JPH07508474A - Image forming method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] female storm male The present invention relates to direct imaging from a digital source in an electronic configuration. A background that does not accept ink even though it is not wetted by a liquid, i.e. Image form in dry lithography where a lithographic printing plate with non-image area is used Regarding development.

Directly from a digital database of electronic composition, i.e. so-called [computer Forming images using the hanmen system has been a long-standing goal in the printing industry. It was a target. The advantages of such a system over conventional methods of plate formation include: It is.

(i) Eliminating expensive intermediate silver films and processing chemicals; (ii) Saving time; (iii) System automation and associated labor cost reduction.

With the introduction of laser technology, a laser beam is scanned across the surface of the precursor material to create a beam. By modulating the beam to efficiently turn on and off the printing plate precursor. For the first time, the opportunity to form images directly on quality arose. In this way, sensitive polymers A radiation-sensitive plate consisting of a coating produced by a water-cooled UV argon ion laser exposed to a laser beam with a photosensitivity that extends throughout the visible spectrum. Electrophotographic plates use low-power, air-cooled argon ion, helium neon, and semiconductor Exposure was performed using a laser device.

selective (image direction) delamination and subsequent Imaging systems with sand inch structures are also possible, subject to mass transfer. usually , such so-called release systems are used as an alternative to silver halide films. It will be done.

Means to overcome the problems inherent in conventional lithography are also well known and have been The best known form of lithography that uses ink to effectively moisten non-image areas. Uses a lithographic printing plate that does not require wetting the plate with an aqueous solution. This problem is overcome by Usually, such so-called F dry planographic stamp The printing plate is coated with a low surface energy material that is water repellent to printing ink. obtained from a radiation-sensitive plate consisting of a substrate covered with a photosensitive layer covered with Ru. In addition, the ink water repellent layer is applied directly to the substrate, and the photosensitive layer is coated on the ink water repellent layer. It is also possible to do so. Furthermore, for example photosensitive silicone polymers A photosensitive, ink-repellent single layer containing Ru. For example, British Patent Nos. 1,522,228 and 2,034,911 and U.S. Patent Nos. 3,511,178, 3,677.178, and 3.89. No. 4.873, No. 4,225,663, and No. 4,724,195, Several such dry lithography systems have been disclosed.

In general, dry lithographic radiation sensitive plates as described in the prior art are The printed ink is imaged by selectively removing areas of the ink water repellent coating. It exhibits a lipophilic surface that readily accepts. In the case of a two-layer system, this is e.g. positive or By exposing the printing plate to ultraviolet light through a negative photographic transparency, it becomes ink- and water-repellent. This is possible by photochemically changing the tackiness of the layer. Photosensitive layer is ink repellent Positive working when the viscosity of the water layer is strengthened or viscosity increases. Either it is negative working when it is weakened. any place Even if the coating is the least tacky, it can still be developed by developing it in a developer. Can be removed. In addition, the plate surface, which has a single layer that is photosensitive and ink repellent, is exposure to light to harden the image areas and development with a developer to remove the unhardened coating. Can be done.

Although such plates can be used to produce high-quality images, Since it is necessary to expose the image in the image direction, the efficiency of the processing is low. developing Liquid development processes have similar disadvantages.

Digital imaging technology is disclosed in U.S. Patent No. 4,911,075, herein Plate printing plates are generated by spark discharge. In this case, it is applied onto a conductive substrate. A printing plate precursor with an ink-repellent coating containing conductive particles is used; The coating is melted away from the substrate. However, the melt-removable spark discharge is relatively incomplete. Form an image with resolution.

High-resolution melt removal (this property can be improved by using a laser) For example, B, E, Dyer (P, E, Dyer) ( Author)'s paper ``Laser Ablation of Polymers J'' of Po1y+l1ers) (1992 Academic Press (Acad ``Photochemical Processing of Electronic Materials J'' published by emic Preas) Mical Processing of Electronic Mater ials), Chapter 14, pages 359-385). Until recently this method imaging involved the use of high-power carbon dioxide or excimer lasers. but , these lasers suffer from high power consumption rates, excessive costs and high-pressure gas processing systems. Due to this necessity, it is not suitable for use in printing. Due to recent technological advances Therefore, more suitable infrared diode lasers are available, which are compact and Moreover, it is a very economical solid-state device.

Currently, high-power versions of these lasers that can emit up to 3,000 mJ/cm are on the market. has been done.

