JP3239572B2 - Image forming material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image forming material and an image forming method. More specifically, the present invention relates to an image forming material and an image forming method capable of obtaining a transferred material similar to a printed material as a prepress proof for color proofing.

[0002]

2. Description of the Related Art Conventionally, in order to predict the quality of a printed matter in advance of a large amount of printing, or to present a guarantee of quality,
2. Description of the Related Art A printing machine called a proofing machine prints several prints. However, printing with a proofing machine
It took time and time to be an expert in printing technology. Calibrators also take up space, are expensive, and require easier methods. In response to such demands, a method for easily forming an image for calibration without using a printing machine has been developed and used. In recent years, an image-forming material having a photosensitive layer provided on one side of a support is image-exposed, and then the image formed on the photosensitive layer is heated (typically around 100 ° C.) to an image receptor such as paper. A single-color or multi-color prepress proof suitable for proof printing or the like, which is transferred to a proof print, has come to be produced.

[0003] As a method for preparing the above prepress proof or the like, an impression cylinder having an image forming material attached thereto and a transfer cylinder having an image receptor attached thereto are arranged such that the photosensitive layer of the image forming material and the image receptor face each other. A technique has been proposed in which an image formed on a photosensitive layer in a nip between both cylinders is transferred to an image receptor by contact pressure and heating. To produce a multicolor print or prepress proof, a color original is color separated and image-exposed image forming materials of each color, eg, yellow, magenta, cyan, and black, are formed, and then these images are sequentially formed. The image formed on the photosensitive layer of the forming material will be transferred to the image receptor.

In the production of such a prepress proof, an uncured portion of an image forming material is softened by heating, and further pressurized to selectively transfer the uncured portion onto an image receptor. Have gained. However, when the surface of the image receptor is sufficiently smooth, good image transfer can be achieved. However, an image receptor having unevenness is also used. In the case of a body, transfer defects such as missing or blurred details of the image or jagged edges of the image are likely to occur, and it may be difficult to obtain a transferred image of good quality. Was.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a method for preparing a transfer image using an image-forming material, in which a non-smooth substrate (eg, mat-coated paper) having a rough surface is selected as an image receptor. Another object of the present invention is to provide an image forming material and an image forming method capable of obtaining a good image without transfer failure such as blurring.

[0006]

That is, the present invention provides a non-photosensitive layer which is softened at the temperature at the time of transfer but remains on the support at the time of transfer on the support. Form a photosensitive layer containing a colorant, further provided with a protective film on the photosensitive layer if necessary, image exposure, the adhesiveness in the transfer of the exposed part and the unexposed part in the photosensitive layer The difference provides an image forming material for transferring an image to an image receptor, wherein the non-photosensitive layer comprises a styrene-based thermoplastic elastomer. Further, the present invention provides a non-photosensitive layer containing a styrene-based thermoplastic elastomer on a support, which softens at the temperature at the time of transfer but remains on the support at the time of transfer, and provides a color on the non-photosensitive layer. Forming a photosensitive layer containing an agent, and further performing image exposure on an image forming material provided with a protective film on the photosensitive layer, if necessary, in the transfer of exposed portions and unexposed portions in the photosensitive layer. Provided is an image forming method characterized in that a photosensitive layer having high adhesiveness is selectively transferred to an image receptor due to a difference in adhesiveness.

As the support, cellulose acetate,
Thin films or sheets made of materials such as polystyrene, polyvinyl chloride, polyethylene terephthalate are used. The support is preferably made of a material through which actinic rays can pass. The thickness of the support is 3.0 to 25.0 μm, preferably 3.0 to 20.0 μm, and more preferably 10.0 to 15.0 μm. If the thickness of the support exceeds the above value, the flexibility of the support becomes insufficient, and the effect of filling the gap between the surface of the image receptor and the image forming material at the time of transfer becomes insufficient. When performing image exposure from above, the resolution is deteriorated due to light scattering by the support, and a good transfer image cannot be obtained.

