JPH081972A - Image recording apparatus - Google Patents

Abstract

PURPOSE:To independently operate an image forming process forming an image on the image receiving layer of an intermediate transfer recording medium from a thermal transfer sheet and an image transfer process transferring the image to a receiving material from the intermediate transfer recording medium in a thermal transfer type image recording apparatus performing both processes in-line. CONSTITUTION:A buffer part C capable of regulating the length of an intermediate transfer recording medium is provided between an image forming part A transferring a colorant from the colorant layer of a thermal transfer sheet 1 to the image receiving layer of the intermediate transfer recording medium 2 to form an image and an image transfer part B transferring the image formed on the image receiving layer of the intermediate transfer recording medium to a receiving material 3 along with the image receiving layer. Even when the feed speed of the intermediate transfer recording medium is different between the image forming part A and the image transfer part B, an image forming process and an image transfer process can be parallelly performed at the same time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to image recording by a heat-sensitive transfer system, and more particularly, an image recording apparatus for forming an image on an object to be transferred which cannot directly form an image on the surface thereof by the heat-sensitive transfer system. It is about.

[0002]

2. Description of the Related Art Conventionally, a thermal transfer sheet having a color material layer provided on one surface of a base sheet, and a transfer target provided with an image receiving layer as needed are used as a heating device such as a thermal head. It is pressed against the platen roller to selectively generate heat in the heating portion of the heating device according to the image information, and the color material contained in the color material layer on the thermal transfer sheet is transferred to the transfer target to record an image. Various thermal transfer systems have been proposed.
Among them, the heat-sensitive melting transfer method and the heat-sensitive sublimation transfer method are widely used.

The heat-sensitive melt transfer system uses a heat transfer sheet in which a base material sheet such as a plastic film carries a heat-melting ink layer in which a coloring material such as a pigment is dispersed in a binder such as a heat-melting wax or a resin. An image forming method in which a coloring material is transferred together with a binder onto an object to be transferred such as paper or a plastic sheet by applying energy corresponding to image information of a heating device such as a thermal head. An image formed by this heat-sensitive melt transfer method has high density and excellent sharpness, and is suitable for recording binary images such as characters and line drawings. Further, it is possible to form a multicolor or color image by superposing and recording on a transfer target using a thermal transfer sheet of yellow, magenta, cyan, black or the like.

The thermal sublimation transfer system is a thermal transfer sheet in which a dye layer obtained by melting or dispersing a sublimable dye used as a color material in a binder resin is carried on a base material sheet such as a plastic film, and a support such as paper or a plastic sheet. By using an object to be transferred having an image receiving layer on the body, by applying energy according to the image information of a heating device such as a thermal head, the sublimable dye contained in the dye layer on the thermal transfer sheet is removed. It is a method of recording an image by transferring it to an image receiving layer on a transfer target. In this thermal sublimation transfer method, the transfer amount of the dye can be controlled in dot units depending on the amount of energy applied to the thermal transfer sheet, and thus gradation reproduction by density modulation is possible. In addition, since the coloring material used is a dye, the image formed is transparent and has excellent reproducibility of intermediate colors when colors are overlapped by using a plurality of dye layers. Therefore, a high-quality full-color image can be obtained by recording three or four colors of yellow, magenta, and cyan, or a four-color thermal transfer sheet in which black is added to the transferred material in an overlapping manner. Can be formed.

Among these image forming systems by thermal transfer, particularly in the latter thermal sublimation transfer system, it is necessary that the image receiving surface of the transferred material has dyeing property.
It was almost impossible to form an image on a transfer body without an image receiving layer. For this reason, as a method of forming an image on a transfer target other than the dedicated paper in which the image receiving layer is preset by the thermal sublimation transfer method, the image receiving layer is formed on the base sheet so that the image can be peeled off from the transfer sheet. A technique has been proposed in which an image is formed by transferring a receptor layer onto a transfer medium and then transferring a color material from a thermal transfer sheet (see JP-A-62-264994). However, in this method, the image receiving layer on the transferred material is strongly affected by the surface quality of the transferred material, and transfer marks of the image receiving layer are generated in the recesses of the transferred material, or the surface of the transferred material is uneven. As a result, the surface of the image receiving layer becomes uneven, which may cause unevenness in the recorded image. Therefore, in order to obtain a good image-formed product, it is necessary to select a transfer target having a smooth surface.

Therefore, in order to enable formation of an image on an arbitrary transferred material and to prevent the image quality from being affected by the surface irregularities and texture of the transferred material, first, the image receiving layer is used as a base sheet. An image is formed by transferring a sublimation dye from a thermal transfer sheet having a dye layer formed on a base material sheet onto an image receiving layer of an intermediate transfer recording medium which is peelably provided on the intermediate transfer recording medium. A method has been proposed in which the image receiving layer on which an image is formed is transferred onto a transfer target by heating (see JP-A-62-238791). There is also known one in which the image forming step for the image receiving layer of the intermediate transfer recording medium and the image transferring step for transferring the image from the intermediate transfer recording medium to the transfer target are performed in-line (Japanese Patent Laid-Open No. 61-106273). Issue).

