JP2002052749A - Method of transfer printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of transfer printing wherein on-demand printing is performed by using a phase change ink which changes to a solid, a malleable material having a high viscosity or a liquid by a different temperature, does not include a solvent such as toluene, is not volatile and is less toxic than an oil-based ink so that the printing is friendly to organisms and the living environment, and the printing speed is high and the printing can be sufficiently applied for practical use. SOLUTION: Each of an ink tray 3 and an inking roll group 8 is maintained in a high temperature so that the phase change ink 4 is maintained in a liquid condition and the phase change ink 4 in the liquid condition reserved in the ink tray 3 is coated on a transfer roller 1 to form a uniform solid film with a thickness of a few micrometers made of the phase change ink 4 by being quickly cooled. A heat light beam is emitted or not emitted to the solid film in accordance with image data to be printed by a heat light beam emitting/liquefied image forming apparatus to instantly liquefy the solid film at a portion where the heat light beam is emitted and then a positive liquefied image is formed. The positive liquefied image is transferred to be printed on a printing web 12 inserted between the transfer roller 1 and an impression cylinder 2. The residual solid film stuck to the transfer roller 1 remaining after the printing is heated to be liquefied and is squeezed by means of a doctor 14 to be collected to the ink tray 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a solid (eg, about 30 ° C. or less), highly viscous malleable substance (eg, about 30 ° C.) depending on temperature.
40 ° C. to about 80 ° C.), liquid (eg, 90 ° C. to about 160 ° C.), non-volatile, low-toxicity phase-change ink that does not contain a solvent such as toluene (sometimes a room temperature solid ink, Transfer printing method capable of performing on-demand printing using hot melt ink). The present invention also relates to a transfer printing method which does not contain a highly toxic solvent such as toluene and is friendly to living organisms and living environments, has a high printing speed, and is sufficiently practical.

[0002]

2. Description of the Related Art Conventionally, on-demand printing is performed by an ink jet printer or a laser printer. Inkjet printers have been provided for printing using phase change ink.

[0003]

In any of offset printing, letterpress printing, and intaglio printing, on-demand printing is impossible because it is necessary to make a plate and to replace the plate. For offset printing, a computer tow plate has been realized, but on-demand printing has not been possible. Due to the Chemical Substance Management Promotion Act, which is a toxic substance control law, the so-called PRTR method, the ban on the use of oil-based inks containing a large amount of highly toxic solvents such as toluene is imminent. Being able to use it is urgent. However, although the water-based ink is used in gravure printing, research is underway to make transferability to a film, image reproducibility, and printing speed equal to those when using an oil-based ink. Therefore, apart from research on aqueous inks, practical research on non-volatile inks containing no solvent such as toluene has been a challenge.

The present invention provides a phase change ink which changes into a solid, a highly viscous malleable substance or a liquid depending on the temperature, is non-volatile and contains no solvent such as toluene, and has extremely low toxicity compared to an oil-based ink. An object of the present invention is to provide a transfer printing method capable of performing on-demand printing by using the method. Another object of the present invention is to provide a transfer printing method that does not contain a highly toxic solvent such as toluene and is friendly to living organisms and living environments, has a high printing speed, and is sufficiently practical.

[0005]

