Image forming system

Abstract

To provide an image forming system which can adjust an application amount of varnish in consideration of the permeability of the varnish to a recording material.SOLUTION: An application amount setting table is stored with a basic setting value, a correction value and a varnish application amount setting value. The basic setting value is a varnish application amount which enables formation of the minimum varnish film thickness enabling glossiness to be obtained even if varnish permeates a recording material. The correction value is the varnish application amount corresponding to the varnish film thickness included in image data or varnish film thickness input from an operation unit or the like. The varnish application amount setting value is obtained by adding the basic setting value to the correction value, and in the execution of an image formation job of forming a toner image on the recording material and applying the varnish, the varnish is applied on the basis of the varnish application amount setting value according to the basis weight of the recording material. With this, on the precondition that the minimum varnish film thickness which enables glossiness to be obtained even if the varnish permeates the recording material S is formed, namely the varnish permeates the recording material and the varnish does not permeate any more, the recording material in which the varnish film thickness is adjusted with a correction value is output.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an image forming system including an image forming apparatus that forms a toner image on a recording material, and a varnish application apparatus that applies varnish to the recording material on which the toner image has been formed. [Background technology]

[0002] Recently, an image forming system has been proposed that includes an image forming apparatus that forms a toner image on a recording material and a varnish application device (called a varnish coater) that applies varnish to the recording material on which the toner image has been formed (Patent Document 1). In such an image forming system, applying varnish to the recording material using the varnish coater can improve the glossiness of the toner image compared to when no varnish is applied. Since this glossiness varies depending on the thickness of the varnish layer (also called film thickness) formed on the recording material, the image forming system makes it possible to change the film thickness of the varnish layer by adjusting the amount of varnish applied by the varnish coater. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-224111 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the thickness of the varnish layer formed on the recording material is affected by the permeability of the varnish into the recording material, and if the permeability of the varnish into the recording material is high, the varnish will penetrate deep into the recording material, and in the past, it was not possible to form a varnish layer with the desired thickness on the recording material. Therefore, there has been a long-standing desire for a device that allows the amount of varnish applied by a varnish coater to be adjusted taking into account the permeability of the varnish into the recording material, but such a device has not yet been proposed.

[0005] The present invention has been made in consideration of the above problems, and aims to provide an image forming system that has a varnish coater and that allows the amount of varnish applied by the varnish coater to be adjusted taking into account the permeability of the varnish into the recording material in order to create glossy printed matter. [Means for solving the problem]

[0006] An image forming system according to one embodiment of the present invention comprises an image forming device capable of forming a toner image on a recording material, a varnish application device that applies varnish to the recording material, and a control means that controls the image forming device and the varnish application device to execute an image forming job in which a toner image is formed on the recording material and varnish is applied, wherein the control means applies a first application amount of varnish per unit area to the recording material when executing an image forming job in which a varnish layer is formed on a recording material of a first basis weight, and applies a second application amount of varnish per unit area to the recording material that is greater than the first application amount when executing an image forming job in which a varnish layer is formed on a recording material of a second basis weight that is smaller than the first basis weight.

[0007] An image forming system according to one embodiment of the present invention comprises an image forming device capable of forming a toner image on a recording material, a varnish application device that applies varnish to the recording material, a control means that controls the image forming device and the varnish application device to execute an image forming job that forms a toner image on the recording material and applies varnish, and a detection means that is provided in the image forming device and detects the permeability of the recording material before the toner image is formed, wherein the control means applies a first application amount of varnish per unit area to the recording material when executing an image forming job that forms a varnish layer on a recording material with a first permeability, and applies a second application amount of varnish per unit area that is greater than the first application amount to the recording material when executing an image forming job that forms a varnish layer on a recording material with a second permeability that is smaller than the first permeability. [Effects of the Invention]

[0008] According to the present invention, in order to create glossy printed matter in an image forming system having a varnish application device, the amount of varnish applied by the varnish application device can be adjusted taking into account the penetration of the varnish into the recording material. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing an image forming system according to an embodiment of the present invention. [Figure 2] Schematic diagram showing a varnish coater. [Figure 3] FIG. 2 is a control block diagram of the image forming system. [Figure 4] 10 is a flowchart showing an application amount setting process. [Figure 5] FIG. 10 is a diagram showing an application amount setting table. [Figure 6] 10 is a graph showing the relationship between varnish film thickness and correction value. [Figure 7] 10 is a flowchart showing an image formation control process. [Figure 8] Graph showing the relationship between air volume and air permeability. [Figure 9] 10 is a flowchart showing a registration process. [Figure 10] 10 is a graph showing the relationship between air permeability and the basic setting value. DETAILED DESCRIPTION OF THE INVENTION

[0010] [First embodiment] <Image forming system> The image forming system of this embodiment will be described with reference to the drawings. As shown in Fig. 1, the image forming system 1X of this embodiment has an image forming apparatus 100 that forms a toner image on a recording material S, and a varnish application device (called a varnish coater) 200 that applies varnish to the recording material S on which the toner image has been fixed by the image forming apparatus 100, connected to it. In other words, this image forming system 1X is an inline system that automatically transports the recording material S on which the toner image has been formed from the image forming apparatus 100 to the varnish coater 200, and can consistently process the image formation process and the varnish application process on the recording material S in response to the input of an image formation job.

