JP2012011626A - Glossing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glossing device that can prevent deterioration of gloss.SOLUTION: The glossing device is configured such that a heater 6 has a plurality of heat generating elements arranged on a substrate, a heated region can be controlled to a sheet P, and an adhesion force between a film substrate of a transfer film 8 and a coating film formed on the film substrate and contacting with the sheet P is 10 or more N/cm, wherein a contact surface of a separation member 11 with the transfer film 8 is formed in an approximately circular surface with a 0.5-3.0 mm of a curvature surface, and a tensile force for reeling the transfer film 8 by a winding mechanism 12 is made to be 2-170 gf/cm.

Description

  The present invention relates to a gloss processing apparatus.

  After forming an image with a thermoplastic resin on the recording material (sheet), the surface is heated again through a transfer film (hereinafter referred to as film), and then cooled to give the image on the recording material gloss, A technique for matting an image is known (Patent Document 1).

JP 2004-170548 A

By the way, the present applicant has proposed a technique for performing gloss processing (or mat processing) on an arbitrary area of the recording material in order to give further expression to the image on the recording material. Specifically, a gloss applying device having a very thin heat-resistant film and a thermal head having a heating element group with a density of about 300 dpi (or higher density) in contact with one surface of the film is used. Technology. The surface of the image formed with the thermoplastic resin (or the image covered with the thermoplastic resin) is brought into contact with the surface of the film opposite to the surface on which the thermal head comes into contact with the surface, and the thermal head is passed through the film. Heat partially. Then, it cools in the state which contacted the film, and isolate | separates a film from an image after that. In the heated image area, the surface property of the film is transferred and the glossiness is improved (in the case of a film having a matte surface, the glossiness is lowered). However, by selectively heating the heating element group of the thermal head, Various glossy expressions can be given.
However, in order to perform such partial gloss processing, it is necessary to give the image the effects of the heat generating element that generates heat and the heat generating element that does not generate heat as faithfully as possible. For this reason, it is necessary to use a very thin film. In addition, it is necessary to provide a coat layer on the surface of the film that comes into contact with the image in order to ensure releasability from the thermoplastic resin. However, as described above, when a coat layer is provided on a very thin film, the coat layer formed on the film surface in order to separate the image and the film satisfactorily peels off from the film substrate at the separation part, It may be transferred to the surface. In the portion where the coat layer has been transferred, a gloss failure that reduces the gloss of the image occurs. This is because the surface energy of the coat layer formed in order to ensure releasability with the thermoplastic resin is low, resulting in a decrease in the adhesive force between the coat layer and the film substrate. Conceivable.
Further, if the releasability between the thermoplastic resin and the coating layer cannot be ensured, the film and the image may not be separated at the normal position and may be shifted in the paper discharge direction. Usually, a separation plate is present when separating the film and the image, and the separation is performed at a uniform position in the longitudinal direction in order to separate the film along the separation plate. However, if the separation position is shifted in the paper discharge direction and separation is attempted at a position where the separation plate does not exist, the film has low rigidity, so the film bends in the longitudinal direction, and the tension is not uniformly applied in the longitudinal direction. Separation may be delayed. As a result, the force concentrates on the part where the separation is delayed in the longitudinal direction, and a part of the image surface such as WAX on the recording material is transferred to the film side at the part, and the image surface becomes rough and the gloss is lowered. Arise.
Further, when the separation position between the film and the image further shifts in the paper discharge direction, the film and the image may enter the pair of sheet feeding rollers without being separated, and a paper discharge failure may occur.

An object of the present invention is to provide a gloss processing apparatus that can suppress poor gloss.

In order to achieve the above object, a gloss processing apparatus of the present invention comprises a heater, a transfer film slidable on the heater, a pressure member provided on the opposite side of the heater with respect to the transfer film, A sheet on which an image is formed is moved relative to the heater together with the transfer film at a nip portion between the transfer film and the pressure member, and the sheet is moved toward the image forming surface side of the sheet. It is an apparatus that performs gloss treatment by transferring the surface shape of the transfer film by heating and pressurizing the supported thermoplastic resin material,
A winding means for winding the transfer film, and a surface of the transfer film that contacts the surface of the transfer film opposite to the contact surface with the sheet, and the transfer film wound by the winding means has a surface shape of the transfer film. A separating member for separating from the transferred sheet,
The heater has a plurality of heating elements arranged on a substrate, and is configured to be able to control a heating area to the sheet, and is formed on the film base of the transfer film and the film base. In the gloss processing apparatus having an adhesive force of 10 N / cm ² or more with the contacting coating layer, the contact surface of the separation member with the transfer film is a substantially arc surface with a radius of curvature of 0.5 mm to 3.0 mm. While forming, the tension | tensile_strength which winds up the said transfer film by the said winding-up means shall be 2 gf / cm or more and 170 gf / cm or less.

