JP2887312B2 - Image forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of the Invention] (Industrial application field) The present invention relates to image formation, and more specifically, the difference in adhesiveness between an exposed portion and an unexposed portion of a photosensitive layer. The present invention relates to an image forming method using a single color or a multi-color superimposition using a method for obtaining a transferred material similar to a printed material as a prepress proof for color proofing.

2. Description of the Related Art Conventionally, in the printing industry, it is known to use a prepress proof as a means for confirming the finish, color tone, and the like of a finally printed product before printing. This prepress proof includes an overlay method and a surprint method, which are used depending on the image quality to be finally obtained and the intended use in plate making and printing processes.

In the overlay method, each transparent base film is provided with a photosensitive layer corresponding to each color separation (color separation) image, and each film obtained by the actinic ray irradiation and development process is visually checked for color separation registration. Overlap. Although this method is very simple, it has a drawback that it is greatly affected by the reflected light from the film at the time of superposition and differs from the actual texture of the printed matter.

The surprint method is described, for example, in US Pat.
As disclosed in JP-A-3060024 and JP-A-3060025, several photosensitive layers are superimposed on a single support to sequentially form color-separated images. As the coloring, there are a method of simple transfer and a method of powder color toner, but the method of transfer has an advantage that the operation is simple. On the other hand, the method using powder color toner requires work environment considerations because of the powder. The purpose of the prepress proof is to request a copy similar to a printed matter, but it is hard to say that the glossiness and the halftone dot reproducibility are close to the printed matter by the transfer method conventionally proposed. Also,
In the method using powder color toner, it is difficult to approximate the actual printed matter because the work is far from printing.

Further, the transfer method disclosed in U.S. Pat. No. 3060023 discloses a work in which a photosensitive layer and an image receptor are heated in close contact with each other under pressure and then peeled off. However, there is a problem that it lacks stable image reproduction and quickness required for prepress proof. In the peeling after pressure contact, the peeling speed,
There is a disadvantage in work that adjustment of direction and strength is difficult.
In other words, when the photosensitive layer and the image receptor are peeled after being pressed and adhered in a plane, unless the working conditions are strictly adjusted,
It is easy to cause paper waste. In addition, even under conditions that do not cause paper scuffing, it is difficult to maintain constant work conditions such as the speed and direction of peeling, and the reproduction of the transferred image becomes unstable.
A nonuniform reflection density of the transferred image, a fine periodic pattern, and a fine directional pattern are generated, and the accuracy of color reproduction and the like is significantly reduced.

Japanese Patent Publication No. 42-14326 discloses a sheet comprising a support and a sheet coated with an ultraviolet-sensitive layer and a diazo photosensitive material, which is transferred to a single support by using pressure, and then transferred through a halftone negative. Image exposure is performed, followed by a development step, which can be sequentially repeated on the same support. This method also sequentially forms color-separated images on the same support. However, since a development step using a solvent is involved, not only is there a problem with the working environment, but also the resulting image is fragile. Has disadvantages.

Japanese Unexamined Patent Publications Nos. 59-97140 and 61-188537 disclose proofing systems that can be used for both the overlay method and the surprint method. In this proofing system, (1) a color sheet in which a release layer, a colored photosensitive layer, and a protective layer are sequentially laminated on a polyester support, and an image receiving film including an image receiving layer and a protective film on the polyester support are prepared. (2) The emulsion surface of the color sheet is brought into close contact with the halftone negative to form an image, and the unexposed portion is eluted with a mixed solution of sodium carbonate, butyl cellosolve, and water. After drying, it is also effective as an overlay type proofing.

(3) Proofing as a surprint method is performed by sequentially performing registration by visual or punching on an image receiving film under the conditions of temperature 110 ° C., pressure 2 bar, speed 60 cm / min in the order of black, cyan, magenta, and yellow. (4) After obtaining a normal image by transferring the image to a receptor as a transfer object, in order to reduce the reflection gloss of the transfer layer and the colored layer, transfer the film subjected to matting to obtain proofing. .

This method is characterized in that a release layer is provided between the photosensitive coloring layer and the support, and this layer has no adverse effect on the transfer image quality under high temperature and high humidity conditions, and therefore, is closer to a printed matter. Although it can give a texture, it requires a matting process and is not always very close to a printed matter.