According to a first aspect of the present invention, an inking means for applying ink to a transfer roll in a uniform thin film and an ink tray are maintained at a high temperature at which the phase change ink is maintained in a liquid state. A liquid phase change ink stored in an ink tray is applied to a transfer roll to form a uniform solid film made of the phase change ink, and an image to be printed by a heat ray irradiation liquefied image forming apparatus provided outside the transfer roll. Based on the data, the solid coating is flashed and irradiated with a heat ray to instantaneously liquefy the heat ray irradiated portion of the solid coating to form a positive liquefied image, and the positive liquefied image is transferred between the transfer roll and the impression cylinder. It is an object of the present invention to provide a transfer printing method characterized by transferring and printing on a web to be printed passed through. The second invention of the present application is directed to a method of inking means for applying ink to a transfer roll in a uniform thin film and maintaining a high temperature at which the phase change ink is maintained in a liquid state, and a liquid phase stored in the ink tray. The change ink is applied to a transfer roll to form a uniform solid film made of the phase change ink, and the heat ray is irradiated on the solid based on image data to be printed by a heat ray irradiation liquefied image forming apparatus provided outside the transfer roll. A flash light is applied to the coating to instantaneously liquefy the heat-irradiated portion of the solid coating to form a positive liquefied image, and the positive liquefied image is applied to a printing web passed between a transfer roll and an impression cylinder. Transfer, print,
Thereafter, the present invention provides a transfer printing method characterized in that the remaining solid film adhered to the transfer roll is heated and liquefied, scraped by a doctor and collected in an ink tray.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A transfer printing method according to an embodiment of the present invention will be described with reference to FIG. In the figure, 1
Denotes a transfer roll, 2 denotes an impression cylinder, and 3 denotes an ink tray. Reference numeral 4 denotes a phase change ink stored in the ink tray 3. As the phase change ink 4, one described in JP-A-11-349877 is preferably used. Such phase change inks comprise a component selected from the group consisting of a thermally reversible Diels-Alder polymerization reaction product, a Diels-Alder polymerization precursor, and mixtures thereof, from about 90 ° C to at least about 160 ° C. A liquid having a low molecular weight and a low viscosity at a temperature within the range of from about 40 ° C. to about 8
At temperatures in the range of up to 0 ° C., it becomes a highly viscous malleable material and is thermally reversible between the liquid and solid states, and at temperatures below about 30 ° C. it becomes a solid with polymer properties. The main composition of the phase change ink provided by Phaser Printing, Japan Co., Ltd. consists of a phase change carrier composition comprising a phase change compatible colorant and a monoamide wax and a tetraamide resin. Other modifiers include tackifiers such as hydrogenated glycerin abietic acid which are compatible with fatty acid amides, plasticizers such as phthalate esters, and antioxidants which prevent discoloration of ink. 5 is a high temperature at which the phase change ink 4 is maintained in a liquid state, specifically 9
Ink tray 3 at 0 ° C to 110 ° C (up to 130 ° C)
A heater 6 for heating the ink supply roll, which is located in the ink tray 3 and is driven to rotate, and 7 is located in the ink tray 3 and is always in close contact with the ink supply roll 6 regardless of a change in the ink level. A furnisher roll 8 for rotating and kneading the ink; an ink supply roll 8 for supplying ink from the ink supply roll 6 and finally applying a uniform ink film of several microns to the transfer roll 1;
Is the high temperature at which the phase change ink is maintained in a liquid state, specifically 9
A lamp for heating the inking roll group 8 to 0 ° C. to 110 ° C. (up to about 130 ° C.) is a heat retaining wall. 1
Reference numeral 1 denotes a heat ray irradiation liquefied image forming apparatus, for example, a heat ray emitting means 10a such as a yag laser, an excimer laser, a carbon dioxide gas laser, or a high power semiconductor laser for emitting a heat ray based on image data to be printed; A modular 10b for passing and blocking the light beam, a polygon mirror for scanning the flashing heat beam in the generatrix direction of the transfer roll 1,
And a heat beam scanning means 10c such as a galvanomirror.
When a high-power semiconductor laser is used, the module 10b is unnecessary because it can emit light by blinking. Further, the heat ray irradiation liquefied image forming apparatus 11 may be provided with an array of light emitting elements arranged in a plurality of arrays in the generatrix direction of the transfer roll 1 and performing a delay process to emit heat ray energy in the vicinity of the transfer roll 1. good. 12 is an ink tray liquid phase change ink 11
Is a web to be printed passed between the transfer roll 1 and the impression cylinder 2, 13 is a cold air device for rapidly solidifying the phase change ink transferred and printed on the web to be printed 11 by applying cool air, 14 is a doctor, 15 Is set at a high temperature at which the phase-change ink is maintained in a liquid state, specifically 90 ° C. to 110 ° C. (13 ° C.
The lamp is heated to about 0 ° C.), and 16 is a heat insulating wall.
In addition, in order to apply the liquid phase change ink 4 to the transfer roll 1 and rapidly solidify it, a belt-like body through which a refrigerant is passed is transferred between the application location of the phase change ink 4 and the heat ray irradiation liquefied image formation location. It may be installed close to the roll 1. Also, lamp 9,
Instead of 15, hot air may be applied. In addition,
As the inking means for applying the ink to the transfer roll in a uniform thin film, an inking roll group may be used instead of the inking roll group 8.

According to the transfer printing apparatus having the above structure, the ink tray 3 and the inking roll group 8 are maintained at a high temperature at which the phase-change ink is maintained in a liquid state, and the liquid phase-change ink 4 stored in the ink tray 3 is discharged. It is applied to the transfer roll 1 and rapidly solidified to form a uniform solid film of several microns composed of phase change ink. The solid light film is heated based on image data to be printed by the heat ray irradiation liquefaction image forming apparatus 11. A flash is applied to the solid coating to instantaneously liquefy the heat-irradiated portion of the solid coating to form a positive liquefied image, and the positive liquefied image is passed between the transfer roll 1 and the impression cylinder 2 to be printed. The phase change ink transferred and printed on the web 12 and then transferred and printed on the web to be printed 11 is rapidly solidified by applying the cool air blown out from the cooling air device 13, while the remaining ink in close contact with the transfer roll 1 after printing is applied. Solid coating The scraped with a doctor 14 and heated and liquefied by the lamp 15 is collected in the ink pan 3.

