JPH04173370A - Ink sheet for thermal transfer recorder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an ink sheet used for example in a thermal transfer recording device, and more particularly relates to an improvement of an ink sheet in which a plurality of colors are arranged in a sequential manner. .

(Prior Art) As is well known, a conventional thermal transfer recording device uses an ink sheet that is transported in a fixed direction at a predetermined speed by an ink sheet supply roll, and an ink sheet that is wound around a platen roller and transported in the same direction at a predetermined speed. These ink sheets and image-receiving sheets are sandwiched between a platen roller and a thermal head that generates a thermal pattern according to the image recording information, and the ink on the ink sheets is selectively transferred to create an image. In the configuration in which information is transferred to image-receiving paper, the ink sheet can be used at high density by setting the transport speed of the ink sheet to the transport speed of the image-receiving sheet at a speed ratio of 1:n (n>I). A thermal transfer type recording device has been developed that is configured to save energy consumption, reduce the frequency of replacement, and reduce running costs.
(See Publication No. 2-58917). FIG. 5 shows the image density characteristics of an ink sheet that can be recorded when the transport speed ratio of the ink sheet and the image receiving sheet is 1:n (n≧1). It can be seen that even when the speed ratio V p /V l of the conveying speed V of the image receiving sheet to the conveying speed V1 of the ink sheet is changed from 1 to n, the difference Δ in image density is very small.

By the way, as the winding diameter of the ink sheet supply roll and the ink sheet take-up roll gradually changes, the conveyance speed of the ink sheet changes, so the ink width of each ink sheet needs to be wide in the parts where the conveyance speed is high. On the other hand, in areas where the conveyance speed is slow, a narrow one is sufficient.

However, in the case of ink sheets used in such conventional thermal transfer recording devices, in which multiple colors are arranged in plane sequential order, the pitch of each color arrangement is set to be equal, so the speed is There was a problem in that the ink sheet was wasted in areas where the printing speed was slow.

(Object of the Invention) The present invention has been made in view of the above-mentioned problems, and is an ink sheet used in a thermal transfer recording device that can eliminate waste in an ink sheet in which a plurality of colors are sequentially arranged. The purpose is to provide a simple solution.

(Structure of the Invention) In order to achieve the above object, the present invention provides an ink sheet on which heat sublimation type or heat melting type ink is supported and a plurality of colors arranged in a plane-sequential manner; an ink sheet supply roll, an ink sheet take-up roll that winds up the ink sheet fed out from the ink sheet supply roll at a predetermined speed, and an ink sheet winding roll disposed between the ink sheet supply roll and the ink sheet take-up roll; A platen roller for conveying the image receiving sheet overlapped with the ink sheet in the opposite direction at a constant speed or a different speed; and a platen roller that sandwiches the ink sheet and the image receiving sheet and responds to the image information. A thermal transfer recording device is provided with a thermal head that selectively transfers ink from an ink sheet to an image-receiving sheet by generating a thermal pattern, wherein the conveying speed ratio of the ink sheet and the image-receiving sheet is I+n (n≧ 1) A drive mechanism for an ink sheet supply roll and a drive mechanism for a platen roller that transport each ink sheet supply roll separately, and an ink sheet supply roll that is provided on the ink sheet supply roll and applies a braking force in a direction opposite to the rotational direction of the ink sheet supply roll. and a tension applying mechanism that applies a predetermined tension to the ink sheet, and when the ratio of the outer diameter to the inner diameter of the ink sheet take-up roll is m: I (m>1), the ink sheet is man. The color pitch of the sheet is characterized by gradually increasing as it is used.

