JP2000122308A - Image transfer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image transfer device which has excellent repetitive stability and workability by eliminating a phenomenon that an image forming material is removed from a pressing cylinder. SOLUTION: This image transfer device has a pressing cylinder 10 for fixing an image forming material 5 consisting of an image forming layer 60 where the patterned latent images to be transferred are formed and a supporting sheet, the sheet-like member 20 for fixing an image receptor, a heating roller 30 arranged to face the impression cylinder and an active energy ray source 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 potions 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 to the image receptor between the pressing cylinder and the heating roller. At this time, the sheet-like member is partly lipophobic and the coefficient of dynamic friction of the portion is <=2.0.

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 excellent in workability in which an image forming material is not removed from an impression cylinder when an impression cylinder and a sheet-like member are pressed.

[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. A blanket is wrapped around the surface of the impression cylinder. The blanket is provided to maintain the elasticity in the nip in a proper range when the image forming material and the image receptor are transferred by pressure. An adhesive tape is used as a means for fixing the image receptor on the surface of the impression cylinder.
Conventionally, an adhesive tape is provided to hold the upper side and the lower side of the image forming material on the blanket surface over the entire area in the width direction. The sticking position is the upper side and the lower side of the transferable area of the blanket surface and the position where the heating roller is pressed at the start of the transfer. The reason why the image forming material is stuck at the press-bonding position is that the image forming material adheres to the sheet-like member due to the adhesive force of the image forming layer due to the pressure and heat generated during the press bonding, and the image forming material is removed from the impression cylinder. This is because Moreover, among the various image forming materials, those having a strong adhesive force of the image forming layer may be detached from the impression cylinder even though they are fixed with the adhesive tape. In addition, the adhesive force generated when pressure is applied prevents the sheet-shaped member from advancing, resulting in a decrease in registration accuracy (positioning accuracy). Further, since the adhesive tape on the surface gradually decreases due to the attachment and detachment of the image forming material several times because the adhesive tape is gradually replaced with a new one, it is preferable that the number of sticky tapes is as small as possible.

[0004]

SUMMARY OF THE INVENTION The present invention provides an image transfer apparatus which eliminates the conventional phenomenon that occurs at the start of transfer and in which the image forming material is removed from the impression cylinder, and which is excellent in repetition stability and workability. I do.

[0005]

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 , Part of the tip of the sheet-shaped member is oleophobic (property that repels oily material)
And a dynamic friction coefficient of the portion is 2.0 or less.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view of an image transfer apparatus used in the present invention, and FIG. 2 is a schematic enlarged view of a portion where an impression cylinder and a heating roller according to the present invention start to be pressed. FIG. 1 shows the configuration of an image transfer device used in the present invention.
This will be described below. The image transfer device includes an image forming layer 66 on which a pattern latent image to be transferred is formed and a support sheet 65.
Impression cylinder 10 for fixing image forming material 5 comprising
And a sheet-like member 20 for fixing the image receptor 60
A heating roller 30 disposed opposite to the impression cylinder 10;
An active energy ray source 40 is provided. 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 66 transferred to the surface of the image receptor 60. It is composed of a plurality of low ultraviolet fluorescent lamps. The sheet member 20 is made of duralumin in the embodiment. 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 5 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 1 is provided between the notch portion 12 and the circumferential surface of the impression cylinder 10.
5A and 15B are provided, and a pin bar 14 as positioning means is provided on the inclined portion 15A. The pin bar 14 is disposed by pressing the pin bar 14 with the blanket 11 having a hole at a position corresponding to the pin of the pin bar 14.
It can be performed by pressing against the 0 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 freely engageable with the blanket 11 and is used as a means for winding the image forming material 5 around the upper circumferential surface of the impression cylinder 10.
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 is attached to the sheet-like member insertion guide 50 to define the traveling direction of the sheet-like member 20. On the other hand, a sheet-like member discharge guide 54 is provided downstream of the active energy ray source 40, and the sheet-like member 2 after the image forming layer transferred to the surface of the image receptor 7 is cured.
Receives 0. A bearing is also attached to the sheet-shaped member discharge guide 54, and defines the traveling direction of the sheet-shaped member 20.

Hereinafter, the present invention will be described with reference to FIGS. 1, 2 and 3. The fixing member 6 is attached to the surface of the sheet-like member 20.
1 fixes the image receptor 60. This fixing member 6
In 1, 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 receiving member 60 and the sheet-like member 20, and is passed between the pressure-pressed impression cylinder 10 and the heating roller 30.
The image receiving member 60 is fixed on the sheet-like member 20 by being melted by the heat from the heating roller 30 at ℃.