[0011] The varnish coater 200 is configured to be freely connectable to the image forming apparatus 100 as one of the peripheral devices (also called an optional unit, etc.) that can be added later to expand the functions of the image forming apparatus 100. The varnish coater 200 can apply varnish to the recording material S discharged from the apparatus main body 100A to perform surface treatment, for example, to impart gloss or protect the surface in order to increase the added value of the recording material S. The varnish coater 200 will be described later.

[0012] The image forming apparatus 100 will be described with reference to FIG. 1. The image forming apparatus 100 is a tandem-type electrophotographic full-color printer. The image forming apparatus 100 has image forming units Pa, Pb, Pc, and Pd that form yellow, magenta, cyan, and black images, respectively. The image forming apparatus 100 forms a toner image on a recording material S in accordance with image data from an original reading device (not shown) connected to the apparatus main body 100A or an external device 91, such as a personal computer, connected to the apparatus main body 100A so as to be able to transmit and receive signals.

[0013] In this embodiment, the image forming units Pa to Pd, primary transfer rollers 24a to 24d, intermediate transfer belt 130, multiple rollers 13 to 15, and outer secondary transfer roller 11 constitute an image forming unit 300 that forms a toner image on recording material S. Examples of recording material S include various types of sheet materials such as plain paper, cardboard, rough paper, textured paper, coated paper, plastic film, cloth, etc.

[0014] As shown in FIG. 1, image forming stations Pa, Pb, Pc, and Pd are arranged in line within the apparatus main body 100A along the direction of movement of an intermediate transfer belt 130. The intermediate transfer belt 130 is stretched around multiple rollers (13, 14, and 15) and configured to travel in the direction of arrow R2. The intermediate transfer belt 130 carries and transports the toner image that has been primarily transferred. An outer secondary transfer roller 11 is arranged at a position opposite the inner secondary transfer roller 14 that stretches the intermediate transfer belt 130, sandwiching the intermediate transfer belt 130 therebetween, and forms a secondary transfer nip portion T2 that transfers the toner image on the intermediate transfer belt 130 to a recording material S. A fixing device 8 is arranged downstream of the secondary transfer nip portion T2 in the recording material transport direction.

[0015] A cassette 10 containing a recording material S is disposed at the bottom of the image forming apparatus 100. The recording material S is transported from the cassette 10 toward a registration roller 12 by a transport roller 16. Thereafter, the registration roller 12 starts to rotate in synchronization with the toner image formed on the intermediate transfer belt 130 as described below, and the recording material S is transported to the secondary transfer nip T2. Note that although only one cassette 10 is shown here, a plurality of cassettes 10 may be disposed so as to be able to accommodate recording materials S of different sizes and thicknesses. In this case, the recording material S is selectively transported from one of the plurality of cassettes 10. Furthermore, the recording material S is not limited to that contained in the cassette 10, and recording material S placed on a manual feed unit (not shown) may also be transported.

[0016] The four image forming units Pa, Pb, Pc, and Pd included in the image forming apparatus 100 have substantially the same configuration except for the different developing colors. Therefore, the yellow image forming unit Pa will be described here as a representative, and descriptions of the other image forming units Pb, Pc, and Pd will be omitted.

[0017] The image forming unit Pa is provided with a cylindrical photosensitive drum 3a as a photosensitive member. The photosensitive drum 3a is driven to rotate in the direction of arrow R1. Around the photosensitive drum 3a, a charging device 2a, an exposure device La, a developing device 1a, a primary transfer roller 24a, and a drum cleaning device 4a are arranged.

[0018] The process of forming, for example, a full-color image using the image forming apparatus 100 will be described. First, when the image formation operation begins, the surface of the rotating photosensitive drum 3a is uniformly charged by the charging device 2a. The charging device 2a is, for example, a corona charger that irradiates the photosensitive drum 3a with charged particles due to corona discharge, thereby charging the photosensitive drum 3a to a uniform negative dark potential. Next, the photosensitive drum 3a is scanned and exposed to laser light corresponding to an image signal emitted from the exposure device La. As a result, an electrostatic latent image corresponding to the image signal is formed on the surface of the photosensitive drum 3a. The electrostatic latent image formed on the photosensitive drum 3a is developed into a visible toner image using a developer containing toner and carrier contained in the developing device 1a. In this embodiment, the developing devices 1a to 1d each use a two-component developer containing non-magnetic toner and magnetic carrier. The toner used has a low melting point and contains a binder resin, a colorant, and wax as a release agent.

[0019] The toner image formed on the photosensitive drum 3a is primarily transferred to the intermediate transfer belt 130 at a primary transfer nip T1 formed between the photosensitive drum 3a and a primary transfer roller 24a disposed across the intermediate transfer belt 130. At this time, a primary transfer voltage is applied to the primary transfer roller 24a. Any toner remaining on the surface of the photosensitive drum 3a after the primary transfer is removed by a drum cleaning device 4a.

