is displayed. The user designates an image area that the user wants to make a three-dimensional image with respect to the image content on the panel by an input assisting means such as a touch pen. Subsequently, the designated area is converted from the document reflectance data to the height information data according to the same procedure as in the former input method, so that the stereoscopic image data for the thermally foamable toner image is obtained. Generate.

  In the method of inputting from the computer 100, the user himself / herself uses character drawing creation software, stereoscopic image editing software, or the like, which is a part of software resources in the computer 100, so that the user himself / herself can obtain information as a stereoscopic image in addition to color or monochrome image data. Create stereoscopic image data with. The color or monochrome image data and the stereoscopic image data created in this way are transmitted from the computer 100 to the multi-function device 1, and the correction processing unit 51 of the image processing device 5 is the same as in the case of the input method described above. Is corrected. Subsequently, based on the corrected data, the color image generation unit 52 generates color image data of each color toner, while the stereoscopic image generation unit 55 generates stereoscopic image data. At this time, the stereoscopic image data (H) is also transmitted to the colored image data generation unit 52, and information on the formation area of the stereoscopic image is provided.

  The colored image data and the stereoscopic image data generated through such an input method are subjected to predetermined gradation correction in the output gradation correction unit 53 of the image processing device 5 as necessary. Four color image data (Y, M, C, K) and three-dimensional image data (H) subjected to this gradation correction as needed are sent from the image processing device 5 to each image forming unit 10 (Y, M, (C, K, H).

[Each image forming operation]
Hereinafter, a general color image forming operation and a stereoscopic image forming operation by the image output unit of the multi-function device 1 will be described.

  First, in the multifunction device 1, on the selection screen of the operation button of the operation panel 4, the computer 100, or the like, as an image formation pattern, a pattern that forms only a general color image, a pattern that forms only a stereoscopic image, and its color image Any one of patterns formed by combining three-dimensional images can be arbitrarily selected and executed.

  When any one of these image forming patterns is selected and an instruction to start the image forming operation is input, each image forming unit 10 of the image output unit, for example, the type of image (toner image) to be formed, etc. Regardless of the operation, each toner image is formed similarly in the following manner.

  That is, in each image forming unit 10, after the surface of the photosensitive drum 11 rotating in a predetermined direction is uniformly charged with a predetermined polarity (for example, negative polarity) by the charging device 12, the exposure device 13 is applied to the charged surface. Thus, light corresponding to each image data (color image data and stereoscopic image data in this embodiment) is exposed to form an electrostatic latent image having a predetermined surface potential. Thereafter, the electrostatic latent image is developed with toner charged to a predetermined polarity (for example, negative polarity) supplied from the developing device 14 to form a toner image.

  Specifically, in the image forming units 10Y, 10M, 10C, and 10K, colored toner images composed of yellow toner, magenta toner, cyan toner, and black toner are formed. Further, in the image forming unit 10H, an IR foamable toner image made of a thermally foamable toner containing an infrared absorber (IR) is formed.

  In addition, when a pattern that forms only a colored image is selected as the image forming pattern, at least one of the image forming units 10Y, 10M, 10C, and 10K operates. When an image forming pattern that forms only a stereoscopic image is selected, the image forming unit 10H is activated. Further, when an image forming pattern formed by combining a colored image and a stereoscopic image is selected, at least one of the image forming units 10Y, 10M, 10C, and 10K and the image forming units 10H and 10I are operated.

  In this way, each toner image formed individually by each image forming unit 10 is pressed against the surface of the intermediate transfer belt 21 passing between each photosensitive drum 11 and the primary transfer roll 27 and electrostatic attraction force. The primary transfer is performed sequentially. At this time, on the intermediate transfer belt 21, in principle, the toner image formed by the image forming unit 10 arranged at the position on the most upstream side in the rotation direction of the belt is arranged at the head and sequentially arranged at the downstream position. The respective toner images formed by the respective image forming units 10 are sequentially transferred according to the arrangement order (so as to overlap each other). The surface of the photosensitive drum 11 after the transfer is cleaned by removing residual toner and the like by the drum cleaning device 16.

  Subsequently, the toner image (multiple) transferred to the intermediate transfer belt 21 is conveyed to the secondary transfer nip portion where the secondary transfer roll 28 is in pressure contact with the rotation of the belt. On the other hand, as described above, the recording sheets P are sent out one by one from the paper feeding device 6 to the secondary transfer nip portion and fed by the registration roll pair 55 at a predetermined timing. As a result, in the secondary transfer nip portion, the toner image on the intermediate transfer belt 21 is transferred to the recording sheet P by the press contact force and the electrostatic attraction force. The surface of the intermediate transfer belt 20 after the completion of the secondary transfer is cleaned by removing residual toner and the like by the belt cleaning device 29.