Further, for example, in Japanese Patent Application Laid-Open No. 59-97140, since the direction of an image is opposite to that of a printed matter in one transfer, a transfer step is required again. Regarding the orientation of the image obtained by one transfer, the image is reversed, so it is necessary to transfer again or a normal image can be obtained by one process, but the accuracy of the image decreases, that is, the sharp image becomes There was a disadvantage that it could not be obtained. In normal image formation using a proofing sheet, for example, an original layer of a polyethylene terephthalate film having an original image layer formed on one side is used as a cover sheet for a proofing sheet composed of a cover sheet (polyethylene film) / photosensitive layer / support. The layers are laminated so as to be in contact with each other and exposed. After the exposure, the cover sheet is peeled off, and the image is formed by pressing the cover sheet against the image receptor. Therefore, the image formed on the photosensitive layer is a reverse image, and if a normal image is obtained, a re-transfer process is required. In this case, since only the cover sheet is present between the original image layer and the photosensitive layer, the thickness is not so large, and light diffusion (reducing image accuracy) due to exposure is relatively small. Since the surface shape of the polyethylene film as the cover sheet is rough, it is difficult to form an image with high accuracy.

If a normal image is to be obtained by a single process, upon exposure, a polyethylene terephthalate film having an original image layer formed on one side is laminated so that the film surface is in contact with a cover sheet, and is exposed. In this case, peeling off the cover sheet
Although a normal image can be obtained, the thickness of the cover sheet and the polyethylene terephthalate film between the original image layer and the photosensitive layer is so large that light diffusion due to exposure (reducing image accuracy) occurs. The image quality is reduced.

As described above, various proofing methods have been studied. Regarding the transfer method, a method using a plane transfer or a letterpress proof printing machine is known. As described above, the method of transferring in a planar manner has various disadvantages. In the transfer by the proof printing machine, the exposed image forming material is fixed to a blanket cylinder, the blanket cylinder is rolled, and the image is transferred to an image receptor held on a paper platen. This method using a proof printing press is generally not only disadvantageous in terms of space and cost because the apparatus is large and heavy, but also it is difficult to stabilize the heating required for transfer and the temperature after heating, and it is difficult to obtain uniform image formation. ， Work preparation often takes time. Further, in the method using a proof printing machine, exposure is performed by another apparatus, and it is difficult to continuously perform exposure and transfer.

(Problems to be Solved by the Invention) Regardless of the method by which a prepress proof can be prepared, the method involves a substantial development step, and the preparation step is complicated. So far, it has been mainly used for checking processes between plate making and printing, but it has been recognized that the quality is different even if it is used as a substitute for actual printed matter.

For this reason, there has been a demand for a method capable of forming a fine image with a constant reflection density of the formed image.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming method capable of forming an image having the same image quality as that of the printed matter of this machine. That is, the method is excellent in color reproduction, in which reproduction of an image to be transferred is stable, and non-uniformity of reflection density of the transferred image, periodic pattern, and pattern with fine directionality are not generated.

An object of the present invention is to provide a method capable of performing uniform transfer without causing paper waste during transfer.

The present invention is advantageous in terms of space and cost as compared with a proof printing press, requires less time for work preparation, can stably perform uniform image formation, and continuously performs from exposure to transfer. It also provides a possible method.

Further, the object of the present invention is to take into account such conventional disadvantages,
The purpose of the present invention is to provide a simple image forming material that can be used effectively in a surprint method and that the final image obtained by the surprint method has the same orientation as a printed image. Is a method that can be provided.

SUMMARY OF THE INVENTION The present invention provides a method capable of obtaining an image equivalent to a proof print by a proof printer and eliminating proof by the proof printer.

As a result of the study, the present inventors have found that a photosensitive layer formed between a support and a cover sheet can be formed into a monochromatic or multicolor image by selecting a material and / or a method having an appropriate cohesive force inside the photosensitive layer. In the image exposure for the purpose of producing the image, an unexposed portion has an appropriate adhesive force, and an image is obtained by cohesive failure in a nip between rollers.
For this reason, it has been found that a specially processed image receptor or an intermediate image receptor is unnecessary and simpler than the prior art, and the present invention has been reached.

