JP2000056462A - Heat mode sensitive image forming element for forming positively active printing plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the heat mode image forming element for forming a lithographic printing plate wide in development latitude and high in resolution and enhanced in physical and chemical resistance. SOLUTION: This heat mode sensitive image forming element is used for forming the lithographic printing plate obtained by forming a first layer containing a polymer soluble in an aqueous alkaline solution and an uppermost layer sensitive to infrared rays and impermeable to an alkaline developing solution on the same side of a lithographic base having a hydrophilic surface, and these 2 layers may be the same layer. This uppermost layer contains at least one kind of compound having an epoxy unit in an amount of 20-500 mg/m2 and a hardening agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION This invention relates to heat mode imaging elements for making lithographic printing plates containing an IR sensitive top layer.

[0002] More particularly, the present invention relates to heat mode imaging elements for making lithographic printing plates having better physical properties.

[0003]

BACKGROUND OF THE INVENTION Lithographic printing is a method of printing from a specially made surface in which some areas can receive lithographic printing ink, while others do not receive the ink when wetted with water. It is. The areas that receive ink form the printed image areas and the ink-repellent areas form the background areas.

In the field of photolithographic printing, photographic materials are image-wise oily or greasy on a hydrophilic background, in exposed areas (negative-working) or in unexposed areas (positive-working). Receptive to ink.

[0005] Surface lithographic printing plate (surface lit)
ho plates) or planographic printing plates (pl
ananographic printing plate
In the preparation of conventional lithographic printing plates, also referred to as s), a thin layer of the photosensitive composition is coated on a support that has an affinity for water or obtains such an affinity by chemical treatment. Coatings for that purpose include photopolymer layers containing diazo compounds, dichromate-sensitized hydrophilic colloids and various synthetic photopolymers. In particular, diazo-sensitized systems are widely used.

When the photosensitive layer is image-wise exposed, the exposed image areas become insoluble and the non-exposed areas remain soluble. The plate is then developed using a suitable solution to remove the diazonium salt or diazo resin in unexposed areas.

[0007] In another case, printing plates are known that contain a photosensitive coating that, when exposed imagewise, renders the exposed areas soluble. In that case, subsequent development removes the exposed areas. A typical example of such a photosensitive coating is a quinone-diazide based coating.

[0008] Typically, the photographic material from which the printing plate is made is camera-exposed through a photographic film containing the image to be reproduced in a lithographic printing process. Such work practices are cumbersome and labor intensive. On the other hand, however, the printing plates thus obtained are of excellent lithographic quality.

Thus, there has been an attempt to obtain a printing plate directly from computer data representing the image to be reproduced, except for the need for photographic film in the above method. However, the photosensitive coating is not sensitive enough to be directly exposed using a laser. Accordingly, it has been proposed to coat a silver halide layer over the photosensitive coating. The silver halide can then be directly exposed using a laser under computer control. Subsequently, the silver halide layer is developed, leaving a silver image on the photosensitive coating. The silver image then serves as a mask in the overall exposure of the photosensitive coating. After overall exposure, the silver image is removed and the photosensitive coating is developed. Such a method is, for example, J
Although disclosed in PA-60-61 752, it has the disadvantage of requiring complex development and the accompanying developer.

GB-1 492 070 discloses a method of providing a metal layer or a layer containing carbon black on a photosensitive coating. Next, the metal layer is ablated using a laser to obtain an image mask on the photosensitive layer. The photosensitive layer is then entirely exposed by UV-light through an image mask. After removing the image mask, the photosensitive layer is developed to obtain a printing plate. However, this method still has the disadvantage that the image mask must be removed by a cumbersome process before developing the photosensitive layer.

In addition, methods for making printing plates involving the use of imaging elements that are heat-sensitive rather than light-sensitive are known. A particular disadvantage of the photosensitive imaging element as described above for the preparation of a printing plate is that it must be shielded from light. Furthermore, they have sensitivity issues in terms of storage stability, and they exhibit relatively low resolution. There is a clear trend in the market towards heat mode printing plate precursors.

For example, Research in January 1992
h Disclosure no. No. 33303 discloses a heat mode imaging element comprising on a support a crosslinked hydrophilic layer containing thermoplastic polymer particles and an infrared absorbing pigment such as carbon black. Imagewise exposure to the infrared laser causes the thermoplastic polymer particles to coagulate imagewise, thereby rendering the surface of the imaging element ink-receptive in these areas without further development. A disadvantage of this method is that the resulting printing plate is easily damaged, since it can become ink-receptive if some pressure is applied to the non-printing areas. Furthermore, under marginal conditions,
The lithographic performance of such a printing plate may be poor, and thus such printing plate has little lithographic latitude.

[0013] US-P-4 708 925 discloses an imaging element comprising a photosensitive composition containing an alkali-soluble novolak resin and an onium-salt. The composition may optionally contain an IR-sensitizer. The imaging element is UV-visible- or IR-
After image-wise exposure to lines and a subsequent development step with an aqueous alkaline solution, a positive or negative working printing plate is obtained. The printing results of the lithographic printing plate obtained by irradiation and development of the imaging element are inferior.

[0014] EP-A-625 728 discloses an imaging element comprising a layer which is sensitive to UV- and IR-radiation and which can be positive or negative working. This layer is made of resole resin, novolak resin,
Includes potential Bronsted acids and IR-absorbing materials.
The printing results of the lithographic printing plate obtained by irradiation and development of the imaging element are inferior.

US-P-5 340 699 is EP-
Almost the same as A-625 728, but discloses a method for obtaining a negative working IR-laser recording imaging element. The IR-sensitive layer is a resole resin,
Includes novolak resins, latent Bronsted acids and IR-absorbing materials. The printing results of the lithographic printing plate obtained by irradiation and development of the imaging element are inferior.

Further, EP-A-678 380 discloses a method of providing a protective layer on a roughened metal support under a laser-ablationable surface layer. When image-wise exposed, the surface layer is completely ablated as well as some portions of the protective layer. The printing plate is then treated with a cleaning solution,
The remainder of the protective layer is removed, thereby exposing the hydrophilic surface layer.

EP-A-97 200 588.8 describes
An interlayer comprising a polymer soluble in aqueous alkaline solution and a top layer sensitive to IR radiation on a lithographic base having a hydrophilic surface, wherein said top layer is aqueous alkaline upon exposure to IR radiation. Disclosed are heat mode imaging elements for making lithographic printing plates wherein the volume permeated and / or solubilized by the solution is reduced or increased.

EP-A-97 203 129.8 and EP-A-97 203 132.2 are lithographic bases having a hydrophilic surface and are sensitive to IR radiation, contain polymers which are soluble in aqueous alkaline solutions and Disclosed is a heat mode imaging element comprising a top layer that is impermeable to an alkaline developer containing SiO ₂ as a silicate.

The last three heat mode imaging elements have the disadvantage of their low physical and chemical resistance. While having the simple processing of the last three heat mode imaging elements, heat mode imaging elements with increased physical and chemical resistance would be of value.

[0020]

OBJECTS OF THE INVENTION It is an object of the present invention to provide a wide development latitude (latti
It is to provide a heat mode imaging element for the preparation of a lithographic printing plate having a tude of development.

