JP2836307B2 - Image transfer device with tray - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transfer device. More specifically, the present invention relates to an image transfer apparatus including an image forming material attaching apparatus that can easily attach and detach an image forming material and does not cause misregistration caused by the image forming material.

[0002]

2. Description of the Related Art In recent years, 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 generally heated, for example, on paper or the like. A single-color or multi-color prepress proof suitable for proof printing or the like transferred to an image receptor has been produced.

[0003] When an image receptor such as paper is heated in advance, and a photosensitive layer of an image forming material is pressed against the image receptor to transfer an image formed on the photosensitive layer onto paper, the image is formed on one sheet of paper. 4
In the case of color printing, images of four colors are transferred in an overlapping manner. In this case, if wrinkles or the like occur when the image forming material is attached to the impression cylinder or the like, misregistration occurs in the overprinted second and subsequent colors, and a beautiful printed matter suitable for the purpose of proof printing cannot be obtained.

The image forming material used in the present invention comprises 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. Since the support and the protective film are made of such a soft material, they have a characteristic that wrinkles and the like are easily generated at the time of attachment to the impression cylinder.

As an apparatus for preparing the prepress proof, an impression cylinder having an image forming material attached thereto and a transfer cylinder having an image receptor attached thereto are arranged such that a photosensitive layer of the image forming material and the image receptor are opposed to each other. An apparatus has been generally proposed in which both cylinders are contact-pressed and an image formed on a photosensitive layer is transferred to an image receptor at a nip between the cylinders. In such an apparatus, as a device for attaching an image forming material in an impression cylinder, a soft sheet-like material such as a conventional image forming material can be easily attached and detached without wrinkles or the like.
Although there has been a strong demand for the development of a device for holding the register with excellent registration accuracy, a device satisfying such a demand has not yet been developed.

[0006]

SUMMARY OF THE INVENTION The present invention relates to an image transfer apparatus such as an apparatus for preparing a prepress proof, which is capable of transferring a soft sheet-like material such as an image forming material with excellent registration accuracy, and furthermore, mounting the sheet-like material. It is an object of the present invention to provide an image transfer device having an image forming material attaching device that can be easily removed.

[0007]

According to the present invention, there is provided an impression cylinder having an image forming material attached thereto and a transfer cylinder having an image receptor attached thereon, wherein the image formed on the photosensitive layer of the image forming material is subjected to the impression cylinder. Transferring the image to an image receptor by introducing the image to a nip between the image forming material and a transfer cylinder, wherein the transfer device holds the upper and lower sides of the image forming material on the surface of the impression cylinder over the entire width direction. A forming material adhering device, an image forming material charging tray, and an ironing roller for bringing the image forming material into close contact with the impression cylinder surface, wherein the upper side holding device has a partially cutout portion provided on the impression cylinder surface. And a magnet sheet for holding the image forming material between the sheet receiving portion and the impression cylinder surface near the notch, wherein the tray for charging the image forming material is Of the magnet on the impression cylinder surface It arranged to be positioned near the tip of the bets, ironing roller, providing the tray with the image transfer device which comprises installed to be brought into contact with the impression cylinder on the magnetic sheet on the impression cylinder surface.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view of an image transfer apparatus of the present invention including an impression cylinder 1 for applying an image forming material and a transfer cylinder 2 for applying an image receptor such as paper. FIG. 2 shows a partial perspective view of the impression cylinder 1. The impression cylinder 1 is partially provided with a notch 3, and a sheet receiving portion 4 is provided in the notch. The sheet receiving portion 4 is installed such that its tip does not protrude outside the circumferential surface of the impression cylinder. This is to prevent the transfer cylinder surface or the sheet receiving portion from being damaged due to the rotation of the impression cylinder 1 and the transfer cylinder 2. The sheet receiving portion 4 may be a pin bar 6 having at least one pin 5 in the axial direction of the impression cylinder 1 as shown in FIG. The pin bar 6 is preferable because the position of the image forming material on the impression cylinder can be easily set.