  The recording sheet P onto which the toner image has been transferred in this way is removed from the secondary transfer nip portion and then conveyed toward the fixing device 7, where the fixing nip portion (pressure contact) between the heating roll 71 and the pressure member 72 is conveyed. It is introduced to the area and allowed to pass. As a result, the unfixed toner image is heated and pressed at a predetermined temperature and pressure in the fixing nip portion. At this time, when a color toner image is carried on the recording sheet P, the color toner is heated and melted and fixed on the recording sheet P. Further, when a heat-foamable toner image is carried on the recording sheet P, the heat-foamable toner image is heated and thermally expanded to rise.

  After passing through the fixing device 7, the recording sheet P is conveyed so as to pass through the optical fixing device 8 disposed downstream of the fixing device 7 in the conveying direction. At this time, when it is necessary to perform optical fixing by the optical fixing device 8 (specifically, at least when an IR transparent toner layer is formed), the recording sheet P carrying the toner image from the optical fixing device 8. Infrared rays are radiated. When this infrared irradiation is performed, at least the infrared absorbent contained in the toner constituting the IR thermally foamable toner image generates heat, and as a result, the IR thermally foamable toner image itself is further heated. And expands thermally.

  The recording sheet P after passing through the fixing device 7 and the fixing device 8 is discharged to the discharge storage surface portion 2A which is the outside of the image output portion main body 2. Through the above process, only a desired colored image (in other words, a flat image) made of colored toner is formed on the recording sheet P, or only a thermally foamable toner image is foamed and raised. Only a stereoscopic image (actually a raised portion) is formed, or a desired colored stereoscopic image in which a colored image and a stereoscopic image are appropriately combined is formed.

  In this multifunction device 1, when an image forming pattern that forms only a general colored image is selected, all or a part of the image forming units 10Y, 10M, 10C, and 10K operate as described above. Then, a colored toner image T (Y, M, C, K) based on the colored image data is formed and transferred onto the recording sheet P, and then fixed by passing through a hot-pressure fixing device 7 and applying heat and pressure. Is called. In this case, since the recording sheet P after passing through the fixing device 7 does not need to be fixed by the optical fixing device 8 thereafter, it simply passes through the conveyance path region where the optical fixing device 8 is located.

  When an image forming pattern that forms only a stereoscopic image is selected, the image forming unit 10H operates to form a thermally foamable toner image T (H) based on the stereoscopic image data as described above. After being transferred to the recording sheet P, fixing is performed by passing at least the light fixing device 8 and irradiating with infrared rays. The fixing may be configured such that the fixing by both the fixing devices 7 and 8 is performed by passing the optical fixing device 8 after passing through the hot-pressure fixing device 7.

  Here, in the case where only the fixing by the optical fixing device 8 is performed, it is necessary to configure so that the hot-pressure fixing device 7 is not passed (not heated and pressurized). As the configuration, for example, a bypass circuit for directly feeding the recording sheet P after transfer to the optical fixing device 8 is formed, or a fixing nip portion of the fixing device 7 is opened (for example, a pressure member is used). It is supported so as to be separated from the heating roll).

  When image formation of this pattern is performed, an IR thermally foamable toner image T (H) is basically formed on the recording sheet P as shown in FIG. As a result, the recording sheet P has a unique concavo-convex surface in which the region where the thermally foamable toner image T (H) is formed is better and more surely raised than the other sheet surface region Pa (convex portion). It is obtained as a recording sheet having (one kind of stereoscopic image). The appearance of the IR heat-expandable toner image after foaming is generally a white appearance color due to light scattering.

  Further, when an image forming pattern formed by combining a color image and a stereoscopic image is selected, at least one of the image forming units 10 (Y, M, C, K) and the image forming unit 10 (H) are selected. By operating as described above, the color toner image T (Y, M, C, K) based on the color image data and the thermally foamable toner image T (H) based on the stereoscopic image data are formed on the recording sheet P, respectively. After the transfer, fixing is performed by passing at least the light fixing device 8 and irradiating with infrared rays. As for the fixing at the time of selecting the image forming pattern, both of them are allowed to pass through the optical fixing device 8 after passing through the hot-pressure fixing device 7 in the same manner as the fixing condition in the case of forming only a stereoscopic image. The fixing devices 7 and 8 may be used for fixing.

  When image formation of this pattern is performed, basically, as shown in FIG. 4, an IR thermal foamable toner image T (H) and a colored toner image T (Y, M, C, At least one of K) is formed in a stacked state in this order. As a result, the recording sheet P has a region (projection) in which the formation region of the IR heat-foamable toner image T (H) on which the colored toner image is formed protrudes better and more reliably than the other region surface Pa. An existing colored stereoscopic image is formed.

  In addition, when the image of this pattern is formed, an IR thermally foamable toner image T (H) is formed on the recording sheet P as shown in FIG. The toner image T (H) may be formed so that the colored toner image T (at least one of Y, M, C, and K) exists in at least a part of the non-formation region of the toner image T (H). As a result, the formation region of the IR heat-foamable toner image T (H) exists as a raised portion (convex portion) on the recording sheet P, while the region where the IR heat-foamable toner image T (H) is not formed. A unique image (an image that appears as if a colored image is formed in a depressed position) in which a colored image (planar image) T (Y, M, C, K) including a colored toner image is present at least partially. Will be formed.