[0020] This operation is performed sequentially at each of the yellow, magenta, cyan, and black image forming stations Pa to Pd, and the four color toner images are superimposed on the intermediate transfer belt 130. Thereafter, in synchronization with the formation of the toner images, the recording material S stored in the cassette 10 is conveyed to the secondary transfer nip T2. Then, by applying a secondary transfer voltage to the outer secondary transfer roller 11, the full-color toner images formed on the intermediate transfer belt 130 are secondarily transferred all at once onto the recording material S. Any toner remaining on the intermediate transfer belt 130 after the secondary transfer is removed by a belt cleaning device 22.

[0021] The recording material S onto which the toner image has been transferred is then transported to the fixing device 8. In the fixing device 8, the recording material S carrying the toner image is nipped and transported in a fixing nip T3 formed by a fixing roller 40 and a pressure roller 41, where heat and pressure are applied to the recording material S. The toner of the toner image carried on the recording material S is melted and mixed by this heating and pressure, and is fixed onto the recording material S as a full-color image. The recording material S onto which the toner image has been fixed by the fixing device 8 is transported from the image forming apparatus 100 to a varnish coater 200.

[0022] In this embodiment, the interior of the varnish coater 200 is divided into a varnish application route 205, where varnish is applied to the recording material S, and a varnish bypass route 204, where varnish is not applied to the recording material S, and it is possible to switch the transport route of the recording material S to either one. That is, by switching the flapper 206, the recording material S can be transported to the varnish application route 205 when varnish is to be applied, or to the varnish bypass route 204 when varnish is not to be applied.

[0023] <Varnish Coater> Next, the varnish coater 200 will be described with reference to Fig. 2. Fig. 2 shows an example of a roll coater-type varnish coater 200 that uses an ultraviolet-curable UV varnish that hardens with ultraviolet light and is capable of forming a varnish layer over the entire surface of the recording material S. As shown in Fig. 2, the varnish coater 200 includes a varnish application unit 200a and a varnish solidification unit 200b.

[0024] The varnish application unit 200a includes a varnish application roller 211, a counter roller 212, a feed roller 213, a regulating roller 214, and a varnish reservoir 215. The varnish application roller 211, the feed roller 213, and the regulating roller 214 are rotatable by a motor 250. The counter roller 212 contacts the varnish application roller 211 to form a nip that can sandwich and transport the recording material S. The varnish reservoir 215 stores the varnish liquid to be applied to the recording material S. The varnish reservoir 215 is open at the top, and a portion of the outer surface of the feed roller 213 enters through this opening and is immersed in the varnish liquid. Therefore, the feed roller 213 can carry the varnish liquid on its outer surface by rotating. The regulating roller 214 regulates and distributes the varnish on the outer surface of the feed roller 213 evenly so that the varnish carried on the outer surface is transported downstream in the rotational axis direction with the same thickness.

[0025] The varnish reservoir 215 and feed roller 213 are provided so as to be movable together by an actuator 260 between a contact position where the feed roller 213 contacts the surface of the varnish application roller 211 and a separated position where the feed roller 213 is not in contact with the surface of the varnish application roller 211. When the feed roller 213 and varnish reservoir 215 are moved in the direction of arrow F in the figure, the feed roller 213 comes into contact with the surface of the varnish application roller 211. When the feed roller 213 carrying the varnish rotates and reaches the contact position, the varnish is supplied from the feed roller 213 to the varnish application roller 211.

[0026] In the case of such a varnish application unit 200a, the amount of varnish applied per unit area to the recording material S varies depending on the amount of varnish supplied from the feed roller 213 to the varnish application roller 211. The amount of varnish supplied from the feed roller 213 to the varnish application roller 211 is determined by the rotational speed of the feed roller 213 and the contact pressure between the feed roller 213 and the varnish application roller 211. In other words, changing the rotational speed of the feed roller 213 changes the amount of varnish that the feed roller 213 can carry by rotation. Also, changing the contact pressure between the feed roller 213 and the varnish application roller 211 can change the amount of varnish supplied from the feed roller 213 and carried by the varnish application roller 211. The recording material S is nipped and transported between the varnish application roller 211 and the opposing roller 212, and the varnish carried by the varnish application roller 211 is applied to the surface of the recording material S.

[0027] The recording material S, with varnish applied to one side in this manner, is sent from the varnish application unit 200a to the varnish solidifying unit 200b. The varnish solidifying unit 200b has a varnish solidifying section 221 and a sheet conveying section 222. The recording material S is sent by the sheet conveying section 222 to the varnish solidifying section 221, which is downstream in the conveying direction, and the varnish on the recording material S is solidified by the varnish solidifying section 221. The varnish solidifying section 221, which serves as an irradiation section, has an ultraviolet lamp that irradiates UV light of a wavelength corresponding to the varnish to solidify the varnish applied to the recording material S.