[Configuration of the invention]

(Means for Solving the Problems) The present invention provides a support, which is a film or sheet made of at least one selected from the group consisting of cellulose acetate, polystyrene, polyvinyl chloride, polyethylene terephthalate, polycarbonate, polyimide, and polypropylene that transmits actinic rays. Dyes and / or pigments on top,
An image-forming material formed by forming a photosensitive layer containing a photopolymerizable compound and a diallyl phthalate resin as a thermoplastic resin is image-exposed, and the difference in tackiness in transfer between an exposed portion and an unexposed portion of the photosensitive layer. An image forming method for transferring an image based on cohesive failure in which an image formed by image exposure to a paper or other image receptor is not transferred at least in all thicknesses, comprising an exposed image forming material and an image receptor Respectively so that the photosensitive layer of the forming material and the image receptor face each other, and the surface temperature of one roller is
The present invention provides an image forming method characterized in that it is guided between rollers having a temperature of 50 to 150 ° C. and a roller diameter of 30 to 500 mm, transferred at a nip between the rollers, and peeled immediately after passing through the nip.

The present invention is a method for obtaining a color proof that can be easily, quickly and stably prepared with the same texture as that of an actual printed matter in a surprint method. Of course, this method is also applicable to the overlay method. That is,
The present invention is a dry developing method which can obtain a printed matter having almost the same texture as that of the printed matter of the present invention and does not require a developing solution, that is, a method capable of obtaining a color proof having stable quality by development by peeling.

According to the image forming method of the present invention, there is no swimming (fine periodic pattern or fine directional pattern) in the image forming material due to heating at the time of transfer, and the image forming material is directly applied to an art paper or the like, which is an ink receiver for printing on the machine. The copy can be transferred, and further, the photosensitive layer is transferred in the same state as the printing of this machine, so that a copy very similar to the actual print can be obtained. In addition, this method can stably transfer a fine image.

The image forming material according to the present invention usually has a structure of a support / colored photosensitive layer / protective film, which will be described below.

As a support, it is stable to heat, chemicals, light, etc.
In addition, a material that transmits active light is preferable. Examples thereof include films or sheets of cellulose acetate, polystyrene, polyvinyl chloride, polyethylene terephthalate, polycarbonate, polyimide, polypropylene, and the like. In particular, a polyethylene terephthalate film or sheet is preferred in terms of transparency, thermal stability, dimensional stability and the like.

Further, these supports may be used as they are, or may be subjected to a release treatment with a suitable oil-repellent substance. Examples of these oil-repellent substances include silicone resins and fluororesins.

Examples of the protective film include, but are not limited to, polyethylene film, polyethylene terephthalate film, and acetate film.

The photosensitive layer according to the present invention has a constitution of a photopolymerizable compound, a diallyl phthalate resin as a thermoplastic resin and a colorant, and usually further contains a photopolymerization initiator and a thermal polymerization inhibitor.

As the photopolymerizable compound, at least one selected from monomers, oligomers and prepolymers is used.

 Further, other additives can be used in combination.

The photopolymerizable compound is not particularly limited, but is preferably a compound capable of plasticizing a thermoplastic resin at room temperature.

For the photosensitive layer, a photopolymerizable compound is used so as to be mixed with a dye and / or a pigment and can be cured by exposure.

The photosensitive layer is formed on a support, and a protective film (cover sheet) is further provided on the photosensitive layer. The cover sheet is used to prevent contamination due to the adhesion of the photosensitive layer to an exposure device or the like when performing exposure for image formation from the support side, and a polyethylene film is preferable. It is not limited to this.

Since the photosensitive layer is photopolymerizable, the cured portion loses its adhesive strength to the image receiving layer by image exposure, and enables the creation of fine image reproduction by the moderate internal gathering power of the unexposed portion, and It has the advantage of facilitating transfer onto the image receptor by peeling. Here, having moderate internal gathering power means that the image formed on the image receptor is not transferred at least in all thicknesses.

The appropriate internal cohesion of the photosensitive layer according to the present invention can be variously selected depending on the type and / or the mixing ratio of the photopolymerizable compound, dye or pigment used in the photosensitive layer. Further, it varies depending on the type of the image receiving layer or the support.

In the color proofing work of a printed material to which the present invention is applied, it is necessary to reproduce an image with high accuracy from a film or the like serving as an original. Similarly, it is necessary to shorten the time for the color proofing work. In order to satisfy these demands and to ensure a stable finish quality, thinning of the film thickness of a formed image is a main technical factor for accurate image reproduction. Further, a major technical factor in terms of time reduction is that the formed image does not require a developing operation or the like. In order to realize these requirements and technical elements, the film of the formed image is given an appropriate internal suspicion force, so that the delamination in the photosensitive layer is caused.
Omitting the development step is the best solution.