[0008] The non-photosensitive layer contains a styrene-based thermoplastic elastomer. The non-photosensitive layer containing the styrene-based thermoplastic elastomer functions to closely follow the uneven surface of the image receptor and the gap during the transfer of the image forming material. Styrene-based thermoplastic elastomers are block copolymers having a polystyrene block structure at both ends and a polyolefin rubber block structure in the middle, and the polyolefin rubber in the middle consists of polybutadiene, polyisoprene, and polyethylene / butylene. At least one selected from them is preferably used. The middle polyolefin rubber part accounts for 50-80% of the copolymer. Specific examples include elastomers having a structure of styrene-polybutadiene-styrene, styrene-polyisoprene-styrene, styrene-polyethylene / butylene-styrene.

The non-photosensitive layer contains, in addition to the styrene-based thermoplastic elastomer, another resin that softens at the transfer temperature to adjust the thermal response, hardness, melt viscosity, etc. of the non-photosensitive layer. it can. As such a resin, a thermoplastic resin such as polyolefin, polyamide, polyurethane, polyester, acrylic resin, vinyl resin and a copolymer thereof can be used. The mixing ratio of the styrene-based thermoplastic elastomer to the other thermoplastic resin is preferably 95 to 5 parts by weight of the thermoplastic resin to 5 to 95 parts by weight of the styrene-based thermoplastic elastomer.

[0010] The other thermoplastic resin used for the non-photosensitive layer has a softening point of 70 to 150 ° C, preferably 90 to 120 ° C.
If a temperature within the range of 100 ° C. is selected, an appropriate melt viscosity will be obtained when transfer is performed at around 100 ° C., and good results can be obtained. For the non-photosensitive layer, it is preferable to select a material that does not dissolve in a diluting solvent when the photosensitive layer is applied. In addition, by containing a pigment in the non-photosensitive layer, appropriate adhesiveness, elasticity and coating suitability can be imparted. Also,
It is preferable to use a material that transmits active light rays used for image exposure for the non-photosensitive layer, because an image forming material capable of image exposure from the transparent support side can be prepared.

The thickness of the non-photosensitive layer is preferably 2.0 to 10.0 μm, more preferably 3.0 to 6.0 μm. If the thickness of the non-photosensitive layer is smaller than the above value, the effect of filling the gap between the surface of the paper and the image forming material cannot be sufficiently obtained when transferring to paper having a rough surface. On the other hand, if the thickness of the non-photosensitive layer is larger than the above value, a part of the non-photosensitive layer is transferred to the image receptor together with the image, which causes a problem in superimposition transfer in multicolor printing.

The photosensitive layer has such a property that a difference in tackiness between an exposed portion and an unexposed portion is caused by image exposure with actinic rays such as ultraviolet rays, so that a highly tacky region can be transferred to an image receptor. As a material whose adhesiveness is reduced by image exposure, there is a material in which a coloring agent such as a dye or a pigment and a polymerization initiator are added to a radically polymerizable compound having an ethylenically unsaturated bond. In this layer, a non-polymerizable resin having excellent compatibility with a compound having an ethylenically unsaturated bond may be appropriately compounded in order to adjust the adhesiveness. further,
A sensitizer, a thermal polymerization inhibitor and the like may be added. As the coloring agent, conventionally known coloring agents such as organic pigments, dyes and carbon black can be used, and the compounding amount is 5 to 50% by weight, preferably 9 to 20% by weight of the whole photosensitive layer. Several colorants can be mixed to obtain the required hue.

The compound having a radically polymerizable ethylenically unsaturated bond can be selected from monomers, oligomers and the like. These compounds include, for example, 2-
Hydroxyethyl (meth) acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, 1,6-hexanediol (meth) acrylate,
Trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate and the like can be mentioned. The photosensitive layer is provided on the non-photosensitive layer by dissolving, dispersing, and applying the above materials in an organic solvent. Photosensitive layer thickness 0.5 ~ 3.5μ
m, more preferably 1.2 to 2.3 μm. If the thickness of the photosensitive layer is too small, it is difficult to obtain a sufficient image density. If the value exceeds the above value, when the paper having a rough surface is used as an image receptor, the image edge portion may be disturbed during transfer. It is not preferable because it occurs.