[0007]

However, in the above-described in-line type image recording apparatus, the first transfer portion (image forming portion) for performing the image forming step and the second transfer portion (image for performing the image transferring step). Since the intermediate transfer recording medium is simultaneously conveyed in the transfer section), there are the following problems. Since the path of the intermediate transfer recording medium is long, it is difficult to control the tension, and feeding defects such as uneven feeding and wrinkles are likely to occur. In particular, a thin film base material is used for the intermediate transfer recording medium, but if the tension is too high, the film base material may be stretched or cause misregistration. Also,
If the tension is too low, it may cause skew and wrinkles. If the thermal head is moved up / down or the heat roller is pressed / separated in one unit during the printing operation, the tension changes because the path of the intermediate transfer recording medium changes, and the other units are easily affected. It may cause uneven feeding or misalignment. In order to perform image formation on the intermediate transfer recording medium and image transfer to the transfer target material in parallel at the same time, the feeding speed of the intermediate transfer recording medium in both units must be the same. When it is necessary to change the feeding speed of the intermediate transfer recording medium in both units, the image formation and the image transfer to the transfer target cannot be performed in parallel at the same time, so the efficiency is reduced.

The present invention has been made in view of the above problems, and an object thereof is to operate the image forming section and the image transfer section independently of each other even though they are in-line. An object is to provide an image recording apparatus capable of performing

[0009]

In order to achieve the above object, an image recording apparatus according to the present invention comprises at least a first conveying means for conveying an intermediate transfer recording medium, a thermal transfer sheet conveying means, Heating means for selectively forming heat according to image information and transferring the color material from the color material layer provided on the thermal transfer sheet to the image receiving layer provided on the intermediate transfer recording medium to form an image; An image forming section comprising an intermediate transfer recording medium and a platen roller for pressing the thermal transfer sheet against the heating means; at least a second conveying means for the intermediate transfer recording medium; And an image transfer section comprising a heating unit and a pressure unit for transferring the image formed on the image receiving layer of the intermediate transfer recording medium to the transfer target together with the image receiving layer. Inline type In the image recording apparatus, during the image forming unit and an image transfer unit and is characterized in that a buffer portion which is adjustably configure the length of the intermediate transfer recording medium.

Here, at least the image forming unit is
The first transfer unit of the intermediate transfer recording medium, the transfer unit of the thermal transfer sheet, and the heat transfer sheet selectively generate heat in accordance with image information, and are provided on the intermediate transfer recording medium from the color material layer provided on the thermal transfer sheet. A heating means for transferring a color material to the image receiving layer to form an image, and a platen roller for pressing the intermediate transfer recording medium and the thermal transfer sheet to the heating means, and the image transfer portion is at least, A second conveying means for the intermediate transfer recording medium, a conveying means for the transferred material, a heating means for transferring the image formed on the image receiving layer of the intermediate transfer recording medium to the transferred material together with the image receiving layer, and And a pressurizing means.

In the image recording apparatus having the above structure, it is preferable to provide a tension applying means for the intermediate transfer recording medium between the image forming section and the buffer section. Further, the unwinding roller of the intermediate transfer recording medium is provided with a tension applying means for the intermediate transfer recording medium, or further, the tension applying means for the intermediate transfer recording medium is provided between the unwinding roller of the intermediate transfer recording medium and the platen roller. It is preferable to provide it.

Further, it is preferable to provide a tension applying means for the intermediate transfer recording medium between the buffer section and the image transfer section.

Further, it is preferable that the unwinding roller for the thermal transfer sheet is provided with a tension applying means for the thermal transfer sheet, and the winding roller for the thermal transfer sheet is provided with a tension applying means for the thermal transfer sheet.

[0014]

In the image recording apparatus of the present invention having the above structure, the length of the intermediate transfer recording medium is adjusted in the buffer section,
This makes it possible to independently control the image forming process in the image forming unit and the image transferring process in the image transferring unit.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically shows the main part of an image recording apparatus as an embodiment of the present invention.

In FIG. 1, A indicates an image forming portion. In this image forming portion A, a thermal head 10 as a heating means is arranged so as to face the platen roller 11, and thermal transfer is performed so as to pass between them. The sheet 1 and the intermediate transfer recording medium 2 are conveyed. The platen roller 11 is driven by a stepping motor 12 to rotate at a predetermined speed, and the intermediate transfer recording medium 2 and the thermal transfer sheet 1 are positioned with the thermal head 10 separated from the platen roller 11. .