[0028] The application unit for applying the varnish to the recording material S is not limited to a roll coater system using a varnish application roller 211 and an opposing roller 212, but may also be an inkjet system using a line head, for example. When a line head is used, not only can the varnish be applied to the entire surface of the recording material S to form a varnish layer, but varnish images such as letters and figures can also be formed at any position on the recording material S. Also, while UV varnish has been used as an example of the varnish, this is not limiting, and oil-based varnish or water-based varnish may also be used. However, when using oil-based or water-based varnish, it is preferable to use an IR (infrared) lamp as a drying unit for drying the varnish rather than an ultraviolet lamp. The varnish may also be dried using warm air, or an IR lamp and warm air may be used in combination.

[0029] <Control configuration of image forming system> Next, the control configuration of the image forming system 1X will be described using Fig. 3 while also referring to Figs. 1 and 2. In this embodiment, an example will be described in which the image forming apparatus 100 (more specifically, the main control unit 101) centrally manages and controls operation commands for the varnish coater 200. Note that various devices other than those shown in Fig. 3, such as motors and power supplies, are also connected, but illustration and description of these are omitted here as they are not the main focus of the invention.

[0030] In the image forming system 1X of this embodiment, as shown in Fig. 3, a varnish application control unit 230 is connected to a main control unit 101 provided in the image forming apparatus 100 via a communication cable 500 so that it can communicate operation commands and various data. The varnish application control unit 230 provided in the varnish coater 200 operates in accordance with operation commands from the main control unit 101. In other words, the main control unit 101 can control the entire image forming system 1X by sending operation commands to the varnish coater 200 while controlling the operation of the image forming apparatus 100.

[0031] The main control unit 101 and the varnish application control unit 230 may have the same configuration, for example, each having a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory).

[0032] The main control unit 101, which serves as control means, has a CPU 102, a ROM 103, and a RAM 104. The ROM 103 and RAM 104 store various programs, such as the application amount adjustment process (see FIG. 4) and image formation control process (see FIG. 7), which will be described later, and various data, such as an application amount setting table (see FIG. 5). The RAM 104 can also temporarily store the results of calculations that accompany the execution of the various programs. The varnish application control unit 231 has a CPU 232, a ROM 233, and a RAM 234. The CPU 232 operates the varnish coater 200 based on the control program stored in the ROM 233.

[0033] The image forming apparatus 100 is equipped with an operation unit 95 (see FIG. 1), which is connected to the main control unit 101. The operation unit 95 has an input unit 95a and a display unit 95b. The input unit 95a, which serves as input means, is, for example, an operation panel, which allows the user to input instructions to execute various programs such as an image forming job, as well as various data. In this embodiment, it is possible to input instructions to execute an image forming job that forms a toner image on a recording material S and applies varnish. The display unit 95b, which serves as display means, is, for example, an LCD monitor, which can display various screens, such as a "varnish application amount correction screen" described below, or a menu screen presenting various executable programs.

[0034] Furthermore, an external device 91 such as a personal computer can be connected to the main control unit 101, and image data, instructions to execute various programs, and various data can be obtained from the external device 91. The operation unit 95 may be a touch panel that displays various screens on the display unit 95b and can accept inputs to start various programs and inputs of various data in response to touch operations on the screen by the user.

[0035] The main control unit 101 is connected to a motor 250 that rotates and drives the above-mentioned varnish application roller 211, feed roller 213, and regulating roller 214, and an actuator 260 that moves the varnish reservoir 215 and feed roller 213 together. As described above, the main control unit 101 controls these motors 250 and actuator 260 to adjust the amount of varnish supplied from the feed roller 213 to the varnish application roller 211, thereby changing the amount of varnish applied per unit area of ​​the recording material S.

[0036] <Application amount setting process> Next, the amount of varnish applied per unit area of ​​the recording material S (g / m 2 4 to 6 with reference to Fig. 1 and Fig. 3. Although not shown, the "application amount setting process" of this embodiment is started by the main control unit 101 in response to, for example, the user operating a print button (not shown) on the initial screen displayed on the display unit 95b.

[0037] In response to the operation of the print button, the main control unit 101 displays a "print setting screen" (not shown) on the display unit 95b, and waits for the user to select a recording material S from the "print setting screen" (S1). If the user performs an operation other than selecting a recording material S, the main control unit 101 may transition the display on the display unit 95b from the "print setting screen" to another screen, such as an initial screen. When the user performs an operation to select a recording material S, the main control unit 101 identifies a "varnish coating setting value" corresponding to the type of recording material S selected from an "application amount setting table" (see FIG. 5) stored in the ROM 103 or RAM 104 serving as storage means (S2).

[0038] <Application amount setting table> An example of the "application amount setting table" is shown in Fig. 5. The "application amount setting table" includes the basis weight (g / m2) of the recording material S corresponding to the above "paper type 1 to paper type 5". 2), air permeability (seconds), and brand names assigned by the user to distinguish between "paper types 1 to 5." In FIG. 5, brands "A to E," in which the air permeability increases as the basis weight increases, are shown as examples. In this specification, the air permeability of the recording material S is expressed as the time (seconds) it takes for a specified volume of air to pass through in the thickness direction of the recording material S.