As the protective film, cellulose acetate, polystyrene, polypropylene, polyethylene,
Materials such as polyvinyl chloride and polyethylene terephthalate and composite films thereof can be used. Rough paper that can be used as an image receptor is, for example, mat-coated paper (average surface roughness Ra = 1.3 μm, maximum surface roughness
Rmax = 14.0μm: Measured by Kosaka Laboratory surface roughness measuring instrument)
Etc. can be exemplified.

Hereinafter, the present invention will be described with reference to the accompanying drawings. The image forming materials of FIGS. 1, 3, 5, 7 and 8 are those after exposure to actinic rays, and have a difference in adhesiveness between irradiated and non-irradiated portions. When the photosensitive layer surface of the exposed image forming material is laminated with an image receptor such as paper and passed between heated rolls, the tacky photosensitive layer is selectively transferred to the image receptor. FIG. 1 is a schematic diagram showing a case where an image is transferred onto smooth paper 4 using a conventional image forming material 1, that is, a material in which a photosensitive layer 3 is directly provided on a support 2. 2 shows a cross section in which the paper 4 and the paper 4 are pressed against each other. Photosensitive layer 3
And the surface of the paper 4 are in close contact with each other, and as shown in FIG. 2, a good image free from blurring and edge disturbance can be obtained.

FIG. 3 is a schematic diagram showing a case where transfer is performed on a paper 5 having a rough surface by using the conventional image forming material 1.
The image forming material 1 adheres to relatively gently uneven portions on the surface of the paper 5, but the support 2 cannot follow the large uneven portions. Small gaps 6 and 7 occur between them. Therefore, FIG.
As shown in FIG. 7, an image lack 6 ′ and edge disorder 7 ′ occur. Reference numerals 6 and 6 'and 7 and 7' respectively indicate a state of a gap at the time of transfer and a state of a transfer failure corresponding thereto.

FIG. 5 shows the image forming material of the present invention, that is, a non-photosensitive layer 10 which is softened at the transfer temperature on a support 9 and a photosensitive layer 11 is provided thereon. FIG. 3 is a schematic diagram when an image is transferred to paper 5 having a rough surface. Uneven portions that could not be followed with conventional image forming materials,
Since the non-photosensitive layer 10 is softened by the heat applied at the time of transfer and is deformed in accordance with the unevenness of the surface of the paper 5, no gap is formed between the photosensitive layer 11 and the paper 5 as shown in FIG. A good transfer image is obtained.

FIGS. 7 and 8 are schematic views showing the state of the transfer of the photosensitive layer 11 during image transfer. The entire photosensitive layer 11 (FIG. 7) or a part (FIG. 8) in the thickness direction is transferred, and the non-photosensitive layer 10 is transferred to the paper 5 by being configured to remain on the support 9. It is possible to prevent a part of the non-photosensitive layer 10 from adhering to the surface of the image 12 to give an unnatural luster, or to prevent trouble in overprinting in multicolor printing.

[0019]

EXAMPLES The present invention will be described below with reference to examples. In the examples, parts mean parts by weight. Example 1 A non-photosensitive layer liquid having the following composition was prepared. Coating liquid for non-photosensitive layer Styrene-based thermoplastic elastomer 18 parts (Shell Chemical Co., Ltd. "Clayton G-1657") Thermoplastic resin (Arakawa Chemical Co., Ltd. "Alcon M-90") 2 parts Toluene 82 parts A colored photosensitive layer solution having the following composition was prepared. Diallyl isophthalate ("ISODAP" manufactured by Daiso) 21.23 parts Dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku) 7.08 parts Photopolymerization initiator benzophenone 0.5 part Diethylaminobenzophenone (manufactured by Hodogaya Chemical) 0 .17 parts Hydroquinone 0.001 part Carbon black ("MA-7" manufactured by Mitsubishi Kasei Kogyo Co., Ltd.) 5.0 parts Methyl ethyl ketone 78.0 parts