The intermediate transfer recording medium 2 is conveyed leftward or rightward and positioned as described later. The thermal transfer sheet 1 is unwound from the unwinding roller 13 and the take-up roller 1
By being wound around 4, the sheet is conveyed rightward, and first, the first color (yellow) is positioned. When the positioning of the intermediate transfer recording medium 2 and the thermal transfer sheet 1 is completed, the thermal head 1 is moved by a thermal head elevating means (not shown).
0 moves toward the platen roller 11, and the intermediate transfer recording medium 2 is pressed against the platen roller 11 by the thermal head 10 while being superposed on the thermal transfer sheet 1.
Next, the intermediate transfer recording medium 2 is conveyed rightward together with the thermal transfer sheet 1 by the rotation of the platen roller 11,
In synchronization with this, the thermal head 10 selectively generates heat according to the image data transferred from the thermal head drive circuit to the thermal head 10, and the first color (yellow) is printed.

When the printing of the first color is completed, the thermal head 10 is separated from the platen roller 11 by the thermal head elevating means, and the intermediate transfer recording medium 2 and the thermal transfer sheet 1 are positioned before printing the second color. That is, the intermediate transfer recording medium 2 is rewound so that the front end portion of the image forming area for the first color overlaps the heating element line of the thermal head 10, and the thermal transfer sheet 1 is conveyed rightward by the take-up roller 14 to be secondly transferred. Positioning of the color (magenta) is performed. After that, in the same way as the first color print, 2
Printing of the color (magenta) and the third color (cyan) is performed. Further, black may be printed in addition to the above three colors if necessary.

In FIG. 1, B indicates an image transfer section. In this image transfer section B, a thermal head 20 which is a heating means is arranged so as to face a platen roller 21 which is a pressurizing means, and a space between these is provided. The intermediate transfer recording medium 2 and the transferred material 3 are conveyed so as to pass therethrough. Platen roller 2
1 is driven by a stepping motor 22 to rotate at a predetermined speed, and the intermediate transfer recording medium 2 and the transferred body 3 are positioned with the thermal head 20 separated from the platen roller 21.

When transferring an image, the intermediate transfer recording medium 2 is conveyed rightward as described below so that the leading end of the area where the image to be transferred is formed overlaps the nip position between the thermal head 20 and the platen roller 21, and the intermediate position. Positioning of the transfer recording medium 2 is performed. On the other hand, the transferred body 3 is fed by a paper feeding means (not shown), and the position on the transferred body 3 where the image is to be transferred is at the thermal head 20 and the platen roller 2.
It is positioned so as to overlap the nip position of 1. The thermal head 20 is brought into pressure contact with the platen roller 21 via the intermediate transfer recording medium 2 and the transferred body 3 by an elevating means (not shown), and the platen roller 21 rotates to move the intermediate transfer recording medium 2 to the transferred body 3 rightward. Then, the image transfer is started. When the intermediate transfer recording medium 2 is conveyed to the rear end of the area where the image is to be transferred, and when the image transfer is completed, the thermal head is separated from the platen roller 21 by the elevating means, and the transferred body 3 to which the image is transferred is shown in the figure. The sheet is discharged by the sheet discharging means.

In FIG. 1, C is a buffer section provided between the image forming section A and the image transfer section B, which is a pair of fixed pulleys 30 arranged at intervals in the middle of the conveying path of the intermediate transfer recording medium 2. , 31 and a pair of movable pulleys 32 and 33 below which are movable to the left and right, respectively, and one fixed pulley 34 located below the movable pulleys 32 and 33. It is hung around a pulley and transported in a detoured state. Therefore, in the image recording apparatus provided with the buffer section C, the intermediate transfer recording medium 2 is transported from the image forming section A to the image transfer section B while bypassing the inside of the buffer section C, so that the image forming step and the image transfer step are performed. Is done inline. It should be noted that this buffer unit may be configured so that the length of the path between the image forming unit and the image transfer unit can be adjusted independently so that the conveyance of the intermediate transfer recording medium can be independently controlled. Is not particularly limited.

The thermal transfer sheet 1 is conveyed by being unrolled from the unwinding roller 13 and wound up by the winding roller 14 as described above. The winding roller 14 is connected to a pulley of a motor 15 via a belt 16,
By controlling the motor 15 by the motor drive circuit,
The take-up roller 14 rotates counterclockwise. Here, in order to stably convey the thermal transfer sheet 1 without causing wrinkles or uneven feeding, it is preferable to apply an appropriate tension to the thermal transfer sheet 1.