[0039] The "application amount setting table" stores "varnish coating setting values" for each of "paper types 1 to 5." The "varnish coating setting values" store the varnish type, basic setting value (reference value), correction value (application amount correction value), and varnish application amount setting value. The varnish type is the type of varnish applied to the recording material S by the varnish coater 200, and Figure 5 shows an example in which the same varnish type, "UV varnish," is stored.

[0040] Basic setting value (g / m 2 ) is the amount of varnish applied (lower limit) that can form a minimum varnish film thickness (for example, 100 μm) that will give a glossy appearance even after the varnish has penetrated, assuming that the varnish applied to various recording materials S will penetrate, and is set to a value obtained in advance through experiments, etc. This basic setting value is set to a larger value for recording materials S with a small basis weight (air permeability), such as "paper type 4," compared to recording materials S with a large basis weight (air permeability), such as "paper type 5."

[0041] This is because when the air permeability of the recording material S is, for example, 40,000 seconds (JIS P8117) or higher, the varnish does not easily penetrate into the recording material S. In other words, the greater the air permeability of the recording material S, the lower the permeability of the varnish into the recording material S. In other words, the lower the air permeability of the recording material S, the higher the permeability of the varnish into the recording material S. Therefore, even when the same amount of varnish is applied, a greater amount of varnish penetrates into the recording material S when the varnish is highly permeable than when the varnish is less permeable, resulting in a thinner varnish layer formed on the recording material S than when the varnish is less permeable. Therefore, the minimum amount of varnish applied that can make the thickness of the varnish layer actually formed on the recording material S the same when the varnish is highly permeable (low air permeability) and when the varnish is less permeable (high air permeability), is set to a higher basic value for recording materials S with low air permeability than for recording materials S with high air permeability.

[0042] 5, the basic setting value is set to a larger value for a recording material S having a lower air permeability than for a recording material S having a higher air permeability with an increased basis weight.

[0043] Correction value B is the amount of varnish applied that corresponds to the varnish film thickness contained as information in the received image data (called the initial amount of varnish applied), or the amount of varnish applied that corresponds to the varnish film thickness input from the operation unit 95 or external device 91. By inputting the desired varnish film thickness from the operation unit 95 or external device 91, the user can change the thickness of varnish applied to the recording material S based on the thickness of the varnish formed by the initial amount of varnish applied.

[0044] Figure 6 shows the relationship between the varnish film thickness and the correction value B. As shown in Figure 6, the relationship between the varnish film thickness (μm) and the correction value B (g / m 2) is directly proportional to the varnish thickness, and to increase the varnish thickness, a larger amount of varnish must be applied. According to the relationship shown in Figure 6, the amount of varnish applied corresponding to the varnish thickness can be determined from the varnish thickness information contained in the received image data, or from the varnish thickness input from the operation unit 95 or external device 91. Note that the relationship between the varnish thickness and correction value B shown in Figure 6 is the same regardless of the basis weight of the recording material S, and may differ depending on the type of varnish.

[0045] Returning to Figure 5, the varnish application amount setting value is calculated by the following formula (1), and is the amount of varnish applied per unit area to the recording material S by the varnish coater 200 during an image formation job. In this embodiment, the varnish film thickness is adjusted using correction value B on the assumption that the minimum varnish film thickness is formed to provide a glossy appearance even when the varnish penetrates into the recording material S (basic setting value), in other words, the varnish penetrates into the recording material S but does not penetrate any further. Varnish application amount setting value D = basic setting value A + correction value B Formula (1)

[0046] Returning to FIG. 4, the main control unit 101 determines whether or not the thickness of the varnish to be formed on the recording material S has been input (S3). Whether or not the thickness of the varnish has been input depends on whether or not the thickness of the varnish has been input from the operation unit 95, external device 91, etc. If the thickness of the varnish has not been input (No in S3), the main control unit 101 ends the process. On the other hand, if the thickness of the varnish has been input (Yes in S3), the main control unit 101 calculates the correction value B according to the relationship between the varnish thickness and the correction value B shown in FIG. 6 as described above, and sets this in the "application amount setting table" (see FIG. 5) (S4). The main control unit 101 then calculates the varnish application amount setting value D according to the above-described formula (1), and sets this in the "application amount setting table" (S5).

[0047] <Image formation control process> Next, the "image formation control process" of this embodiment will be described using Fig. 7 with reference to Fig. 1 and Fig. 3. Although not shown, the "image formation control process" shown here is started by main control unit 101 in response to the user operating an image formation start button (not shown) on the initial screen displayed on display unit 95b, for example.

[0048] The main control unit 101 acquires information about the recording material S (such as type and size) input by the user from the operation unit 95 or external device 91 (S11). The main control unit 101 also determines whether the user has issued an instruction to execute an image forming job for forming a toner image on the recording material S and applying varnish from the operation unit 95 or external device 91, or whether "varnish" has been input for the recording material S (S12). If "varnish is not applied" (No in S12), the main control unit 101 selects a normal image forming job (S16) and notifies the varnish coater 200 that a printout without varnish is to be produced (S17). The main control unit 101 then starts the job (normal mode) (S15), causing the image forming apparatus 100 to perform image formation processing while preventing the varnish coater 200 from applying varnish, thereby outputting a printout without a varnish layer on the recording material S.