It is an object of the present invention to provide a heat mode imaging element for making a lithographic printing plate having a high resolution.

It is a further object of the present invention to provide a heat mode imaging element for making a lithographic printing plate with improved physical and chemical resistance.

Further objects of the present invention will become clear from the description hereinafter.

[0024]

SUMMARY OF THE INVENTION In accordance with the present invention, a first layer containing a polymer soluble in an aqueous alkaline solution on a lithographic base having a hydrophilic surface and an IR-on the same side of the lithographic base as the first layer.
A heat mode imaging element for making a lithographic printing plate, comprising a top layer that is sensitive and impermeable to an alkaline developer, wherein the first layer and the top layer can be one and the same layer. There is provided a heat mode imaging element characterized in that the top layer contains at least one compound in an amount of ²⁰ to 500 mg / m2 containing epoxy units and a hardener.

[0025]

DETAILED DESCRIPTION OF THE INVENTION The top layer is also called the second layer. The top layer of the heat mode imaging element of the present invention comprises at least one compound containing an epoxy unit.

As the compound having an epoxy unit, the most important kind of epoxy resin industrially can be used. These polymers are made by the condensation of epichlorohydrin with bisphenol A or F.

However, thermoplastic resins or thermosetting resin-modified polymers containing epoxy units can also be used. Commercially available products include epoxy novolak resin, rubber modified epoxy resin, butadiene-acrylonitrile polymer modified epoxy resin, polyester resin based on bisphenol A, epoxidized o-cresol novolak, urethane modified epoxy resin, phosphate modified Polymer such as modified bisphenol A epoxy resin.

These polymers can have various molecular weights, so that they can be liquid, semi-solid or solid products. These products can also be used as dispersions in liquids such as water or other solvents.

Functionality is a very important parameter in terms of crosslinking behavior. This is expressed as epoxide equivalent weight (weight of epoxy functionality per molecular weight). This is a measure of the potential crosslink density of the polymer. The epoxide equivalent is preferably comprised between 0.03 and 0.8, more preferably between 0.05 and 0.6.

The above epoxy resin can be hardened using various compounds. Most preferred compounds are those belonging to the group of amines, preferably low viscosity amines. These can be monomolecular amines or they can be polymeric products containing amino groups.

As monomolecular amines, ethylenediamine,
Amines such as diethylenetetramine, dipropylenetriamine, monomethanolamine, diethanolamine, triethanolamine, dimethylethanolamine, 2- (2-aminoethoxy) ethanol, morpholine, N-methylmorpholine, and N-ethylmorpholine can be used. . Propylamines such as dimethylaminopropylamine, aminopropylmorpholine, and methoxypropylamine can also be used. Piperazines such as N-aminoethylpiperazine are also effective hardeners. Other suitable amines are cycloaliphatic polyamines, such as isophoronediamine, aromatic polyamines or araliphatic polyamines.

[0032] Polymeric amines are also suitable amines.

A very preferred type of epoxy-hardener is a polyoxyalkyleneamine. These are commercially available in a wide range of molecular weights as monoamines, diamines and triamines. The polyether backbone can be based on propylene oxide, ethylene oxide or mixed propylene oxide / ethylene oxide.

Modified products of basic amines, such as polyaminoamides, Mannich bases, polyether modified amines, preferably polyetherdiamines, urethaneamines, polyetherurethaneamines, polyamides, dimerized fatty acid-polyamine reaction products Preferred hardeners.

2-Methylimidazole is also preferred as a hardener for compounds having an epoxy function. This results mainly in the homopolymerization of the epoxy function. Imidazole can be used as such or in combination with other amines or hardeners. It is preferably used in an amount of 1 to 10 mol% of the epoxy units.

[0036] Trimethylsilane-modified polyethyleneimine is also a preferred hardener. Preferably it is used in an amount of 2 to 90 weight percent based on the epoxy content.

[0037] The top layer may also contain a coupling agent. In this case, the coupling agent is considered to be a molecule comprising at least two groups having different affinities for different compounds in the top layer. Typical products have amine or derivatized functional groups on one side of the molecule and adsorb on carbon black in the case of IR-sensitization with carbon black on the other side of the molecule.
A product having a group that can be Typical products are trialkylsilanes, aminoalkylsilanes, aminoalkylalkoxysilanes such as 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane and 3- (2-aminoethylamino) -propyl-tri Methoxysilane, alkoxysilane, glycidyl ether alkoxysilane, alkoxysilane-modified polyethyleneamine, modified alkoxysilane containing a mercapto group, and isocyanate alkyl trialkoxysilane. These coupling agents are preferably used in an amount of from 5 to 30 mole percent, based on the epoxy content.

In the case of the first embodiment, the first layer and the uppermost layer are different. In such an embodiment, a lithographic base having a hydrophilic surface has a first layer comprising a polymer soluble in an aqueous alkaline solution and a top layer on the same side as the first layer of the lithographic base, the top layer comprising an IR layer. Providing a heat mode imaging element for making lithographic printing plates that are sensitive to radiation and impervious to alkaline developers.

The top layer according to the invention comprises an IR-dye or pigment and a binder resin. Mixtures of IR-dyes or pigments can be used, but it is preferred to use only one IR-dye or pigment. Preferably, the IR
The dye is an IR-cyanine dye; Particularly useful IR-
A cyanine dye is a cyanine dye having two indolenine groups.

Particularly useful IR-absorbing pigments are structurally related to the carbon black, metal carbides, borides, nitrides, carbonitrides, bronze-structured oxides and bronze groups, but without the A component. An oxide, for example WO _2.9 . Conductive polymer dispersions, such as those based on polypyrrole or polyaniline, can also be used. The lithographic performance obtained, and especially the printing durability, depends on the heat sensitivity of the imaging element. In this regard, it has been found that carbon black gives very good and favorable results.

The IR-absorbing dye or pigment is preferably present in an amount of from 1 to 99 parts by weight, more preferably from 50 to 95 parts by weight of the total IR-sensitive top layer.

The top layer can preferably contain as binder a water-insoluble polymer such as a cellulose ester, a copolymer of vinylidene chloride and acrylonitrile, poly (meth) acrylate, polyvinyl chloride, silicone resin and the like. Preferred as a binder is a nitrocellulose resin.

The total amount of the uppermost layer is preferably 0.05 to 1
0 g / m ^2, more preferably in the range of 0.1-2 g / m ^2.

When exposed image-wise, in the top layer, differences in the volume permeated and / or solubilized by the aqueous alkaline solution are created for the alkaline developer of the present invention.

In the present invention, image-wise IR exposure cleans the imaged portions without solubilizing and / or damaging the non-imaged portions during development. The capacity increases to the extent.

Development with the aqueous alkaline solution is preferably carried out within an interval of 5 to 120 seconds.