Rolling roller 13 from thermal head 10
To apply tension to the thermal transfer sheet 1 on the side,
As shown in FIG. 3, the rotation shaft 1a of the unwinding roller 13 is provided between the rotation shaft 13a of the unwinding roller 13 and the bearing portion 40.
It suffices to provide a friction clutch 41 including two friction plates 41a and 41b connected to the rotating shaft 40a of the bearing portion 40 and 3a. The two friction plates 41a and 41b are pressed against each other by urging means 42 and 43 such as springs.
When the unwinding roller 1 is unwound from the unwinding roller 13, the friction plate 41a on the rotary shaft 13a side of the unwinding roller 13 is
The friction plate 41b on the side of the bearing 40 does not rotate. Therefore, in order to unwind the thermal transfer sheet 1 from the unwinding roller 13, the thermal transfer sheet 1 is thermally transferred so that the rotational torque that overcomes the frictional force between the two friction plates 41a and 41b is applied to the rotary shaft 13a of the unwinding roller 13. By pulling toward the head 10, the thermal transfer sheet 1 is given a predetermined tension. Further, the tension can be controlled by adjusting the frictional force between the two friction plates 41a and 41b.

To apply tension to the thermal transfer sheet 1 between the thermal head 10 and the take-up roller 14, the take-up roller 14 has a rotating shaft 14a as shown in FIG.
A friction clutch 46 including two friction plates 46a and 46b may be provided between the rotary shaft 45a of the bearing portion 45 on the motor 15 side. The two friction plates 46a and 46b are pressed against each other by biasing means 47 and 48 such as springs. When the thermal transfer sheet 1 is wound onto the winding roller 14, the rotational torque of the motor 15 is wound via the friction clutch 45. Taking roller 14
Is configured to be transmitted to the rotary shaft 14a. Therefore, by setting the rotation speed of the rotation shaft 45a of the bearing portion 45 on the motor 15 side to be higher than the rotation speed of the take-up roller 14 corresponding to the conveyance speed of the thermal transfer sheet 1,
Friction occurs between the friction plates 46a and 46b, and tension is applied to the thermal transfer sheet 1. Further, the tension can be controlled by adjusting the frictional force between the two friction plates 46a and 46b and the rotation speed of the motor 15.

Intermediate transfer recording medium 2 in image forming section A
The conveyance to the right is performed by the platen roller 11 and the movable pulley 32 provided in the buffer C. The movable pulley 32 is biased to the left by a biasing means such as a spring, and the biasing force pulls the intermediate transfer recording medium 2 to the right. During the printing operation, the intermediate transfer recording medium 2 is unwound from the unwinding roller 17 and conveyed rightward by the rotation of the platen roller 11, and the intermediate transfer recording medium 2 that has passed through the thermal head 10 moves in the buffer section C. When the pulley 32 moves leftward, it is pulled and conveyed rightward. On the other hand, the feeding of the intermediate transfer recording medium 2 to the left is performed by the unwinding roller 17.
That is, the unwinding roller 17 is connected to the pulley of the motor 18 via the belt 19, and the motor 18 is controlled by the motor drive circuit to rotate the unwinding roller 17 in the counterclockwise direction and thereby the intermediate transfer recording medium. Rewind 2 to the left.

In order to control the tension applied to the intermediate transfer recording medium 2 between the image forming section A and the buffer section C more accurately and convey the intermediate transfer recording medium 2 more stably, as shown in FIG. A roller pair including a capstan roller 51 driven by a motor 50 so as to rotate at a constant speed and a nip roller 52 that presses the intermediate transfer recording medium 2 against the capstan roller 51 is provided between the thermal head 10 and the buffer portion C. It may be provided. In this case, the capstan roller 51 serves as a drive unit that conveys the intermediate transfer recording medium 2 to the right. That is, in the configuration of FIG. 1, since the movable pulley 32 of the buffer C is biased by the spring or the like, when the length of the intermediate transfer recording medium 2 in the buffer C changes, the position of the movable pulley 32 changes. As a result, the urging force applied to the movable pulley 32 changes. Therefore, the tension applied to the intermediate transfer recording medium 2 between the thermal head 10 and the buffer C varies depending on the length of the intermediate transfer recording medium 2 in the buffer C. On the other hand, when the roller pair is provided between the thermal head 10 and the buffer portion C as shown in FIG. 4, the linear velocity of the surface of the capstan roller 51 in contact with the intermediate transfer recording medium 2 is changed to the platen. By making the roller 11 slightly larger than that of the roller 11, the tension applied to the intermediate transfer recording medium 2 between the thermal head 10 and the roller pair can always be controlled to be constant even if the position of the movable pulley 32 changes. . In this way, the thermal head 10
By providing the roller pair between the buffer portion C and the buffer portion C, it is possible to prevent the occurrence of uneven feeding and wrinkles of the intermediate transfer recording medium 2 due to the fluctuation of tension.