[0049] On the other hand, if "varnish is applied" (Yes in S12), the main control unit 101 reads out the corresponding "varnish application amount setting value" from the above-mentioned "varnish application amount setting table" (see FIG. 5) according to the input basis weight of the recording material S (S13). The main control unit 101 then sends the fact that the printed material is varnished and the read-out "varnish application amount setting value" to the varnish coater 200 (S14). Thereafter, the main control unit 101 starts the job (varnish application mode) (S15), causes the image forming apparatus 100 to perform image formation processing, and causes the varnish coater 200 to perform varnish application processing, thereby outputting the recording material S with a varnish layer formed thereon as a printed material.

[0050] With reference to FIG. 5, the thickness of the varnish layer formed on the recording material S will be specifically described. Note that, here, the case where the same thickness of varnish layer (for example, 100 + 20 μm) is formed on the recording material S of "paper type 1 to paper type 5" will be described as an example. To do this, as shown in FIG. 5, the correction value B for "paper type 1 to paper type 5" is set to "5 g / m" which corresponds to the same thickness (20 μm). 2 " is set to ".

[0051] In Figure 5, the basic setting value for "Paper type 1 (basis weight 50-105)" is "227" and the correction value is "5", so the varnish application amount setting value is "232". Therefore, for "Paper type 1", a varnish application amount setting value of "232" is applied, resulting in a varnish layer with a thickness of "120 μm". The basic setting value for "Paper type 2" is "136" and the correction value is "5", so the varnish application amount setting value is "141". Therefore, for "Paper type 2 (basis weight 106-128)", a varnish application amount setting value of "141" is applied, resulting in a varnish layer with a thickness of "120 μm". The basic setting value for "Paper type 3 (basis weight 129-150)" is "68" and the correction value is "5", so the varnish application amount setting value is "73". Therefore, for "Paper type 3," a varnish layer with a thickness of "120 μm" is formed by applying varnish with a varnish application amount setting of "73." For "Paper type 4 (basis weight 151-180)," the basic setting is "34" and the correction value is "5," so the varnish application amount setting is "39." For "Paper type 4," a varnish layer with a thickness of "120 μm" is formed by applying varnish with a varnish application amount setting of "39." For "Paper type 5 (basis weight 221-256)," the basic setting is "23" and the correction value is "5," so the varnish application amount setting is "28." For "Paper type 5," a varnish layer with a thickness of "120 μm" is formed by applying varnish with a varnish application amount setting of "28."

[0052] Thus, in this embodiment, when an image forming job is executed in which a toner image is formed on a recording material S and varnish is applied, when forming a varnish layer of the same film thickness, if the recording material S has a first basis weight, a first application amount of varnish per unit area is applied to the recording material S. Then, if the recording material S has a second basis weight that is smaller than the first basis weight, a second application amount of varnish that is larger than the first application amount is applied to the recording material S per unit area.

[0053] As described above, in this embodiment, the varnish application amount is determined using an application amount setting table that stores basic setting values, correction values, and varnish application amount setting values. That is, when an image formation job is executed to form a toner image on a recording material S and apply varnish, the application amount setting table is referenced to read a varnish application amount setting value corresponding to the basis weight of the recording material S, and varnish is applied according to the read varnish application amount setting value. The varnish application amount setting value is the sum of the basic setting value and the correction value, and is the amount of varnish applied per unit area to the recording material S by the varnish coater 200 during the image formation job. In this embodiment, the basic setting value is determined based on the assumption that the minimum varnish film thickness is formed to provide a glossy appearance even if the varnish penetrates the recording material S—in other words, that the varnish penetrates the recording material S but does not penetrate further—and the varnish film thickness is adjusted using the correction value. As a result, the recording material S is output with a varnish film thickness adjusted according to the correction value, based on the assumption that the minimum varnish film thickness is formed to provide a glossy appearance even if the varnish penetrates the recording material S—in other words, that the varnish penetrates the recording material but does not penetrate further. In this way, in this embodiment, in order to create glossy printed matter in the image forming system 1X having the varnish coater 200, the amount of varnish applied by the varnish coater 200 can be adjusted taking into account the permeability of the varnish into the recording material S.

[0054] [Second embodiment] In the above-described embodiment, the varnish is applied in accordance with a varnish application setting value corresponding to the basis weight of the recording material S by referring to the application amount setting table (see FIG. 5), but this is not limiting, and the varnish may be applied in accordance with a varnish application setting value corresponding to the air permeability of the recording material S. This will be explained below.

[0055] 1, in the image forming apparatus 100 of this embodiment, an air permeability detection unit 600 is disposed in front of the registration rollers 12 (upstream in the conveyance direction of the recording material S) in order to measure the air permeability of the recording material S. The air permeability detection unit 600 is provided to measure the air permeability of the recording material S based on the amount of air passing through the recording material S when air is blown from one side to the other side of the recording material S, which is paused at the position of the registration rollers 12.

