JP2000122307A - Image transfer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image transfer device which facilitates the cooling and temperature management of a sheet-like member after discharging, is capable of rapidly advancing transfer work and is capable of producing a printed matter having high register accuracy. SOLUTION: This image forming device has (a) a pressing cylinder 10 for fixing an image forming material consisting of an image forming layer and a supporting sheet, (b) the sheet-like member 20 for fixing an image receptor, (c) a heating roller 30 arranged to face the pressing cylinder 10 and (d) an active energy ray source 40 which is arranged on the downstream side from the pressing cylinder and the heating roller and is used to cure the image forming layer transferred to the surface of the image receptor. The device described above transfers the portions of the image forming layer where the patterned latent images are formed, in the image forming material fixed to the pressing cylinder to the surface of the image receptor fixed to the sheet-like member by passing the sheet-like member fixed with the image receptor between the pressing cylinder and the heating roller. At this time, the rear surface of the sheet-like member discharge guide is provided with >=4 pieces of fans.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transfer apparatus capable of easily controlling the temperature of a sheet member and having excellent workability.

[0002]

2. Description of the Related Art Recently, an image-forming material having a photosensitive layer coated on one side of a support is image-exposed, and then the image formed on the photosensitive layer is heated, generally at about 100.degree. so,
Monochromatic or multicolor prepress proofs suitable for proof printing or the like transferred to an image receptor such as paper have been produced. The image forming material includes a support, a photosensitive layer formed on one surface of the support, and a protective film. As the support and the protective film, a thin film or sheet made of a material such as cellulose acetate, polystyrene, polyvinyl chloride, or polyethylene terephthalate is used. As the image receiver, a printing material selected as appropriate, such as paper or film, is employed.

As an apparatus for producing a prepress proof or the like, an image receptor is fixed between an impression cylinder on which an image forming material on which a pattern latent image to be transferred is formed and a heating roller arranged opposite to each other. An apparatus for transferring a portion of the image forming layer on which the pattern latent image is formed in the image forming material fixed to the impression cylinder by passing the formed sheet member to the surface of the image receptor fixed to the sheet member. Generally proposed. The sheet-like member generally uses a metal plate because it is necessary to transmit the necessary temperature to the image receptor at the time of transfer. The surface temperature of the latter half of the metal plate in the traveling direction immediately after discharge is close to 90 ° C. Next,
This removes the image forming material after transfer fixed to the impression cylinder, or fixes the image forming material to be transferred next. In the meantime, the metal plate is cooled at room temperature, but due to differences in work speed or room temperature, the surface temperature of the metal plate varies depending on the timing of removal from the discharge unit, and the first half and the second half in the transfer progress direction The temperature difference increases.

[0004] A metal plate has the property of being stretched by heat. If the expansion and contraction of the metal plate occurs at random during the production of the prepress proof, it also affects the image receptor and causes a decrease in the registration accuracy (alignment accuracy) of each color.

[0005]

SUMMARY OF THE INVENTION The present invention provides an image transfer apparatus capable of facilitating the transfer operation by cooling and controlling the temperature of a sheet-like member after discharge, and capable of producing a printed matter with high register accuracy.

[0006]

According to the present invention, an image receiving member is fixed between an impression cylinder on which an image forming material on which a pattern latent image to be transferred is formed and a heating roller arranged opposite to each other. Transferring the portion of the image forming layer on which the pattern latent image is formed in the image forming material fixed to the impression cylinder by passing the formed sheet member onto the surface of the image receptor fixed to the sheet member A guide for discharging the sheet-like member after the transfer, at least four or more fans installed on the back of the guide, and one or more surface temperature measuring devices near the upper and lower ends of the guide, respectively. The present invention provides a cooling device for a sheet-like member characterized by the following.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic sectional view of an image transfer apparatus used in the present invention, and FIG. 2 is a schematic sectional view of a sheet-shaped member discharge guide according to the present invention. Hereinafter, the configuration of the image transfer device used in the present invention will be described with reference to FIG. The image transfer apparatus includes an impression cylinder 10 for fixing an image forming material including an image forming layer on which a pattern latent image to be transferred is formed and a support sheet, and a sheet-like member 20 for fixing an image receptor. , A heating roller 30 arranged opposite to the impression cylinder 10, and an active energy ray source 40. The active energy ray source 40 is provided downstream of the impression cylinder 10 and the heating roller 30, and is provided for curing the image forming layer transferred to the surface of the image receptor. It consists of a low ultraviolet fluorescent lamp. The sheet member 20 is made of duralumin. A traveling direction changing unit 51 is provided near the impression cylinder 10 and the heating roller 30. The traveling direction changing means 51
The frame 53 includes a plurality of bearings 52 attached to the frame 53. The traveling direction changing means 51 comes into contact with the vicinity of the edge of the sheet member 20,
The traveling direction of the sheet-like member 20 that has passed between the impression cylinder 10 and the heating roller 30 is changed to the heating roller 30 side.