In order to stabilize the traveling of the intermediate transfer recording medium 2, it is preferable to apply an appropriate tension to the intermediate transfer recording medium 2 between the unwinding roller 17 and the platen roller 11. As a means for applying this tension, as shown in FIG. 5, a rotating shaft 17a of the unwinding roller 17 is used.
It can be realized by combining a one-way clutch 56 and a friction clutch 57 between the bearing portion 55 on the side of the motor 18 and the bearing portion 55 on the side of the motor 18. That is, in FIG. 1, the unwinding roller 17
When the rotary shaft 17a of the unwinding roller 17 rotates in the clockwise direction, the space between the unwinding roller 17 side and the bearing portion 55 side is rotatable, and when the rotating shaft 17a of the unwinding roller 17 rotates in the counterclockwise direction, Rotating shafts 17a and 5 on the roller 17 side and the bearing 55 side
The one-way clutch 56 may be provided so that 5a rotates integrally. With this configuration, when the intermediate transfer recording medium 2 is fed from the unwinding roller 17, a tension corresponding to the frictional force acting between the two friction plates 57a and 57b of the friction clutch 57 is applied. It is given to 2.

Alternatively, as shown in FIG. 6, a capstan roller 61, which is driven by a motor 60 so as to rotate at a constant speed, is provided between the unwind roller 17 and the platen roller 11.
Also, a roller pair including a nip roller 62 that presses the intermediate transfer recording medium 2 against the capstan roller 61 may be provided. In this case, the intermediate transfer recording medium 2 can be fed from the unwinding roller 17 by rotating the capstan roller 61 at a predetermined speed. Further, when only the one-way clutch 56 and the friction clutch 57 are used, since the driving force is transmitted by the friction between the two friction plates 57a and 57b, the rotation amount of the motor 18 and the intermediary transfer recording medium 2 are changed. Although the movement amount does not correspond, when the roller pair is provided, since the rotation amount of the motor 60 and the movement amount of the intermediate transfer recording medium 2 are in a proportional relationship, by controlling the rotation amount of the motor 60, Positioning of the intermediate transfer recording medium 2 can be accurately performed. Further, when the intermediate transfer recording medium 2 is fed to the right, the linear velocity of the surface of the capstan roller 61 in contact with the intermediate transfer recording medium 2 is made slightly smaller than that of the platen roller 11, so that the unwinding roller 17 moves. The intermediate transfer recording medium 2 between the thermal head 10 and the roller pair irrespective of the fluctuation of the outer diameter.
It is possible to always control the tension applied to the. The roller pair is the one-way clutch 56 described above.
It may also be used in combination with the friction clutch 57.

In the above description, the platen roller 1
1, separate motors are provided to drive the take-up roller 13 of the thermal transfer sheet and the capstan rollers 51 and 61 of the roller pair, but they may be shared.

Intermediate transfer recording medium 2 in image transfer section B
Is carried by the take-up roller 23. That is, the take-up roller 23 is connected to the pulley of the motor 24 through the belt 25, and the take-up roller 23 is controlled by the motor drive circuit.
Rotate clockwise. When the thermal head 20 is separated from the platen roller 21, the intermediate transfer recording medium 2 is conveyed from the buffer section C to the take-up roller 23 side by the rotation of the take-up roller 23. Further, in a state where the thermal head 20 is in pressure contact with the platen roller 21, the intermediate transfer recording medium 2 is conveyed rightward from the buffer portion C by the rotation of the platen roller 21, and passes through the platen roller 21. Is taken up by the take-up roller 23.

In the above example, the movable pulley 33 of the buffer C is used.
Is urged to the right by an urging unit (not shown), and the intermediate transfer recording medium 2 in the image transfer section B is pulled by the buffer section C (back tension). A force greater than this is applied to the take-up roller 23 side, and the intermediate transfer recording medium 2
Thus, the intermediate transfer recording medium 2 can be conveyed from the buffer section C to the take-up roller 23 side. However, since the biasing means of the movable pulley 33 is composed of a coil spring or the like, the back tension varies depending on the position of the movable pulley 33, which causes uneven feeding or wrinkles of the intermediate transfer recording medium 2 which causes defective image transfer. Likely to happen. Therefore, in order to stabilize the traveling of the intermediate transfer recording medium 2, as shown in FIG. 7, the buffer portion C and the platen roller 21 are
It is preferable to provide a roller pair including a capstan roller 66 driven by a motor 65 so as to rotate at a constant speed and a nip roller 67 that presses the intermediate transfer recording medium 2 against the capstan roller 66. That is, the intermediate transfer recording medium 2 can be conveyed from the buffer section C to the image transfer section B by rotating the capstan roller 66 at a predetermined speed. In addition, the capstan roller 6
By making the linear velocity of the surface of No. 6 which is in contact with the intermediate transfer recording medium 2 slightly smaller than that of the platen roller 21, it becomes possible to always control the linear velocity regardless of the position of the movable pulley 33. In the present embodiment, the platen roller 21, the winding roller 23 for the intermediate transfer recording medium 2,
In order to drive the capstan roller 66 of the roller pair,
Although separate motors are provided, they may be shared.

