JPH06122216A - Method and apparatus for forming image - Google Patents

Abstract

PURPOSE:To prevent the increase in thickness of recording paper beyond the required value by providing a control means for adjusting the fusing amount of a thermal recording means, which diffuses an acceptance layer in response to the roughness, the base color and the like of the surface of the paper used, and variably adjusting the thickness of the acceptance layer appropriately in response to the supplied recording paper. CONSTITUTION:An image forming apparatus forms an acceptance layer with a pretreating material on the surface of recording paper from a paper feeding mechanism by thermal transfer. Characters, graphics and the like are printed on the acceptance layer by the thermal transfer. A thermal transfer ribbon is formed by applying the pretreating material along the transfer direction, and then forming four frames of dyes, which are applied in the sequence of, e.g. yellow, Magenta and cyan as one set. Many sets of the ribbons are continuously provided. An adjusting switch W, which is the control means for adjusting the fusing amount, in a thermal recording means 20, fuses the acceptance material in response to the roughness, the base color and the like of the surface of the recording paper used. A potential U of a power supply terminal V0 is adjusted only in printing. The appropriate thickness of the layer suitable for the recording paper is adjusted by forming several samples beforehand, or adjusted by trial printing at every printing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method and apparatus for printing an image on a recording paper such as a business card sheet, a card and a postcard.

[0002]

2. Description of the Related Art Conventionally, in order to favorably form a color layer on a recording paper, as a pretreatment before image printing (color layer formation), for example, a binder material is coated on the surface of the recording paper with a binder material to improve the adhesion of dyes. Is known to do.

[0003]

However, the receiving layer is formed with a constant layer thickness regardless of the roughness of the surface of the recording paper used, the background color of the paper, and the like, and has the following problems. It was The layer thickness of the receiving layer is used so that the dye has good adhesion to any recording paper regardless of the roughness of the recording paper used and the background color of the paper. The thickness of the recording paper is excessively thicker than necessary due to the roughness of the surface of the recording paper and the background color of the surface of the paper.As a result, the recording paper becomes thick and partially receptive. When forming, there is a step between the edge of the receiving layer and the recording paper,
It is more easily peeled off than the stepped portion and scratched. In order to form the receptive layer thickly, a large amount of energy for melting the receptive layer is required, and a large amount of electric power is applied to the thermal recording means, which inevitably requires a large power supply. Therefore, the image forming apparatus cannot be made compact.

An object of the present invention is to make the layer thickness of a receiving layer formed on a recording paper suitable for the recording paper to be used in accordance with the roughness of the surface of the recording paper and the background color of the paper. An image forming method and an apparatus for forming the image are provided.

[0005]

In order to achieve the above object, the present invention provides a receiving means for receiving an image forming dye which is melted by a thermal recording means in at least an image forming area of a supplied recording paper before image forming. In the image forming method of forming an image by selectively heating the image forming dye by a thermal recording means after forming a layer, the image forming dye is transferred into the image forming area to form an image, depending on the recording paper used. The melting amount of the heat recording means for melting the receptive layer is adjusted in advance, the receptive layer is appropriately melted by the heat recording means according to the supplied recording paper, and the melted receptive layer is transferred to the recording paper. The image forming method is characterized in that the layer thickness of the receiving layer is variably adjusted. Further, before image formation, after forming a receptive layer which is melted by the thermal recording means and receives the image forming dye in at least the image forming area of the supplied recording paper, the image forming dye is selectively formed by the thermal recording means. In an image forming apparatus that heats and transfers the image forming dye into the image forming area to form an image, a control unit that adjusts the melting amount of the thermal recording unit that melts the receiving layer according to the recording paper used. The image forming apparatus is characterized in that the layer thickness of the receiving layer is variably adjusted according to the recording paper supplied.
The control means can adjust the melting amount of the thermal recording means according to the roughness of the recording surface of the recording paper used, or can adjust the melting amount of the thermal recording means according to the background color of the recording paper used. The layer thickness of the receiving layer is variably adjusted according to the roughness of the recording surface of the recording paper and the background color.

[0006]

The present invention adjusts the melting amount of the thermal recording means according to the roughness of the recording surface of the recording paper to be used, the background color, etc. The layer thickness can be adjusted variably.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

<Structure> First, the structure of this apparatus will be described.