On a polyethylene terephthalate film (support) having a thickness of 12 μm, a non-photosensitive layer solution was applied by a bar coater and dried to form a non-photosensitive layer having a dry film thickness of 4.5 μm. Further, a colored photosensitive layer solution was applied on the non-photosensitive layer with a bar coater and dried to obtain a colored photosensitive layer having a dry film thickness of 1.3 μm. An image forming material was obtained by laminating a laminate of polypropylene and polyethylene terephthalate as a protective film on the colored photosensitive layer. A positive plate for plate making as an original was overlaid on the surface of the support of the image forming material, and image exposure was performed by ultraviolet light using a film printer (“P-647-GA” manufactured by Dainippon Screen).

Next, after applying this image forming material to the surface of the rubber roller so that the protective film surface is on the outside,
The protective film was peeled off. The surface temperature is 110 ℃
A mat coated paper ("Nulite" manufactured by Nippon Paper Industries Co., Ltd.) as an image receptor was attached to the surface of the heated metal roller. Next, when a nip pressure is applied so that the colored photosensitive layer of the image forming material and the image receptor are opposed to each other and the image is transferred, the details of the halftone dot image may be chipped, or the edge portion of the image may be jagged. A good image was obtained without any problem. The diameter of both rubber and metal rollers is 260
mm, nip pressure 7 kg / cm, and transfer speed 60 mm / min.

Example 2 A non-photosensitive layer solution having the following composition was prepared. Styrene-based thermoplastic elastomer 14 parts (Shell Chemical "Clayton G-1102") Thermoplastic (Arakawa Chemical "Alcon M-100") 5 parts Toluene 90 parts

Further, a colored photosensitive layer solution having the following composition was prepared by dispersing in a sand mill. Yellow Ink Pigment (Toyo Ink Mfg. Co., Ltd. "Lionol Ero-FG1310") 18 parts Diallyl phthalate (Daiso Co., Ltd. "DAPL") 30 parts Oligoester acrylate (Toa Gosei Co., Ltd. "M-7100") 14 parts Benzophenone 1 part Ethyl ketone 2.5 parts Methyl ethyl ketone 60 parts Methyl isobutyl ketone 60 parts

Magenta ink Pigment (“Rionol Red 7BFG4412” manufactured by Toyo Ink Mfg. Co., Ltd.) 16 parts Polyester resin (“Vylon 300” manufactured by Toyobo Co., Ltd.) 30 parts Tetraethylene glycol diacrylate 10 parts Trimethylolpropane triacryle -10 parts benzophenone 1 part 2-hydroxy-2-methylpropiophenone 3 parts methyl ethyl ketone 60 parts methyl isobutyl ketone 60 parts

Cyan Ink Pigment (Toyo Ink Mfg. Co., Ltd. “Lionol Blue-FG7330”) 16 parts Diallyl phthalate (Daiso Co., Ltd. “DAPL”) 30 parts Oligoester acrylate (Toa Gosei Co., Ltd. “M-7100”) ") 14 parts Benzophenone 1 part 4,4-bisdiethylaminobenzophenone 2.5 parts Methyl ethyl ketone 55 parts Methyl isobutyl ketone 55 parts

Black ink Pigment ("MA-7" manufactured by Mitsubishi Carbon) 8 parts Diallyl phthalate ("ISODAP" manufactured by Daiso) 22 parts Dipentaerythritol hexaacrylate 15 parts Benzophenone 1 part 4,4-bisdiethylamino Benzophenone 2.5 parts Methyl ethyl ketone 70 parts Methyl isobutyl ketone 55 parts