A thermal head is mainly used as a heating means in the image forming section A. Further, as the heating means in the image transfer portion B, a thermal head, a heat roll, hot stamping or the like can be used,
There is no particular limitation.

FIG. 8 shows a conceptual diagram of the intermediate transfer recording medium 2. The intermediate transfer recording medium 2 used in the present invention is basically a base sheet 2a having an image receiving layer 2b releasably formed on one surface thereof. In order to improve slidability between the intermediate transfer recording medium 2 and a heating means such as a thermal head, the back surface layer 2 is provided on the other surface of the base sheet 2a on the image receiving layer 2b side.
You may set c. Further, a release layer 2d may be provided between the base sheet 2a and the image receiving layer 2b in order to control the peeling of the image receiving layer 2b from the base sheet 2a. Further, an image protective layer 2e may be provided between the base material sheet 2a and the image receiving layer 2b for the purpose of protecting the image receiving layer 2b transferred together with the image formed on the transfer body. The image protection layer 2e is transferred onto the transfer target together with the image receiving layer 2b, and improves the weather resistance of the image and the durability against fingerprints and chemicals.

As the base material sheet 2a, the same base material sheet as that used in the conventional thermal transfer sheet can be used as it is, and there is no particular limitation. Specific examples of the preferable base sheet 2a include glassine paper, condenser paper,
Thin paper such as paraffin paper, polyethylene terephthalate,
Polyethylene naphthalate, polybutylene terephthalate, polyphenylene sulfide, polyether ketone, high heat-resistant polyester such as polyether sulfone, polypropylene, polycarbonate, cellulose acetate, polyethylene derivatives, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, Polyimide,
Examples include stretched or unstretched films of plastics such as polymethylpentene and ionomers, and laminates of these materials. The thickness of the base material sheet 2a can be appropriately selected depending on the material so that the strength and heat resistance are appropriate, but normally a thickness of about 1 to 100 μm is preferably used.

The image receiving layer 2b is made of at least a binder resin, and various additives such as a release agent may be added if necessary. It is preferable to use a binder resin that is easily dyed with a sublimation dye, such as polyolefin resin such as polypropylene, halogenated resin such as polyvinyl chloride or polyvinylidene chloride, vinyl resin such as polyvinyl acetate polyacrylate, polyethylene. Terephthalate,
Polyester resin such as polybutylene terephthalate,
Polystyrene resins, polyamide resins, copolymers of olefins such as ethylene and propylene with other vinyl monomers, ionomers, cellulose derivatives and the like can be used, and among these, vinyl resins and polyester resins are particularly preferable. Used.

When the image receiving layer 2b is transferred to the transferred material via the adhesive layer, it is not always necessary to impart heat-sensitive adhesiveness to the image receiving layer 2b itself. Therefore, a resin that is not easily softened by heat can be used as the resin forming the image receiving layer 2b.

The image receiving layer 2b is preferably blended with a releasing agent in the above resin in order to prevent heat fusion with the thermal transfer sheet. As the release agent, silicone oil, phosphoric acid ester-based surfactant, fluorine-based compound and the like can be used, and among these, silicone oil is particularly preferably used. The amount of the release agent added depends on the amount of the image receiving layer 2
0.2 to 100 parts by weight of the binder resin forming b
30 parts by weight is preferred. The image-receiving layer 2b is prepared by adding a necessary additive such as a release agent to the above resin on the base sheet 2a, and dissolving or dispersing the ink in a solvent such as water or an organic solvent by a gravure printing method. The coating can be performed by a usual method such as a screen printing method or a reverse roll coating method using a gravure plate. The coating amount is preferably such that the film thickness after coating and drying is 0.1 to 10 μm.

The release layer 2d contains a binder resin and a release material. Examples of the binder resin include acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, and polybutyl acrylate, which are thermoplastic resins, vinyl acetate, vinyl chloride vinyl acetate copolymers, polyvinyl alcohol, polyvinyl butyral, and other vinyl resins. Resins, cellulose derivatives such as ethyl cellulose, nitrocellulose, and cellulose acetate, or unsaturated polyester resins which are thermosetting resins, polyester resins, polyurethane resins, aminoalkyd resins and the like can be used.
As the release material, waxes, silicone waxes, silicone resins, melamine resins, fluorine resins, talc, fine silica powder, lubricants such as surfactants and metal soaps can be used. The release layer can be formed by a method similar to that of the image receiving layer and has a thickness of 0.1 to
5 μm is preferable.

