JPH067952U - Color thermal transfer recording device - Google Patents

Abstract

(57) [Summary] [Purpose] Stable printing is always obtained regardless of the environment. [Structure] Before the recording paper 1 reaches the printing portion of the TPH (thermal head) 7, a preheat portion 5 is provided to make the moisture absorption of the recording paper 1 constant, and the characteristics of the recording paper 1 are stabilized before printing. Configured to measure. [Effect] Since the characteristics of the recording paper are made uniform before printing, shrinkage due to heat does not occur during printing (when TPH is heated).
It is possible to prevent print misalignment due to superposition of M and C three colors.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a color thermal transfer recording device.

[0002]

[Prior art]

 Conventionally, a color thermal transfer recording apparatus heats a heating resistor portion of a thermal head (hereinafter referred to as TPH) arranged on a platen to melt the ink of an ink sheet located below TPH to thereby perform recording paper. Is being transferred to.

After the recording paper is fed from the paper feed section, it is wrapped around a platen, which is usually made of rubber, and ink sheets of almost the same width are overlapped from above, pressing TPH and applying heat to melt the ink, Transfer is performed in order of (Y), magenta (M), and cyan (C). Generally, after printing one color, the recording paper is rewound and the next color is overlaid and printed. At this time, since the recording paper is first heated by the heat-generating resistor portion of the TPH, there is a phenomenon that the water evaporates due to the heat from the state where the recording paper was expanded and the heat shrinks.

Shrinkage is large during printing of the first color and decreases after the second color. For this reason, the recording paper contracts after printing one color, and the recording paper length when printing differs from the recording paper length when returning. Even if the recording paper is returned by the same amount as when printing, printing does not return to the same position. There was a phenomenon that they did not overlap.

[0005]

[Problems to be solved by the device]

 However, in the conventional recording apparatus, the recording paper receives heat only at the heat generating resistor portion of TPH. Generally, recording paper having a thickness of 60 to 120 μm is used. Therefore, water is contained to some extent, and contraction occurs due to heat generation of the heat generating resistor portion of TPH. Generally, in the case of a color thermal transfer recording apparatus, it is general to rewind the recording paper for each color printing and print it by superposing it on the recording paper. Three colors of Y, M, and C are piled up to produce black. Therefore, if the amount of return of the recording paper after printing each of the three colors of Y, M, and C is different, the three colors do not overlap and the colors shift. There was a problem that so-called misregistration occurred, where originally what should have been black turned yellow or reddish, and high-quality printing could not be obtained. Further, since the moisture content of the recording paper varies depending on the environment (especially humidity), the shrinkage of the recording paper is large at high humidity and small at low humidity, so that there is a problem that the amount of print misalignment depends on the environment.

Therefore, an object of the present invention is, in order to solve such a conventional problem, to heat the recording paper in advance to dry it so as to eliminate the contraction at the time of printing and reduce the print misalignment. , To obtain stable printing.

[0007]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, before the recording paper reaches the lower part of the heat generating resistor of the TPH and receives heat, the recording paper is preheated to evaporate the water content in the recording paper, and the composition of the recording paper is reduced. The printing operation is performed after stabilizing the.

[0008]

[Action]

 According to the color thermal transfer recording apparatus configured as described above, since the composition of the recording paper is constantly evaporated by evaporating the moisture of the recording paper before starting the printing operation, there is no contraction of the recording paper due to the heat of the heating resistor of TPH. If you return the same amount as the recording paper feed amount when printing, the recording paper will return to the same position. For this reason, there is almost no printing deviation in the three colors of Y, M, and C. Also, since the composition of the recording paper is always constant even in different environments, stable printing can be obtained even in high humidity.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, recording paper 1 is cut paper and is accommodated in a paper feed cassette 2 in an overlapping manner. A sheet feeding roller 3 is a sheet feeding roller that is rotated by a driving device (not shown) and separates and feeds the recording sheets 1 stacked in a sheet feeding cassette one by one.