12 μm polyethylene terephthalate (P
ET) Apply the above non-photosensitive coating liquid to the film to a dry film thickness of 3.5
After coating to a thickness of 5.05.0 μm, each of the above color inks was coated to a dry film thickness of 1.3 to 2.2 μm and dried. Then 8μm polypropylene (OPP) and 50μm
The laminated film (protective film) of PET was laminated to produce an image forming material for each color (hereinafter referred to as an ink sheet). Using the obtained ink sheets of each color, an image was formed as follows. Holes were formed at one end of the black ink sheet with a punching machine. This hole was mounted on an exposure machine having a register pin, and a black positive film was patterned from a 12 μm PET film surface. The exposed ink sheet was mounted on a transfer machine having register pins, and the protective film was removed.
Print the ink surface on printing paper ("Mat-coated paper
Espel "), and the transferred pattern was exposed to ultraviolet light.

Next, in the same manner as the black ink sheet, the cyan positive film is patterned, the protective film of the cyan ink sheet is removed, and the ink surface is transferred to a printing paper on which a black pattern is formed. The resulting pattern was exposed to ultraviolet light. further,
After patterning the magenta positive film in the same manner as for the black ink sheet, remove the protective film from the magenta ink sheet, transfer the ink surface to printing paper on which the black and cyan patterns have been formed, and apply ultraviolet light to the transferred pattern. Was exposed. Finally, after patterning the yellow positive film in the same manner as the black ink sheet, the protective film of the yellow ink sheet was removed, and the ink surface was transferred to printing paper on which black, cyan, and magenta patterns were formed. After that, the transferred pattern is exposed to ultraviolet light,
An image having a texture very similar to that of a multi-color print of four colors was formed.

Example 3 An ink sheet of each color was produced in the same manner as in Example 2 except that the coating solution for the non-photosensitive layer was replaced with one having the following composition. Image was formed. Styrene thermoplastic elastomer 16 parts (Shell Chemical Co., Ltd. "Clayton G-1107") Thermoplastic resin (Zeon Corporation "Quinton C-185") 4 parts Toluene 90 parts [Example 4] Non-photosensitive layer coating Table 1 shows the dry film thicknesses of the non-photosensitive layer and the photosensitive layer.
The ink sheets of the respective colors were produced in the same manner as in Example 2 except that the ink sheets were replaced as shown in FIG. Styrene-based thermoplastic elastomer 16 parts (Shell Chemical Co., Ltd. "Clayton G-1650") Thermoplastic resin (Zeon Corporation "Quinton -200L") 4 parts Toluene 90 parts

Example 5 A coating solution for a non-photosensitive layer was changed to one having the following composition, and dry film thicknesses of the non-photosensitive layer and the photosensitive layer were changed as shown in Table 1. Each color ink sheet was manufactured in the same manner as in Example 2, and an image having a texture similar to that of the printed matter was formed. Styrene-based thermoplastic elastomer 16 parts ("Clayton G-1726" Shell Chemical Co., Ltd.) Thermoplastic resin ("Yasuresin TO-115" manufactured by Yasuhara Chemical Co., Ltd.) 4 parts Toluene 90 parts

Example 6 A coating solution for a non-photosensitive layer was changed to one having the following composition, and dry film thicknesses of the non-photosensitive layer and the photosensitive layer were changed as shown in Table 1. Each color ink sheet was manufactured in the same manner as in Example 2, and an image having a texture similar to that of the printed matter was formed. Styrene thermoplastic elastomer 4 parts (Shell Chemical "Clayton FG-1901X") Thermoplastic resin (Yasuhara Chemical "YS Polystar T-80") 16 parts Toluene 90 parts

Example 7 An ink sheet of each color was produced in the same manner as in Example 2 except that the coating solution for the non-photosensitive layer was changed to the one having the following composition. Image was formed. Styrene-based thermoplastic elastomer ("Tuftec H-1031" manufactured by Asahi Kasei Corporation) 14 parts Thermoplastic resin "Alcon M-100" 5 parts Toluene 85 parts Isopropyl alcohol 5 parts

Table 1 shows the results of observing the halftone dots, edge projections and dot shapes at the halftone dot area ratio of 5% of the images obtained in Examples 2 to 7 by a UGRA chart using a microscope.