Between the top layer and the lithographic base, the present invention preferentially 7.5 to 14
First soluble in an aqueous alkaline developer having a pH of
Including layers. The layer is preferably continuous with the top layer,
Other layers can be present between the top layer and the first layer.
The alkali-soluble binder used in this layer is preferably a conventional positive- or negative-acting PS.
-Hydrophobic binders as used in plates, for example novolak resins, polymers containing hydroxystyrene units,
And carboxy-substituted polymers. Typical examples of these polymers are DE-A-4 007 428, DE-A
-4 027 301 and DE-A-4445 820
It is described in. The hydrophobic binders used in connection with the present invention are further characterized by insolubility in water and partial solubility / swellability in alkaline solutions and / or partial solubility in water when combined with cosolvents. I have.

Furthermore, the aqueous alkali-soluble layer is preferably a visible light- and UV-light desensitizing layer. The layer is preferably thermally curable. This preferably visible- and UV-desensitized layer is between 250 nm and 650 nm.
Excluding light-sensitive components that absorb within the wavelength range of, for example, diazo compounds, photoacids, photoinitiators, quinonediazides, and sensitizers. In this way, a printing plate stable in daylight can be obtained.

The first layer is preferably also a low molecular weight acid,
Preferably it contains a carboxylic acid, even more preferably benzoic acid, most preferably 3,4,5-trimethoxybenzoic acid or benzophenone.

The ratio of the total amount of low molecular weight acid or benzophenone to polymer in the first layer is preferably 2: 9.
8 to 40:60, more preferably 5:95 to 20:80
Range. The total amount of the first layer is preferably from 0.1 to
10 g / m ^2, more preferably from 0.3 to 2 g / m ^2.

The first and / or top layer (also referred to as the second layer) preferably contains a surfactant. The surfactant can be a cationic, anionic or amphoteric surfactant, but is more preferably a non-ionic surfactant. Surfactants are most preferably selected from the group consisting of perfluoroalkyl surfactants, alkylphenyl surfactants and particularly preferably polyether-modified polysiloxane surfactants. The surfactant is preferably present in the top layer. The amount of surfactant is preferably 0.00
Within the range of 1 to 0.3 g / m ² , more preferably 0.00
It is contained within the range of 3 to 0.050 g / m ² .

In the imaging element of the present invention, the lithographic base for all embodiments can be anodized aluminum. A particularly preferred lithographic base is an electrochemically roughened, anodized aluminum support. The anodized aluminum support can be treated to increase its surface hydrophilicity. For example,
The aluminum support can be silicated by treating its surface with a sodium silicate solution at an elevated temperature, for example, 95 ° C. In another case, a phosphating can be performed, which comprises treating the aluminum oxide surface with a phosphating solution, which can further contain inorganic fluoride.
Further, the aluminum oxide surface can be rinsed with a citric acid or citrate solution. This treatment can be performed at room temperature or at a slightly elevated temperature of about 30-50 ° C. A further interesting treatment involves rinsing the aluminum oxide surface with a bicarbonate solution. In addition, polyvinyl phosphonic acid, polyvinyl methyl phosphonic acid, polyvinyl alcohol, phosphate ester of polyvinyl alcohol, polyvinyl sulfonic acid, polyvinyl benzene sulfonic acid, polyvinyl alcohol formed by reaction with sulfate ester of sulfonated aliphatic alcohol and sulfonated aliphatic aldehyde. It can be processed using acetal. It is further apparent that one or more of these post-treatments can be performed alone or in combination. A more detailed description of these processes can be found in GB
-A-1 084 070, DE-A-4 423 1
40, DE-A-4 417907, EP-A-659
909, EP-A-537 633, DE-A-40
01 466, EP-A-292 801, EP-A-
291 760 and U.S. Pat. No. 4,458,005.

According to another mode associated with the present invention, in all embodiments, the lithographic base having a hydrophilic surface comprises a flexible support, such as a paper or plastic film provided with a cross-linked hydrophilic layer. Including. Particularly suitable cross-linked hydrophilic layers can be obtained from hydrophilic binders cross-linked with cross-linking agents such as formaldehyde, glyoxal, polyisocyanate or hydrolyzed tetra-alkyl orthosilicate. The latter is particularly preferred.

As hydrophilic binders, hydrophilic (co) polymers such as vinyl alcohol, acrylamide, methylolacrylamide, methylolmethacrylamide, acrylate acid, methacrylate acid,
Homopolymers and copolymers of hydroxyethyl acrylate and hydroxyethyl methacrylate or maleic anhydride / vinyl methyl ether copolymer can be used. The hydrophilicity of the (co) polymer or (co) polymer mixture used is preferably the same or higher than that of the polyvinyl acetate hydrolyzed to at least 60% by weight, preferably to the extent of 80% by weight.

The amount of crosslinker, especially tetraalkyl orthosilicate, is preferably at least 0.2 part by weight, more preferably 0.5 to 5 parts by weight, most preferably 1.0 part by weight per part by weight of hydrophilic binder. ３3 parts by weight.

The lithographic base crosslinked hydrophilic layer used in accordance with this embodiment preferably also contains substances that enhance the mechanical strength and porosity of the layer. Colloidal silica can be used for this purpose. The colloidal silica used can be in the form of any commercially available water-dispersion of colloidal silica having, for example, an average particle size of at most 40 nm, for example 20 nm. In addition, inert particles of larger dimensions than colloidal silica, for example, Co
lloid and Interface Sci. ,
Vol. 26, 1968, pages 62 to 6
At least 100 n particles of silica or alumina or particles of titanium dioxide or other heavy metal oxide prepared according to StOber as described in paragraph 9
Particles having an average diameter of m can be added. The introduction of these particles gives the surface of the cross-linked hydrophilic layer a uniform rough texture consisting of microscopic hills and valleys, which serves as a storage for water in the background areas.

The thickness of the lithographic base crosslinked hydrophilic layer according to this embodiment can vary within the range of 0.2 to 25 μm, preferably 1 to 10 μm.

A specific example of a crosslinked hydrophilic layer suitable for use in accordance with the present invention is described in EP-A-601 24
0, GB-P-1 419 512, FR-P-23
00354, US-P-3 971 660, US-P
-4 284 705 and EP-A 514 490.

It is particularly preferable to use a plastic film such as a substrate-based polyethylene terephthalate film, a substrate-based polyethylene naphthalate film, a cellulose acetate film, a polystyrene film, a polycarbonate film, etc. as the lithographic base flexible support relating to this embodiment. . The plastic film support can be opaque or transparent.

It is particularly preferable to use a polyester film support provided with an adhesion promoting layer. Particularly suitable adhesion promoting layers for use in accordance with the present invention are EP-A-619.
524, EP-A-620 502 and EP-A-6
A hydrophilic binder and colloidal silica as disclosed in US Pat. Preferably the amount of silica in the adhesion improving layer is between m ² per 200Mg～m ² per 750 mg. Further, the ratio of silica to hydrophilic binder is preferably higher than 1, and the surface area of the colloidal silica is preferably at least 300 m ² per gram, more preferably at least 500 m ² per gram.

In the case of the second embodiment, the first layer and the second layer are the same. In this embodiment, having a top layer on a lithographic base having a hydrophilic surface, the top layer is sensitive to IR-rays, contains a polymer that is soluble in aqueous alkaline solution, and is impermeable to an alkaline developer. A heat mode imaging element for making a lithographic printing plate is provided.