  As described above, according to the present invention, poor gloss can be suppressed.

Sectional drawing which shows schematic structure of the gloss processing apparatus of embodiment. Schematic sectional view showing the configuration of the main part of the gloss processing device Schematic sectional view showing the configuration of the main part of the gloss processing device Schematic explaining the structure of the heating element of the thermal head The figure which shows schematic structure of the drive circuit of a thermal head Schematic diagram of an apparatus for measuring adhesive strength Schematic showing how the gloss level has decreased Schematic cross section showing how the image surface is rough Schematic of how the film and recording material entered the sheet feed roller without separation

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. .

[Entire device configuration]
FIG. 1 is a cross-sectional view showing a schematic configuration of the gloss processing apparatus of the present embodiment. The gloss processing apparatus of the present embodiment softens the thermoplastic resin (on the sheet) carried on the sheet (processing medium) by heating and deforms it using the surface shape of the transfer film, so that the surface of the transfer film The gloss is processed by transferring the shape. First, the overall configuration of the gloss processing apparatus will be described.
In FIG. 1, reference numeral 1 denotes an apparatus main body, 2 a cassette on which sheets (recording materials) P are stacked, and 3 a feeding roller for separating and feeding the sheets P from the cassette 2 one by one. Reference numeral 4 denotes a pair of sheet feed rollers that sandwich the sheet P fed from the feed roller 3 and convey the sheet P toward the processing unit (heating unit, nip unit). The sheet feed roller pair 4 is configured to reciprocate the sheet P. A sensor 14 detects the leading edge of the sheet P when the sheet P is conveyed in advance to the recording start position of P1.
Reference numeral 5 denotes a platen roller as a pressure member disposed across the sheet conveyance path, and 6 denotes a thermal head as a heater that selectively generates heat in accordance with recording information (surface treatment information). The platen roller 5 and the thermal head 6 are arranged facing each other.
Reference numeral 8 denotes a transfer film (hereinafter referred to as a film) that is pressed against the sheet P by the thermal head 6 and is selectively heated. Reference numeral 7 denotes a film cassette (storage portion, mounting portion) in which the film 8 is stored. Reference numerals 12 and 13 denote a film take-up shaft and a film supply shaft for the film 8 provided in the film cassette 7, respectively. Reference numeral 11 denotes a separating member that separates the film 8 and the sheet P that are heated and pressed by the thermal head 6. Reference numeral 9 denotes a discharge roller pair for discharging the sheet P out of the apparatus main body, and reference numeral 15 denotes a discharge tray.

(Thermal head)
The basic configuration and basic specifications of the thermal head 6 will be described below. FIG. 4 is a schematic diagram for explaining the configuration of the heating element of the thermal head 6. In the thermal head 6, a common electrode 23a and a lead (individual) electrode 23b are formed on a glaze (hereinafter referred to as a heat insulating layer) 22 printed on a substrate 21 using alumina or the like via a heating element 25. It is constituted by. (The heating element 25 is formed on the lower surface of each electrode.) Further, a protective film (overcoat layer) 24 is formed on the upper surface of the substrate 21, the heat retaining layer 22, the electrodes 23 a and 23 b, and the heating element 25. ing. The thermal head 6 includes a driving circuit for selectively applying electric power to the heating element 25 to generate heat, and a component such as a heat radiating plate for radiating excess heat after the sheet P is heated. It is configured. Here, the gloss processing apparatus of the present embodiment is provided with control means for controlling the amount of heat generated by the heating element 25 using this drive circuit.
In this embodiment, the thermal head 6 having a heating element density of 300 dpi (dots per inch), a recording density of 300 dpi, a driving voltage of 30 V, and a heating element average resistance value of 5000Ω is used. However, the head configuration and specifications of the thermal head 6 are not limited to this.