Coatings that can be imaged by ablation using infrared radiation have been proposed. instructor For example, an image is formed on the receiver sheet by melting away the colored layer in the image direction. A reinforcing film is disclosed in PCT Application No. 90/12342. but, This system requires physical movement of material during the image formation process. Disadvantageously, such methods tend to result in poor image resolution.

The object of the present invention is to avoid the need for any wet processing and to use an infrared diode laser or It is digitally captured using a YAG laser and provides high-resolution images. An object of the present invention is to provide a precursor material for a dry lithographic printing plate that can be used.

A further object of the present invention is to directly remove unnecessary materials rather than transfer them from other substrates. The image is formed by the dry lithographic printing plate surface which can be imaged directly on the printing press. The purpose is to provide precursors.

According to one aspect of the present invention, infrared irradiation covered with a transparent cover sheet In front of a dry lithographic printing plate with a substrate having an ink-repellent coating that can be melted away A trigger substance is provided.

According to other aspects of the invention, (a) Covered with a transparent cover sheet that can be melted and removed by infrared irradiation (b) a dry lithographic printing plate surface precursor comprising a substrate having an ink-repellent coating; The precursor is imaged by directing a beam from an infrared laser onto a continuous area of the coating. Imagewise exposure, the coating melts away in these areas and is ink repellent form an image by losing (c) removing the cover sheet and melt removal product; and (d) applying ink to the image. An image forming method is provided which includes the steps of:

Ink water repellent coating that can be melted and removed by infrared irradiation can be melted and removed by infrared irradiation It can be formed from a single layer with a repellent portion and an ink repellent portion.

Generally, however, the coating will be in at least two layer form, i.e. one or more layers will be coated. The outer layer imparts ink-repellent properties to the coating, while the outer layer imparts ink-repellent properties to the coating. .

Melt removability is achieved by a layer containing a melt removable polymer that also absorbs infrared radiation. Can be granted. We also use melt-removable polymers that do not absorb much infrared radiation. Can be used in conjunction with materials that absorb infrared radiation. In this case, the infrared irradiation absorbing material is melted and removed. It can be provided in the same layer as the removable polymer or in other adjacent layers. usually , can be provided with up to 60% infrared absorbing material, and the coating for the melt-removable layer. The weight of the cover is 0. 1 to 5.0 g/m”.The substrate and melt-removable layer (single or more than one) has ink-receptive properties and is formed by exposure to light. Make the image receptive to ink. Thus, the coating is an ink-repellent compositional element. and a simple mixture of compositional elements that can be melted and removed by infrared radiation, i.e. on a substrate. Can be an interpenetrating polymer network formed in situ . Another example is an ink water repellent monomer and a melt removable monomer with an infrared absorbing material. random blocks on a graft copolymer.

The plate precursor increases the adhesion of the coating to the substrate or increases the adhesion between layers. 1 to increase wear resistance, or otherwise improve system performance. It can additionally have one or more layers.

The substrate used in the present invention may be any substrate suitable for preparing a printing plate. But that's fine. Examples of such substrates include paper, plastic materials, metal or laminated or other materials. 0 dimensional stability with plastic material or paper coated with metal by a suitable method It is advantageous to use a substrate that has sufficient rigidity to maintain . Preferred substrate is metal , plastic, or metal-coated plastic, with the upper side exposed to infrared radiation. High reflectivity for infrared radiation is required to "capture" it in the coating.

Suitable polymers for the melt-removable layer(s) are products that volatilize at ambient temperature. It is a polymer that thermally decomposes to It is clear that a wide range of polymers will work reasonably well. It turned out that. Suitable examples include 1 for example Ister and Fle (jan) (author) “Cellulose” J (C Nitro as described in ellulose and its Derivatives) Self-oxidizing binders such as cellulose and modified nitrocellulose; e.g. ethyl Cellulose, methacrylic polymer and polymethyl methacrylate, polymethacrylate Hydroxyethyl acid, n-butyl polyacrylate, polymethacrylic acid It is a copolymer of lauryl lylate, etc., and most of them are DuPont's elvacite ( Elvacite (trade name) resin or ICI's Neocryl l) Non-self-oxidizing binder commercially available as (trade name) resin; polystyrene and styrene resins such as polyalphamethylstyrene; whose main component is isoprene. Rubber; polyvinyl acetate and polyhydroxybutyric acid; beta-lactone; polylactic acid, rubber Copolymers of polylactic acid with licolic acid and valeric acid and other polyesters; salts Vinyl chloride-vinyl butyrate copolymer; polyurethane; polycarbonate and carbonate Copolymers; copolymers of polysulfone and sulfone, generally acrylic polymers and self-oxidizing polymers are optimal. In addition, what is preferable is the so-called “chemical augmentation”. There is a width J (chemical amplification) type, which is Frechet et al. (Image Science Magazine (J, 1, published in 1986) vol. 30, No. 2, pp. 59-64), Ito and (Washington, AC3, 1984) -, Davidson (T, David3on) (ed.) ACS Symposium Series No. 242, page 11, “Polymer J in Electronics” rsin Electronics), E, Reichmanis manis) and L, F, Thompson (L, F, Thomp3on) (1 Microelectron Engineering Magazine, published in 1991. ic Engineering) Vol. 13, pp. 3-10) et al. .