Reference numeral 4 is a recording paper guide for feeding the recording paper 1 to the printing unit. A preheat section 5 is provided below the recording paper guide 4. The preheating section 5 is designed to generate heat of about 60 ° C. at a portion for preheating the recording paper 1. A platen 6 is a roller having a central portion made of metal and a peripheral portion made of rubber. Reference numeral 8 denotes a capstan roller, which is made of metal and has particles formed by thermal spraying on the surface so as to grip the recording paper 1. A pinch roller 9 is made of rubber and is in pressure contact with the capstan roller 8. After passing through the recording paper guide 4, the recording paper 1 is wrapped around the platen 6, passed through the feeding side recording paper guide 10, and then sandwiched by the capstan roller 8 and the pinch roller 9 to be gripped.

A driving pulley (not shown) is integrally attached to one end of the capstan roller 8. The capstan roller 8 is also driven by a driving stepping motor (not shown) in the forward direction and the reverse direction. The stun roller 8 is driven. The recording paper 1 is gripped and reciprocated by the capstan roller 8 and the pinch roller 9. Reference numeral 11a is a supply roll for the ink sheet 11, and although not shown, a frame holds both ends of the core of the roll, and although not shown, a mechanism for applying back tension is provided.

Reference numeral 11 is an ink sheet on which ink is applied in the order of yellow (Y), magenta (M), and cyan (C), and is supplied from a supply roll 11a and wound by a winding roll 11b. There is. Although not shown, a driving pulley is integrally attached to one end of the ink sheet take-up roll 11b, and although not shown in the figure, the ink sheet 11 is taken up by the rotation of the DC motor.

Reference numeral 7 is a thermal head (TPH), which is configured to move vertically with respect to the platen 6 by a drive mechanism (not shown). Only during printing, the platen 6 is pressed with a predetermined pressure, heat is applied if necessary, the ink of the ink sheet 11 is melted, and transferred to the recording paper 1.

Next, the operation will be described. The recording paper 1 is separated from the paper feed cassette 2 by the paper feed roller 3 and sent out one by one. When the recording paper 1 sent out passes through the preheat section 5, the moisture absorption can be dried by heat of about 60 ° C. and the shrinkage due to heat can be made constant. In this state, the TPH 7 is separated from the platen 6 and the ink sheet 11 is taken up to perform cueing by driving a motor.

Although not shown, detection marks are printed on the front portions of Y, M, and C of the ink sheet 11 so that they can be detected by a sensor (not shown). When the first color (Y) of the ink sheet 11 is finished, the TPH 7 is elastically pressed against the platen 6 to heat the heating resistor portion (not shown) to melt the ink of the ink sheet 11 and The transfer is performed on top.

At the same time when the printing operation is started, the ink sheet 11 is cued, and the TPH 7 is pressed against the platen 6 with a predetermined pressure to be energized, and the heating resistor generates heat to cause the ink on the ink sheet 11 to be heated. Is melted and transferred to the recording paper 1. Since the recording paper 1 has been preliminarily absorbed and contracted by the preheat section 5, the recording paper 1 does not contract due to heat applied during printing. Therefore, the contraction at the time of printing each color of Y, M, and C is eliminated, and even if the same amount of paper feed amount as that at the time of one color printing is returned, it returns to the same position, so that there is no printing deviation.

Further, although not shown, as another embodiment, there is a means for preheating the recording paper by the heat of the heat generating portion (eg, power supply) in the apparatus.

[0018]

[Effect of device]

 As described above, according to this invention, the moisture content in the recording paper can be kept constant by adopting a structure in which the recording paper is preheated before it reaches the heating resistor portion of the TPH. . For this reason, the shrinkage due to the change in the water content of the recording paper after printing is reduced, and the recording paper feed amount at the time of printing and the feed amount at the time of returning are the same for each color. Therefore, Y, M, and C color printing overlaps, stable printing can be performed regardless of the environment, and a thermal transfer recording apparatus with high image quality can be provided, and its industrial utility value is extremely large.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of a color thermal transfer recording apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 1 Recording paper 5 Preheat part 6 Platen 7 Thermal head 11 Ink sheet

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location 8906-2C B41J 3/20 110

Claims (1)

[Scope of utility model registration request] 1. A color thermal transfer recording apparatus for recording an image with a heat-meltable ink sheet and a thermal head, wherein a preheating section for maintaining a constant moisture absorption of the recording sheet is provided between a sheet feeding section and the thermal head. A color thermal transfer recording device characterized by the above.