FIG. 5 is a diagram showing a schematic configuration of a drive circuit of the thermal head 6.
A plurality of heating elements 25 are arranged on the substrate 21 so as to form one line, and electrodes are wired on both sides thereof. A driver IC including a register group for transferring and holding data for one line is provided on the same substrate or on a separate wiring substrate.
The thermal head 6 configured as described above is configured such that the heat generation amount of the plurality of heating elements 25 can be independently adjusted, and the heating area to the sheet P can be controlled. Thus, an intermediate gloss process can be performed on the surface of the sheet P, and a gloss process can be partially performed on the surface of the sheet P. Here, the thermal head 6 is configured to be able to heat a part of the region where the film 8 passes through the nip portion N together with the sheet P, so that a part of the region on the sheet P can be heated. Gloss processing is possible.

(Platen roller)
The platen roller 5 is formed by forming a member having a high coefficient of friction such as hard rubber in the form of a roller. For example, the platen roller 5 is made of a rubber roller using silicon rubber or the like, and is rotatably attached to the apparatus main body 1 by a shaft 5a. The platen roller 5 is configured to transport the film 8 by being driven by a drive source (not shown). The platen roller 5 is provided on the opposite side of the thermal head 6 with respect to the film 8.

(the film)
The film 8 is slidably provided on the thermal head 6 and has a surface shape for performing a gloss treatment on the sheet P having a thermoplastic resin material on the surface (image forming surface side). . Further, the film 8 is wound and stored on the film supply shaft 13 by a desired length, and is supplied to a processing unit including the thermal head 6 by being wound by the film winding shaft 12 as necessary. In the case where the film 8 has a replaceable specification in the gloss processing apparatus, the film 8 is detachably attached to the gloss processing apparatus main body.
The film 8 is made of a thin flexible material in order to locally heat the sheet surface. From this viewpoint, the thickness of the film 8 is desirably 40 μm or less. From the viewpoint of gloss treatment, a thickness of 2 μm is possible, but from the viewpoint of film strength, 4 μm or more is preferable. Furthermore, it is effective that the film has a certain degree of rigidity in order to obtain a surface property with excellent photographic image clarity in the gloss treatment. In the following materials, 8 μm or more is preferable. In addition, the material must be heat resistant to the thermal head. A material having heat resistance exceeding 200 degrees, such as PI (polyimide), is preferable, but a general resin film such as PET (polyethylene terephthalate) can also be used although the heating history remains. As a specific transfer film, a PET film + release coating and a film member having a thickness of 8 μm were used.
A release coating is applied to the film surface layer (the surface in contact with the sheet P). This functional layer is a low surface energy coat layer, and is applied to improve the mold releasability between the film 8 and the thermoplastic resin material on the surface of the sheet P. When the surface shape of the film 8 is transferred, the film 8 and the sheet P can be smoothly released (separated and separated) from the viewpoint of how accurately the shape of the film 8 is transferred to the sheet P. desirable. As these compositions, for example, a fluororesin or a silicone resin can be used. In this example, the base film is formed by coating in order to create a smooth surface for photography. Moreover, the contact angle with respect to the water of the same surface layer is 90 degree | times, and it has the outstanding mold release performance. The surface layer preferably has a contact angle (with respect to water) of 80 degrees or more in order to maintain the release performance.

In the present invention, the adhesive force between the release coating layer formed on the surface layer of the film and the film substrate is important. The measuring method of the adhesive force of a coat layer and a film base material is described below.
FIG. 6 shows a schematic diagram of the measuring apparatus. First, the film 8 is fixed to the flat surface 30 so that the release coat layer becomes the surface. A cylindrical probe 31 having a diameter of 7 mm is fixed on the surface of the fixed film 8 on which the release coating layer is formed, with an adhesive so that the circular surface is in contact with the coating layer. The probe 31 is preferably made of a metal that is small in deformation even when a force is applied. Thereafter, the force gauge 32 is fixed to the cylindrical probe 31 and pulled perpendicularly to the plane on which the film 8 is fixed at a speed of 400 mm / min. Then, the force applied to the force gauge 32 when the coat layer was peeled off was measured and used as the adhesive force between the coat layer and the film substrate.
In order to reduce mechanical friction with the thermal head 6, a stick prevention layer is provided on the back surface of the film (the surface that slides with the thermal head 6). Since characteristics close to those of the release coating described above are required, specifically, coating with a fluororesin or other silicone resin similar to the release layer is effective.
Since the film in the present invention transfers its surface shape, it can be processed into a glossy surface having a high gloss photographic tone if it is a high gloss smooth film. Conversely, if a mat film by sandblasting is used or a film having a specific shape is used, the inverted shape of the shape can be transferred to the sheet P. For example, it is possible to transfer various texture shapes such as those in silk, Japanese paper, and embossed paper. In addition, a geometric pattern can be applied, and various textures such as a lattice can be transferred. Further, it is possible to transfer a surface exhibiting a hologram color by creating a geometric structure of the order of 1 μm to sub μm.
In the present invention, since the surface of the sheet P can be partially glossed, a plurality of these films can be provided, and various shapes and hologram colors can be processed only at necessary places.