[0008]

According to the transfer printing method of the present invention, the following effects can be obtained. (1) Since a plate is not required, the printing cost is reduced and the printing can be performed quickly, and it can be applied to both low-volume printing and large-volume printing of other types to perform ultimate on-demand printing. (2) Since it uses phase change ink, it does not contain solvents such as toluene or alcohols and is non-volatile and contains a very low-toxic base material. It is not only unregulated but also preferred in the enforcement of the law. (3) Since the phase-change ink is non-volatile, the ink concentration is more than twice as high as that of the oil-based ink, so it is necessary to apply a liquid phase-change ink to the transfer roll and solidify it even if it is several microns. Printing density is obtained, and an ink film thickness equivalent to the ink film thickness of offset printing can be realized.
(Color variation) is reduced, and the phase change ink is less bleeding, so that the effect of high definition is large. In addition, the amount of ink used is small and the cost is low. (4) The beam diameter of the heat beam laser that can be used is 5 μm, so that ultra-high-definition print images exceeding 2000 dpi can be obtained, and since phase change ink is used, solvents such as toluene and alcohols , And is non-volatile, so that the quality of the ink does not change and the printing accuracy does not decrease even after the printing time has elapsed. (5) Heating and drying are not required for solidifying the printed phase change ink, so that thermal energy can be greatly reduced and it is economical. (6) The speed at which the phase change ink solidifies by blowing cold air onto the phase change ink printed on the web to be printed can be dramatically increased, and the printing speed can be increased to about 300 m / min. (7) The solidification of the printed phase change ink does not require heating and drying, and solidifies very quickly, so that the printing target web can be run in a horizontal plane without running up and down, and can be printed. Machine can be lowered. (8) The use of a pigment ink of 1 μm as the phase change ink has a great effect when the plate is made high definition.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a main part of a transfer printing apparatus that performs a transfer printing method according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Transfer roll, 2 ... Impression cylinder, 3 ... Ink tray, 4 ... Phase change ink, 5 ... Heater, 6 ...
・ Ink supply roll, 7 ... Fanisher roll, 8
... Inking roll group, 9 ... Ramp, 10 ...
・ Insulation wall, 11 ・ ・ ・ Heat ray irradiation liquefied image forming apparatus, 1
0a: heat ray emitting means, 10b: modular, 1
0c: heat ray scanning means, 12: web to be printed,
13 ... cold air device, 14 ... doctor, 15 ...
Lamp, 16 ... heat insulation wall

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tatsuo Shigeta 1201-11 Takada, Kashiwa-shi, Chiba F-term in Sink Laboratory Co., Ltd. (reference) 2C065 AB02 CA03 CA10 CA11 CZ16

Claims (2)

[Claims] 1. An inking means for applying ink to a transfer roll in a uniform thin film form, and a liquid phase change ink stored in an ink tray while maintaining an ink tray at a high temperature at which the phase change ink is maintained in a liquid state. Is applied to a transfer roll to form a uniform solid film made of phase change ink, and a heat ray is applied to the solid film based on image data to be printed by a heat ray irradiation liquefied image forming apparatus provided outside the transfer roll. Blinking irradiation instantaneously liquefies the heat-irradiated portion of the solid coating to form a positive liquefied image, and transfers the positive liquefied image to a printing web passed between a transfer roll and an impression cylinder. A transfer printing method characterized by printing. 2. An inking means for applying ink to a transfer roll in a uniform thin film form and a liquid phase change ink stored in an ink tray while maintaining the ink tray at a high temperature at which the phase change ink is maintained in a liquid state. Is applied to a transfer roll to form a uniform solid film made of phase change ink, and a heat ray is applied to the solid film based on image data to be printed by a heat ray irradiation liquefied image forming apparatus provided outside the transfer roll. Blinking irradiation instantaneously liquefies the heat-irradiated portion of the solid coating to form a positive liquefied image, and transfers the positive liquefied image to a printing web passed between a transfer roll and an impression cylinder. A transfer printing method comprising printing, and then heating and liquefying the remaining solid coating adhered to the transfer roll, scraping the solid coating with a doctor, and collecting the solid coating on an ink tray.