[Overall Structure] First, FIG. 1 illustrates an apparatus for continuously printing a large number of business cards as an image forming apparatus. This device is arranged with the right side of FIG. 1 facing the operator. Further, this device is operated by being connected to a personal computer (not shown) or the like. Reference numeral 1 is a casing of the device. On one side of the apparatus (the upper surface on the right side in FIG. 1 in this example), a paper feeding unit, for example, a recording paper S for printing a business card is provided.
A paper feed mechanism 2 for feeding (recording paper) one by one is arranged. In addition, the first printing unit, which is separated from one side of the apparatus,
For example, after forming a receiving layer by a pretreatment material such as a binder material as a pretreatment on the surface of the recording paper S sent from the paper feeding mechanism 2 by thermal transfer, characters and figures are printed on the receiving layer by thermal transfer. Receptive layer / image forming mechanism 3
Is provided. It should be noted that this receiving layer forming step is not necessary for the coated paper which has been surface-treated in advance, but it is necessary for the plain paper to improve the adhered state of the dye, for example. Further, the thermal transfer method includes a melting type in which the dye is attached to the recording paper S in a molten state and a sublimation type in which the dye is attached in a vaporized state. In the case of the sublimation type, the formation of the receiving layer is particularly necessary. Further, on one side of the apparatus (lower right side in FIG. 1 in this example), a protective layer such as a transparent material is formed on the surface of the image-formed recording sheet S conveyed from the receiving layer / image forming mechanism 3 by thermal transfer. A protective layer forming mechanism 4 for covering the above is provided. A sheet feeding path 5 for conveying the recording sheet S from the sheet feeding mechanism 2 to the receiving layer / image forming mechanism 3 is provided. Also, the receiving layer / image forming mechanism 3
A paper discharge path 6 that conveys the recording paper S from to the protective layer forming mechanism 4 is provided. Reference numeral 7 denotes a feed roller provided on the paper discharge path 6. Downstream of the protective layer forming mechanism 4, a paper discharge tray 8 for storing the recording paper S for which printing has been completed is arranged.

FIG. 2 is a perspective view showing the external appearance of the apparatus shown in FIG. 1, and is a discharge tray 8 which is openably and closably supported for accumulating the recording sheets S which have been subjected to the image forming process and discharged on the front side.
In addition to the display starter P, the print start switch, the print jam cancel switch, and the like, and the display panel P containing the display unit for displaying the print status, the number of prints, and the like, the surface roughness of the recording paper S to be used, An adjusting switch W is provided which is a control unit that adjusts the melting amount of the thermal recording unit 20 that melts the receiving layer according to the background color of the paper. This adjusting switch W varies the potential V applied to the thermal recording paper means 20 in FIG. 9 which will be described later, and when the roughness of the recording paper surface is small (a) as shown in FIG. Is adjusted to be as thin as t1, and conversely, when the surface roughness of the recording paper is large (b), the receiving layer is adjusted to be as thick as t2, and as shown in FIG. In the case of (a) in which the background color of the recording paper is the same color as the color of the receiving layer, the layer thickness of the receiving layer is adjusted to be thin at t3. In the case of the different color system (b), the layer thickness of the receiving layer is adjusted to be as thick as t2, and the layer is formed to have an appropriate layer thickness suitable for the recording paper. The appropriate layer thickness on the recording paper may be adjusted by making some samples in advance, or may be adjusted and set by trial printing each time printing is performed. In some cases, depending on the background color of the recording paper, the thickness of the receiving layer may be thinned contrary to the above.