As the photopolymerizable compound that can be used in the present invention, an ethylenically unsaturated compound is preferable. For example, (meth) acrylic acid, methyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, dimethylaminoethyl ( (Meth) acrylate, benzyl (meth) acrylate, carbitol (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, 2-hydroxyethyl (meth)
Acrylate, 2-hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylamide, N-methylol (meth) acrylamide, styrene, acrylonitrile, N-vinylpyrrolidone, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene Glycol diacrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,4-butanediol diacrylate, 1,6- Hexanediol di (meth) acrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, trimethylolpropane triac Rate, dipentaerythritol hexa acrylate, phenoxyethyl acrylate, nonylphenoxy acrylate, tetrahydrofurfuryl-oxy acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, ethylene oxide (EO) modified methacrylate, phenoxy diethylene glycol acrylate, EO-modified phthalic acid acrylate,
Low molecular weight photopolymerizable compounds such as (meth) acrylates of phenol alkylene oxide adducts, caprolactone-modified neopentyl glycol diacrylate hydroxypivalate, dicyclopentanyl diacrylate, or epoxy acrylates, urethane acrylates, polyester acrylates, etc. High molecular weight photopolymerizable compounds such as alkyd acrylates, modified acrylates of petroleum resins, and unsaturated polyesters. These one
Species or mixtures of two or more are used.

As the thermoplastic resin (organic polymer binder), it is possible to use a thermoplastic polymer having excellent compatibility with a photopolymerizable compound and having no photopolymerizability. As such a polymer, diallyl phthalate resin (for example, diallyl isophthalate polymer, diallyl orthophthalate polymer,
Hydrogenated products thereof).

It is possible to obtain desired physical properties by adding a polymer other than these thermoplastic substances. For example, the adhesiveness to a support, the adhesiveness to a receptor at the time of transfer, and the abrasion can be improved. Suitable non-thermoplastic polymeric compounds include, for example, phenolic resins, melamine-formaldehyde resins, urethane resins, and the like. In addition, a small amount of filler may be included as a component of the photosensitive layer.
Examples include silica, mica, bentonite and the like, which may be present in appropriate amounts depending on the required properties.

As the photopolymerization initiator, those having less absorption in the visible light region are more preferable. For example, benzophenone, 4,4
-Bis (diethylamino) benzophenone, 4-methoxy-4-dimethylaminobenzophenone, 2-ethylanthraquinone, phenanthraquinone, benzoin, benzoin methyl ether, benzoin phenyl ether, isobutyl benzoin ether, isopropylyl benzoin ether, benzoin ethyl ether , 2,2-diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, 4'-isopropyl-2-hydroxy-2-methylpropiophenone, p-tertbutyltrichloroacetophenone, Michler's ketone, benzyldimethylketal,
2,2-dimethoxy-2-phenylacetophenone, hydroxycyclohexyl phenyl ketone, benzophenone, azobisisobutylnitrile, 2-chlorothioxazon, 2-methylthioxazon, 2-ethylthioxazon, 2-isopropylthioxazon, etc. It is. These addition polymerization initiators may be used alone or in combination of two or more. However, when two or more are used in combination, the effect on mutual free radicals generated by light absorption should be considered. Further, various sensitizers may be added to improve the rate of addition polymerization.

As the thermal polymerization inhibitor, p-methoxyphenol, hydroquinone, t-butylcatechol, pyrogallol, pyridine, aryl phosphite and the like can be used.

The film thickness of the photosensitive layer may be any of about 0.5 to 5 [mu] m, the appropriate application amount varies depending dyes and or pigments are ^{contained, 0.5g / m 2 ~10g / m} 2 are suitable. In the coating of the present invention, coating was performed using a bar coater or the like.
For example, a spin coater or a similar coater may of course be used.

As a thermoplastic material particularly effective in the present invention, diallyl isophthalate polymer is suitable in consideration of a combination with a suitable ethylenically unsaturated compound.
The appropriate ratio of thermoplastic to ethylenically unsaturated compound depends on the material used, but generally the ratio of thermoplastic to ethylenically unsaturated compound is 40:60 to 90:
If it is between 10, the photosensitive layer surface can achieve a state of slight adhesion or non-adhesion at room temperature. At this time, if adhesiveness remains in the photosensitive layer, registration is difficult. In addition, dust and the like in the environment adhere to the surface of the photosensitive layer, and the image quality as a color proof is significantly reduced. Further, a small amount of a thermal polymerization inhibitor may be added to prevent a dark reaction with time.