Further, an ink sheet carrying heat sublimation type or heat melting type ink and having a plurality of colors arranged in a plane-sequential manner, and an ink sheet supply roll around which this ink sheet is wound;
An ink sheet winding roll that winds up the ink sheet sent out at a predetermined speed from the ink sheet supply roll while applying a predetermined tension, and an ink sheet winding roll disposed between the ink sheet supply roll and the ink sheet winding roll. A platen roller for conveying the image receiving sheet in the same direction at the same speed or at different speeds while superimposed on the ink sheet, and this platen roller holds the ink sheet and the image receiving sheet and conveys the image information. A thermal transfer recording device is provided with a thermal head that selectively transfers ink from an ink sheet to an image-receiving sheet by generating a thermal pattern according to An ink sheet supply roll drive mechanism and a platen roller drive mechanism are provided for transporting the ink sheet supply rolls separately so that n (n≧1), and the ratio of the outer diameter to the inner diameter of the ink sheet supply roll is m:l. When (m>1), m≦n, the color pitch of the ink sheet is characterized in that it gradually becomes shorter as it is used.

The present invention will be described in detail below based on preferred embodiments shown in two drawings.

FIG. 1 shows an embodiment of a thermal transfer type recording device according to the present invention. 1, an ink sheet supply roll 3 on which this ink sheet 1 is wound in a roll shape, an ink sheet winding roll 5 that winds up the ink sheet 1 sent out at a predetermined speed from this ink sheet supply roll 3, and these A drum-shaped drum disposed between the ink sheet supply roll 3 and the ink sheet take-up roll 5 and for conveying the image receiving sheet 7 in the opposite direction with the ink sheet 1 overlapped with the ink sheet 1 at the same speed or at different speeds. The ink sheet 1 and image-receiving sheet 7 are held between the platen roller 9 and the ink sheet 1 is selectively dotted onto the image-receiving sheet 7 by generating a heat pattern according to the image information. Thermal head 11, which can be moved up and down by a lifting mechanism (not shown), and the thermal head 11
The image forming apparatus is provided with a pressing mechanism such as a spring 13 that presses the image onto the platen roller 9 via the ink sheet l and the image receiving sheet 7. The leading end of the image receiving sheet 7 is held by a clamper 15 provided on the platen roller 9 and is wound around the outer periphery of the platen roller 9 .

The ink sheet supply roll 3 is equipped with a torque limiter 17 composed of an electromagnetic powder clutch, a friction clutch, etc.
(tension applying mechanism) is connected. Torque limiter 1
Reference numeral 7 constitutes a tension applying mechanism that applies a braking force in a direction opposite to the rotating direction of the ink sheet supply roll 3 to apply a predetermined tension to the ink sheet 1.

Further, the ink sheet take-up roll 5 is connected to a drive 119 composed of a stepping motor, a speed reducer, etc., and by driving the drive mechanism 19, the ink sheet take-up roll 5 is rotated at a constant angular velocity ω. The ink sheet 1 is wound up at a predetermined speed V1.

Furthermore, a drive mechanism 21 composed of a stepping motor, a speed reducer, etc. is connected to the platen roller 9, and by driving the drive mechanism 21, the platen roller 9 is rotated at a constant speed, and only the image receiving sheet 7 is rotated. ■ At a predetermined speed in the opposite direction to the ink sheet 1. It is configured to be transported by

The ink sheet 1 and the image-receiving sheet 7 have surface layers that have slipperiness and #11 releasability so that they can freely slide relative to each other, and their maximum static friction coefficient is the same as that between the image-receiving sheet 7 and the platen roller 9. This is because the coefficient of dynamic friction is set smaller than that of . Therefore, the image-receiving sheet 7 is brought into contact with the platen roller 9 along with the ink sheet I by the pressing force of the ribs 13 and the thermal head 11, and the platen is brought into contact with the platen roller 9 by the frictional force generated between the platen roller 9 and the image-receiving sheet 7. When the roller 9 rotates at a predetermined circumferential speed, only the image receiving sheet 7 is conveyed at that circumferential speed.