The IR-sensitive layer according to the invention comprises an IR-dye or pigment and a polymer soluble in aqueous alkaline solution. Mixtures of IR-dyes or pigments can be used, but it is preferred to use only one IR-dye or pigment. Suitable IR-dyes and pigments are those listed above in the first aspect of the invention.

The IR-dye or pigment is preferably present in an amount of from 1 to 60 parts by weight, more preferably from 3 to 50 parts by weight of the total amount of said IR-sensitive top layer.

The alkali-soluble polymers used in this layer are preferably hydrophobic and ink-receptive polymers, such as those used in conventional positive- or negative-acting PS-plates, such as carboxy-substituted polymers. More preferred are phenolic resins, for example polymers containing hydroxystyrene units or novolak polymers. Most preferred are novolak polymers. A typical example of these polymers is DE-A-400
7 428, DE-A-4 027 301 and DE-
A-4445820. The hydrophobic polymers used in connection with the present invention are further characterized by insolubility in water and at least partial solubility / swelling in alkaline solutions and / or at least partial solubility in water when combined with cosolvents. And

Furthermore, this IR-sensitive layer is preferably a visible- and UV-light desensitizing layer. Furthermore, the layer is preferably thermally curable. This preferably visible- and UV-light desensitized layer is between 250 nm and 650 nm.
Excluding light-sensitive components that absorb in the wavelength range of, for example, diazo compounds, photoacids, photoinitiators, quinonediazides, and sensitizers. In this way, a printing plate stable in daylight can be obtained.

The IR-sensitive layer is preferably a low molecular weight acid, more preferably a carboxylic acid, even more preferably benzoic acid, most preferably 3,4,5-trimethoxybenzoic acid or benzophenone, more preferably trihydroxy Also includes benzophenone.

The ratio of total amount of low molecular weight acid or benzophenone to polymer in the IR-sensitive layer is preferably from 2:98 to 40:60, more preferably from 5:95 to 3
The range is 0:70. The total amount of said IR-sensitive layer is preferably 0.1 to 10 g / m ² , more preferably 0.3
２2 g / m ² .

[0068] The top layer preferably contains a surfactant. The surfactant can be a cationic, anionic or amphoteric surfactant, but is more preferably a non-ionic surfactant. Surfactants are most preferably perfluoroalkyl surfactants, alkylphenyl surfactants and particularly preferably polysiloxane surfactants, such as polysiloxane polyethers, polysiloxane copolymers, alkyl-aryl modified methyl-polysiloxanes and acrylates Selected from the group consisting of polysiloxanes. The amount of surfactant is preferably 0.001-0.3 g
/ M ² , more preferably 0.003 to 0.05
0 g / m ² .

When exposed image-wise, a difference in the volume penetrated and / or solubilized by the alkaline developer in the IR-sensitive layer is created for the alkaline developer according to the invention.

For the preparation of a lithographic printing plate, a heat mode imaging element is exposed imagewise and developed.

Image-wise exposure in connection with the present invention is infrared or near-infrared, ie, image-wise scanning exposure involving the use of a laser operating in the wavelength range of 700 to 1500 nm. Most preferred are laser diodes that emit in the near-infrared. Exposure of the imaging element can be performed using a laser having a short pixel dwell time as well as a laser having a long pixel dwell time. Preferred is 0.
A laser having a pixel dwell time of 005 μs to 20 μs.

After image-wise exposure, the heat mode imaging element is developed by rinsing it with an aqueous alkaline solution. The aqueous alkaline solution used in the present invention,
Used for the development of normal positive working presensitised printing plates, preferably containing SiO ₂ as silicates, preferably having a pH of from 11.5 to 14. The imaged portion of the top layer thus exposed and made more permeable to the aqueous alkaline solution is cleaned,
This gives a positive working printing plate.

In the present invention, the composition of the developer used is also very important.

Therefore, what is particularly important for stable development for a long time is the quality such as the concentration of alkali and the concentration of silicate in the developer. Under such circumstances,
The present inventors can carry out rapid high-temperature processing only when using a developer having the above-mentioned composition, the amount of replenisher to be supplemented is small, and it is possible to perform the treatment for three months or more without replacing the developer. It has been found that stable development can be performed over a long period of time.

Preferably, the developing solution and the replenisher for the developing solution used in the present invention are mainly an alkali metal silicate and an alkali metal hydroxide or MOH represented by MOH.
_An aqueous solution containing its oxide, represented by ₂ O, wherein the developer is 0.5 to 1.5 molar ratio and 0.5 to 5
It contains SiO ₂ and M ₂ O at a concentration by weight of SiO ₂ . Suitable as such alkali metal silicates are, for example, sodium silicate, potassium silicate, lithium silicate and sodium metasilicate. On the other hand, preferred as such alkali metal hydroxides are sodium hydroxide, potassium hydroxide and lithium hydroxide.

The developer used in the present invention can simultaneously contain another alkaline reagent. Examples of such other alkaline reagents include ammonium hydroxide, sodium triphosphate, sodium phosphate dibasic, potassium phosphate tribasic, potassium phosphate dibasic, ammonium phosphate tribasic, phosphate dibasic. Inorganic alkaline reagents such as ammonium, sodium bicarbonate, sodium carbonate, potassium carbonate and ammonium carbonate; and mono-, di- or triethanolamine, mono-, di- or trimethylamine, mono-, di- or triethylamine, mono- or Organic alkaline reagents such as di-isopropylamine, n-butylamine, mono-, di- or triisopropanolamine, ethyleneimine, ethylenediimine and tetramethylammonium hydroxide are included.

In the case of the present invention, [SiO_Two] /
[M_TwoOf particular importance is the molar ratio of O]
It is 0.6-1.5, preferably 0.7-1.3. This
If the molar ratio is lower than 0.6, the activity will vary greatly.
Is observed, while if it exceeds 1.5
Imaging becomes difficult and elution of the photosensitive layer on non-image areas
Or, the removal is likely to be incomplete. In addition,
SiO in image solution and replenisher _TwoIs preferably 1 to 4
% By weight. SiO_TwoSuch restrictions on the concentration of
Is excellent even when a large number of plates of the present invention are treated for a long time.
To provide a stable lithographic printing plate with finishing quality
enable.

In a particularly preferred embodiment, 1.0 to 1.5
An aqueous solution of an alkali metal silicate having a molar ratio [SiO ₂ ] / [M ₂ O] in the range of 1 to 4 and a concentration of 1 to 4% by weight of SiO ₂ is used as developer. In such a case, of course, a replenisher having an alkali concentration equal to or higher than the alkali concentration of the developer is used.
In order to reduce the amount of replenisher to be supplied, the molar ratio of the replenisher [SiO ₂ ] / [M ₂ O] is equal to or less than that of the developer or the molar ratio of the developer is lower If it is equal to that of the above, it is advantageous that the concentration of SiO ₂ is high.