Conventionally known dyes and / or pigments contained in the photosensitive layer can be used. Generally, dyes and pigments having the same hue of four colors of yellow, magenta, cyan, and black are required, and metal powder, white pigment, fluorescent pigment, and the like are also used. For color proofing, there are yellow, red, indigo, and black, and a pigment or dye that matches these hues may be selected.

The following are well-known dyes and pigments, but they are only a few examples. Organic pigments or dyes such as azo type, phthalocyanine type, quinacridone type, anthraquinone type, indigo type and methine type, or inorganic pigments. For example, Lionol Yellow GRO (C.I21090, Toyo Ink Manufacturing Co., Ltd.)
No. 1201 Lionol Yellow (〃), No. 1206 Lionol Yellow (〃), Lionol Yellow 1208
(〃), No.1305 Lionol Yellow (C.I121100), No.1
306 Lionol Yellow (〃), No. 1307 Lionol Yellow (〃), Lionol Yellow FG1310 (〃), Lionol Yellow FGN-T (C.I21105), No. 7100 Lionol Yellow (C.I21096), Lionol Yellow NBR (C.I21
108), Brilliant Carmine 6BA (C.I15850: 1), Lionol Red 6B4201 (〃), Lionol Red 7B4401
(〃), Brilliant Carmine 8BA (〃), Lionol Blue FG7330 (C.I74160), Lionol Blue FG7351
(〃), Lionol Blue GX-1 (〃), Mitsubishi Carbon Black MA-7, Mitsubishi Carbon Black MA-100 and the like are preferable. As the coloring substance, these substances may be used alone or in combination of two or more.

These dyes and pigments can be easily mixed and contained in the photosensitive layer by appropriate means.

The appropriate amount of pigment or dye added to the photosensitive layer is 5 to 50% by weight of the total solid content, and when it is less than 5%, the amount of coating film increases to obtain the required concentration. Too much
The transferred image tends to be poor. On the other hand, if it exceeds 50%, the actinic rays are not sufficiently transmitted, which causes soiling.
The coating amount of the photosensitive ^{layer, 0.5g / m 2 ~10g / m} 2, preferably ^{1g / m 2 ~5g / m 2} . There are two types of image exposure: direct exposure of the photosensitive layer and the mask, and exposure and exposure from the support side. There are two types of image exposure. 10g /
Although it may be m ² or more, the direction of the obtained layer is opposite, and it is remarkable in an image containing characters and the like, so that it is difficult to observe.

In addition, it is also effective to provide an appropriate matte treatment to the photosensitive layer to obtain a good texture if necessary.

On the other hand, when image exposure is performed from the support side, the obtained image is a normal image, but the coating amount of the photosensitive layer is 10 g / m ^2.
Above, the transferred image tends to be dirty.

Furthermore, a protective film (cover sheet) on the photosensitive layer
However, as a material suitable as a protective film, as described in JP-A-48-31323, a polyethylene film has a weaker adhesion to a photosensitive layer than a base support such as a polyethylene terephthalate film. Serves as a suitable cover sheet. It is known that in a photopolymerization system, the polymerization rate is changed by oxygen in the air. To prevent this, it is necessary to form a coating film such as polyvinyl alcohol on the colored photosensitive layer. , Or a cover sheet, or both of these methods are effective.
When the thickness is as large as μ or more, the quality of a transferred image is adversely affected. Therefore, in the present invention, a method in which a protective film is laminated is more preferable.

In the present invention, an image forming method in which image exposure is performed from the side of a support (mostly transparent) is preferred. By this method, a positional relationship such as image orientation can be significantly improved, and a method can be provided in which a special intermediate image receptor for correcting image orientation is not required.

In the present invention, in the case of an image forming material having a cover sheet, the transparent support means that after being pressed against the image receiving layer,
The image is exposed from the transparent support side in image exposure.

The cover sheet provided as necessary prevents contamination of the photosensitive layer due to the adhesion of the photosensitive layer to an exposure device when exposing for image formation from the support side, and reduces the influence of oxygen on the photosensitive layer. is there.

In the color proofing work of a printed material to which the present invention is applied, it is necessary to reproduce an image with high accuracy from a film or the like serving as an original. At the same time, it is necessary to shorten the time for the color proofing work. In order to satisfy these demands and to ensure a stable quality of the finished image, the accuracy of the reproduced image position and the correspondence between the front and back sides have been improved by a simple work process.
That is, the exposure is preferably performed from the transparent support side.