[Structure of Paper Feeding Mechanism 2] Next, the paper feeding mechanism 2 will be described with reference to FIG. 1 and FIG. Reference numeral 9 is a paper feed tray for stacking and storing the recording paper S. An alignment guide 10 that moves in the width direction of the paper feed tray 9 to align the bundle of recording paper S in the lateral direction is provided on the side of the paper feed tray 9. A separation gate 11 is provided at the leading end of the paper feed tray 9 to separate and send out only one recording sheet S from the gap between the paper feed tray 9. The separation gate 11 can be moved up and down to adjust the gap between the separation gate 11 and the paper feed tray 9 according to the thickness of the recording paper S. Below the paper feed tray 9, a feeding roller 12 that feeds from the lowest recording paper S on the paper feed tray 9 is provided. Downstream of the paper feed tray 9,
A pair of feed rollers 13 is provided. The feed rollers 13 are provided such that they can be separated from each other and pressed against each other. Downstream of the feed roller 13, a pair of registration rollers 14 is provided which abuts the leading edge of the recording sheet S to correct the left-right bending (skew) of the leading edge of the recording sheet S. A switching gate 15 that switches the conveyance path is provided downstream of the registration rollers 14. This switching gate 15 is
A spring 16 is constantly urged to close the paper feed path 5 and open the paper discharge path 6. Feeding roller 1
2, the feed roller 13, the registration roller 14, etc.,
It is connected to a second drive system described later. The recording paper S sensor 17 counts the number of fed recording papers S and detects the rear end of the recording paper S in order to control and determine the printing start position.

[Structure of Receptive Layer / Image Forming Mechanism 3] Next,
The receiving layer / image forming mechanism 3 will be described with reference to FIG. 1 and FIGS. 6 and 7. A pinch roller 19 is press-contacted to a drivable grid roller 18 downstream of the switching gate 15 so as to be driven. The grid roller 18 has a large number of irregularities formed on its outer periphery so that the recording paper S can be fed without slipping. The pinch roller 19 moves on the outer circumference of the grid roller 18 following the operation of the platen described later (see FIGS. 6 and 7). Downstream of the grid roller 18 and the pinch roller 19, there is provided a head 20 that heats according to image information during thermal transfer. The thermal transfer ribbon 21 and the recording paper S are superposed between the head 20 and a platen, which will be described later, and are thermally transferred in a state of being pressed against each other. 22 is a fan for cooling the head. The feed reel 23 around which the thermal transfer ribbon 21 is wound, and the feed reel 2
A take-up reel 24 for winding the thermal transfer ribbon 21 pulled out from the No. 3 via the head 20 is provided. Then, a transport roller 25 for transporting the thermal transfer ribbon 21 is provided, and a torque limiter (not shown) is used for the transport roller 25 and the take-up reel 24, so that the thermal transfer ribbon 21 can be changed due to a change in the winding diameter of the thermal transfer ribbon 21. A change in tension is prevented, and thus an appropriate tension is always applied to the thermal transfer ribbon 21. The change of the tension of the ribbon due to the change of the diameter is prevented by an appropriate slip mechanism. The thermal transfer ribbon 21 is
One frame of the receiving material coated with the pretreatment material alone for improving the adhesion of the dye along the conveying direction (length direction),
Next, for example, a total of 4 frames including 3 frames in which dyes are applied in the order of yellow, magenta and cyan (a binder material may be included in the dyes) are set as one set, and a large number of sets are connected in series. Before the printing point where the head 20 and the platen are brought into pressure contact with each other, the recording paper S and the thermal transfer ribbon 21 are pressed in a planar manner by using the curved waist of the recording paper S, and the thermal transfer ribbon 21 is pressed. A pre-pressing means for removing wrinkles, for example, the above-mentioned tension roller 26 is provided. Further, a peeling portion 28 for facilitating peeling of the thermal transfer ribbon 21 from the recording paper S is provided at a lower stage of the pressure contact point between the head 20 and the platen 29 in the thermal transfer ribbon conveyance direction.
A platen 29 is provided so as to face the head 20 and can be pressed against and separated from the head 20. By sandwiching the thermal transfer ribbon 21 and the recording paper S between the head 20 and the platen 29 with an appropriate pressure,
The thermal transfer ribbon 21 is synchronously conveyed from the left to the right in FIG. 1 with respect to the head 20 in accordance with the conveyance speed of the recording sheet S sandwiched between the grid roller 18 and the pinch roller 19.
One frame on the thermal transfer ribbon 21 is thermally transferred. The recording sheet S after the thermal transfer is returned from the right side to the left side in FIG. 1 with respect to the head 20, and the thermal transfer ribbon 21 is advanced one frame, and then the recording sheet S is moved from the left side to the right side in FIG. Direction and carry out thermal transfer.

