JPS5921542B2 - Printing plate manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention involves dissolving a photosensitive resin composition and an organic fluorine compound to form a uniform coating composition, applying it to a printing plate substrate, drying it, and applying active rays such as ultraviolet rays through a manuscript film. A method for producing a printing plate that is baked with light and developed using the difference in solubility of the exposed and unexposed areas in each developing medium, leaving an insoluble area and turning the insoluble area into a non-image area to which printing ink does not adhere. It is related to.

More specifically, the photosensitive resin component in the coating composition consisting of a photosensitive resin composition and an organic fluorine compound imparts an image forming effect and an adhesion/wear resistance effect to the organic fluorine compound in the insoluble portion, and the organic fluorine compound Water-repellent, oil-repellent, and mold-releasing effects prevent printing ink from adhering to insoluble areas.

The insoluble area thus produced exhibits printing durability usable for office and commercial printing and the effect of a non-image area that repels printing ink and is non-adhesive. When photo-insolubilized by exposure, the unexposed and uninsolubilized portion, or when solubilized by exposure, the portion solubilized by exposure can be easily and completely removed by being developed with each developing medium. The printing plate substrate portion appears. Printing plate substrates that can be used in the present invention include zinc plates, magnesium alloys, aluminum plates, copper plates, paper, synthetic paper, and the like.

This printing plate base material part sufficiently receives printing ink by an inkider, and is efficiently transferred to an offset blanket cylinder or a printing medium, thereby making it possible to obtain a clear printed matter. The basic printing methods currently in use are letterpress printing,
It is roughly divided into three types: gravure printing and planographic printing.

In letterpress printing, an ink roller applies printing ink only to the convex portions of the printing plate, and the printing ink is transferred directly to the printing material using these portions as image areas and the concave portions as non-image areas. In gravure printing, the image area is the concave part of the printing plate. Printing ink is applied to the entire surface of the printing plate, passed through a doctor blade, leaving the printing ink only in the recesses, and the printing ink in the recesses is transferred to the printing material. In planographic printing, a lipophilic area (image area) and a hydrophilic area (non-image area) are created on a flat printing plate base material, and an ink roller applies printing ink and a water roller applies dampening water to mix water and oil. Taking advantage of the mismatch, the printing ink image on the oleophilic portion is transferred once to the blanket cylinder and then transferred to the printing medium. Each of the three basic printing methods broadly classified above has developed as industrial printing, but the basics of each printing plate method have not changed and the basic problems of each have continued as they are. First, in letterpress printing, strong pressure is required to transfer the printing ink adhering to the raised parts of the printing plate to the printing medium, so the printing plate material must be strong enough to withstand this pressure, and there are material constraints. big. Metal plates are heavy, and there are also problems such as waste liquid and residue produced by the corrosion process when creating the convex portions. Recently, many letterpress printing plates made of synthetic resin have been developed and are being used for industrial printing, but there are still problems in terms of price, clarity of printed matter, etc. The problems with grapia printing are that the cylinders that serve as the plate base material are extremely expensive, and that plate making requires a high degree of skill. Lithographic printing uses the repellency of water and oil to coat non-image areas with water and image areas with printing ink, so problems such as reduced gloss of printed materials and blurred images due to emulsification of ink with water have been raised. Furthermore, the water dislocated on the offset cylinder wets the printing material, such as paper, causing problems such as curling and dimensional changes. Furthermore, the adjustment of this water is extremely complicated and delicate, and requires a skilled person with many years of experience. Problems with each of these printing methods require improvements and improvements in each technical field.
Through development research, certain problems are being solved.