Hereinafter, the steps of using the present invention, for example, as an image forming material for color proofing will be described step by step.

(1) Provide holes for register pins in the color separation image mask and the image forming material. Further, when the image receiving members are paper or the like, holes for register pins are provided in these image receiving members.

(2) Image exposure, that is, exposure sufficient for curing the image forming material through the color separation mask image to the photosensitive layer using an actinic ray such as ultraviolet rays.

(3) Next, the protective film of the image forming material is peeled off,
The image receiving member is arranged so as to face the peeled colored photosensitive layer surface, and is guided between rollers in a substantially non-contact state. In the nip between the rollers, contact and transfer are performed, and peeling is performed immediately after passing through the nip.

 Usually, transfer is performed under heating as needed.

With one end of the support, the image formed on the photosensitive layer by peeling off the image formed on the photosensitive layer is applied to the image receiver by a preset amount of 1/2 or an appropriate amount in the thickness direction of the film by the internal collecting force. The transfer image is formed.

(4) Post-exposure is performed for the purpose of strengthening the fixation on the entire surface of the transferred image and eliminating the viscosity of the transferred image surface.

The above (1) to (4) are repeated four times (yellow, magenta, cyan, black) in color proofing, for example, to obtain a reproduced image of four colors.

The receiver used in the above is generally used for proof printing, such as art and coated paper, but these examples do not limit the present invention.

The present invention is characterized mainly in the step (3). Unlike the case of pressing and contacting in a planar manner, the contact, transfer and peeling can be performed quickly and stably, and furthermore, the heating In this case, the temperature unevenness is smaller than that in the case of a flat surface.

FIG. 1 is a schematic cross-sectional view for explaining contact, transfer, and peeling between rollers of the present invention.

1 is a platen roller (rubber roller), 2 is a heating roller (gold roller), 3 is a support, 4 is a photosensitive layer, 5 is an image receptor,
Respectively.

The contact and transfer between the photosensitive layer and the image receptor between the rollers is performed by applying pressure and heat. In the case of heating, it is preferable to use heating to such an extent that the used image receptor does not greatly expand and contract. For example, a roller surface temperature of 50 to 150 ° C, preferably 70
Heating at about 110 ° C. gives a preferable result by improving the transfer speed and improving the precision of reproducing fine images. In other words, good transfer can be achieved without causing problems such as swimming and paper waste.

Further, a difference in roller surface temperature can be provided between the rollers. For example, one roller can be heated while the other roller is cooled.

The diameter of each roller is preferably 30 to 500 mm, and the diameter of the two rollers can be changed as well as being the same. When changing the diameter, the roller on the image receptor side is usually enlarged.

The smaller the diameter of the roller, the faster the peeling occurs after the transfer, the peeling can be performed at a temperature close to the set temperature, and a good image can be obtained.

In FIG. 1, the photosensitive layer and the image receptor are guided in a substantially non-contact state between the rollers, contact and transfer are performed at a nip between the rollers, and are separated immediately after passing through the nip.
By this method, good transfer can be efficiently performed without causing problems such as swimming due to excessive heating and temperature drop, and paper waste. In other words, processing between rollers enables processing at a high speed.

As a device for performing the transfer between the rollers, a conventional laminator or the like may be used so that the transfer and peeling in the present invention can be performed.

In the transfer between the rollers in the present invention, the simplest configuration may include only two rollers. For this reason, for example, the heating operation is facilitated, the space for the apparatus is small, and the preparation for work is simple. is there. Further, in addition to the two rollers, an exposure device can be incorporated. Therefore, it is possible to continuously perform the operations from the exposure to the transfer of the image formation.

Further, adjustment of the pressure between the rollers is easy because of the two rollers, and the required pressure can be easily set. In addition, there is an advantage that work can be easily performed with a uniform transfer pressure at all times, and that the obtained image can be made uniform without requiring a skilled person. This is more effective when proof printing is performed by forming a plurality of images from the same original document.

According to the present invention, the complicated work of development due to heat treatment or peeling before transfer as in the prior art is eliminated, and an image having a texture very similar to a printed matter is reproduced on an image receiver such as paper by a simple work.

Hereinafter, the present invention will be described with reference to examples. In the examples, “parts” means “parts by weight” and “%” means “% by weight”.

Example 1 A photosensitive layer solution having the following composition was prepared.