The image protective layer 2e is composed of at least a binder resin, but has a proper releasability from the base material sheet 2a and protects the surface of the image receiving layer 2b after being transferred together with the image receiving layer 2b to the transferred material. A resin composition having desired physical properties is selected for the layer. Generally, cellulose derivatives such as ethyl cellulose, nitrocellulose, and cellulose acetate, acrylic resins such as polymethyl methacrylate, polyethyl methacrylate, and polybutyl acrylate, polyvinyl chloride, vinyl chloride vinyl acetate copolymer, polyvinyl. A vinyl polymer thermoplastic resin such as butyral, or a thermosetting resin such as an unsaturated polyester resin, a polyurethane resin, or an aminoalkyd resin can be used. Rubbing resistance, chemical resistance,
When stain resistance is particularly required, an ionizing radiation curable resin can be used as the image protective layer resin. Also,
A lubricant for improving the scratch resistance of the image formed product, a surfactant for preventing stains, an ultraviolet absorber for improving weather resistance, an antioxidant and the like may be added to the above resins. The image protective layer can be formed in the same manner as the image receiving layer, and the thickness is preferably 0.1 to 10 μm.

The back surface layer 2c prevents heat fusion with a heating device such as a thermal head or a line heater when transferring a color material from a thermal transfer sheet and when transferring the image receiving layer 2b to a transfer object. For the purpose of smooth running, it can be provided on the other surface of the base sheet 2a in contact with the heating device on the image receiving layer side. Examples of the resin used for the back surface layer 2c include cellulosic resins such as ethyl cellulose, hydroxycellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, and nitrocellulose, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetal. , Vinyl-based resins such as polyvinylpyrrolidone, polymethyl methacrylate, polyethyl acrylate,
Polyacrylamide, acrylic resin such as acrylonitrile-styrene copolymer, polyamide resin, polyvinyltoluene resin, coumarone indene resin, polyester resin, polyurethane resin, natural or synthetic resin such as silicone modified or fluorine modified urethane, or a mixture thereof. Is used. In order to further improve the heat resistance of the back surface layer 2c, a resin having a reactive group such as a hydroxyl group is used among the above resins, and polyisocyanate or the like is used as a crosslinking agent to form a crosslinked resin layer. Is preferred. Further, in order to provide slidability with the thermal head, a solid or liquid mold release agent or lubricant may be added to the back surface layer 2c so as to have heat resistant slip property. Examples of the release agent or lubricant include various waxes such as polyethylene wax and paraffin wax, higher aliphatic alcohols, organopolysiloxanes, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants. Activators, fluorinated surfactants, organic carboxylic acids and their derivatives, fluorinated resins,
Fine particles of an inorganic compound such as silicone resin, talc, and silica can be used. The amount of lubricant contained in the back layer 15 is 5 to 50% by weight, preferably about 10 to 30% by weight.

The thermal transfer sheet 1 used in the present invention has a heat resistant slipping layer provided on one side of a base sheet and a color material layer having heat transferability on the other side. In the thermal sublimation transfer method, a known dye thermal transfer sheet using a dye layer composed of a sublimable dye and a binder resin as a color material layer is used. Further, in the heat-sensitive melt transfer method, a known thermoplastic resin melt ink transfer sheet using a melt transfer layer composed of a color material such as a pigment or a dye and a wax or a thermoplastic resin as a color material layer is used. Then, in the dye thermal transfer sheet, the dye that sublimates / migrates due to heat becomes a color material that forms an image, and when the heat-melt ink transfer sheet is used, the ink itself that melts / migrates becomes a color material.

The image finally obtained by the present invention is
Since it has a mirror image relationship with the image formed on the image receiving layer 2b of the intermediate transfer recording medium 2, it is necessary to previously form characters and symbols as a reverse image.

The material 3 to be transferred that can be used in the present invention is not particularly limited, and examples thereof include natural fiber paper, coated paper, tracing paper, plastic film that is not deformed by heat during transfer, glass, metal, ceramics, wood, cloth. Any of the above may be used. Regarding the shape and usage of the transferred material 3, stock certificates, securities, certificates, passbooks, boarding tickets, wagon tickets, stamps, stamps, appreciation tickets, admission tickets, cash vouchers such as tickets, credit cards, prepaid cards ,
Cards such as members cards, greeting cards, postcards, business cards, driver's licenses, IC cards, optical cards, cases such as cartons and containers, bags, forms,
Envelopes, tags, OHP sheets, slide films, bookmarks, calendars, posters, brochures, menus,
Passports, POP supplies, coasters, displays,
Nameplates, keyboards, cosmetics, wristwatches, accessories such as lighters, stationery, report paper, stationery, building materials, panels, emblems, keys, cloth, clothing, footwear, radios, televisions, calculators, OA equipment, and other devices. Sample book,
Album, also computer graphics output,
It does not matter what kind of medical image is output.