In these systems, the acidity of certain ester, ether or carbonate moieties Catalytic decomposition generates gases such as carbon dioxide, which regenerates the catalytic acid and provides amplification. .

One particular polymer that meets the structural criteria for chemical catalysis is polypropylene carbonate. (Air Products in Allentown, Pennsylvania) Poly4- t-Butoxycarbonyloxystyrene sulfone, boryl-tert-butoxybutyl Ponyloxy-alphamethylstyrene and PCT Application No. 90/12342 These are various polyurethanes disclosed in . Y, Jiang and Ju. M, J, Frechet (J, M, J, Frechet) (1 Macromolecules, Volume 24, No. 12, published in 9991 3528-3532) and C, G, Wilson (C, G, Wi 1ao n) et al. (IUPAC Bulletin 2nd Forecast published in 1982) also shows that the system is where the edge of the polymer, which has a maximum temperature lower than the surrounding area, is placed on top of the surface. This provides ambient stability. Maximum temperature due to removal of protected group or initiation of decomposition decreases and the polymer undergoes spontaneous decomposition. Examples of such polymers include acetyl Polyphthalaldehyde and polyvinyl carbonate-tert-butyl sulfone on the surface of the Ru.

Must contain a substance capable of sensitizing the melt-removable polymer to infrared radiation In this case, this is a suitable material that absorbs infrared radiation, such as an infrared-absorbing photosensitive dye. Any material may be used, preferably carbon black. commercially available carbs It is particularly preferred to predisperse the black in a suitable binder. Suitable commercial product In terms of quality, for example, both companies are tenants in London, England - KVK (Tennan). t-KVK Ltd. Diapercel available from ) (Trade name) CBJ-A (= Pigment Black 7 in trocellulose) and Ma Magnacryl (Pigment Black 7 in acrylic resin) and Ciba-GeiHy Pigments. ) (Manchester, UK) available from Microl. ith) (trade name) CWA (acrylic resin medium pigment black 7), My Chloris (trade name) CK (vinyl chloride-vinyl acetate pigment black 7) and Microlith (trade name) CA (pigment 7 in ethyl cellulose). , suitable photosensitive dyes include, for example, Plenum, New York, NY, 1990. M. Matsu published by Plenum Preaa. oka) (ed.) A centrally conjugated system as described in “Red [Photopigment]” is appropriate. Squarylium, which can induce deep color migration, CrOConium or other cyanine or cyanine variants It is the body. Infrared-sensitive dyes are manufactured by Sumitomo Chemical (Japan) and Eastman Chemicals (E astman Che+aica1g) (Rochester, New York, USA) It is available from sources such as Photosensitivity to 830nm diode output In contrast, certain screens such as those described in U.S. Pat. No. 5,019,549 Alane dyes are preferred. For YAG laser exposure at 1,064 nm, Shea soap made by American Cyanamicl ( Cyasorb) I R 1 6 5 is preferred. Infrared sensitive dye is carbon It is also possible to mix it with black.

Selective additives to the melt-removable layer include, for example, azodicarbonamide, sulfonyl hydrazide and dinitrosopentamethylenetetramine (Beyer, UK) Forofor (trade name) products available from (Bayer) ), it has substances that thermally decompose into gaseous products (defusing agents). Acid catalyst production When a commercially available degradable polymer is used in the melt-removable layer, thermal decomposition Substances that decompose and produce acids can be added to this layer. These substances include iodonium salts, sulfonium salts and phosphonium salts and 2,6-sinitropenzyl tosila such as salts, sulfonic acid oximes, sulfonic acid dicarboximides and triazines. There are organic esters. These substances are manufactured by Ciba-Geigy. gy) (Manchester, UK), Akzo (France, Longjumeau) and Eastman Kodak Company (U.S. Rochester, New York). Additives that improve coating quality This additive can include fluorinated surfactants (e.g. Zonyl (trade name) surfactant from Pon and Fluora from 3M Fluorad (trade name) surfactant), silicone-based material material (for example, SilWet (trade name) manufactured by Dow Corning) products) and other types of surfactants that are well known. Against the substrate or upper ink repellent layer Additives can be incorporated to improve tack. For these materials, Daukoni Ng (Reading, UK) 21 chlorosilane or has a methoxysilane binder.