Then, the platen 29 and the pinch roller 19 are controlled so as to be displaced in the following three stages depending on the conveyance state of the recording paper S. At the time of forming the receiving layer / image (the recording sheet S is conveyed to the head from the left to the right in the drawing), the platen 29 is brought into pressure contact with the head 20, as shown in FIG. At this time, the pinch roller 19 is arranged at a position where the tangent at the contact point with the grid roller 18 also contacts the platen 29.
Make sure that the recording paper S is not folded at any part. When the recording sheet S is returned to the receiving layer / image forming start position (the recording sheet S is conveyed from the right side to the left side of the drawing with respect to the head), as shown in FIG. The platen 29 is separated from the head 20 to prevent it from hitting, and the pinch roller 19 and the grid roller 1
Change the tangential direction at the point of contact with 8. When the recording sheet S is introduced into the receiving layer / image forming mechanism (the recording sheet S is pinched between the pinch roller 19 and the grid roller 18 from the sheet feeding path 5) The recording sheet S is received from the receiving layer / image forming mechanism When ejecting the recording paper S from between the pinch roller 19 and the grid roller 18.
The sheet is discharged to the sheet discharge path 6) It is displaced to an intermediate position between FIG. 6 and FIG. 7 (the platen 29 is in a separated state) to facilitate the introduction and discharge of the recording sheet S and prevent jamming. The take-up reel 24 is driven by the motor 30. The grid roller 18 and the platen 29 are driven by a first drive system including a motor 31, a belt 32, a pulley 33 and the like. The drive control is performed by a control means (not shown) such as a CPU. The sensor 34 positions the start of transfer of the thermal transfer ribbon.

[Structure of Protective Layer Forming Mechanism 4] Next, the protective layer forming mechanism 4 will be described with reference to FIG. A head 35 and a platen 36 are arranged at the end of the paper discharge path 6. The grid roller 37 and the pinch roller 3 are in the lower stage.
And 8 are provided. The platen 36 is separated from the head 35 when the recording paper S is introduced and when the thermal transfer ribbon 43 is independently conveyed. 39 is a feed reel, 40 is a take-up reel, 41 is a roller for feeding a ribbon, and 42 is a tension roller. A torque limiter (not shown) is used for the transport roller 41 and the take-up reel 40 to always apply an appropriate tension to the thermal transfer ribbon 43. Thermal transfer ribbon 4
A transparent material (post-treatment material) that covers and protects the surface of the image on the recording paper S is applied to the sheet 3. A paper discharge roller 46 discharges the recording paper S, for which printing is completed, to the paper discharge tray 8. The take-up reel 40 and the transport roller 41 are driven by a motor 47. The grid roller 37 and the platen 36 are driven by a second drive system such as a motor 48, a belt 49 and a pulley 50. The motor 48 of the second drive system is, as described above, the feeding roller 12, the feeding roller 13 and the registration roller 1 in the paper feeding mechanism 2.
4 is also driven. The drive control is performed by a control means (not shown) such as a CPU. Recording paper S sensor 51
Is for counting the number of printing sheets of the recording paper S.

Next, a control example of the thermal recording means of the present invention will be briefly described with reference to FIG. The image signals (R, G, B) are converted into Y, M, C color signals through a matrix circuit,
It is input to the shift register of the thermal recording means 20 through the image transfer circuit composed of the gradation correction circuit. The gradation correction circuit is composed of a color signal selection circuit, A / D conversion, and a lookup table. In this case, a thermal head is used as the thermal recording means, and the heating elements 20a to 20a are used.
n, an npn transistor, a latch circuit, and a shift register. The output of the matrix circuit is connected to a color signal selection circuit (not shown) of a maximum density detection circuit and a gradation correction circuit. The output of the maximum density detection circuit is also connected to this color signal detection circuit, and the output is connected to the comparison circuit and the image transfer circuit via the A / D conversion circuit and the look-up table. The output is connected to the shift register of the thermal head which is the thermal recording means. The output of the shift register is connected to the latch circuit, and the output of the latch circuit is connected to one input of the AND gate. As for the output of the AND gate, the emitter of the NPN transistor is grounded and the collector is the heating elements 20a to 20b.
Is connected to the power supply terminal V via. This power supply terminal V
The electric potential v of is adjusted by the adjusting means W described above only when printing the receiving layer as shown. The other input of the AND gate is connected to the output of a strobe table (not shown). Three kinds of signals of a load pulse, color data, and a reference clock are input to this strobe table. The load pulse is a signal for resetting the straw table and setting the latch state of the latch circuit. The color signal is a signal source that specifies what is being printed. The reference clock is a clock for calculating the output time of the strobe signal output from the strobe table to each AND gate.