However, basic questions regarding different printing methods cannot be avoided as long as these printing methods are adopted. Under these circumstances, in recent years, printing methods that are completely different from the three basic types of letterpress printing, gravure printing, and planographic printing have been developed.For example, electrostatic printing that applies static electricity, and There are lithographic printing plates that do not require water, but the former is mostly used for office copying, and the latter is still used due to problems such as a decrease in printing durability due to temperature rise, dislocation of printing ink, and price. It is not commonly used and has only been seen in a small number of practical applications in limited fields. Similar to the present invention, attempts to apply fluorine compounds to printing plate materials were made in Japanese Patent Publication No. 1167-1167 and Japanese Patent Publication No. 493-1989.
6403, but in the former method, a solution of a fluorocarbon surfactant is applied onto a lithographic printing plate that has been baked and developed using a conventional lithographic printing plate manufacturing method, and the metal of this fluorocarbon surfactant and the image area are mixed. Utilizing the difference in selective adsorption between organic substances treated with Lutzka's first-class oil-sensitizing treatment, the non-image area of the fluorocarbon surfactant-coated surface to which printing ink does not adhere, and the oil-sensitizing area to which printing ink adheres. This is a method of printing using the image area, but these methods have problems such as the fact that the adhesion between the fluorocarbon surfactant and the metal is extremely small, and the selective adsorption between the metal and the oil-sensitive area is not so clear. For these reasons, it has the disadvantage that it cannot maintain the abrasion resistance and print clarity that would allow practical printing. The latter uses a completely opposite mechanism to the former by selecting the solution concentration of the organic fluorine compound, but like the former, it is used in practical printing due to problems such as printing durability and unclearness of printing due to unclear selective adsorption. There are drawbacks that cannot be avoided. The present invention was developed by considering the basic problems of letterpress printing, gravure printing, and planographic printing described above, as well as the problems of recently developed products, from a completely new perspective, and conducting various experiments. This is the discovery of a new method for manufacturing printing plates.

The photosensitive resin composition in the present invention may be any of those used for printing plate materials and photo applications, and examples thereof include the following.

(1) Compositions made of polyvinyl cinnamate polymers (e.g., KPR, manufactured by Kodatsu) (2) Compositions made of cyclized rubber polymers or polymers with unsaturated bonds and bisazide compounds (e.g., KMER, manufactured by Kodatsu) ) (3) Compositions using polycinnamylidene acetate-based polymers (e.g., manufactured by Kodatsu Co., Ltd., KOR) (4) Compositions of quinone diazide and novolac resin, modified novolatile long-lasting polyvinylphenol, or polyvinyl alcohol (e.g., manufactured by Hoechst Co., Ltd.) (5) Compositions of diazo compounds and novolac resins (e.g., manufactured by Koyo Co., Ltd., Cywaipon Negative) (6) Vinyl monomers and/or vinyl polymers,
Compositions with cellulose derivatives, polyamide polymers, polyvinyl alcohol derivatives, polyacrylate polymers, polyurethane polymers These photosensitive resin compositions may contain sensitizers, polymerization inhibitors, colorants, fillers, etc. 〇An organic fluorine compound h that is made compatible with the above photosensitive resin composition.The compatibility results in a uniform coating composition, and when it is applied to a printing plate substrate, it forms a uniform coating film. must be formed.

Furthermore, the coating composition film formed by baking and development must exhibit the effect of completely repelling ink in the non-image area.Compatibility with the photosensitive resin required for the present invention, printing As a result of intensive research on the synthesis of various organic fluorine compounds from a new perspective regarding water repellency, oil repellency, mold release properties, etc. when used as a printing plate, we have synthesized an organic fluorine compound that is fully compatible with the purpose of the present invention. succeeded in.

Typical organic fluorine compounds used in the present invention include the following. In order to impart sufficient water repellency, oil repellency, and mold release properties to addition copolymers with unsaturated compounds, the number of carbon atoms in the perfluoroalkyl group in the compound is preferably 3 to 21, and the number of carbon atoms in the perfluoroalkyl group in the compound is preferably 3 to 21. In order to impart compatibility, compounds or polymeric compounds having functional groups such as ester groups, sulfonamide groups, phosphate ester groups, and oxyalkylene groups are desirable.

The concentration of the fluorine compound added to the photosensitive resin is 0.01
The proportion is ~10%, preferably 0.1-2%. If it is added too concentrated, it will not be effective and will not be economical. Further, in the present invention, the printing plate base material part serving as the image part is made of metal plates, synthetic resin films, paper, etc., which have been conventionally used as printing plate base materials. If particularly necessary, surface treatment of the substrate may be performed to improve the adhesion of the coating composition and further to improve the affinity for printing ink as an image area. The coating composition of the present invention described above, which is produced by uniformly dispersing and dissolving the photosensitive resin composition and the organic fluorine compound, is stable over time and can be applied to printing plate substrates extremely easily. And it can be applied evenly.