The ink repellent properties of the coating depend on the required tenacity, impermeability to gases, and viscosity to the F layer. It is coated with a suitable ink water repellent material that provides adhesion and ink water repellency. This way Such materials include fluoropolymers and silicones such as polydimethylsiloxane. There is a silicone polymer. Preferred months for ink-repellent coatings with the required properties is a silicone oligomer that cures by an addition mechanism. A suitable model for this purpose Silicone oligomers are available from, for example, Dow Corning (Senfe, Belgium). Syl-Off (trade name) manufactured by Syl-Off (trade name) and Thomas Go Redon Yumitz Co., Ltd. (Thomas Goldsch+n1dt AG) (Doy Tsu, erasen)! i! TEGO (trade name) RC. For example, Dow Konin Sil-Off (trade name) 7046 from Gus. Co., Ltd. (considered to be a vinyl siloxane) 30% reactive siloxane polymer) is Dow Corning's Sil-Off (trade name) ) 7048 (95% or more polymethyl hydrogen silicon considered to contain platinum catalyst) Coatable, which is combined with an ink-repellent (loxane) and heat cured to produce an ink-repellent film. mixtures can be produced. Adhesiveness and tenacity of silicone film Enhancing additives are available from Dow Corning, such as Sil-Off ( @species name) 297 (a mixture of acetoxysilane and epoxy functional silane) Sil-Off (trade name) 7210 (60% silico in xylene) controlled release additives, which are resin solvents. Fluoropolymer oligomers are For example, DuPont's (Ilmington, Praue, USA) )) Available as Zonyl (trade name).

If the ink repellent material is present as a separate layer overlaid on the melt-removable layer, the The weight of the water-repellent material coating is 0.1 to 5. 0g/m”, melt-removable materials and Water repellent materials can be applied by spin coating, par coating, dip coating, and reverse coating. Roll coating, gravure coating, knife coating and vacuum evaporation Can be applied continuously onto the substrate by coating techniques such as deposition or plasma deposition .

These layers are baked at 50-180'C for 30 seconds to 10 minutes. or cured by exposure to ultraviolet light if the layer is capable of photocrosslinking. It is possible.

The melt-removable material and the ink repellent material are separately bonded to one layer, and the same layer is (i) (a) suitable solvents such as fluoropolymers or silicone polymers; (b) a melt-removable ink repellent material such as a polysiloxane or (b) a melt-removable material and (11) any combination of ink and water repellent materials, and if necessary, the melting and removal The material includes a material that can be made sensitive to infrared rays. These photosensitive materials are infrared Any suitable material that absorbs infrared radiation, such as an absorbing photosensitive dye. Carbon black is also preferred. Single layer depends on coating quality and adhesion In addition to additives that improve the Acid stripping compounds may also be included. The layer is applied onto the substrate by the coating technique described above; It becomes possible to harden.

The precursor of the dry lithographic printing plate is coated with a transparent cover sheet overlaid on the coated surface. Ru. Thus, if the ink repellent material and melt removable material are separate layers, the sheet is overlaid on the ink-repellent layer. An adhesive layer can be optionally provided between the coating and sheet. can. This cover sheet consists of loosely bonded strips produced in the image area by exposure to light. can be captured and prevented from being released into the environment. and ink Remove debris from the exposed precursor by simply removing the sheet before loading can. The sheet may be made of, for example, polypropylene or polyethylene terephthalate or It can be constructed from any other suitable film material that is transparent to infrared radiation. like this For example, the cover sheet may be as described in European Patent Application No. 323,880. It can be produced from a masking film having a structure and composition. Thickness of The diameter is within the range of 8 μm to 100 μm.

The precursor of the plate surface for dry underprint printing has an anti-reflection layer covering the cover sheet. There is also. Suitable antireflective coatings are described in U.S. Pat. Nos. 3,793,022 and 4.7. 69.306 and has a refractive index of 1.0 to 1.6, preferably about 1.3. do. Suitable materials for inclusion in the antireflection layer include, for example, Zonyl from DuPont There are fluorinated polymers available under the trade name.