21.23 parts of diallyl isophthalate prepolymer (Daiso Isodap Mn45000, Osaka Soda Co., Ltd.) Dipentaerythritol hexaacrylate DPHA (Nippon Kayaku Co., Ltd.) 7.08 parts Addition polymerization initiator Benzophenone 0.5 parts 4,4 bis-diethylaminobenzophenone (EA B Hodogaya Chemical Co., Ltd.) 0.17 parts Hydroquinone 0.001 part Carbon black MA-7 (Mitsubishi Kasei Kogyo Co., Ltd.) 5.0 parts Toluene 38.0 parts Methyl ethyl ketone 40.0 parts This photosensitive layer solution is biaxially stretched polyethylene terephthalate film. (Film thickness: 12 μm), and a dried film was coated so as to have a thickness of 2.4 μm, and then a polyethylene film was adhered to the coated surface to prepare an image forming material.

The image forming material is image-exposed from the polyethylene terephthalate film (support) side, the polyethylene film as the protective film is peeled off, and the art paper as the image receiving layer and the photosensitive layer are brought into contact at the nip between the rollers. Then, contact, transfer, peeling, and post-exposure were performed by the method shown in FIG. 1, and the result was exactly the same as a normal printed matter (printed matter of this machine).

The feed rate is 50cm / min and the nip pressure between rollers is 4kg / c.
m ² , the temperature of the roller was 50 ° C. for the upper roller and 100 ° C. for the lower roller.

The diameter of the roller is 150 mm for both upper and lower rollers, and the Shore hardness A of the upper roller is 70. The width of the transfer object is 260 mm,
The contact distance and the contact interval are 10 mm.

When the same original was used to form an image four times, and these images were compared, they were all uniform and indistinguishable.

Comparative Example 1 In Example 1, the same image forming material was subjected to image exposure,
After peeling off the protective film and superimposing it on the art paper as the image receptor, using a flat transfer machine (NaoPrinter Mini, manufactured by Naoto Kogyo Co., Ltd.), the temperature is 100 ° C, the pressure is 1kg / cm ² ,
The transfer was performed on a plane under the condition of a transfer time of 1 minute. When the film was peeled at room temperature, the unexposed area was peeled due to paper scuffing, and it was impossible to obtain a constant image.

Comparative Example 2 An experiment was performed by changing the conditions of Comparative Example 1 to a temperature of 100 ° C., a pressure of 4 kg / cm ² , and a transfer time of 1 minute.

Comparative Example 3 In Example 1, the same image forming material was image-exposed,
Peel off the protective film, fix it on the blanket cylinder, roll the blanket cylinder, overlap the art paper as the image receptor, peel it off at the same time as the transfer, and a flat table with a heating device on the paper platen Using a calibrator, temperature 100 ℃,
The transfer was performed under the conditions of a pressure of 4 kg / cm ² and a transfer time of 1 minute.

However, in the obtained image, unevenness in a solid portion and swimming in a halftone dot are seen, and it is not always satisfactory. The difference from the image of this machine printed matter was seen.

In addition, when the images were formed three times and these images were compared, none of them was uniform.

Further, the working space in Comparative Example 3 required about three times or more as compared with the working space in Example 1.

Comparative Example 4 In Example 1, the same image forming material was subjected to image exposure,
After the protective film was peeled off and superimposed on the art paper as an image receiver, it was guided between rollers, and did not peel off immediately after passing through the nip, but peeled off after 5 minutes, causing paper sticking.

Example 2 In Example 1, only the conditions for transfer and separation between rollers were changed.

When the feed speed was 40 cm / min, the nip pressure between the rollers was 2 kg / cm ² , and the temperature of the rollers was 50 ° C. for the upper roller and 90 ° C. for the lower roller, almost the same results as in Example 1 were obtained.

Example 3 In Example 1, only the conditions for transfer and separation between rollers were changed.

When the feed speed was 40 cm / min, the nip pressure between the rollers was 4 kg / cm ² , and the roller temperature was 50 ° C. for the upper roller and 120 ° C. for the lower roller, almost the same results as in Example 1 were obtained.

As in the present invention, the transfer and peeling between the rollers can be efficiently performed to perform good transfer.

Example 4 Instead of carbon black of Example 1, Lionol Yellow FG1310, Carmine 7BFG4412, Lionol Blue FG
In 7330, a photosensitive layer solution was prepared, and an image forming material was obtained in the same manner as in Example 1.