The color pitch of the ink sheet 1 gradually becomes longer as it is used, as shown in FIG. 2, for example. That is,
The ink sheet 1 has the shortest ink width along the transport direction of the first color (yellow (Y) in this embodiment) at the beginning of use, and gradually becomes longer as it is used, and the ink width of the first color (yellow (Y) in this embodiment) is the shortest at the beginning of use. In the example, the ink width of cyan (C) is the longest.

Here, the first color (
Y) color pitch p. , the final color at the end of use (
If the coloring pitch of C) is ρ, the coloring pitch p0 of the first color (Y) is po'' flood/n o +a and pr=flood/n++a. However, I!, is one of the image receiving sheets 7 The length of the recording screen, a, is a margin that is arbitrarily set.

Therefore, po is the length of one screen when the ink sheet 1 is transported at the speed rnoω, and p+ii is the length of the screen bone when the ink sheet 1 is transported at the speed rR+ω. The color pitch of the ink sheet 1 becomes longer from p. to pl as the conveyance speed V1 of the ink sheet increases to 8.■.

The drive mechanism 19 for the ink sheet salt roll 5 and the drive mechanism 21 for the platen roller 9 are configured so that the ink sheet supply roll 3 rotates at a circumferential speed smaller than the circumferential speed of the platen roller 9 during image recording. The speed ratio of the image receiving sheet 7 is set in advance to be 1:n (n≧1), and the ink sheet 1 is utilized in a high density to save consumption and reduce the frequency of replacement, thereby reducing running costs. ing. Further, when the ratio of the outer diameter to the inner diameter of the ink sheet take-up roll is m:1 (m>1), it is configured such that m≦n.

In addition, the ink sheet l sent out from the ink sheet supply roll 3 has an inner diameter (radius at the start of use) of the ink sheet supply roll 3 of rpa,
If the outer diameter (radius at the end of use) is rp+ and the angular velocity is ω, the conveyance speed at the beginning of use is r2°ω, and the conveyance speed at the end of use is r5ω.

At this time, the inner diameter rvo, outer diameter rFl, and angular velocity ω of the ink sheet take-up roll 3 are r pIta) = V e / n l≦V.

and r p o ω= V s / no≧V p /
Since n, 5 1≦n+<no≦n and ] < r p+/r Fl= no/n +
It is set to satisfy Equation 50.

Next, the action will be explained.

In the above configuration, the image receiving sheet 7 is wound around the outer periphery of the platen row 59, and after the image receiving sheet 7 is conveyed to a predetermined recording start position by rotating the platen roller 9, the thermal head 11 is inserted into the platen opening 9. It is pressed and recording starts.

Here, the conveyance speed of the ink sheet 1 changes because the winding diameters of the ink sheet supply roll 3 and the ink sheet take-up roll 5 gradually change.

Since the ink sheet 1 gradually becomes longer as it is used, it widens in areas where the transport speed is high and narrows in areas where the transport speed is slow.
There will be no idleness.

Note that the present invention is not limited to the above embodiment, and the ink sheet 1 and the image receiving sheet 7 are conveyed in the same direction, and the torque limiter 17 provided on the ink sheet supply roll 3 is connected to the ink sheet take-up roll. 5, and the color pitch of the ink sheet may be configured to gradually become shorter as it is used (see Fig. 5).

In this case, the ink sheet 1 sent out from the ink sheet supply roll 3 is, for example, as shown in FIG.
゜, the inner diameter (radius at the end of use) is rt++, and the angular velocity is ω, then the conveyance speed at the beginning of use is rRoω
, the conveyance speed at the end of use is r'+++ω.

At this time, the outer diameter r8°, inner diameter r'+++, and angular velocity ω8 of the ink sheet supply roll 5 are rpoω=V p /
n 6≦Vp and r' R1ω” V p / n l ≧v p
/ n, so l≦no <n+≦n and 1 < r RO/ r RI= n + / no
It is set to satisfy the expression ≦n.