(Separation member)
The separating member 11 will be described in detail below.
The separating member 11 has two roles of a film cooling function and a film separating function by curvature. The separation member 11 is made of a metal such as SUS (stainless steel), and is configured to reliably release the sheet P and the film 8 by setting the separation curvature to a sufficiently small value. Here, the separation member 11 contacts the surface of the film 8 opposite to the contact surface with the sheet P and changes the moving direction of the film 8 to separate the film 8 and the sheet P from each other. Although not shown, it is desirable to have a cooling mechanism for suppressing the temperature rise of the separating member 11. For this purpose, it is effective to attach air cooling or cooling fins, for example.
Further, by monitoring the temperature of the separation member 11 with thermistor resistors provided at a plurality of locations, the fan and the printing operation may be controlled so that the temperature of the separation member 11 is equal to or lower than the cooling target temperature T1 ° C.
The cooling target temperature T1 is desirably adjusted to the Tg (glass transition point) of the surface layer resin such as the color material or the overcoat material on the sheet P. Considering the difference between Tg and the melting start point, the cooling target temperature T1 is preferably set to about Tg + 15 degrees, more preferably Tg or less. The color material layer also includes a surface layer material containing components such as Wax in addition to the resin and the colorant. In this case, it is preferable to set it below the melting point of Wax. If the recording material cannot be determined, it is preferable to set the temperature to a sufficiently low temperature of about room temperature. For example, about 30-50 degreeC is favorable.

(Sheet (cut paper))
In this embodiment, a recording material (printed material) output by an electrophotographic recording apparatus (electrophotographic image forming apparatus) is used as a sheet (material to be processed). As the recording material, art paper for printing (basis weight 157 g / m ² ) was used. In this embodiment, there are two types of recording materials, a recording image formed by a four-color toner (thermoplastic resin material) of CMYK and a recording material image-formed by a five-color process including a transparent toner mainly composed of a thermoplastic resin not including a coloring material. Using. For the transparent toner, after separation into CMYK, the transparent toner was supplemented to the portion with a low printing rate, and a printing pattern was determined and output so as to cover the entire recording material with the toner. As a result, it is possible to perform a gloss process on an arbitrary place of the recording material. Further, the toner fixing state in the electrophotographic recording apparatus was adjusted so that the gloss of the recording material by electrophotographic recording was about 10% at 60 ° gloss.
Further, in the present embodiment, the recording material is not limited to the above four-color and five-color processes, but also when the image is formed by a four-color process on a sheet coated with a thermoplastic resin material, Processing is possible. The same applies to sheets recorded by melt thermal transfer recording, sublimation thermal transfer recording, ink jet recording, and the like. Even in this case, by covering the sheet surface with the thermoplastic resin material, it is possible to perform the gloss treatment at an arbitrary position on the entire sheet surface.
As described above, in the sheet carrying the thermoplastic resin material according to the present embodiment, when the material for forming an image on the sheet is a thermoplastic resin material, the thermoplastic resin material is provided on the image forming surface. Including the case of coating.

[Description of operation]
In the apparatus main body 1 shown in FIG. 1, when the sheet P on which an image is recorded is separated and fed one by one from the cassette 2 by the feeding roller 3, the sheet P is directed to the processing unit by the sheet feeding roller pair 4. It is nipped and conveyed. When the sheet P is conveyed in advance to the processing start position of P1, the length of the sheet P is measured by counting the time that passes through the sensor 14 that detects the leading edge of the sheet P.
The sheet P is stopped once when it completely passes through the sensor 14, and is then conveyed by the roller pair 4 in the direction opposite to the previous conveying direction. In the processing unit, the platen roller 5 and the thermal head 6 are arranged to face each other with the sheet conveyance path interposed therebetween (via the film 8), so that a nip portion N is formed between the film 8 and the platen roller 5. Has been. In a state in which the film 8 is positioned on the sheet P (the sheet P and the film 8 are overlaid), the sheet P and the film 8 are relative to the thermal head while being heated and pressurized in the nip portion N. Move on. Here, when the film 8 is positioned on the sheet P, the image forming surface of the sheet P is in contact with the film 8.
Further, while the film 8 and the sheet P moving together with the film 8 are pressed at the nip portion N, each heating element of the thermal head 6 is selectively heated based on the gloss information for the gloss processing. Further, when the recording is started, the film winding unit 12 and the platen roller 5 are driven in synchronization, so that the film 8 can be conveyed by a desired length. Thereafter, the film 8 and the sheet P are separated by the separating member 11, whereby a desired gloss treatment is performed on the sheet P.