In the developing solution and the replenisher used in the present invention, an organic solvent having a solubility in water at 20 ° C. of 10% by weight or less can be used simultaneously if necessary. Examples of such organic solvents are ethyl acetate, propyl acetate,
Carboxylic esters such as butyl acetate, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate, butyl lactate and butyl levulinate; ketones such as ethyl butyl ketone, methyl isobutyl ketone and cyclohexanone; ethylene glycol monobutyl ether, ethylene glycol benzyl Ether, ethylene glycol monophenyl ether, benzyl alcohol,
Alcohols such as methylphenylcarbinol, n-amyl alcohol and methylamyl alcohol; alkyl-substituted aromatic hydrocarbons such as chilesin; and halogenated hydrocarbons such as methylene dichloride and monochlorobenzene. These organic solvents can be used alone or in combination. Particularly preferred in the present invention is benzyl alcohol. These organic solvents are generally added to the developer or replenisher therefor in amounts of up to 5% by weight, preferably up to 4% by weight.

The developer and the replenisher used in the present invention can simultaneously contain a surfactant for the purpose of improving their developability. Examples of such surfactants, higher alcohols (C ₈ ~C ₂₂₎ salts of sulfuric acid esters,
For example, sodium salt of lauryl alcohol sulfate, sodium salt of octyl alcohol sulfate,
Ammonium salt of lauryl alcohol sulfate, T
eepol B-81 (trademark, Shell Chemi)
cals Co. And disodium alkyl sulfates; salts of aliphatic alcohol phosphates, such as sodium salt of cetyl alcohol phosphate; alkyl aryl sulfonates, such as sodium salt of dodecylbenzene sulfonate, isopropyl naphthalene sulfonate. Sodium salt, sodium salt of dinaphthalenedisulfonate and sodium salt of metanitrobenzene sulfonate; sulfonates of alkylamides, for example, C ₁₇ H ₃₃ CON (CH ₃ ) CH ₂ C
H ₂ SO ₃ Na and sulfonic acid salts of dibasic aliphatic acid esters such as sodium dioctyl sulfosuccinate and sodium dihexyl sulfosuccinate.
These surfactants can be used alone or in combination. Particularly preferred are sulfonates. These surfactants are generally present in an amount of up to 5% by weight, preferably
It can be used in amounts up to weight%.

In order to enhance the development stability of the developer and replenisher used in the present invention, the following compounds can be used simultaneously.

Examples of such compounds are neutral salts, such as NaCl, KCl and KBr as disclosed in JN-A-58-75 152; chelating agents such as J.
NA-58-190 952 (U.S.A.-46
9 776) EDTA and NT as disclosed in
A, JN-A-59-121 336 (US-A-46
[Co (N) as disclosed in US Pat.
H _{3) 6]} complex such as _{C1 3; JN-A-55-25} 1
IIa, I of the periodic table such as those disclosed in US Pat.
Ionizable compounds of group IIa or IIIb elements; anionic or amphoteric surfactants, for example JN-A-50-
Sodium alkylnaphthalenesulfonate and N-tetradecyl-N, N as disclosed in US Pat.
-Dihydroxytyl betaine; US-A-4 374
920; non-ionic surfactants as disclosed in JN-A-60-213 943; cationic polymers, such as JN-A-55-95 946. Methyl chloride quaternary product of p-dimethylaminomethyl polystyrene as disclosed
ide quaternary products);
Amphoteric polymer electrolytes, such as JN-A-56-142 25
Copolymers of vinylbenzyltrimethylammonium chloride and sodium acrylate as disclosed in No. 28; reducing inorganic salts such as JN-A-57-192
Sodium sulfite and alkali-soluble mercapto compounds or thioether compounds, such as thiosalicylic acid, cysteine and thioglycolic acid; as disclosed in US-A-4 467 027; inorganic lithium compounds such as JN-A-58- Lithium chloride as disclosed in US Pat.
Lithium benzoate, for example as disclosed in JN-A-50 34 442; JN-A-59-7525
5, an organometallic surfactant containing Si, Ti, and the like as disclosed in JN-A-59-84 241 (U.
Organic boron compounds as disclosed in SA-4500 625); quaternary ammonium salts, for example EP
Tetraalkylammonium oxides as disclosed in A-101 010; and bactericides, for example sodium dehydroacetate as disclosed in JN-A-63-226657.

In the method for development processing of the present invention,
Any known means of replenishing the replenisher for the developer can be used. An example of such a method preferably used is JN-A-55-115039 (GB-A-
JN-A-58-953, a method for intermittent or continuous replenishment as a function of the amount and time of PS plates processed as disclosed in US Pat. No. 2,046,931).
A sensor for detecting the extent of the eluted photosensitive layer as described in US Pat. No. 49 (U.S. Pat. No. 4,537,496) is located in the central part of the development zone and is sensitive to the extent of the eluted photosensitive layer to be detected. A method comprising proportionally replenishing the replenisher; determining the impedance value of the developer solution as disclosed in GB-A-2 208 249, processing the detected impedance value by a computer and processing the replenisher solution It is a method that includes performing replenishment.

The printing plate of the present invention can be used as a seamless sleeve printing plate in a printing method. With this option, the printing plate is soldered in a cylindrical shape using a laser. Instead of applying a classically produced printing plate in a classical way, this cylindrical printing plate having the diameter of the printing cylinder as a diameter is slid over the printing cylinder. For more details on sleeves see "Grafisch Nieuws"
ed. Keesing, 15, 1995, page
4 to 6.

After the image-forming element imagewise exposed is developed using an aqueous alkaline solution and dried, the resulting plate can be used as it is as a printing plate. However, in order to improve the durability, the plate is kept at 200 ° C to 3 ° C.
Baking can also be performed at a temperature of 00C for 30 seconds to 5 minutes. The imaging element can also be subjected to an overall post-exposure to UV-radiation to harden the image and increase the run length of the printing plate.

The following examples illustrate the present invention without limiting it thereto. All parts and percentages are by weight unless otherwise indicated.

[0087]

EXAMPLES Example 1 (Comparative Example) Production of a Lithographic Base Aluminum foil 0.30 mm thick was immersed in an aqueous solution containing 5 g / l sodium hydroxide at 50 ° C. and rinsed with deionized water. Degreased. Then 3
Using alternating current at a temperature of 5 ° C. and a current density of 1200 A / m ² , 4 g / l hydrochloric acid, 4 g / l boric acid and 5 g / l
The foil was electrochemically roughened in an aqueous solution containing 1 aluminum ion to form a surface topology with an average centerline roughness Ra of 0.5 μm.

After rinsing with deionized water, then 300 g /
at 60 ° C. using an aqueous solution containing 1
The aluminum foil was etched for 0 seconds and rinsed with deionized water at 25 ° C. for 30 seconds.

The foil was then placed in an aqueous solution containing 200 g / l of sulfuric acid at a temperature of 45 ° C., a voltage of about 10 V and 150
Anodize at a current density of A / m ² for about 300 seconds to form an anodized film of 3.00 g / m ² Al ₂ O ₃ , then wash with deionized water and contain polyvinylphosphonic acid Work-up with the solution and subsequently with the solution containing aluminum trichloride, and with deionized water
Rinse at 0 ° C. for 120 seconds and dry. Preparation of Heat Mode Imaging Element 8.6% by weight in a 55/45 ratio of tetrahydrofuran / methoxypropanol on the lithographic base first
A layer from the solution was coated with a 14 μm wet coating thickness. The resulting layer is 88% ALNOVOL
SPN452 ^™ (sold by Clariant, Germany) and 12% 3,4,5-trimethoxybenzoic acid.