The precursor for the dry lithography plate is obtained from a laser operating in the infrared region of the spectrum. imaged by a beam of radiation. Particularly preferred lasers are YAG lasers and e.g. For example, Sanyo's 5DL-7032-101100mW diode. It is a diode laser like a laser, and has an energy of up to 3,000 mJ/cm”. is set to radiate energy into the cladding. coated by exposure to a radiation beam Melting removal occurs, which in turn displaces the water repellent material. and the exposed precursor The loosely bonded strips of texture are easily peeled off along with the cover sheet to remove the underlying ink. Reveal your receptive side. The remaining non-image areas do not accept ink. The image generated is high Indicates resolution.

The following examples illustrate the invention.

Example This example shows that the precursor of the present invention was exposed to an infrared diode laser and dried. It shows that it is possible to apply images that are receptive to lithographic printing inks.

The composition that absorbs infrared rays and melts away is prepared by mixing the following ingredients: to form a homogeneous mixture.

CiverGeigy Microlith (trade name) CWA 30.0g 95% ethanol Aqueous solution 18.0g Distilled water 50.0g Ammonia 2.0g (The binder of Microlith CWA constitutes a melt-removable polymer.) Mixture The viscosity of the mixture was lowered by adding 100.0 g of distilled water, and the mixture Howcolon (trade name) polyester fiber is made using filament material. applied to the rum. The coating is dried in an oven at 100° C. for 90 seconds. dry The coating weight after drying is 1.02 g/m''. Both coating and substrate are dry lithographically printed. Accepts ink.

The composition of the silicone coating is prepared by mixing the following ingredients to form a homogeneous Form a mixture.

Dow Corning Sil-Off (trade name) 7046 5.7g isovar (lso par) (trade name) H59, 3g Dow Corning Silu-off (trade name) 7 048 0.1g (Invar H is a liquid hydrocarbon with a registered trademark) Sili The cone mixture was spin coated into a melt removable layer at 1100RP; Form a silicone protective film with a coating weight of 0°78 g/m. Curing is performed at 40° C. for 5 minutes. Protective film repels dry lithography ink .

The resulting precursor was mounted on a motor-driven drum and was powered by a 30 mW continuous wave for 15 minutes. A scanning diode laser (Shar The image was taken on the coated side using a LTO15MDO (140mW, 828nm) made by Ru.

In this way, multiple precursors are imaged using different energies. This is point by point Changing the rotation speed of the drum changes the exposure time, or so-called "residence time" done by Residence time is 10 μsec (200 mJ/cm”) ~ 3 It is changed at 0 μsec (600 mJ/cm”).

The removable layer melts away from the substrate in the image area when exposed to infrared radiation. the upper silicone layer is removed and the lower silicone layer is removed in the same image area. An ink-receptive material appears. The surface of each exposed precursor is cleaned to remove loose debris. Rub lightly with a cotton cloth soaked in Isopar (trade name) H, then dry. be dried. Then, the dried precursor is applied using a roller applicator. Dry color (Dricolo) from DaiNippon Ink and Chemicals r) Inked by (Trade Name) QS Magenta Ink. Approximately 500m Images formed at J/cm" or above accept ink, while non-exposed The area or the area exposed at less than about 500 mJ/cm" is without ink. be.

Other services In this example, the thickness of the ink water-repellent upper layer can be adjusted to 3 without affecting the photosensitivity or resolution. Indicates that it can be changed by the element.

A composition removable by infrared absorption was prepared as described in Example 1, and Ucolon (trade name) is applied onto a polyester substrate. The weight of the coating after drying is 3 ．． 1g7m''. Both coating and substrate accept dry lithographic ink.

The composition of the silicone coating is prepared by mixing the following ingredients to form a homogeneous Form a mixture.

Dow Corning Sil-Off (trade name) 7046 20.0g Isobar (ls opar) (trade name)) (119,8g Dow Corning Silu-Off (trademark) 7048 0.2g silicone mixture has a melt-removable coating at 1100RP. silicone overcoat with a coating weight of 2.1 g/m” form. Dilute the silicone bath 1:1 with the same weight of Isopar (trade name) H. The experiment was repeated to form a silicone protective film with a coating weight of 0.73 g/m''. do. In each case, the protective film was cured at 1740°C for 5 minutes, Repels dry lithography ink.