In the present embodiment, the tension applied to the film 8 when the film 8 is wound is important. The diameter of the film take-up shaft 12 and the film 8 taken up increases with the thickness of the film 8 every time the used film 8 is taken up. Therefore, in order to obtain a stable film winding tension, the film tension is controlled by the torque of the winding motor, and the torque of the motor is adjusted in consideration of the increase in diameter due to the winding shaft 12 and the wound film 8. It is desirable to control.
The film 8 is wound up by the length of the sheet P, and after the printing (gloss processing) is finished, the platen roller 5 is separated from the thermal head 6.
The glossy-recorded sheet P is nipped and conveyed in the order of the sheet feed roller pair 4 and the paper discharge roller pair 9, and is finally discharged out of the casing, thus completing the recording. Note that roll paper can also be used as the sheet P.
In the present embodiment, the sheet feeding roller pair 4 allows the gloss processing to be performed a plurality of times while reciprocating the sheet P. However, the present invention is not limited to such a configuration. For example, it is possible to use a platen drum and perform the glossing process while rotating the drum a plurality of times. Further, the platen roller can be directly driven to perform the gloss processing only once in one direction.
When the thermal head 6 is energized, the pulse width or number of energization pulses supplied to the heating element 25 is finely controlled according to the signal level of the gloss processing (recorded image). The recording order is line printing for each line, and when printing for one line is completed, the platen roller 5 is rotated by one line to move the sheet P, and the film 8 is also moved by the same amount.
The energization method for the thermal head 6 can be divided into a method for controlling the energization pulse width with a constant number of pulses and a method for controlling the number of pulses by preparing a constant pulse width train for the input signal gradation. . The former can design a fine gradation-density characteristic, but on the other hand, the halftone control unit becomes complicated. In the latter case, it is only necessary to prepare a fixed pulse train and reassign the input gradations, and the burden of the halftone control unit is light.However, in order to achieve precise density characteristics, a considerably larger number of pulses than the actual number of gradations is required. It is necessary to prepare.

[Evaluation methods]
As an evaluation image, a Bk solid image was printed on A3 size recording paper, and then processed with gloss data of a solid image having a width of 19 cm and a length of 35 cm by a gloss processing apparatus.
(A) Film coat layer peeling FIG. 7 shows the state of an image in which the coat layer peeling occurred. In the part where the coating layer peeling of the film 8 occurs, the peeling coating layer adheres to the sheet P, and the glossiness of the output portion decreases. Whether or not the peeled coat layer adhered to the surface of the sheet P was observed with a microscope and evaluated according to the following criteria.
○: Coat layer is not attached to the surface of the sheet P ×: Coat layer is attached to the surface of the sheet P (a) Poor glossiness FIG. If the image continues to be output while the separation position is shifted in the paper discharge direction, an output product in which the entire surface of the image is rough and gloss is reduced is obtained. The decrease in glossiness was evaluated by a 60 degree gloss measured by a trigloss meter (BYK Gartner).
In this example, in order to evaluate a photo-like high gloss surface, evaluation was performed according to the following criteria.
○: No gloss failure occurs in the entire image, and the 60 ° gloss is 80% or more. Δ: The image has a region where the 60 ° gloss is 80% or less. ×: The film 8 and the sheet P are not separated. (Cannot be evaluated)
(C) Discharge failure during continuous processing 50 evaluation images were output, and at that time, during processing, the film 8 and the image were not separated and entered the pair of sheet feed rollers 4 and discharged. The following criteria were used to evaluate whether there were any defects.
○: No paper discharge failure occurs on all 50 sheets ×: Paper discharge failure occurs on one or more of the 50 sheets