The coating method may be a coating method used in general printing plate manufacturing. For example, the thickness of a coating film formed by coating with a wheal coater, roller coater, dipping, etc. is 0.1 to 20 microns, preferably 0.5 to 10 microns. Drying can be done at room temperature, but drying with moderate hot air will increase work efficiency. It is also desirable to carry out these operations under a safe light for photosensitive resins. The printing plate substrate to be coated with the coating composition should be completely washed to remove oil stains, dust, etc. Furthermore, in order to improve the adhesion with the coating composition and further improve the affinity of the printing ink as an image area, the metal plate is subjected to grain treatment, anodization treatment, and surface treatment using resin coating compositions such as epoxy, acrylic, and polyester. For synthetic resin films, it is effective to perform surface treatments such as corona discharge treatment, ozone treatment, and oxidizing chemical treatment, and for paper, various treatments such as surface treatment with epoxy, vinyl, acrylic, and other resin coating compositions are effective. The printing plate coated with the coating composition of the present invention and dried is printed using a negative or positive original film depending on the photosensitive resin composition used.

However, since the insoluble area becomes a non-image area during printing, a negative or positive original is selected with this point in mind. Baking is performed using active light such as ultraviolet light. High-pressure mercury lamps, pulsed doxenon lamps, carbon arc lamps, etc. are used as ultraviolet light sources. Development is carried out using different developing solutions depending on the photosensitive resin used. When a water-soluble photosensitive resin composition is used, fresh water, alkaline aqueous solution, alcohol, etc. may be used alone or in combination. Other photosensitive resin composition systems include aromatic systems such as toluene and xylene, ketone systems such as acetone methyl ethyl ketone, ester systems such as ethyl acetate and cellosolve, alcohol systems such as methanol, ethanol, and glycol, and chlorine systems such as chlorocene and trichloroethane. These systems can be used alone or as a mixture. Furthermore, surfactants may be added to these developing solutions as necessary to increase the development speed.

The developing method may be a method used in lithographic printing plates, photosensitive resin plates, and photo applications.

Printing plates made by these methods have insoluble areas as non-image areas, allowing clear printing and practical printing durability. The printing plate of the present invention uses a metal plate such as an aluminum plate, a zinc plate, or a magnesium plate with a thickness of 0.1 to 0.5 mm, synthetic paper, or paper as a printing plate base material, and coats the coating composition thereon with 0.1 to 0.5 mm thickness. 5-1,0
Since it is coated to a thickness of μ, it is lightweight and easy to handle. Similar to lithographic printing, printing on the printing material can be performed with a very small printing pressure, and because the printing plate mechanism is flat, the clarity of the printed matter is very high. Furthermore, the greatest effect of the printing plate produced by the method of the present invention is that it can be printed on a lithographic printing press without using dampening water.

This solves the problems of lithographic printing, such as reduced light selectivity and blurring of printed matter caused by emulsification of printing ink by dampening water, and also eliminates curling and dimensional changes in the paper used for printing. In addition, the water-repellent, oil-repellent, and mold-releasing surface, which is the non-image area,
Since the image is sufficiently fixed by the photosensitive resin at the same time as the image is formed, it maintains abrasion resistance that can provide the printing durability required for commercial printing. This printing plate does not require an expensive base material like a gravure cylinder, and since it is a PS plate (pre-sensitized printing plate), it does not require advanced plate-making engineers, so the total plate-making cost is high. resulting in a wide decline. The present invention will be described below with reference to Examples, but it goes without saying that the present invention is not limited thereto and that there are various embodiments within the scope of the gist of the present invention.

The central part of the example is an important part.

Example 1 A photosensitive composition of polyvinyl cinnamate polymer whose exposed portion becomes insolubilized - P1 (KPR manufactured by Kodaku Corporation) and an organic fluorine compound - F1! F,7(CH2)20C-C=CH
2 and a 10% toluene solution of a copolymer of methyl methacrylate in a weight ratio of 1:2] were uniformly dissolved in the following composition ratio to obtain a coating composition (4).