The resulting plurality of precursors were mounted on a motor-driven drum and exposed to a continuous wave of 55 mW. A scanning diode laser shaped to emit a 25 micron point (Sanyo 5 DL-7032-101, 100mW, 8302 nm) on the coated side Imaged. The energy radiated into the precursor changes the rotational speed of the drum Changed by This changes the residence time. The residence time is 23 μsec (4 Changed from 00mJ/cm") to 124usec (2,300mJ/cm") be done.

When exposed to light, the infrared absorbing layer melts away from the substrate, removing the upper silicone layer. to reveal the ink-receptive material. In any case, any remaining silicone in the exposed area The total amount of particles and melt-removable polymer particles can be examined under 100x magnification. It is estimated by It is shown in the table below.

To remove the debris, the exposed precursor was washed with cotton soaked in Isopar(TM) H. Rub lightly with a cloth and dry. Then, the obtained plate is applied with a roller applicator. Dry color (trade name) magenta ink from Dainippon Ink and Chemicals The ink is put in. Image area shows discernible differences between two layers of different coating weights The ink is received in the absence of any ink. The resolution of the ink cartridge is 10 It is approximated by inspecting with 0x magnification. The shortest residence time as shown in the table Images taken at time have a resolution of less than 10 microns, while the longest residence time The image size at is increased to about 20 microns.

3.1 g/% residual debris in melt-removable layer Residence time Energy Image size 0.73g/+c" 2.1g/m" (p 5ec) (IIJ/c) (um) Silicone Silicone 207 2 320 20 +0 10 ? 2 803 15 30 50 53 596 +2 30 50 Example 1 This example shows conventional aluminum when exposed by an infrared diode laser. Figure 3 shows a composition being melted away from a printing plate substrate.

A composition that can be melted and removed by infrared absorption can be prepared by mixing the following ingredients: to form a homogeneous mixture.

A, 10% sensitizer Polymethyl methacrylate (Medium molecular weight, Aldrich) 10.8g Civer Gai Microlith (trade name) CA manufactured by Gee Co., Ltd. 1.2g methyl ethyl ketone (MEK) 178.0g Dow Corning 1248 surfactant 3.0mlB, 18% sensitizer Polymethyl methacrylate (Medium molecular weight, Old Rich) 10.8g Microlith manufactured by Civer Geigy (Trade name) CA 2.4g Methyl Ethyl Ketone (MEK) 178.0g Dow Corning 1248 surfactant 3. Oml This mixture at 1100RP Applied to 30 gauge anodized aluminum sheet by centrifugal dehydration. The coating is then dried for 30 seconds at 60°C.

Each mixture is then diluted by adding an amount of MEK equal to the mass of that mixture. The experiment is repeated to form a coated sheet with reduced coating weight. Covering The chip is mounted on a motor-driven drum and delivers a 30 mW continuous wave to a 15 micron point. Scanning diode laser shaped to emit light (Sharp LTO15MD, 40 mW, 828 nm) on the coated side. Residence time is determined by drum rotation speed By changing the degree, 10μs ec (200mJ/cm") - 30μsec (600 mJ/cm”). In some cases, i.e. low energy exposure or If the sensitivity is low, or if both variables are used together, the melting removal will be incomplete and the When the coating is inspected, a rough surface is observed. High energy exposure or high sensitivity, or both When used in conjunction with the variable, the coating is completely melted away and the width of the melted line can be determined. Can also be done.

Typical results are summarized in the table below. M of 4 coatings, it (g/ga) sensitizer% Width of melting removal line Cμm) 200+nJ/cm” 60 axis J/cra’0.4 1 8 5 10 1.0 18 (Incomplete melting removal) 52.1 18 (Incomplete melting removal) 50.4 10 (Incomplete melt removal) 141.1 10 (Incomplete melt removal 72.6 10 (incomplete melting removal) 5 points This embodiment consists of a primer layer, a melt removable layer and an ink repellent top layer. The metallized polyester coated with , which is inked by dry lithographic ink to form a high-resolution image. .

The primer layer is prepared by mixing the following ingredients.

Epikote (trade name) 1004 5g methyl ethyl ketone 　100m1 The primer layer is mylar pre-coated with a 50 nm thick layer using wire bonding material. - (Mylar) (trade name) and dried in an oven at 140°C for 30 seconds to reach a dry coating weight of 2.69 g/m''.

A composition that can be melted and removed by infrared absorption can be prepared by mixing the following ingredients: Manufactured.

Polymethyl methacrylate (Low molecular weight, Old Rich) 20g Microlith (trade name) Black CK 5g methyl ethyl ketone 100ml This mixture was applied onto the primer layer using a wire bonding strip and heated at 140°C for 30 seconds. It is dried in an oven to reach a dry coating weight of 3.17 g/m''.