A blanket 11 made of rubber and having a thickness of 1.9 mm is wound around the circumferential surface of the impression cylinder 10. A notch 12 is provided on the circumferential surface of the impression cylinder 10. The notch 12 is provided with positioning means for fixing the image forming material to the impression cylinder 10, specifically, three pin bars 14. The blanket 11 is fixed in the notch 12 by blanket fixing means 13. An inclined portion 15 is provided between the notch 12 and the circumferential surface of the impression cylinder 10.
A and 15B are provided, and a pin bar 14 as positioning means is disposed on the inclined portion 15A. Pin bar 1
The pin bar 14 is provided with a blanket 11 having a hole at a position corresponding to the pin of the pin bar 14.
By pressing against the inclined portion 15A.
When the impression cylinder 10 rotates, the tip of the pin bar 14 does not protrude from the circumferential surface of the impression cylinder 10 so that the tip of the pin bar 14 and the sheet-like member 20 are not damaged. Reference numeral 16 denotes an ironing roller having a diameter of 50 mm, which is engageable with the blanket 11 and is used as a means for winding the image forming material around the upper circumferential surface of the impression cylinder. A sheet-shaped member insertion guide 50 is provided upstream of the impression cylinder 10 and the heating roller 30, and the sheet-shaped member 20 is placed and inserted into the sheet-shaped member insertion guide 50. A bearing (not shown) is attached to the sheet-like member insertion guide 50, and defines the traveling direction of the sheet-like member 20. On the other hand, a sheet member discharge guide 54 is provided downstream of the active energy ray source 40, and receives the sheet member 20 after the image forming layer transferred to the surface of the image receptor is cured. A bearing (not shown) is also attached to the sheet-shaped member discharge guide 54, and defines the traveling direction of the sheet-shaped member 20.

Hereinafter, a sheet-like member cooling apparatus according to the present invention will be described with reference to FIGS. 1, 2 and 3. FIG. The image receptor 60 is fixed to the surface of the sheet member 20 by the fixing member 61.
In the fixing member 61, a central layer (second layer) 63 is made of polyethylene terephthalate, and both layers (a first layer 62 and a third layer 64) are made of a three-layer plastic material of polyethylene. This is interposed between the image receiver 60 and the sheet-like member 20, and the pressed impression cylinder 10 and the heating roller 30
Then, the polyethylene formed on both sides of the fixing member 61 is melted by the heat from the heating roller 30 at about 110 ° C. to fix the image receptor 60 on the sheet member 20.

The image formed on the image forming layer 66 is rotated by rotating the image receiving member 60 fixed on the surface of the sheet-like member 20 and the image forming material fixed on the surface of the impression cylinder 10 in the arrow direction A. The image is transferred by being pressed against the image receiver 60.
The sheet member 20 after the transfer passes through the traveling direction changing means 51 and passes through the image forming layer 66 formed on the image receptor 60.
Is discharged to the sheet-shaped member discharge guide 54 while being cured by the irradiation of ultraviolet rays from the active energy ray source 40. The proximity switch 72 provided at the lower end of the sheet-shaped member discharge guide 54 detects the sheet-shaped member 20, and the fan 70 on the back of the discharge section starts to operate. At that time, the temperature measuring device 71 measures several points on the surface of the sheet-like member 20 at any time, and the measuring portion cools down to a temperature set in advance by a controller (not shown). When the temperature value falls within the allowable temperature difference, the fan 70 stops.
In general, the sheet member 20 is easy to cool in the first half and difficult to cool in the second half in the transfer progress direction. Therefore, the fan 70 is often provided above the sheet member discharge guide 54, but may be provided below. Sheet-shaped member discharge guide 54
Use a material in consideration of air permeability at the time of cooling, for example, a mesh plate having countless small-diameter holes. The temperature measuring device may be either a contact type or a non-contact type.