When the image was transferred onto the image receptor of Example 1 in a superimposed manner, a color image was formed.

That is, the same operation was repeated for the remaining three color materials to obtain a color proof in which halftone images were formed in the order of black, cyan, magenta, and yellow.

Furthermore, when the same manuscript was used to form an image four times,
When these images were compared, they were all uniform,
I could not distinguish it.

Example 5 A photosensitive layer solution having the following composition was prepared.

Diallyl phthalate (DAPL Osaka Oxygen) as a polymer and oligoester acrylate (M
Benzophenone / ethyl ketone [benzophenone (Daiichi Kasei / EAB (Hodogaya Chemical)]) was used as an initiator.

As pigments, Lionol Yellow FG1310 for yellow (manufactured by Toyo Ink), Carmine 7BFG4412 for magenta (manufactured by Toyo Ink), Lionol Blue FG7330 for cyan (manufactured by Toyo Ink) or Mitsubishi Carbon MA-7 for black
It was used.

12 parts of polymer was dissolved in 70 parts of MEK, and 12 parts of monomer was mixed with 12 parts of polymer. The initiator is added in an amount of 2.5 to 4% based on the solute of the solution, and the pigment is further added to the solute in the solution.
~ 18% was added to make a photosensitive solution.

Each of these photosensitive solutions is coated on a biaxially stretched polyethylene terephthalate film (25 μm thick) with a bar coater, and dried by irradiating with an infrared lamp (3 kw) for 30 seconds to form a positive color photosensitive solution. Created layers. The coating amount at this time was 5 μm (dry film thickness).

A polyethylene film was laminated on the dried photosensitive layer to form a cover sheet, which was used as an image forming material.

The image forming materials of each of the four colors and the color separation positive films corresponding to these are precisely aligned with register pins, and are then placed in a 1.5 kw ultra-high pressure mercury lamp (manufactured by Camo Denken) for 30 seconds (1
(Equivalent to 00 mj / cm ² ), exfoliated the polyethylene film, transferred between rollers in the same manner as in Example 1 so as to adhere the photosensitive layer to the white paper, further exfoliated, and post-exposed the image. The formation took place. An image having a texture very similar to the printed matter was obtained. The photosensitive layer of the image forming material of Example 2 was transferred about 1/2, and a faithful reproduction image of 50 lines / mm was obtained.

〔The invention's effect〕

 The following effects have been confirmed by the present invention.

In the table, A is good, B is slightly inferior, and C is inferior. In addition,
Image quality was evaluated by observing with a 17.5x magnifier, dot shape, presence / absence of omission, uniformity of density, and presence / absence of swimming.

Furthermore, the film thickness of the image reproduced on an image receptor such as paper has the values shown in the table. When used as a color proofing material, etc., a texture very close to that of printed matter is provided. Cause no trouble. In addition, the surface shape was determined by a micrograph at a magnification of 195 times.

Comparative Example 3 shows that the film thickness is not uniform and unstable.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view for explaining contact, transfer and peeling according to the present invention. 1 is a platen roller, 2 is a heating roller, 3 is a support, 4 is a photosensitive layer, and 5 is an image receptor.

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-62-144993 (JP, A) JP-A-59-83158 (JP, A) JP-A-49-32640 (JP, A) JP-A-59-83640 46639 (JP, A) JP-A-59-84240 (JP, A) JP-B-51-10489 (JP, B1) JP-B-38-9661 (JP, B1)

Claims (1)

(57) [Claims] 1. A dye and / or pigment on a support which is a film or sheet comprising at least one selected from the group consisting of cellulose acetate, polystyrene, polyvinyl chloride, polyethylene terephthalate, polycarbonate, polyimide, and polypropylene, which transmits actinic light;
An image-forming material formed by forming a photosensitive layer containing a photopolymerizable compound and a diallyl phthalate resin as a thermoplastic resin is image-exposed, and the difference in tackiness in transfer between an exposed portion and an unexposed portion of the photosensitive layer. An image forming method for transferring an image based on cohesive failure in which an image formed by image exposure to an image receptor such as paper is not transferred at least in all thicknesses, comprising an exposed image forming material and an image receptor. Respectively, so that the photosensitive layer of the forming material and the image receptor are opposed to each other, and the surface temperature of one roller is 50 to 150 ° C., and the roller is guided between rollers having a diameter of 30 to 500 mm. An image forming method in which transfer is performed in a nip between rollers, and peeling is performed immediately after passing through the nip.