The ink repellent layer is created by mixing the following ingredients until a homogeneous mixture is formed. It is prepared by

Dow Corning Sil-Off (trade name) 7046 20.0g Isopar (trade name) name) H40,0g Dow Corning Sil-Off (trade name) 7048 Q, 5g Dow Corning SIL-OFF (trade name) 297 0.2g This mixture is undercoated using a wire connection material. and cured in an oven at 140° C. for 2 minutes. ink The dry coating weight of the water-repellent layer is 0.83 g/m''; this coating Repel.

The precursor obtained is exposed by an infrared laser according to Example 1. 600 mJ/am'', the coating is melted away. When magnified 100 times, the melt The ablated region can be observed as a well-defined line less than 10 μm wide. This edition Wipe with a cloth soaked in Baichi Isopa (trade name) and dry at room temperature. Ru.

When dry lithographic ink is applied according to Example 1, five image areas receive ink. , on the other hand, unexposed areas repel ink.

Last year's report This example, along with a dry lithographic top layer, is a melt-removable material with improved photosensitivity. Indicates the use of layers.

A composition that can be melted and removed by infrared absorption is prepared as follows: .

Microlith (trade name) Black CK 5g Methyl Ethyl Ketone 100ml This mixture was prepared using Mylar (trade name) as used in Example 4 using a wire tie. ) applied to coated aluminum. This coated film was heated to 140'C for 30 seconds. Dry in an oven. The weight of the coating is 0.17 g/m''.

Then, the coating film was formed with an ink water repellent layer to form a protective film according to Example 4. , the obtained precursor is exposed to an infrared laser according to Example 1. 200mJ /cm', the infrared absorbing layer is melted and removed, leaving an ink-repellent protective film. Remove. When observed under a microscope, the melted removal area is clearly defined with a width of 10 μm or less. It can be observed as a curved line. When dry lithographic ink is applied according to Example 1 , the melt-absorbed areas accept the ink, while the unexposed areas repel the ink.

100,000,000 A composition that can be melted and removed by infrared absorption can be prepared by mixing the following ingredients: to form a homogeneous mixture.

Dispersel (trade name) CBJ-A 2. OgMEK 8.0g This mixture was prepared using Howcolon (trade name) polyester using a No. 5 gauge wire connection strip. applied on top and allowed to air dry for 5 minutes. This reduces the weight of the dry coating. A coating of approximately 1.0 g/m'' is formed.

The silicone coating composition is prepared by mixing the following ingredients to form a homogeneous mixture. (Isopar G is a liquid hydrocarbon with a registered trademark) Dowco Sil-Off (trade name) 7046 manufactured by Dow Corning Co., Ltd. 20.0g Luoff (trade name) 7048 0.05g Siluoff (trademark) manufactured by Dow Corning name) 297 0. 5g Silu-off (trade name) 7210 manufactured by Dow Corning 5.0g Isopar (trade name) G 40.5g The silicone mixture is applied to the melt-removable layer using a No. 8 gauge wire strip; Cured for 3 minutes at 130°C. The resulting precursor was cut into two pieces and prepared as Example 3 It is attached to the motor-driven drum of the writing device described in . transparent on one precursor. A cover sheet in the form of a clear adhesive superimposed film is applied. on the other precursor A non-adhesive 8 μm Mylar (trade name) cover sheet is taped to the top.

Both precursors are then exposed as described in Example 3. adhesive cover sheet When the film is removed, the melted away dye, residual polymer and film are melted away. An image made of removed silicone and written by a laser appears.

Non-tacky cover sheets produce much less sharp images. wipe away loose debris The two exposed precursors are inked as described above and the inked precursors are The printed image is then contact-transferred to smooth paper. Precursor with adhesive cover sheet The material prints clear images, while the precursor with a non-stick cover sheet does not Prints clear patched images. In this way, the adhesive cover sheet can be melted and removed. Captures dislodged material while simultaneously removing loose debris and eliminating the need for cleaning steps. It is an excellent means of The adhesive cover sheet also retains a copy of the stamped image and protects it from exposure. Allows for light confirmation.

Oshimasue This example shows that the dry lithographic printing plate precursor of the present invention is We show that imaging is possible with continuous wave infrared diodes in the device.

A composition that can be melted and removed by infrared absorption can be prepared by mixing the following ingredients: to form a homogeneous mixture.