[Description of mechanism of this embodiment]
In the present embodiment in which the shape of the surface of the film 8 is transferred, it is desirable to release the mold smoothly from the viewpoint of accurately transferring the shape of the film 8. The film 8 used in the present embodiment is provided with a low surface energy coat layer in order to improve the releasability of the film substrate and the sheet P surface layer resin. However, since the surface energy of the coat layer is low, the adhesive force with the film substrate may be reduced. If the adhesive force between the film substrate and the coating layer is small, the coating layer is peeled off from the film substrate only by bending the film 8 slightly, and the coating layer is transferred onto the surface of the sheet P.
The peeling of the film coat layer is closely related not only to the adhesive force between the coat layer and the substrate but also to the force applied to the surface of the coat layer.
In the present embodiment, in order to locally heat the surface of the sheet P through the film 8 by the thermal head 6, it is necessary to use a very thin film 8. When the film 8 is very thin, the rigidity of the film base material is lowered, so that the film base material is easily stretched by tension. On the other hand, since the coating layer provided in order to improve the release property of the surface layer resin is different from the material of the film substrate, the expansion / contraction rate due to the tension is different from that of the film substrate. Therefore, for example, when the film 8 is greatly bent or when a large tension is applied to the film 8, the film base material is locally stretched and cracks are generated on the surface of the coating layer that could not cope with the stretching. There is a case. That is, it is considered that the relationship between the adhesive force between the film substrate and the coating layer, the tension for winding the film 8, and the curvature radius of the substantially arc surface of the separating member 11 is greatly related to the peeling of the coating layer.

Therefore, in this embodiment, the improvement was made by paying attention to the adhesive force between the film base and the coating layer, the tension for winding the film 8, and the radius of curvature of the separation member 11. As a result of intensive studies by the present inventors, the following conditions have been found as conditions under which gloss failure due to peeling of the coating layer from the film substrate can be suppressed and a better output result can be obtained. That is, the adhesive force between the film substrate and the coating layer is 10 N / cm ² or more, the tension applied to the film 8 is ² gf / cm or more and 170 gf / cm or less, and the curvature radius of the separation member 11 is 0.5 mm or more and 3.0 mm or less. It is. Although not particularly shown in a comparative example described later, when the radius of curvature of the separating member 11 is larger than 3.0 mm, for example, 4.0 mm, the gloss failure cannot be suppressed. On the other hand, when the adhesive force between the film substrate and the coat layer was less than 10 N / cm ² , the coat layer peeled off because the adhesive force between the film substrate and the coat layer was small. When the tension applied to the film 8 is greater than 170 gf / cm or the radius of curvature of the separating member 11 is less than 0.5 mm, the surface of the coat layer that could not cope with the elongation of the film 8 is cracked, and from there The coat layer has come off. On the other hand, when the tension applied to the film 8 is less than 2 gf / cm or the radius of curvature of the separating member 11 is greater than 3.0 mm, the separating member 11 does not sufficiently apply the force for separating the film 8 and the sheet P, and the film 8 and sheet P could not be released.

  Further, if the releasability between the film 8 and the sheet P cannot be ensured, the image separation between the film 8 and the image (formed on the sheet P) is not performed at a normal position, and the sheet 8 shifts in the paper discharge direction. There is a case. If the separation position is shifted in the paper discharge direction and separation is attempted at a position where the separation member 11 is not present, the rigidity of the film 8 is low, so that the film 8 bends in the longitudinal direction, and no uniform tension is applied to the longitudinal direction. Separation is delayed in some parts. As a result, the force concentrates on the portion where the separation is delayed in the longitudinal direction, and a part of the image surface such as WAX on the sheet P is transferred to the film 8 side at that portion, and the image surface becomes rough and the gloss is lowered. Therefore, it is considered that the gloss failure caused by the separation position is largely related to the force for separating the film 8 and the sheet P by the separation member 11, that is, the relationship between the tension for winding the film 8 and the curvature radius of the separation member 11. It is done.

  Therefore, in the present invention, further improvements have been made by paying attention to the tension for winding the film 8 and the radius of curvature of the separating member 11. As a result of intensive studies by the present inventors, if the tension applied to the film 8 is 15 gf / cm or more and 170 gf / cm or less and the radius of curvature of the separating member 11 is 0.5 mm or more and 2.0 mm or less, the film 8 and the image It has been found that the separation position can be prevented from shifting in the paper discharge direction. Thereby, a better output result can be obtained. On the other hand, when the tension applied to the film 8 is less than 15 gf / cm or the radius of curvature of the separating member 11 is greater than 2 mm, the separation position between the film 8 and the image is shifted in the paper discharge direction, resulting in poor gloss.