An IR-sensitive layer was coated on this layer from a 50/50 ratio of a 0.735% by weight solution in methyl ethyl ketone / methoxypropanol at a wet coating thickness of 20 μm. Make this layer at least 120
Dry for at least 40 seconds at a temperature of ° C Obtained IR
The sensitive layer is 115 mg / m ² of carbon black, 1
1.5 mg / m ² nitrocellulose, 2.1 mg / m ²
SOLSPERSE 5000 ^™ , 11.3 mg / m ²
SOLSPERSE 28000 ^TM (both Zen
eca specialties, G. et al. B. Dispersant), 2.0 mg / m ² TEGO WET 265 ^™
And 5.0 mg / m ² of TEGO GIDE 410
^TM (both Tego, Germany polysiloxane surfactant).

Example 2 (Comparative Example) The same base as described in Comparative Example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 0.2720% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer contains 35 mg / m ² of IR-absorber ST7
98 ^™ : 2- (2- (2-chloro-3- (2-dihydro-1,1,3-trimethyl-2H-benzo (e) indole-2-ylidene) -ethylidene) -1-cyclohexene-1- Yl) -ethenyl) -1,1,3-trimethyl-1H-benzo (e) indolium 4-methylbenzenesulfonate, 12.4 mg / m ² FLEXO-B
LAU 630 ^™ , 2.0 mg / m ² TEGO WE
T of 265 ^TM and 5.0mg / m ² TEGO GLI
Contains DE 410 ^TM .

ST798 is Synthon Wolfe
n Commercially available from Germany, F
LEXO-BLAU 630 is from BASF, Ludwig
It is commercially available from Shafen, Germany.

Example 3 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated over this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
25.2 mg / m ² of EPI-REZ 3510 W-
60 ^™ , 29.8 mg / m ² TB 3354H ^™ , 1
1.5 mg / m ² nitrocellulose, 2.1 mg / m ²
SOLSPERSE 5000 ^™ , 11.3 mg / m
² SOLSPERSE 28000 ^™ , 2.0 mg /
TEGO of m ² WET 265 ^TM and 5.0 mg / m ²
Of TEGO GLIDE 410 ^™ .

EPI-REZ 3510 W-60 is S
Aqueous (wat) liquid bisphenol A epoxy resin commercially available at cell Chemicals
erborne) dispersion. TB 3354H is W
It is an amine hardener for water-soluble epoxides commercially available at itco GmbH.

Example 4 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
25.0 mg / m ² of EPI-REZ 3510 W-
60 ^™ , 30.0 mg / m ² EUREDUR 115
^TM , 11.5 mg / m ² nitrocellulose, 2.1 m
g / m ² SOLSPERSE 5000 ^™ , 11.3
1. SOLSPERSE 28000 ^{™ in} mg / m ² ,
0 mg / m ² TEGO WET 265 ^™ and 5.0
mg / m ² of TEGO GLIDE 410 ^™ .

EPI-REZ 3510 W-60 is S
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at hold Chemicals. EUREDUR 115 is Witco GmbH
Is a commercially available polyamideamino.

Example 5 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
25.8 mg / m ² of EPI-REZ 3510 W-
JEFFAMINE E at 60 ^™ , 29.2 mg / m ²
D900 ^™ , 11.5 mg / m ² nitrocellulose,
2.1 mg / m ² SOLSPERSE 5000 ^™ ,
SOLSPERSE 28000 at 11.3 mg / m ^2
TM , 2.0 mg / m ² of TEGO WET265 ^™ and 5.0 mg / m ² of TEGO GLIDE 410 ^™ .

EPI-REZ 3510 W-60 is S
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at hold Chemicals. JEFFAMINE ED900 is Huntsm
A commercially available polyether diamine based on a polyethylene oxide backbone which is commercially available from An Corporation, Houston.

Example 6 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in a 50/50 ratio of methyl ethyl ketone / methoxypropanol at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
22.7 mg / m ² of EPI-REZ 6006 W-
70 ^™ , 32.3 mg / m ² TB 3354H ^™ , 1
1.5 mg / m ² nitrocellulose, 2.1 mg / m ²
SOLSPERSE 5000 ^™ , 11.3 mg / m
² SOLSPERSE 28000 ^™ , 2.0 mg /
TEGO of m ² WET 265 ^TM and 5.0 mg / m ²
Of TEGO GLIDE 410 ^™ .

EPI-REZ 6006 W-70 is S
It is an epoxidized o-cresol novolak resin that is commercially available at hold Chemicals. TB 3354H is an amine hardener for water-soluble epoxides commercially available at Witco GmbH.

Example 7 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
32.2 mg / m ² of EPI-REZ 5520 W-
60 ^™ , 22.8 mg / m ² TB 3354H ^™ , 1
1.5 mg / m ² nitrocellulose, 2.1 mg / m ²
SOLSPERSE 5000 ^™ , 11.3 mg / m
² SOLSPERSE 28000 ^™ , 2.0 mg /
TEGO of m ² WET 265 ^TM and 5.0 mg / m ²
Of TEGO GLIDE 410 ^™ .

EPI-REZ 5520 W-60 is S
A urethane-modified epoxy resin commercially available at hold Chemicals. TB 3354
H is an amine hardener for water-soluble epoxides commercially available at Witco GmbH.

Example 8 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
6.5 mg / m ² of EPI-REZ 3510 W-6
0 ^™ , 48.5 mg / m ² of JEFFAMINE M3
003 ^™ , 11.5 mg / m ² nitrocellulose,
2.1 mg / m ² SOLSPERSE 5000 ^™ ,
SOLSPERSE 28000 at 11.3 mg / m ^2
™ , 2.0 mg / m ² TEGO WET 265 ^™ and 5.0 mg / m ² TEGO GLIDE 410 ^™
Was contained.

EPI-REZ 3510 W-60 is S
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at hold Chemicals. JEFFAMINE M3003 is Huntsm
8/49 propylene oxide / commercially available from An Corporation, Houston
Monoamine having an ethylene oxide ratio and a molecular weight of about 3000.

Example 9 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
37.2 mg / m ² of EPI-REZ 3510 W-
60 ^™ , 17.8 mg / m ² of EPI-CURE 31
1. 40 ^™ , 11.5 mg / m ² nitrocellulose,
1 mg / m ² SOLSPERSE 5000 ^™ , 1
1.3 mg / m ² SOLSPERSE 2800
0 ^TM , 2.0 mg / m ² TEGO WET 265 ^TM
And 5.0 mg / m ² of TEGO GIDE 410
^TM was included.

EPI-REZ 3510 W-60 is S
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at hold Chemicals. EPI-CURE 3140 is also Shell
A low viscosity polyamide commercially available from Chemicals.

Example 10 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
EPI-REZ 3510 W- at 52.4 mg / m ²
60 ^TM, poly (ethyleneimine) of 2.6 mg / m ² substituents trimethoxysilylpropyl, nitrocellulose 11.5 mg / m ^2, of 2.1mg / m ² SOLSPER
SE 5000 ^™ , 11.3 mg / m ² SOLSPE
RSE 28000 ^™ , 2.0 mg / m ² TEGO
WET 265 ^TM and 5.0 mg / m ² TEGO G
Contains LIDE 410 ^™ .