[0056] The air permeability detection unit 600 as a detection means includes a blower fan 601 capable of blowing air at a predetermined air volume (flow speed) onto the recording material S, and an air volume sensor 602 that detects the volume of air passing through the recording material S. The blower fan 601 and the air volume sensor 602 are disposed opposite each other on the conveyance path of the recording material S, so that the blower fan 601 blows air from one side and the air volume sensor 602 can detect the volume of air passing through the recording material S. The blower fan 601 and the air volume sensor 602 are connected to the main control unit 101 (see FIG. 3), and the main control unit 101 controls the air volume of the blower fan 601. The main control unit 101 also acquires the air volume detected by the air volume sensor 602 and calculates the air permeability of the recording material S based on the acquired air volume.

[0057] The relationship between the air volume detected by the air volume sensor 602 and the air permeability of the recording material S will now be described with reference to FIG. 8. As shown in FIG. 8, the air volume (m / s) and the air permeability are in a negative proportional relationship, and the greater the air volume passing through the recording material S, the smaller the air permeability of the recording material S, meaning that the more easily the varnish penetrates into the recording material S. The main control unit 101 determines the air permeability of the recording material S based on the air volume detected by the air volume sensor 602, in accordance with the relationship between air volume and air permeability shown in FIG. 8. It should be noted that the relationship between air volume and air permeability shown in FIG. 8 may differ depending on the basis weight of the recording material S.

[0058] In this embodiment, as shown in FIG. 5, the "application amount setting table" stores the air permeability of the recording material S corresponding to the above-mentioned "paper type 1 to paper type 5." When executing an image forming job in which a toner image is formed on the recording material S and varnish is applied, the main control unit 101 refers to the "application amount setting table" and applies varnish based on the varnish application amount setting value corresponding to the air permeability of the recording material S. In this embodiment, when executing an image forming job in which a toner image is formed on the recording material S and varnish is applied, when forming varnish layers with the same film thickness, if the recording material S has a first air permeability, a first application amount of varnish is applied to the recording material S per unit area. If the recording material S has a second air permeability that is smaller than the first air permeability, a second application amount of varnish that is larger than the first application amount is applied to the recording material S per unit area.

[0059] In this embodiment, the air permeability of blank recording material S before an image is transferred is actually measured, a varnish application amount setting value corresponding to the measured air permeability of recording material S is read out by referring to an application amount setting table, and varnish is applied according to the read varnish application amount setting value. In this way, rather than applying varnish according to a varnish application setting value corresponding to the basis weight of recording material S, the permeability of the varnish into recording material S can be determined at the appropriate time by detecting the air permeability of recording material S, and a varnish layer of the desired thickness can be more appropriately formed.

[0060] <Registration process> In the first and second embodiments described above, the varnish is applied according to a varnish application amount setting value corresponding to the basis weight and air permeability of the recording material S, referring to the "application amount setting table" (see FIG. 5). Therefore, it is only possible to use the recording material S stored in the "application amount setting table." However, there are cases where a user wants to use a recording material S other than those stored in the "application amount setting table." In view of this, it is preferable to allow the user to add a "varnish coating setting value" for a new recording material S to the "application amount setting table." The "registration process (registration mode)" for achieving this will be described below. FIG. 9 is a flowchart showing the registration process. Although not shown, the "registration process" in this embodiment is started by the main control unit 101 in response to the user operating a registration start button (not shown) on the initial screen displayed on the display unit 95b, for example.

[0061] <Registration setting process> As shown in FIG. 9, the main control unit 101 transports the recording material S to be registered in the "application amount setting table" (see FIG. 5) to the registration rollers 12 in the image forming apparatus 100 and temporarily stops the recording material S (S31). Then, the main control unit 101 detects the air permeability of the recording material S using the air permeability detection unit 600 (S32). That is, the main control unit 101 controls the blower fan 601 to blow air onto the recording material S, which is temporarily stopped at the position of the registration rollers 12, and calculates the air permeability of the recording material S based on the air volume acquired from the air volume sensor 602. At this time, the main control unit 101 calculates the air permeability of the recording material S based on the air volume acquired by the air volume sensor 602, in accordance with the relationship between the air volume and the air permeability shown in FIG. 8, as described above. After calculating the air permeability of the recording material S, the main control unit 101 discharges the recording material S as a blank sheet. Then, the main control unit 101 calculates the basic setting value based on the air permeability of the recording material S (S33). The main control unit 101 determines the basic setting value according to the relationship between the air permeability and the basic setting value shown in FIG.

[0062] Fig. 10 shows the relationship between the air permeability of the recording material S and the basic setting value. As shown in Fig. 10, the air permeability (sec) and the basic setting value (g / m 2) is in a negative proportional relationship, and the greater the air permeability of the recording material S, that is, the easier it is for the varnish to penetrate into the recording material S, the smaller the basic setting value. As mentioned above, the greater the air permeability of the recording material S, the lower the permeability of the varnish into the recording material S. In other words, the lower the air permeability of the recording material S, the higher the permeability of the varnish into the recording material S. Therefore, the basic setting value is larger for recording material S with low air permeability than for recording material S with high air permeability.