When the separation angle θ between the film 8 and the sheet P at the separation position is 90 degrees or less, the direction in which the film 8 is wound and the direction in which the sheet P is conveyed are the same direction (for example, in FIG. (The left and right sides of the figure are left-facing). For this reason, even when the force for separating the film 8 and the image is sufficiently applied by the separating member 11, the film 8 and the image may not pass through the normal separation position C as shown in FIG. . If the film 8 and the image are not separated from each other and enter the sheet feed roller pair 4, the film 8 is wound around the sheet feed roller 4, and a discharge failure occurs.
Therefore, in this embodiment, by setting the separation angle between the film 8 and the sheet P to 90 degrees or more, the direction in which the film 8 is wound and the direction in which the sheet P is conveyed are opposite to each other. The separation position can be further suppressed from shifting in the paper discharge direction. For example, as shown in FIG. 2, the film 8 is wound rightward (pulled) on the left and right sides of the drawing, and the sheet P is conveyed leftward. Accordingly, it is possible to suppress a paper discharge failure caused by the film 8 entering the sheet feeding roller 4 without being separated from the image, and a better output result can be obtained.

[Each Example, Comparative Example and Evaluation Results]
Table 1 shows examples, comparative examples, and evaluation results thereof according to the present invention.

Example 1
In this example, as the film 8, a film having an adhesive force of 10 N / cm ² between the film substrate and the coating layer formed on the film surface was used. Further, the apparatus configuration as shown in FIG. 3 was taken, with the tension for winding the film being 2 gf / cm, the radius of curvature of the separating member 11 being 3 mm, and the separating angle of the film 8 and the sheet P being 70 degrees.
(Example 2)
In this example, as the film 8, a film 8 having an adhesive force of 10 N / cm ² between a film base and a coating layer formed on the film surface was used. Further, the apparatus configuration as shown in FIG. 3 was taken, with the tension for winding the film 8 being 170 gf / cm, the radius of curvature of the separating member 11 being 0.5 mm, and the separating angle of the film 8 and the sheet P being 70 degrees.
(Example 3)
In this example, a film 8 having an adhesive force of 15 N / cm ² between the film substrate and the coating layer formed on the film surface was used as the film 8. Further, the apparatus configuration as shown in FIG. 3 was adopted with the tension for winding the film 8 being 15 gf / cm, the radius of curvature of the separation member 11 being 2 mm, and the separation portion angle of the film 8 and the sheet P being 70 degrees.
Example 4
In this example, a film 8 having an adhesive force of 15 N / cm ² between the film substrate and the coating layer formed on the film surface was used as the film 8. Further, the apparatus configuration as shown in FIG. 2 was taken with the tension for winding the film 8 being 120 gf / cm, the radius of curvature of the separation member 11 being 0.5 mm, and the separation angle of the film 8 and the sheet P being 100 degrees.
(Comparative Example 1)
In this comparative example, as the film 8, the film 8 having an adhesive force of 1 N / cm ² between the film base and the coating layer formed on the film surface was used. Further, the apparatus configuration as shown in FIG. 3 was set such that the tension for winding the film 8 was 120 gf / cm, the radius of curvature of the separation member 11 was 0.5 mm, and the separation portion angle between the film 8 and the sheet P was 70 degrees.
(Comparative Example 2)
In this comparative example, as the film 8, the film 8 having an adhesive force of 10 N / cm ² between the film base and the coating layer formed on the film surface was used. Further, the apparatus configuration as shown in FIG. 3 was obtained by setting the tension for winding the film 8 to 185 gf / cm, the radius of curvature of the separation member 11 to 0.5 mm, and the separation angle of the film 8 and the sheet P to 70 degrees.
(Comparative Example 3)
In this comparative example, as the film 8, the film 8 having an adhesive force of 10 N / cm ² between the film base and the coating layer formed on the film surface was used. Further, the apparatus configuration as shown in FIG. 3 was set such that the tension for winding the film 8 was 120 gf / cm, the radius of curvature of the separation member 11 was 0.1 mm, and the separation part angle between the film 8 and the sheet P was 70 degrees.
(Comparative Example 4)
In this comparative example, as the film 8, the film 8 having an adhesive force of 15 N / cm ² between the film base and the coating layer formed on the film surface was used. Further, the apparatus configuration as shown in FIG. 3 was set such that the tension for winding the film 8 was 1 gf / cm, the radius of curvature of the separation member 11 was 0.5 mm, and the separation portion angle between the film 8 and the sheet P was 70 degrees.
(Comparative Example 5)
In this comparative example, as the film 8, the film 8 having an adhesive force of 15 N / cm ² between the film base and the coating layer formed on the film surface was used. Further, the apparatus configuration as shown in FIG. 3 was set such that the tension for winding the film 8 was 120 gf / cm, the radius of curvature of the separation member 11 was 10 mm, and the separation portion angle between the film 8 and the sheet P was 70 degrees.