The above steps are performed four times (5 times including the fixing step of the image receptor 60), that is, yellow, magenta,
This is performed for four types of image forming materials corresponding to four colors of cyan and black. Hereinafter, the configuration of the sheet-shaped member cooling device of the embodiment will be described with reference to FIG. The sheet-like member 20 used a duralumin plate having a thickness of 0.5 mm. A total of four fans 70 were mounted on the upper rear surface of the sheet-shaped member discharge guide 54 so as to be equal in width to the duralumin, and one fan was provided at the center. The fan 70 has a maximum wind speed of 3.
0 (m ³ / min) (R87F manufactured by OMRON Corporation) was used.

The temperature measuring device 71 is an infrared radiation thermometer (manufactured by
Using a Keyence IT2-02), one sheet of the duralumin plate was attached to the center of the upper and lower ends of the sheet-shaped member discharge guide 54 so that the surface of the duralumin plate could be measured. The cooling condition is such that the fan 70 starts to operate at the same time as the proximity switch 72 detects the temperature, and the two upper and lower temperature measuring devices 71A, 71B
When the temperature values T1 and T2 indicate 30 ° C. and the difference between the temperature values falls within 5 ° C., the fan 70 is stopped. By using this cooling device, it took 4 minutes or more to cool the temperature at the T2 point of the duralumin plate to 30 ° C., but it was cooled in about 1 minute and the temperature distribution could be averaged. Was. In addition, since the expansion and contraction of the metal plate due to the temperature variation during the five transfer steps was reduced, the registration accuracy of the printed matter was also improved.

[0013]

According to the present invention, it is possible to rapidly cool a sheet-like member discharged after transfer in a high temperature state, and it is possible to produce a prepress proof in a shorter time as compared with a conventional image transfer apparatus. Become. In addition, since the variation in the surface temperature of the sheet-like member is reduced, the register accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a conventional image transfer apparatus, showing a state in which a sheet-like member is being moved.

FIG. 2 is a diagram illustrating a sheet-shaped member discharge guide, which is a part of the image transfer apparatus of the present invention.

FIG. 3 is a schematic partial cross-sectional view of a laminate of a sheet member, a fixing member, and an image receptor, and an image forming layer formed with a pattern latent image in an image forming material fixed to an impression cylinder. FIG. 9 is a schematic partial cross-sectional view showing a state where a portion is transferred to a surface of an image receptor fixed to a sheet member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Impression cylinder 11 Blanket 12 Notch 13 Blanket fixing means 14 Pin bar 15A, 15B Inclined part 16 Ironing roller 20 Sheet member 30 Heating roller 40 Active energy ray source 50 Sheet member insertion guide 51 Travel direction changing means 52 Bearing 53 Frame 54 sheet-shaped member ejection guide 60 image receptor 61 fixing member 66 image forming layer 70 fan 71A, 71B temperature measuring device 72 proximity switch

Claims (3)

[Claims] 1. An impression cylinder for fixing an image forming material comprising a support sheet and an image forming layer on which a pattern latent image to be transferred is formed, and a sheet for fixing an image receptor. (C) a heating roller arranged opposite to the impression cylinder; and (2) an image forming layer arranged downstream of the impression cylinder and the heating roller and transferred to the surface of the image receiving member. An active energy ray source for forming a latent image on the image forming material fixed to the impression cylinder by passing a sheet-like member on which the image receptor is fixed between the impression cylinder and the heating roller. The image forming layer portion transferred to the surface of an image receptor fixed to a sheet-like member, wherein at least four or more fans are provided on the back surface of the sheet-like member discharge guide. That Image transfer apparatus according to symptoms. 2. The apparatus according to claim 1, wherein at least two or more thermometers for measuring the surface temperature of both ends of the sheet-like member in the advancing direction of the sheet-like member are provided on the back surface of the sheet-like member discharge guide. Image transfer device. 3. The method according to claim 1, wherein the surface temperature of the sheet member discharged to the sheet member discharge guide is cooled to 20.degree. C. to 40.degree. The image transfer apparatus according to claim 2, wherein