The coating composition (4) was coated with a roller coater to a thickness of 0.
．． Uniformly coat a 5m11 zinc plate to a film thickness of approximately 3μ.
After drying at room temperature, print using a positive original. The baking conditions are 50CT using a high pressure mercury lamp (3Kw) as the light source! l
Expose for 60 seconds from a distance of Development is performed using a KPR developer in a predetermined manner. The photo-insolubilized non-image area produced by development becomes water-repellent, oil-repellent and releasable due to the organic fluorine compound contained therein, and completely repels printing ink. The printing plate made in this way was mounted on a lithographic printing machine (manufactured by Color Metal Co., Ltd., Pearl) at a rate of 600 per hour, excluding the dampening water device.
We were able to print at a printing speed of 0 pages and obtain over 10,000 clear prints.

Example 2 Photosensitive composition of a cyclized rubber polymer and a bisazide compound whose exposed areas become insolubil-P2 (manufactured by Kodatsu Co., Ltd., KMER) and an organic fluorine compound-F2CC8Fl7S
O2N-(CH2CH2O),0H] were uniformly dissolved in the following composition ratio to obtain a coating composition (B).

The coating composition (8) was coated with a roller coater to a thickness of 0.
．． 5mT! Coat L grain-treated zinc plate uniformly to a film thickness of about 5 μm. After drying with warm air at 50'C, printing is performed using a positive original.

The baking conditions were 50°C using a high pressure mercury lamp (3Kw) as the light source.
Expose for 60 seconds from CTII distance. Development is carried out using a Kbo developer in a prescribed manner. The photosolubilized non-image area generated by development becomes water-repellent, oil-repellent, and releasable due to the organic fluorine compound contained, and completely removes printing ink. Haku.

The printing plate made in this way was attached to a lithographic printing machine (Pearl, manufactured by Color Metal Co., Ltd.) and was printed at 6 pm per hour, excluding the dampening water device.
We were able to print at a printing speed of 1,000 pages and obtain over 10,000 clear prints. Example 3 Quinonediazide and novolak resin photosensitive resin composition-P3 (manufactured by Kareichi Co., Ltd., Coping Glatka-1 PK-13) and organic fluorine compound-F3 [CnF] in which exposed areas are solubilized
2n. +1CH2CHCH2(1)C-CH2(n=9
, 11, 13 in a ratio of 4:2:1) and a 10% butyl acetate solution of a copolymer of 2-ethylhexyl methacrylate and glycidyl methacrylate in a weight ratio of 2:1:1] in the following composition ratio. This was dissolved to obtain a coating composition (C).

The above coating composition (C) was coated with a roller coater on a 0.5 mm thick aluminum plate that had been anodized, with a film thickness of about 4 mm.
Coat μ evenly.

After drying at room temperature, print using a negative original. The printing conditions were a high pressure mercury lamp (3Kw) as a light source and exposure for 50 seconds from a distance of 50 cm. Development is carried out using a Coping Racka developer in a prescribed manner.

The insoluble part, which becomes the non-image part produced by development, becomes water-repellent, oil-repellent, and releasable due to the contained organic fluorine compound, and completely repels printing ink. The printing plate made in this way is attached to a lithographic printing machine (Pearl manufactured by Gala Metal) and printed at a printing speed of 6,000 sheets per hour, excluding the dampening water device, to obtain more than 10,000 clear prints. I was able to do it. Example 4 A 50% isopropyl alcohol solution of a diazo compound whose exposed area becomes insolubilized and a novolak resin-based photosensitive resin composition-P4 (a mixture of P4 (manufactured by Koyo Co., Ltd., Sanwaipon Negative) and an organic fluorine compound 21) was prepared in the following composition ratio. They were uniformly dissolved to form a coating composition (self).

The above coating composition 9 is uniformly coated to a thickness of about 3 μm on a grain-treated aluminum plate having a thickness of 0.3 mm.

Claims (1)

[Claims] 1 A photosensitive resin composition and a carbon number 3 that is compatible with the photosensitive resin composition.
A water/oil repellent comprising an organic fluorine compound having ~21 perfluoroalkyl groups and a functional group selected from the group consisting of ester groups, sulfonamide groups, phosphate ester groups, and oxyalkylene groups. - A method for producing a printing plate characterized by applying a photosensitive coating composition with mold release properties to a base material, exposing it to light, and then developing it to make the insolubilized area a non-image area to which printing ink does not adhere.