[0063] Returning to FIG. 9, the main control unit 101 registers the basic setting value calculated in accordance with the relationship between air permeability and basic setting value shown in FIG. 10 in the "application amount setting table" along with other information related to the recording material S (paper type, basis weight, brand, air permeability, etc.). Furthermore, the main control unit 101 sets the correction value to "0" and registers the varnish application amount setting value calculated from the above-mentioned formula (1) in the "application amount setting table" (S34). At this time, the "application amount setting table" as shown in FIG. 5, including the newly registered recording material S, may be displayed on the display unit 95b, and the main control unit 101 may complete the registration when the user operates a registration button (not shown). The basic setting value of the varnish coating registered in the "application amount setting table" may be changed by the user via the operation unit 95. The air permeability of the recording material S corresponding to the basic setting value registered in the "application amount setting table" may also be changed by the user via the operation unit 95. Furthermore, the user may be able to input the air permeability of the recording material S to be registered in the "application amount setting table" from the operation unit 95 as appropriate.

[0064] In the example shown in FIG. 10, when the air permeability is "1000 or less," the basic setting value is "0." The recording material S with a basic setting value of "0" is difficult to apply varnish to due to its permeability, for example, when the basis weight is "50 g / m 2 Since the recording material S is a plain paper smaller than the "coating amount setting table", such recording material S is not registered in the "coating amount setting table".

[0065] As described above, in this embodiment, it is possible to newly register recording materials S in the "application amount setting table." This makes it possible to set the amount of varnish applied based on the basis weight and air permeability of the recording material, even for recording materials S for which it was previously not possible to set the amount of varnish applied. This is therefore preferable because it makes it possible to print in a varnish application mode in which varnish is applied to recording materials S that previously could only be printed in a normal mode. [Explanation of symbols]

[0066] 1X...image forming system, 95a...input means (input section), 95b...display means (display section), 100...image forming apparatus, 101...control means (main control section), 103...storage means (ROM), 104...storage means (RAM), 200...varnish application device (varnish coater), 211...application section (varnish application roller), 212...application section (opposing roller), 221...irradiation section (varnish hardening section), 600...detection means (air permeability detection section), S...recording material

Claims

1. an image forming apparatus capable of forming a toner image on a recording material; a varnish application device that applies varnish to the recording material; a control unit that controls the image forming device and the varnish application device to execute an image forming job of forming a toner image on a recording material and applying varnish; the control means applies a first application amount of varnish per unit area to the recording material when executing an image forming job to form a varnish layer on a recording material of a first basis weight, and applies a second application amount of varnish per unit area to the recording material that is larger than the first application amount when executing an image forming job to form a varnish layer on a recording material of a second basis weight that is smaller than the first basis weight. An image forming system comprising:

2. The control means applies a first application amount of varnish per unit area to the recording material when executing an image forming job to form a varnish layer on a recording material having a first air permeability, when executing an image forming job for forming a varnish layer on a recording material having a second permeability that is equal in basis weight to the recording material of the first permeability and smaller than the first permeability, applying a second application amount of varnish per unit area that is greater than the first application amount to the recording material; 2. The image forming system according to claim 1.

3. a storage means for storing a reference value of the amount of varnish to be applied for each type of recording material; an input unit for inputting an application amount correction value for adjusting the application amount of varnish to be applied to the recording material when the image forming job is executed by correcting a reference value for the application amount of varnish stored in advance; 2. The image forming system according to claim 1.

4. A detection means provided in the image forming apparatus for detecting the air permeability of the recording material before a toner image is formed; a storage means for storing a reference value of the amount of varnish to be applied for each type of recording material; The control means can execute a registration mode in which the detection means detects the air permeability of the recording material in the image forming apparatus, and a reference value corresponding to the detected air permeability is set in the storage means based on a preset relationship between the air permeability of the recording material and a reference value for the amount of varnish applied.

3. The image forming system according to claim 2.

5. A display means is provided, When the registration mode is executed, the control means displays on the display means the type of recording material corresponding to the air permeability detected in the registration mode and the reference value set in the registration mode.

5. The image forming system according to claim 4.

6. an input means for inputting the air permeability of the recording material to be stored in the storage means; 5. The image forming system according to claim 4.

7. The varnish is an ultraviolet curable varnish, The varnish application device has an application unit that applies varnish to the recording material and an irradiation unit that irradiates ultraviolet light onto the varnish applied to the recording material.

2. The image forming system according to claim 1.

8. An image forming apparatus capable of forming a toner image on a recording material; a varnish application device that applies varnish to the recording material; a control unit capable of controlling the image forming apparatus and the varnish applying device to execute an image forming job for forming a toner image on the recording material and applying varnish; a detection means provided in the image forming apparatus for detecting the air permeability of the recording material before a toner image is formed; the control means applies a first application amount of varnish per unit area to the recording material when executing an image forming job to form a varnish layer on a recording material with a first air permeability, and applies a second application amount of varnish per unit area to the recording material that is larger than the first application amount when executing an image forming job to form a varnish layer on a recording material with a second air permeability that is smaller than the first air permeability. An image forming system comprising:

Images