EPI-REZ 3510 W-60 is S
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at hold Chemicals. Poly (ethylene imine) -substituted trimethoxysilylpropyl is commercially available at ABCR.

Example 11 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
31.4 mg / m ² of EPI-REZ 3510 W-
JEFFAMINE T at 60 ^™ , 23.6 mg / m ²
403 ^™ , 11.5 mg / m ² nitrocellulose,
2.1 mg / m ² SOLSPERSE 5000 ^™ ,
SOLSPERSE 28000 at 11.3 mg / m ^2
™ , 2.0 mg / m ² TEGO WET 265 ^™ and 5.0 mg / m ² TEGO GLIDE 410 ^™
Was contained.

EPI-REZ 3510 W-60 is S
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at hold Chemicals. JEFFAMINE T403 is Witco G
Trifunctional propylene oxide amine commercially available at mbH.

Example 12 The same base as described in Comparative Example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

On this layer was coated an IR-sensitive layer from a 1.2345% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
95.2 mg / m ² of EPI-REZ 3510 W-
60 ^™ , 4.8 mg / m ² of 2-methylimidazole,
11.5 mg / m ² nitrocellulose, 2.1 mg / m ²
SOLSPERSE of m ² 5000 ^TM, 11.3mg
/ M ² SOLSPERSE 28000 ^™ , 2.0 m
g / m ² TEGO WET 265 ^™ and 5.0 mg
/ M ² of TEGO GLIDE 410 ^™ .

EPI-REZ 3510 W-60 is S
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at hold Chemicals. Aldrich as 2-methylimidazole
A 99% rating, commercially available at Chemie, was used.

Example 13 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
22.9 mg / m ² of EPI-REZ 3510 W-
EUREDUR 115 at 60 ^™ , 27.5 mg / m ^2
TM , 4.6 mg / m ² of 3-aminopropyltriethoxysilane, 11.5 mg / m ² of nitrocellulose,
2.1 mg / m ² SOLSPERSE 5000 ^™ ,
SOLSPERSE 28000 at 11.3 mg / m ^2
™ , 2.0 mg / m ² TEGO WET 265 ^™ and 5.0 mg / m ² TEGO GLIDE 410 ^™
Was contained. For the preparation of the coating solution, it is very important to first add 3-aminopropyltriethoxysilane to the dispersion before adding the epoxy resin or hardener.

EPI-REZ 3510 W-60 is S
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at hold Chemicals. EUREDUR 115 is Witco GmbH
Is a commercially available polyamideamino.
Ald as 3-aminopropyltriethoxysilane
9 from rich Chemie Steinheim
An 8% purity grade was used.

Example 14 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
EUROPOX 7001/75 at 36.2 mg / m ²
W ^™ , 9.4 mg / m ² EUREDUR 115 ^™ ,
9.4 mg / m ² of 3- (2-aminoethylamino)-
Trimethoxysilane, nitrocellulose 11.5 mg / m ^2, of 2.1mg / m ² SOLSPERS
E 5000 ^™ , 11.3 mg / m ² SOLSPER
SE 28000 ^TM , 2.0 mg / m ² TEGO W
ET 265 ^{T M} and TEGO GL of 5.0mg / m ²
Contains IDE 410 ^™ .

For the preparation of the coating solution, it is very important to first add 3- (2-aminoethylamino) -propyltrimethoxysilane to the dispersion before adding the epoxy resin or hardener. .

[0130] EUREPOX 7001 / 75W is Wi
Bisphenol A-epoxy resin commercially available from tco GmbH. EUREDUR 115
Is a polyamidoamino commercially available at Witco GmbH. ShinE as 3- (2-aminoethylamino) -propyltrimethoxysilane
KB from tsu Chemicals Co, Ltd
M-603 was used.

Example 15 The same base as described in Comparative Example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 1.0095% by weight solution in methyl ethyl ketone / methoxypropanol in a 50/50 ratio at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer is 115 mg / m ² carbon black,
EUROPOX 7001/75 at 36.2 mg / m ²
W ^™ , 9.4 mg / m ² EUREDUR 115 ^™ ,
9.4 mg / m ² DYNASILAN AMMO ^™ ,
11.5 mg / m ² nitrocellulose, 2.1 mg / m ²
SOLSPERSE of m ² 5000 ^TM, 11.3mg
/ M ² SOLSPERSE 28000 ^™ , 2.0 m
g / m ² TEGO WET 265 ^™ and 5.0 mg
/ M ² of TEGO GLIDE 410 ^™ .

To prepare the coating solution, first add DYNASI before adding the epoxy resin or hardener.
LAN AMMO: It is very important to add 3-aminopropyltrimethoxysilane to the dispersion.

EUREPOX 7001 / 75W is Wi
Bisphenol A-epoxy resin commercially available from tco GmbH. EUREDUR 115
Is a polyamidoamino commercially available at Witco GmbH. DYNASILAN AMMO
Is a product of Huels AG.

Example 16 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 50/50 ratio of a 0.4220% by weight solution in methyl ethyl ketone / methoxypropanol at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer contains 35 mg / m ² of IR-absorber ST7
98 ^™ : 2- (2- (2-chloro-3- (2-dihydro-1,1,3-trimethyl-2H-benzo (e) indole-2-ylidene) -ethylidene) -1-cyclohexene-1- Yl) -ethenyl) -1,1,3-trimethyl-1H-benzo (e) indolium 4-methylbenzenesulfonate, 12.4 mg / m ² FLEXO-B
LAU 630 ^™ , 13.8 mg / m ² EPI-RE
Z 3510 E-60 ^™ , TB at 16.2 mg / m ²
3354H ^™ , 2.0mg / m ² TEGO WET
265 ^TM and 5.0 mg / m ² TEGO GLID
E410 ^TM was included.

ST798 is Synthon Wolfe
n Commercially available from Germany, F
LEXO-BLAU 630 is from BASF, Ludwig
It is commercially available from Shafen, Germany. EPI-REZ 3510 W-60 is She
An aqueous dispersion of a liquid bisphenol A epoxy resin commercially available at 11 Chemicals. TB 3354H is an amine hardener for water-soluble epoxides commercially available at Witco GmbH.

Example 17 The same base as described in comparative example 1 was used. Preparation of Heat Mode Imaging Element The lithographic base described in Example 1 was first coated with a layer from a 8.6% by weight solution in tetrahydrofuran / methoxypropanol in a 55/45 ratio at a wet coating thickness of 14 μm. . The resulting layer is 88% AL
NOVOL SPN452 ^™ and 12% 3,4,5-
Trimethoxybenzoic acid was included.