The tray 7 is rotatable about a fulcrum 8. When the image forming material is placed on the sheet receiving section 4, the tip of the tray 7 on the impression cylinder side is inclined toward the impression cylinder. After the upper side of the image forming material (not shown) placed on the tray 7 is placed at a predetermined position of the sheet receiving section 4, the image forming material is held by the magnet sheet 9. The magnet sheet 9 holds the image forming material between the sheet receiving portion 4 and the surface of the impression cylinder located near the partially cutout portion 3. The width shall not overlap with the trunk side tip. The sheet receiving portion 4 is formed of a material that attracts the magnet sheet 9, for example, iron, but the impression cylinder 1 does not necessarily need to be formed of a material that attracts the magnet sheet 9. By providing the magnet sheet 9 with appropriate hardness and flexibility, the image forming material may be held on the impression cylinder surface by the force received by the sheet receiving section 4. As shown in FIG. 2, the magnet sheet 9 has a partially cut-out portion 3.
A pin joint 10 is provided at the front in the rotation direction of the impression cylinder indicated by an arrow.
It may be installed so as to be rotatable via the.

After the image forming material is held by the magnet sheet 9, the ironing roller 11 is brought into contact with the magnet sheet on the magnet sheet 9 on the surface of the impression cylinder. At this time, the ironing roller 11 does not contact the tray 7, but is preferably in the vicinity of the tray 7. If an unnecessary distance is provided between the ironing roller 11 and the tray 7,
The image forming material is likely to be lifted between the magnet sheet 9 and the tray 7 and is likely to cause misalignment due to wrinkles or the like. The ironing roller 11 is installed at a position away from the impression cylinder when the ironing roller is not used by means (not shown) such as a roller provided on a shaft portion of the roller and a guide rail provided on a frame of the transfer device. It is preferable to keep it in order to facilitate the transfer operation. The contact pressure between the ironing roller 11 and the magnet sheet 9 is appropriately adjusted by its own weight or by an elastic member such as a spring so as to prevent wrinkles or the like of the image forming material based on the magnitude of the pressure.

The pressure-sensitive adhesive tape 12, preferably a double-sided pressure-sensitive adhesive tape, is preferably installed on the surface of the impression cylinder below the tray 7 and near the tip of the tray along the axial direction of the impression cylinder. Further, in order to avoid damage to the attachment means such as a clamp 13 for attaching an image receptor (not shown) provided on the surface of the transfer cylinder 2 or the surface of the impression cylinder due to the contact between the impression cylinder 1 and the transfer cylinder 2. It is preferable to provide another cutout portion 14 which is recessed inward from the circumferential surface of the impression cylinder at the front of the partially cutout portion 3 of the impression cylinder 1 in the direction of the arrow.

The ironing roller 11 is moved to the magnet sheet 9
After contacting the upper side, the impression cylinder 1 is rotated in the direction of the arrow shown on the impression cylinder. The image forming material passes over the adhesive tape 12 while being in close contact with the surface of the impression cylinder by the ironing roller 11, and is fixed by the adhesive tape. Further, the rotation of the impression cylinder 1 is continued, and an image forming material attaching means such as an adhesive tape 12 provided with the lower side of the image forming material on the surface of the impression cylinder or a clamp (not shown) provided in another notch 14 is provided. Hold by.

The operation of the image transfer apparatus of the present invention will be described below. The tray 7 is rotated about the fulcrum 8 to tilt the tip end of the tray 7 on the impression cylinder side toward the impression cylinder side. The upper side of the image forming material placed on the tray 7 is placed at a predetermined position of the sheet receiving section 4. Next, the magnet sheet 9 is placed near the tray 7 so that the sheet receiving portion 4 and the magnet sheet do not overlap with the tray 7.
As shown in FIG. 2, when the pin bar 6 is used as the sheet receiving portion, a pin hole is opened in a position corresponding to the pin 5 of the pin bar in advance, and the image forming material is set.
Next, the magnet sheet 9 is rotated to fit the pin holes 15 of the sheet into the pins 5 of the pin bar. By holding the image forming material by the magnet sheet, the image forming material is pressure-bonded to the sheet receiving portion 4 or the pin bar 6 on the surface. Therefore, the tensile force applied when the image forming material is wound around the impression cylinder 1 is applied to the entire width of the image forming material, and partial elongation of the image forming material, particularly, partial elongation in the vicinity of the pin hole is prevented. There is no misalignment and the image forming material can be installed with high registration accuracy. The use of pin bar 6
This is preferable because the image forming material can be easily set at a predetermined position.