In each Example, the film 8 whose adhesive force of the film base material and the coating layer formed in the film surface is 10 N / cm < ² > or more is used. On the other hand, in Comparative Example 1, since the film having an adhesive force between the film substrate and the coat layer of 10 N / cm ² or less is used, the coat layer is peeled off from the film substrate.
Moreover, in each Example, the tension | tensile_strength which winds up the film 8 shall be 2 gf / cm or more and 170 gf / cm or less, and the peeling of the coating layer from a film base material is suppressed. On the other hand, in the comparative example 2, since the tension for winding the film 8 is 170 gf / cm or more, the coating layer is peeled off. In Comparative Example 3, since the tension for winding the film 8 is 2 gf / cm or less, the film 8 and the sheet P cannot be released.
Moreover, in each Example, the curvature radius of the separation member 11 shall be 0.5 mm or more and 3.0 mm or less, and the peeling of the coating layer from a film base material is suppressed. On the other hand, in Comparative Example 3, since the radius of curvature of the separation member 11 is 0.5 mm or less, the coat layer is peeled off. In Comparative Example 4, since the curvature radius of the separating member 11 is 3.0 mm or more, the film 8 and the sheet P cannot be released.

  In Examples 2, 3, and 4, the tension for winding the film 8 is 15 gf / cm or more, the radius of curvature of the separation member 11 is 2.0 mm or less, and the force for separating the film 8 and the sheet P is applied to the separation member 11. I tried to get enough. Thereby, the gloss failure resulting from the change in the separation position between the film 8 and the sheet P could be suppressed. On the other hand, in Example 1, since the tension for winding the film 8 is 15 gf / cm or less and the radius of curvature of the separation member 11 is 2.0 mm or more, the position where the film 8 is separated from the image is more than the normal separation position. Shifting in the paper discharge direction, the image surface shape is distorted and gloss is reduced.

  In Example 4, the separation angle between the film 8 and the sheet P is 90 degrees or more (obtuse angle), that is, the sheet P is wound so as to be folded at an acute angle with respect to the conveyance direction of the film 8. With this configuration, it is possible to suppress a paper discharge failure caused by the film 8 entering the sheet feeding roller 4 without being separated from the image. On the other hand, in Examples 1, 2, and 3, the separation angle θ between the film 8 and the sheet P is 90 degrees or less (acute angle). For this reason, if gloss processing is performed on 50 images, the film 8 and the sheet feed roller 4 enter the sheet feed roller 4 without being separated from each other, and the film 8 is wound around the sheet feed roller 4 and discharged. There was a case where a defect occurred.

  5 ... Platen roller, 6 ... Thermal head, 8 ... Transfer film, 11 ... Separating member, 12 ... Film take-up shaft, N ... Nip part, P ... Recording paper

Claims (3)

A heater,
A transfer film slidable on the heater;
A pressure member provided on the side opposite to the heater with respect to the transfer film;
With
At the nip portion between the transfer film and the pressure member, the sheet on which the image is formed is moved relative to the heater together with the transfer film and is carried on the image forming surface side of the sheet. A gloss processing device that applies gloss processing by transferring the surface shape of the transfer film by heating and pressing a thermoplastic resin material,
Winding means for winding the transfer film;
A separation member that contacts the surface of the transfer film opposite to the contact surface with the sheet and separates the transfer film wound up by the winding means from the sheet onto which the surface shape of the transfer film is transferred; ,
With
The heater has a plurality of heating elements arranged on a substrate, and is configured to be able to control a heating area to the sheet,
In the gloss processing apparatus in which the adhesive force between the film base of the transfer film and the coat layer formed on the film base and in contact with the sheet is 10 N / cm ² or more,
While forming the contact surface of the separation member with the transfer film as a substantially arc surface with a radius of curvature of 0.5 mm to 3.0 mm,
A gloss processing apparatus, wherein a tension for winding the transfer film by the winding means is 2 gf / cm or more and 170 gf / cm or less. The contact surface of the separation member with the transfer film is formed with a substantially arc surface with a radius of curvature of 0.5 mm to 2.0 mm,
The gloss processing apparatus according to claim 1, wherein a tension for winding the transfer film by the winding unit is 15 gf / cm or more and 170 gf / cm or less.   The separation angle formed by a direction in which the transfer film is pulled by the winding unit and a direction in which the sheet is conveyed after the transfer film and the sheet are separated is greater than 90 degrees. Or the glossiness processing apparatus of 2.

Images