An IR-sensitive layer was coated on this layer from a 50/50 ratio of a 0.4220% by weight solution in methyl ethyl ketone / methoxypropanol at a wet coating thickness of 20 μm. Make this layer at least 12
Dry at a temperature of 0 ° C. for at least 40 seconds. I obtained
The R-sensitive layer contains 35 mg / m ² of IR-absorber ST7
98 ^™ : 2- (2- (2-chloro-3- (2-dihydro-1,1,3-trimethyl-2H-benzo (e) indole-2-ylidene) -ethylidene) -1-cyclohexene-1- Yl) -ethenyl) -1,1,3-trimethyl-1H-benzo (e) indolium 4-methylbenzenesulfonate, 12.4 mg / m ² FLEXO-B
LAU 630 ^™ , 22.7 mg / m ² EUREPO
X 7001 / 75W ^™ , 3.6 mg / m ² EURE
DUR 115 ^™ , 3.6 mg / m ² of 3-aminopropyltriethoxysilane, 2.0 mg / m ² of TEGO
WET 265 ^TM and 5.0 mg / m ² TEGO
GLIDE 410 ^™ was included.

ST798 is Synthon Wolfe
n Commercially available from Germany, F
LEXO-BLAU 630 is from BASF, Ludwig
It is commercially available from Shafen, Germany. EUREPOX 7001 / 75W is Witc
o Bisphenol A-epoxy resin commercially available from GmbH. EUREDUR 115 is W
Polyamideamino commercially available at itco GmbH. Aldrich Chemie Stein as 3-aminopropyltriethoxysilane
A 98% purity grade from Heim was used. Heat Mode Imaging Element Scratch The above materials in Comparative Example 1 and Examples 2-17 were scratched in a standard test. In this test,
The scratch is formed by moving the needle at a speed of 96 cm / min under a well-defined load. Needle is 1.5
It is a Robin type having a radius of mm. Form 15 scratches under the following load: 57-85-11
4-142-170-113-169-225-282
-338-400-600-800-1000 and 12
00mN.

After the formation of 15 scratches, the material is exposed. Exposure of Heat Mode Imaging Element All of the above materials were replaced with a Creo 3244 TTM external drum plate setter.
plateletter) and 263 mJ / cm ²
And 2400 dpi. Development of the Imagewise Exposed Element After exposure of the manufactured imaging element, the element was developed in an aqueous alkaline developer. These developments are OZASOL
EP262A ^TM (OZASOL EP262A is Ag
(commercially available from Fa.) and a Technigraph NPX-32 processor filled with water for the rinse section and OZASOL RC795 ^™ rubber for the rubberization section at 25 ° C. at a speed of 1 m / min. Testing for chemical resistance Place 40 μl drops of a 30% solution of the iso-propanol / water mixture on the image and screen surfaces. After 10 minutes, the drops are removed using a cotton pad. This is repeated with a 40 and 50% mixture of iso-propanol in water. Evaluation of the lithographic quality of the material The plates are printed on a Heidelberg GTO46 printing press using regular inks (K + E) and dampening fluid (Rotamatic). The prints are evaluated for scum formation in the IR-exposed areas and excellent ink absorption in the non-imaging areas. Evaluation of scratch resistance on prints Fifteen scratches are checked for width of damage and give the corresponding quotations as shown in Table 1.

[0142]

[Table 1] The sum of all the scores given indicates the resulting scratch resistance of the material. The lower the value, the better the scratch resistance. Evaluation of chemical resistance Six places where drops were placed on the prints are visually inspected for image damage. Score 0 without attack. A score of 4 is given for the total loss of the image. All six scores are summed to give a figure for chemical resistance. This gives a value of 0-24. Higher values mean lower chemical resistance. result

[0143]

[Table 2] OK print quality: means no visible scum formation in non-image areas and excellent ink absorption.

From the results in Table 2, it can be seen that all of the inventive examples have better scratch resistance than the comparative examples and that the inventive examples containing carbon black as IR-absorber correspond to the corresponding comparative examples. It is clear that it has better chemical resistance than the examples. The main features and aspects of the present invention are as follows.

1. A first layer containing a polymer soluble in aqueous alkaline solution on a lithographic base having a hydrophilic surface and an uppermost layer on the same side of the lithographic base as the first layer that is IR-sensitive and impermeable to an alkaline developer Wherein the first layer and the top layer are heat mode imaging elements for making a lithographic printing plate wherein the top layer can be one and the same layer;
A heat mode imaging element comprising at least one compound in an amount of 500 mg / m < ² > and a hardener.

[0146] 2. 2. The heat mode imaging element of claim 1 wherein said compound containing an epoxy unit is a condensation product of epichlorohydrin and bisphenol A.

[0147] 3. 2. The heat mode imaging element of claim 1, wherein said compound containing an epoxy unit is a compound selected from the group consisting of an epoxidized o-cresol novolak resin and a urethane modified epoxy resin.

4. 2. The heat mode imaging element of claim 1 wherein said top layer comprises a low viscosity amine as a hardener.

5. 2. The heat mode imaging element of claim 1 wherein said top layer comprises a compound selected from the group consisting of polyaminoamides and polyamides as a hardener.

6. 2. The heat mode imaging element according to claim 1, wherein said uppermost layer comprises a compound selected from the group consisting of monoamine polyoxyalkyleneamine, diamine polyoxyalkyleneamine and triamine polyoxyalkyleneamine as a hardener.

7. 2. The heat mode imaging element of claim 1 wherein said top layer comprises trimethylsilane modified polyethylene imine as a hardener.

8. 2. The heat mode imaging element of claim 1 wherein said top layer comprises 2-methylimidazole as a hardener.

9. The heat mode imaging element of claim 1 wherein said top layer comprises an aminoalkyl trialkoxysilane as a coupling agent.

10. a) exposing the heat mode imaging element according to any of the above items 1 to 9 image-wise to IR-radiation; b) exposing the image mode exposed heat mode imaging element using an aqueous alkaline developer. Producing a lithographic printing plate comprising dissolving the exposed areas of the first and top layers, which can be the same, and leaving the unexposed areas of the first layer undissolved. Method.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Houb van Aelt Belgium B2640 Malt Cell Septes Trat 27 Agfa-Gevuert na Mulose Fuennotsyajp (72) Inventor Giyoan Vermeersch Belgium Bee 2640 Maltcell Septes Trat 27 Aghu-Gevert na Mlose Fennaught Jap (72) Inventor Marc van Dame Belgium B2640 Maltcell Septes Trat 27 Agfah-Gevelt Nemrose Fennaught Inside the shop (72) Inventor Guido Hoquier Belgium 2640 Malt cell Septes Trat 27 Agfa-Gevert na Mrose Fenno In Shiyatsupu

Claims (2)

[Claims] 1. A lithographic base having a hydrophilic surface, a first layer containing a polymer soluble in an aqueous alkaline solution and an IR-sensitive and non-permeable with respect to an alkaline developer on the same side as the first layer of the lithographic base. Comprising a certain top layer,
A heat mode imaging element for making a lithographic printing plate wherein the first layer and the top layer can be one and the same layer; the top layer containing 20-50 epoxy units.
A heat mode imaging element comprising at least one compound in an amount of 0 mg / m ² and a hardener. 2. a) exposing the heat mode imaging element of claim 1 image-wise to IR-rays; b) exposing the image-wise exposed heat mode imaging element to an aqueous alkaline developer. Lithographic printing plate comprising the steps of: dissolving the exposed areas of the first and top layers, which can be the same, and leaving the unexposed areas of the first layer undissolved. Method.