Next, the ironing roller 11 is brought into contact with the magnet sheet 9 on the surface of the impression cylinder. When the ironing roller is in direct contact with the image forming material instead of the magnet sheet, it causes wrinkles due to the lifting of the image forming material and the like, and it is impossible to obtain a beautiful printed matter having excellent registration accuracy.

The ironing roller 11 is moved to the magnet sheet 9
After that, the impression cylinder 1 is rotated in the direction of the arrow. When the adhesive tape 12 is provided, the image forming material is pressed on the adhesive tape 12. Since the image forming material is made of a soft material, the image forming material may be lifted even near the leading end of the magnet sheet. By fixing this with the adhesive tape 12, the image forming material is evenly adhered to the surface of the impression cylinder over the entire width, so that there is no deviation in registration accuracy due to partial lifting or the like. In order to effectively prevent the tray 7 from coming into contact with the image forming material, it is preferable to provide rolling means such as rollers on both sides of the tip.

Further, the impression cylinder 1 is rotated in the direction of the arrow, and the lower side of the image forming material is pressed against an adhesive tape provided in the vicinity of the other cutout portion 14 of the impression cylinder 1 in the direction of the arrow. Alternatively, the image forming material is held by a clamp (not shown) provided in another cutout portion 14. The image forming material comprises a support, a photosensitive layer and a protective film. Generally, the material on which an image is formed by image exposure is attached to the impression cylinder 1 by the above-mentioned operation with the protective film attached. Next, the magnet sheet 9 is removed, the protective film is removed, and then the magnet sheet 9 is placed again so that the image forming material without the protective film is pressed against the sheet receiving portion 4 or the pin bar 6.

In a multi-color, for example, four-color, prepress proof, the four-color image forming material is transferred to one image receptor, for example, paper, so that the image forming material can be easily attached and detached, and the registration accuracy is high. The device attached to the impression cylinder
Very importantly, the image transfer device of the present invention meets this need.

[0018]

According to the present invention, there is provided an image transfer apparatus which can easily attach and detach an image forming material and can be attached to an impression cylinder with high registration accuracy.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an image transfer device.

FIG. 2 is a partially enlarged view of an image attaching device for an impression cylinder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Impression cylinder 2 Transfer cylinder 3 Partially notched part 4 Sheet receiving part 6 Pin bar 7 Tray 9 Magnet sheet 11 Ironing roller

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03F 7/26-7/42 G03F 3/10

Claims (4)

(57) [Claims] 1. A nip between an impression cylinder and a transfer cylinder, comprising an impression cylinder having an image forming material attached thereto and a transfer cylinder having an image receptor attached thereto. An image forming material adhering device for holding the upper side and the lower side of the image forming material on the surface of the impression cylinder over the entire width direction; and an image forming apparatus. A material loading tray, and an ironing roller for bringing the image forming material into close contact with the impression cylinder surface, wherein the upper side holding device includes a sheet receiving portion installed in a partially cutout portion provided on the impression cylinder surface; A magnet sheet for holding the image forming material between the sheet receiving portion and the impression cylinder surface near the cutout portion. Part on the impression cylinder surface An image transfer device with a tray, wherein the image transfer device is provided so as to be located near a tip end of the tray, and an ironing roller is installed so as to contact the impression cylinder on a magnet sheet on the surface of the impression cylinder. 2. The image transfer device according to claim 1, wherein
The upper side holding device further comprises an adhesive tape provided along the axial direction on the surface of the impression cylinder near the leading end of the magnet sheet, and the leading end of the tray for loading the image forming material has the adhesive tape and the magnet sheet. And an image transfer device with a tray. 3. The image transfer apparatus according to claim 1, wherein
An image transfer device with a tray, wherein the sheet receiving portion is a pin bar having at least one pin in the axial direction of the impression cylinder, and the magnet sheet is provided with a pin hole at a position corresponding to the pin. 4. The image transfer apparatus according to claim 1, wherein
An image transfer device with a tray, wherein the image forming material loading tray is provided with rolling means for rolling the surface of the impression cylinder on both sides of the tip of the tray.