(Effects of the Invention) As explained above, according to the ink sheet used in the thermal transfer recording device of the present invention, when the ink sheet and the image-receiving sheet are conveyed in opposite directions, the color pitch of the ink sheet gradually changes. Since the ink sheets are long and gradually become shorter when they are in the same direction, waste of the ink sheet can be removed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a thermal transfer recording apparatus using an ink sheet according to an embodiment of the present invention, FIG. 2 is a perspective view showing an ink sheet and a recording screen of an image receiving sheet according to an embodiment, and FIG. 3 is a diagram showing the outer diameter and inner diameter of the ink sheet take-up roll, FIG. 4 is a perspective view showing the recording screen of the ink sheet and image receiving sheet according to another embodiment, and FIG. 5 is a diagram showing the conveyance speed of the image receiving sheet. FIG. 3 is a correlation diagram between the speed ratio V p /V 1 and the image density with respect to the conveyance speed V of the ink sheet of V. FIG. ■... Ink sheet, 3... Ink sheet supply roll, 5... Ink sheet take-up roll, 7... Image receiving sheet, 9... Platen roller, 11... Thermal head, 19...・Drive mechanism (drive mechanism for ink sheet supply roll), 21... Drive mechanism (drive mechanism for platen roller) Patent applicant: Ricoh Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (2)

[Claims] (1) An ink sheet carrying heat sublimation type or heat melting type ink and having a plurality of colors arranged in a plane-sequential manner, and an ink sheet supply roll around which this ink sheet is wound;
An ink sheet winding roll that winds up the ink sheet sent out at a predetermined speed from the ink sheet supply roll, and an ink sheet winding roll that is disposed between the ink sheet supply roll and the ink sheet winding roll, and that rolls the image receiving sheet between the ink sheet and the ink sheet. The ink sheet and the image receiving sheet are sandwiched between the platen roller and the platen roller for conveying the ink sheet and the image receiving sheet in opposite directions at the same speed or different speeds in an overlapping state, and a heat pattern corresponding to image information is generated. A thermal transfer recording device equipped with a thermal head that selectively transfers ink from an ink sheet to an image receiving sheet, the conveying speed ratio of the ink sheet and the image receiving sheet being 1:n.
an ink sheet supply roll drive mechanism and a platen roller drive mechanism that convey each ink sheet supply roll separately so that (n≧1); and a tension applying mechanism for applying a predetermined tension to the ink sheet, and the ratio of the outer diameter to the inner diameter of the ink sheet take-up roll is m:1 (m
>1), where m≦n, an ink sheet used in a thermal transfer recording device, wherein the color pitch of the ink sheet gradually becomes longer as it is used. (2) an ink sheet carrying heat sublimation or heat melting ink and having a plurality of colors arranged in a plane-sequential manner, and an ink sheet supply roll around which this ink sheet is wound;
An ink sheet winding roll that winds up the ink sheet sent out at a predetermined speed from the ink sheet supply roll while applying a predetermined tension, and an ink sheet winding roll disposed between the ink sheet supply roll and the ink sheet winding roll. A platen roller for conveying the image-receiving sheet in a superimposed state with the ink sheet in the same direction at a constant speed or at different speeds; and a platen roller that sandwiches the ink sheet and the image-receiving sheet and responds to the image information. A thermal transfer recording device comprising a thermal head that selectively transfers ink from an ink sheet to an image receiving sheet by generating a thermal pattern, wherein the conveying speed ratio of the ink sheet and the image receiving sheet is 1:n.
It is equipped with an ink sheet supply roll drive mechanism and a platen roller drive mechanism that convey each ink sheet supply roll separately so that (n≧1), and the ratio of the outer diameter to the inner diameter of the ink sheet supply roll is m:1 ( An ink sheet for use in a thermal transfer recording device, wherein m≦n when m>1), wherein the color pitch of the ink sheet gradually becomes shorter as it is used.