[Table 1]

Comparative Example 1 An image forming material was manufactured and image transfer was performed in the same manner as in Example 1 except that the dry thickness of the colored photosensitive layer was changed to 1.8 μm except for the non-photosensitive layer. Was.
A satisfactory image could not be obtained, for example, a halftone dot image having a dot area ratio of 50% or less based on the UGRA chart was chipped, or a projection of several tens to hundreds of μm was formed at an edge portion.

Comparative Example 2 A non-photosensitive layer coating solution was applied to a dry film thickness of 4.0 μm instead of the following composition, and the dry thickness of the colored photosensitive layer was changed to 1.8 μm. An image forming material was manufactured in the same manner as in Example 1, and the image was transferred. However, the halftone dots were completely transferred, and image formation was not successful. Non-photosensitive layer coating liquid Thermoplastic resin “Alcon M-90” 20 parts Toluene 80 parts

[0036]

By using the image-forming material of the present invention, a good transferred image can be obtained without causing image chipping or the like even when a paper having a rough surface is used as an image receptor.

[0037]

[Brief description of the drawings]

FIG. 1 is a schematic diagram when an image is transferred to smooth paper using a conventional image forming material.

FIG. 2 is an image transferred to smooth paper by a conventional image forming material.

FIG. 3 is a schematic diagram when an image is transferred to a paper having a rough surface using a conventional image forming material.

FIG. 4 is an image transferred to paper having a rough surface by a conventional image forming material.

FIG. 5 is a schematic diagram when an image is transferred to paper having a rough surface using the image forming material of the present invention.

FIG. 6 is an image transferred to paper having a rough surface by the image forming material of the present invention.

FIG. 7 is a schematic diagram illustrating a state of transition of a colored layer by the image forming material of the present invention.

FIG. 8 is a schematic diagram illustrating a state of transition of a colored layer by the image forming material of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Conventional image forming material 2 Support
3 Colored photosensitive layer 4 Paper with a smooth surface 5 Paper with a rough surface 6,7 Gap created between the colored photosensitive layer and the paper 6 ′ Chipped image corresponding to the gap 6 6 Corresponds to the gap 7 ′ 7 Disturbance of image edge portion 8 Image forming material of the present invention 9 Support 1
0 Non-photosensitive layer 11 Colored photosensitive layer 12 Transfer image

Continuation of front page (56) References JP-A-3-174159 (JP, A) JP-A-2-123360 (JP, A) JP-A-2-58058 (JP, A) (58) Fields studied (Int .Cl. ⁷ , DB name) B44C 1/165-1/17 G03F 7/004 513

Claims (2)

(57) [Claims] (1) softening at a temperature at the time of transfer onto a support;
However , a non-photosensitive layer remaining on the support at the time of transfer is provided, a photosensitive layer containing a colorant is formed on the non-photosensitive layer, and a protective film is further formed on the photosensitive layer as necessary. In the image forming material for transferring an image to an image receptor, the non-photosensitive layer is a styrene-based thermoplastic elastomer due to the difference in adhesiveness between the exposed and unexposed portions of the photosensitive layer when the image is exposed to light. An image forming material comprising: 2. A styrenic thermoplastic elastomer on a support.
And softens at the transfer temperature, but
Is provided with a non-photosensitive layer remaining on the support, and on the non-photosensitive layer
Form a photosensitive layer containing a colorant, and if necessary
Forming material provided with a protective film on the photosensitive layer
To the exposed layer of the photosensitive layer,
Due to the difference in adhesiveness in the transfer of the optical part,
Characterized in that the light-sensitive layer is selectively transferred to an image receptor.
Image forming method.