FIG. 9 is a conceptual diagram showing a cross-sectional state in which the image receiving layer 2b on which the image of the intermediate transfer recording medium 2 is formed and the transferred material 3 are superposed. In the figure, 2b 'indicates an image formed on the receiving layer 2b by the color material. Note that, as shown in FIG. 10, the image receiving layer 2b on which the image 2b ′ of the intermediate transfer recording medium 2 is formed may be transferred to the transfer target 3 via the adhesive layer 4.

[0045]

Since the present invention is constructed as described above, it has the following effects.

Even when the feeding speed of the intermediate transfer recording medium is different between the image forming section and the image transferring section, the image forming step and the image transferring step can be simultaneously performed in parallel, so that the printing speed is improved.

Since the tension of the intermediate transfer recording medium can be controlled more stably in the image forming section and the image transfer section, troubles such as wrinkles and uneven feeding can be prevented and high quality images can be formed. It will be possible.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a main part of an image recording apparatus that is an embodiment of the present invention.

FIG. 2 is a schematic view showing a tension applying means for a thermal transfer sheet, which is provided on a winding roller of the thermal transfer sheet.

FIG. 3 is a schematic view showing a tension applying means for a thermal transfer sheet, which is provided on a take-up roller of the thermal transfer sheet.

FIG. 4 is a schematic configuration diagram showing a tension applying unit for an intermediate transfer recording medium provided between an image forming unit and a buffer unit.

FIG. 5 is a schematic view showing a tension applying means for an intermediate transfer recording medium, which is provided on a winding roller of the intermediate transfer recording medium.

FIG. 6 is a schematic configuration diagram showing a tension imparting means for an intermediate transfer recording medium, which is provided between a winding roller and a platen roller of the intermediate transfer recording medium.

FIG. 7 is a schematic configuration diagram showing a tension applying means for providing an intermediate transfer recording medium provided between a buffer section and an image transfer section.

FIG. 8 is a conceptual diagram showing a cross section of an intermediate transfer recording medium used in the present invention.

FIG. 9 is a conceptual diagram showing a cross-sectional state in which an image receiving layer on which an image of an intermediate transfer recording medium is formed and a transferred material are superposed.

FIG. 10 is a conceptual diagram showing a cross-sectional state in which an image receiving layer on which an image of an intermediate transfer recording medium is formed and a transfer target body are superposed with an adhesive layer in between.

[Explanation of symbols]

 A image forming part B image transfer part C buffer part 1 thermal transfer sheet 2 intermediate transfer recording medium 3 transfer target 10 thermal head (heating means) 11 platen roller 20 thermal head (heating means) 21 platen roller (pressurizing means)

Claims (7)

[Claims] 1. At least a first conveying means for conveying an intermediate transfer recording medium, a conveying means for a thermal transfer sheet, and a coloring material layer provided on the thermal transfer sheet for selectively generating heat according to image information. The intermediate transfer recording medium is provided with a heating means for transferring a color material to the image receiving layer to form an image, and a platen roller for pressing the intermediate transfer recording medium and the thermal transfer sheet to the heating means. And an image forming section formed on the image receiving layer of the intermediate transfer recording medium, and at least the second conveying unit of the intermediate transfer recording medium, the conveying unit of the transfer target, and the image receiving unit of the intermediate transfer recording medium. In an in-line type image recording apparatus integrally provided with an image transfer unit including a heating unit and a pressure unit for transferring to the body, an intermediate transfer is performed between the image forming unit and the image transfer unit. Recording medium An image recording apparatus comprising a buffer section whose length is adjustable. 2. The image recording apparatus according to claim 1, further comprising a tension applying means for applying tension to the intermediate transfer recording medium between the image forming section and the buffer section. 3. The image recording apparatus according to claim 1, wherein the unwinding roller of the intermediate transfer recording medium is provided with a tension applying means for applying tension to the intermediate transfer recording medium. 4. The image recording apparatus according to claim 1, further comprising a tension applying unit for applying tension to the intermediate transfer recording medium between the winding roller and the platen roller of the intermediate transfer recording medium. 5. The image recording apparatus according to claim 1, 2, 3 or 4, wherein a tension applying means for applying tension to the intermediate transfer recording medium is provided between the buffer section and the image transfer section. 6. The image recording apparatus according to claim 1, 2, 3, 4 or 5, wherein the unwinding roller for the thermal transfer sheet is provided with a tension applying means for applying the tension to the thermal transfer sheet. 7. The image recording apparatus according to claim 1, wherein the winding roller for the thermal transfer sheet is provided with a tension applying means for applying the tension to the thermal transfer sheet.