<Operation> The operation of the above apparatus will be described with reference to FIGS. 1 to 7 and the time chart of FIG. By sandwiching one recording sheet S between the separation gate 11 and the paper feed tray 9, the height of the separation gate 11 is adjusted. Next, the recording sheets S are stacked and stored in the sheet feeding tray 9, and the alignment guide 10 is moved to align the bundle of recording sheets S in the lateral direction. On the other hand, this apparatus receives image information obtained by inputting an image from a image scanner (not shown) to a personal computer (not shown), image processing, and information such as the number of printed sheets. Next, the feeding roller 12 is driven to drive the separation gate 11
Is separated into one and sent out. This recording paper S
Passes between the feed rollers 13 in the separated state and hits the registration roller 14 in the stopped state to correct the skew. Next, the recording paper S is conveyed by the feed roller 13 and the registration roller 14 that sandwich the recording paper S, and the switching gate 15 is pushed open to reach between the grid roller 18 and the pinch roller 19. At this time, the recording paper S sensor 17 counts the number of fed sheets. The recording paper S is sandwiched between the grid roller 18 and the pinch roller 19 which are driven, and is fed toward the head. At this time, platen 2
9 and the pinch roller 19 are in the intermediate position between FIG. 2 and FIG. Next, the grid roller 18 is reversed and the recording paper S is moved to the position shown in FIG.
The recording paper S sensor 17 detects the trailing edge of the recording paper S and then counts a predetermined number of pulses to stop the grid roller 18. The transfer roller 13 and the registration roller 14 are positioned to start the transfer of the recording paper S.
It is detected by a recording paper detection sensor provided between and. Next, the motor 30 drives the take-up reel 24 and the conveying roller 25 to position the start of transfer of the top of the receiving material on the thermal transfer ribbon 21. Next, the platen 29 is attached to the recording paper S and the thermal transfer ribbon 2.
The head 1 is sandwiched and pressed against the head 20 to obtain the state of FIG. Next, the take-up reel 24, the conveyance roller 25, and the grid roller 18 are driven to drive the thermal transfer ribbon 21 and the recording paper S.
And the head 20 are heated according to the image information, and a receiving layer is formed on the surface of the recording paper S by thermal transfer. The thermal transfer ribbon 21 includes the head 20 and the platen 2.
The recording sheet S that is curved before reaching the printing point where it is pressed against 9
The recording sheet S and the thermal transfer ribbon 21 are superposed by the waist of the sheet, and are conveyed while being pressed against each other by the tension roller 26. Next, the platen 29 is separated and retracted from the head 20 to obtain the state shown in FIG. 10 Positioning of the thermal transfer start of the recording paper S, positioning of the thermal transfer start of the thermal transfer ribbon, pressure contact of the platen with the head,
The operations of thermal transfer and separation / withdrawal from the platen head are repeated three times to sequentially transfer the yellow, magenta, and cyan dyes to the receiving layer of the recording paper S, and print images such as characters and figures. In addition, while the receiving layer and the image are formed on the first recording sheet S in this manner, the next second recording sheet S is advanced to the position of the registration roller 14 and kept waiting. 11 Next, the grid roller 18 and the feed roller 7 are driven to eject the recording sheet S from the receiving layer / image forming mechanism 3 into the sheet discharge path 6
It is conveyed toward the protective layer forming mechanism 4 via. At this time, the platen 29 is separated from the head 20. While the first recording sheet S is being conveyed through the sheet discharge path 6 as described above, the previously mentioned second recording sheet S is conveyed to the receiving layer / image forming mechanism 3. 12 When the recording paper S sensor 52 detects the leading edge of the recording paper S and counts a predetermined number of pulses, the feeding of the recording paper S is stopped and the protective layer transfer start position is determined. 13 Next, the protective layer transfer start position of the thermal transfer ribbon 43 is set, the platen 36 is pressed against the head 35, the thermal transfer is performed, and the platen 36 is separated and retracted from the head 35 in order, and the protective layer is formed on the surface of the image on the recording paper S. To complete the business card. 14 Next, the recording paper S is ejected to the paper ejection tray 8 by the paper ejection roller 46. While the second recording sheet S is being formed with the receiving layer and the image, the first recording sheet S described above is formed.
Is discharged to the paper discharge tray 8, and the operation of first feeding the third recording paper S from the paper feed tray 9 to the position of the registration roller 14 is performed.