  Further, when the image formation of this pattern is performed, as shown in FIG. 6, it is possible to form a combination of the above two types of image forms, that is, the IR heat on the recording sheet P. The foamable toner image T (H) and the colored toner image T (at least one of Y, M, C, and K) are formed in a stacked state in this order, and the IR thermally foamable toner image T ( The colored toner image T (at least one of Y, M, C, and K) may be formed in at least a part of the non-formation area H). As a result, on the recording sheet P, in addition to the formation of a colored stereoscopic image composed of a colored toner image and an IR heat-foamable toner image, the recording sheet P appears to exist in at least a part of the non-formed area of the colored stereoscopic image A two-dimensional color image is formed.

  Incidentally, when a colored toner image is formed on the IR heat-foamable toner image T (H) and the black toner image T (K) is present in the colored toner image, it is included in the black toner. The carbon black to be absorbed has the property of absorbing infrared rays, so that the infrared rays irradiated by the light fixing device 7 are shielded by the black toner image and hardly reach the IR thermally foamable toner image. As a result, the black toner image The amount of heat generated by the infrared absorbent in the IR heat-foamable toner image in the area where the heat-foaming toner is present may be reduced, and the degree of foaming and swelling of the heat-foamable toner image portion may be reduced.

  However, even in this case, since the black toner image itself generates heat by infrared irradiation, the thermal energy is transmitted to the thermally foamable toner image portion to heat the thermally foamable toner, and the thermally foamable toner It is also possible for the image portion to foam. Therefore, even when a black toner image is formed on the IR thermally foamable toner image T (H), the degree of foaming of the IR thermally foamable toner image is not necessarily sacrificed.

  When forming an IR heat-foamable toner image, when fixing by the optical fixing device 8 after fixing by the fixing device 7, the IR heat-foamable toner image is heated and pressed by the fixing device 7. Since the resin is penetrating between the pulp fibers of the recording sheet P, it is difficult to peel off from the recording sheet even if it starts to foam due to the heating. Then, after such a state (assumed state), since it receives a heating action due to heat generation of the infrared absorber by infrared irradiation, the adhesion of the stereoscopic image composed of the IR thermally foamable toner image to the recording sheet is good. It will be a thing. As a result, a three-dimensional image excellent in strength and durability can be formed.

  In the above-described embodiment, the case where the present invention is applied to a color multifunction device has been described. However, the image forming apparatus of the present invention is not limited to the multifunction device. Of course, the present invention can also be applied to image forming apparatuses such as printers and copiers of various types corresponding to color.

It is explanatory drawing which shows the outline | summary of the color compound machine to which this invention is applied. It is explanatory drawing which shows the structure of an image processing apparatus, and the state of image data generation. It is explanatory drawing which shows the basic aspect which formed only the stereo image. It is explanatory drawing which shows the basic aspect (particularly aspect which overlaps and forms a colored image on a stereo image) formed combining the colored image and the stereo image. It is explanatory drawing which shows the other aspect (particularly the aspect which forms a colored image in at least one part of the non-formation area | region of a stereo image) formed combining the colored image and the stereo image. Description showing another embodiment formed by combining a colored image and a stereoscopic image (particularly an embodiment in which a colored image is superimposed on a stereoscopic image and a colored image is formed in at least a part of a non-formation region of the stereoscopic image) FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Color compound machine (image forming apparatus), 8 ... Light fixing device (irradiation means), 10H ... Image forming unit (first image forming means), 10 (Y, M, C, K) ... Image forming unit (first) 2 (part of image forming means), T (Y, M, C, K)... Colored toner image, T (H). P: Recording sheet (non-thermally foamable recording medium).

Claims (4)

In forming a raised three-dimensional image by forming an image of at least a thermally foamable toner on a non-thermally foamable recording medium and then heating and foaming the thermally foamable toner image,
A heat-foamable toner containing an infrared absorbent is used as the heat-foamable toner, and at least infrared rays are irradiated to a heat-foamable toner image formed with the heat-foamable toner containing the infrared absorbent. Image forming method.   The method according to claim 1, wherein an image made of a non-thermally foamable colored toner is formed in an area where a thermally foamable toner image is not formed. First image forming means for forming an image made of a thermally foamable toner containing an infrared absorbent on a non-thermally foamable recording medium;
An apparatus having irradiation means for irradiating at least infrared rays to the thermally foamable toner image formed by the first image forming means,
An image forming apparatus capable of forming a raised stereoscopic image by heating and foaming a thermally foamable toner image formed on the recording medium.   4. The apparatus according to claim 3, further comprising second image forming means for forming an image made of a non-thermally foamable color toner in an area where a thermally foamable toner image is not formed.