The image receiving member 60 fixed on the surface of the sheet member 20 and the image forming material 5 fixed on the surface of the impression cylinder 10 are formed on the image forming layer 66 by rotating in the direction of arrow A. The image is pressed onto the image receiver 60 to transfer the image. At that time, an adhesive force is generated between the sheet-shaped member 20 and the image forming material 5 at the start of the pressure bonding. In order to prevent the image forming material 5 from sticking to the surface of the sheet member 20 with this adhesive force,
An oleophobic treatment section 9 is formed on the surface of the sheet-shaped member from the front end of the sheet-shaped member, specifically, a distance M from the front end to the lower side adhesive tape 3. The term "oleophobic" as used herein means that the ink used for the image forming material 5 hardly arrives on the surface of the oleophobic treated portion, and preferably does not arrive at all. As the oleophobic material, silicone resin,
Fluoro resin is exemplified, but not limited thereto. As a forming method, various coating methods may be directly applied to the surface of the sheet-like member, or an oleophobic resin may be formed on the surface of the pressure-sensitive adhesive tape substrate, and the resin may be attached to the surface of the sheet-like member 20. Other necessary characteristics of the oleophobic material used in the oleophobic treatment section 9 are that it is heat-resistant at high temperatures up to about 160 ° C. and has a low coefficient of friction.

The coefficient of kinetic friction on the surface of the oleophobic treatment section 9 of the present invention was measured by the following measuring method. A blanket 11 in which a support sheet 65 having a cured image forming layer 66 of 63.5 mm square was applied to the plane indenter of the measuring device using a HEIDON 14 type surface property measuring device (manufactured by Shinto Chemical). To the sample stand of the measuring machine.
A test piece molded of silicone resin or fluorine resin is attached to the front of the sample table. A vertical load of 200 gf is applied to the entire flat indenter, and the sample table is set at 600 mm /
By moving at a speed of min, the dynamic frictional resistance generated at this time is measured, and the dynamic friction coefficient is calculated.

Hereinafter, the present invention will be described in more detail based on embodiments. For the oleophobic treatment section 9, four types of pressure-sensitive adhesive tapes having a base made of a heat-resistant pressure-sensitive adhesive tape whose surface is formed of a silicone resin and a fluorine resin were used. Sample 1: A polyethylene film having a thickness of 20 μm was laminated on the surface of a base material, and a silicone film having a thickness of 1 μm was formed on the surface.
Resin (Toray Dow Corning Silicone Co., Ltd. S
RX357) Sample 2: Fluoro resin adhesive tape (Chukko Kasei Kogyo Co., Ltd.)
Sample 3: Adhesive tape of fluoro resin (Nitoflon 903UL, thickness 0.13 mm, manufactured by Nitto Denko Corporation)
Sample 4: Adhesive tape of fluoro resin (Chukko Kasei Kogyo Co., Ltd.)
(Trade name: AGF100, thickness 0.13 mm).

[0012] These adhesive tapes are applied to the sheet-like member 20.
In parallel with the width direction at a distance M at the tip. In this embodiment, the distance M was 35 mm. Next, the image forming material 5 having a pattern latent image formed thereon is fixed on the surface of a blanket (“FD650 (trade name)” manufactured by Fujikura Rubber Industries, Ltd.), and a sheet-like member is placed between the impression cylinder 10 and the heating roller 30. The heating roller 30 is applied to the impression cylinder 10 with a linear pressure of about 7
After pressing at kg / cm, transfer to the sheet-like member 20 was started at a moving speed of 5 to 10 mm / sec, and the effect was confirmed. At this time, the surface temperature of the heating roller 30 is 150 ± 3.
Set to ° C. The above steps are performed through the curing treatment of the image forming layer 66 by the post-transfer active energy ray source 40.
Times, i.e. 4 for yellow, magenta, cyan and black
The effect of the present invention was confirmed by transferring four colors corresponding to the colors. As for the oleophobic effect, the sheet-like member 2
The solid image was directly transferred to the surface of No. 0, and the evaluation was made with the ink applied. Table 1 shows the evaluation results.

[0013]

[Table 1]

[0014]

According to the present invention, the phenomenon that the image forming material is detached from the impression cylinder, which occurs when the impression cylinder and the sheet-like member are pressed against each other, can be eliminated, and the adhesive tape for fixing the image forming material to the blanket surface can be eliminated. Can be reduced.

[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 part of the image transfer method of the present invention and is an enlarged view of a pressure bonding start portion during transfer.

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]

 REFERENCE SIGNS LIST 3 adhesive tape 5 image forming material 9 oleophobic treatment section 10 impression cylinder 11 blanket 12 cutout section 13 blanket fixing means 14 pin bar 15A, 15B inclined section 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 discharge guide 60 Image receptor 61 Fixing member 66 Image forming layer

Claims (1)

[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. Forming a latent image on the image forming material fixed to the impression cylinder by passing a sheet-like member having the image receptor fixed between the impression cylinder and the heating roller. An image transfer device, wherein a portion of the image forming layer is transferred to a surface of an image receptor fixed to the sheet-shaped member, wherein a part of the sheet-shaped member is oleophobic, and a kinetic friction of the portion is provided. Coefficient is 2.0 or less Image transfer apparatus according to claim and.