[0017]

According to the present invention, the following effects can be obtained. A control means is provided to adjust the melting amount of the thermal recording means that melts the receiving layer according to the roughness of the paper surface of the recording paper used, the background color of the paper surface, and the like. Since the layer thickness is variably adjusted, the layer thickness of the receiving layer formed on the recording paper can be formed to an appropriate layer thickness suitable for the recording paper, and the recording paper becomes thicker than necessary. Even when the receiving layer is partially formed, the step between the edge of the receiving layer and the recording paper can be suppressed to a small level, and peeling at the stepped portion is hateful, and scratches are also hateful. Further, by making the receiving layer colored such as white and adjusting the layer thickness, the background color of the surface of the recording paper does not float up in the image, and the color of the image can be accurately expressed. Further, since the thickness of the receiving layer can be set to an appropriate thickness according to the recording paper, by selecting a recording paper that can be used in advance, the energy for melting the receiving layer can be suppressed to be small, and the thermal recording The amount of electric power applied to the means is small, and therefore the power supply is inevitably downsized, and a compact image forming apparatus can be provided.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an entire apparatus according to an embodiment of the present invention.

FIG. 2 is an external view showing the entire apparatus according to an embodiment of the present invention.

FIG. 3 is a perspective view showing a part of the embodiment.

FIG. 4 is a print state cross-sectional view of a recording sheet that has been subjected to a print process according to the embodiment.

FIG. 5 is a cross-sectional view of a printing state of a recording sheet that has been subjected to a printing process according to the embodiment.

FIG. 6 is a partial operation state diagram of the embodiment.

FIG. 7 is a partial operation state diagram of the embodiment.

FIG. 8 is a flowchart showing the operation of the embodiment.

FIG. 9 is a control circuit diagram of the embodiment.

[Explanation of symbols]

 S recording paper W control means 20 thermal recording means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location 8305-2H B41M 5/26 H

Claims (4)

[Claims] 1. Before image formation, after forming a receiving layer for receiving the image-forming dye melted by the heat-recording means in at least the image-forming area of the supplied recording paper, the image-forming dye is heated in the heat-recording means. In an image forming method of forming an image by selectively heating the image forming dye into the image forming area by means of a heating method, the melting amount of the thermal recording means for melting the receiving layer is adjusted according to the recording paper used. The thickness of the receiving layer is adjusted by bleeding, the receiving layer is appropriately melted by the thermal recording means according to the supplied recording paper, the molten receiving layer is transferred to the recording paper, and the layer thickness of the receiving layer is variably adjusted. Image forming method. 2. Before image formation, after forming a receiving layer for receiving the image forming dye melted by the heat recording means in at least the image forming area of the supplied recording paper, the image forming dye is heated by the heat recording means. In an image forming apparatus that selectively heats the image forming dye to transfer the image forming dye into the image forming area to form an image, the melting amount of the thermal recording means for melting the receiving layer is adjusted according to the recording paper used. The image forming apparatus is characterized in that the layer thickness of the receiving layer is variably adjusted according to the supplied recording paper. 3. The control means can adjust the melting amount of the thermal recording means according to the roughness of the recording surface of the recording paper to be used, and the layer thickness of the receiving layer can be adjusted according to the roughness of the recording surface of the recording paper. The image forming apparatus according to claim 2, wherein the image forming apparatus is variable. 4. The control means is capable of adjusting the melting amount of the thermal recording means according to the background color of the recording paper to be used, and varying the layer thickness of the receiving layer according to the background color of the recording paper. The image forming apparatus according to claim 2.