Dispersel (trade name) CBJ-A 2. OgMEK 8.0g This mixture was prepared using Howcolon (trade name) polyester using a No. 5 gauge wire connection strip. was applied and allowed to air dry for 5 minutes so that the weight of the dry coating was approximately 1.0 g. /m” coating.

The silicone coating composition is prepared by mixing the following ingredients to form a homogeneous mixture. form a compound.

SIL-OFF (trade name) 7046 20.0g SIL-OFF (trade name) 7048 0 ．． 5g Sil-Off (trade name) 297 0.2g Isopar (trade name) G 40. O g The silicone mixture is applied to the melt-removable layer using a No. 8 gauge wire strip; Cured for 3 minutes at 130°C. A mylar cover sheet is then applied.

The obtained precursor was irradiated with 32 arrays of infrared lasers (sunshine) emitting at 830 nm. Yaw Semiconductor, 5DL-7032-102, Allenzol, New Chassis ( Provided by CREO (Vencouve 7-BC) using The supplied writing device is exposed to light through a cover sheet, and an input of 130 mJ/cm” is applied. Screen text putter with 150 lines using radiant laser energy generate the

The imaged precursor was removed from the drum and moistened with Isopar H. Any loose debris is wiped away. The resulting printing plate was inked and inked as described above. The inscribed image is contact transferred to smooth paper. A recognizable image is printed .

Inusei Bandan Example 6 is an adhesive overlay of Auto+nask (trade name) material. It is repeated by using it as a film. Automask (trade name) is #Ii for lithographic printing, and masking when preparing stencils for screen printing Autoty International Co., Ltd. (Autoty International Co., Ltd.) This is a laminate product supplied by PERNTSRNATIONAL LTD. Ru.

The adhesive red coating is peeled off from the base film and affixed to the surface of the ink repellent layer. It will be done. The precursor is exposed and the film removed as described in Example 3. formed The plate surface has no loose debris and does not require a cleaning step before printing.

The film's adhesive is based on natural rubber, and contains alpha terpene resin to improve viscosity. was added, and the peeling measured at an angle of 180° during peeling of the membrane and base film. The detachment resistance was 37 to 70 gm per 30 mm sample width.

Real color dendan Example 6 is repeated using a cover sheet placed in natural position. natural rubber melt (12 g) and alpha terpene resin (100 g) in a hydrocarbon solvent (5° 000ml) of the melt-removable precursor aggregate described in Example 6. An adhesive sublayer is formed by coating on the surface of the silicone layer. When drying, Aliphatic polyurethane resins and A composition consisting of a nitrocellulose and a nitrocellulose solvent was applied to the adhesive layer at a thickness of 30 microns. clothed.

The precursor is exposed as described in Example 3. Cover sheet is removed and printed A plate that does not require a cleaning process beforehand is produced.

Claims (10)

[Claims] 1. The ink is covered with a transparent cover sheet and can be melted and removed by infrared irradiation. A precursor for a dry lithographic printing plate having a substrate with a water-repellent coating. 2. The coating may be a material that can be melted and removed by infrared irradiation, or an ink-water repellent material. The printing plate precursor according to claim 1, which has a single layer shape. 3. The coating has a layer made of a material that can be melted and removed by infrared irradiation and is ink water repellent. 2. The printing plate precursor according to claim 1, having an outer layer consisting of a material. 4. The material that can be melted and removed by infrared irradiation is a polymer that can be melted and removed by infrared irradiation. The printing plate precursor according to claim 2 or 3, further comprising a radiation absorbing material. 5. The melt-removable polymer is an acrylic polymer or a self-oxidizing polymer. The printing plate precursor according to claim 4. 6. A claim in which the infrared radiation absorbing material is carpon black or an infrared sensitive dye. 4. The printing plate precursor according to 4 or 5. 7. Any one of claims 2 to 6, wherein the ink water repellent material is a silicone polymer. Plate precursors as described in Section. 8. 8. According to any one of claims 1 to 7, wherein the cover sheet is applied to the coating. Listed plate precursors. 9. (a) Can be melted and removed by infrared irradiation covered with a transparent cover sheet providing a precursor for a dry lithographic printing plate having a substrate having an ink-repellent coating; (b) by directing a beam from an infrared laser onto a continuous area of said coating; imagewise exposing the precursor material to melt away the coating in the area; and form an image by losing ink water repellency, and (c) melting and removing the cover sheet. and (d) applying ink to the image. 10. 10. The method of claim 9, wherein the cover sheet is provided with an antireflection layer.