JP2006503340A - Thermosensitive lithographic printing plate precursor - Google Patents

Abstract

A thermosensitive lithographic printing plate precursor comprising a hydrophilic support and an oleophilic coating comprising an infrared absorber and a polymer, wherein the polymer has a phenyl group of phenolic monomer units having a structure- A phenolic monomer unit substituted by a group having N = NQ, wherein the -N = N- group is covalently bonded to the carbon atom of the phenyl group and Q is an aromatic group A thermosensitive lithographic printing plate precursor is disclosed in which the polymer comprises and the substitution enhances the chemical resistance of the coating.

Description

  The present invention relates to a heat-sensitive lithographic printing plate precursor.

  A lithographic printing machine uses a so-called printing master, for example a printing plate, installed on a cylinder of the printing machine. The master carries a lithographic image on its surface and a print is obtained by applying ink to the image and then transferring the ink from the master onto a receiving material, typically paper. In conventional so-called “wet” lithographic printing, the ink and fountain solution (also referred to as fountain solution) are oleophilic (or hydrophobic, ie ink-receptive, water-repellent) areas and hydrophilic (or oleophobic, That is, it is supplied to a lithographic image comprising water-receptive and ink-repellent areas. In so-called driographic printing, the lithographic image consists of ink-accepting and ink-abhesive (ink-repelling) areas and only ink is supplied to the master during driographic printing.

  The print master is generally obtained by the so-called computer-to-film method, in which various preprinting stages such as typeface selection, scanning, color separation, screening, trapping, layout and assembly are digital. And each color selection is transferred to the platemaking film using an image-setter. After processing, the film can be used as an exposure mask for the imaging material, referred to as a plate precursor, and a printing plate is obtained that can be used as a master after plate processing.

  Typical printing plate precursors for computer-to-film processes are hydrophilic supports and photosensitive polymers including UV-sensitive diazo compounds, dichromate-sensitized hydrophilic colloids and a variety of synthetic photopolymers. It comprises an image recording layer. In particular, diazo-sensitized systems are widely used. With image-wise exposure, typically a film mask in an ultraviolet contact frame, the exposed image areas become insoluble and the unexposed areas remain soluble in the aqueous alkaline developer. The plate is then treated with a developer to remove the diazonium salt or diazo resin in the unexposed areas. Thus, the exposed area defines the image area (printing area) of the print master, and such a printing plate precursor is therefore referred to as “negative working”. Also known are positive working materials in which the exposed areas define non-printing areas, for example plates with a novolak / naphthoquinone-diazide coating that dissolves in the developer only in the exposed areas.

  In addition to the photosensitive materials described above, thermosensitive printing plate precursors have become very popular. Such thermal materials offer the advantage of daylight stability and are particularly used in so-called computer-to-plate methods in which the plate precursor is exposed directly, i.e. without using a film mask. Is done. The material is exposed to heat or infrared and the generated heat is (physical) chemical processes such as ablation, polymerization, insolubilization by polymer cross-linking, heat-induced solubilization, degradation, or thermoplasticity Causes particle aggregation of polymer latex.

  Known thermosensitive printing plate precursors typically have a hydrophilic support and a parent that is alkali-soluble in the exposed areas (positive working material) or in the unexposed areas (negative working material). A coating comprising an oily polymer and an infrared absorbing compound. Such lipophilic polymers are typically phenolic resins.

  In US Pat. No. 6,057,059, a coating composition comprises a polymeric material having functional groups that have the property that the functionalized polymeric material insolubilizes the developer prior to transmission of radiation and then solubilizes the developer. A method for producing a positive acting resistance pattern on a substrate is described. Suitable functional groups are known to be prone to hydrogen bonding and can comprise amino, amido, chloro, fluoro, carbonyl, sulfinyl and sulfonyl groups, and these groups can be combined with phenolic hydroxy groups. It is combined with the polymer substance by an esterification reaction to form a resin ester.

  Patent Document 2 discloses a lithographic printing plate in which the composition contains an alkali-soluble resin having a phenolic hydroxyl group and at least a part of the phenolic hydroxyl group is esterified with a sulfonic acid or a carboxylic acid compound. A photosensitive composition is described.

  Patent Document 3 describes an image forming material comprising a recording layer composed of a composition whose solubility in water or an aqueous alkali solution varies under the influence of light or heat. This recording layer comprises a vinylphenol polymer or a phenolic polymer, in which the hydroxy group and the alkoxy group are directly bonded to the aromatic hydrocarbon ring. Alkoxy groups contain 20 or fewer carbon atoms.

  Patent Document 4 discloses a photosensitive positive working printing plate comprising an azo dye which is a novolak resin carrying a diazophenyl chromophore moiety on a phenol ring and undergoes a color change in the presence of a photolysis product of a diazonium salt. Is described. This discoloration is caused by protonation of the azo-dye nitrogen with an acid produced by a diazonium salt during exposure. This azo-dye is used as an indicator dye that makes it possible to inspect areas of the plate that have received light. Compared to conventional indicator dyes, this azo-dye has increased solubility in the developer solution and therefore does not remain on the plate after development. As a result, there is no risk of residual dye that can cause contamination or smearing on non-image areas during the printing process. The most preferred azo-dye as an indicator dye in these photosensitive compositions capable of undergoing such intense discoloration in the visible light range due to protonation is derived from azo coupling of diphenylamine-4-diazonium fluoroborate with novolak. Azo-dyes.

The ink and fountain solution supplied to the plate during the printing process can attack the coating, and as a result, the resistance of the coating to these liquids, referred to below as “chemical resistance,” affects the number of prints. Can be given. The most widely used polymers in these coatings are phenolic resins, and in the prior art described above, the number of times printed by modifying such resins by chemical substitution reactions on the hydroxyl groups of the phenolic groups. It has been found that can be improved. However, this modification reaction reduces the number of free hydroxyl groups on the polymer and thereby reduces the solubility of the coating in the alkaline developer. The modification reaction provided by the present invention can increase the chemical resistance of the coating without substantially reducing the developing ability of the coating.
WO99 / 01795 pamphlet European Patent Application No. 0934822 European Patent Application No. 1072432 US Pat. No. 3,929,488

  It is an aspect of the present invention to provide a heat-sensitive lithographic printing plate precursor comprising a heat-sensitive coating having improved chemical resistance of the coating to printing fluids and printing chemicals. The purpose is that the phenyl group of the phenolic monomer unit has the structure -N = N-Q, wherein the -N = N- group is covalently bonded to the carbon atom of the phenyl group and Q is an aromatic group. Realized by a precursor as defined in claim 1 characterized in that the precursor heat-sensitive coating comprises a polymer comprising a phenolic monomer unit substituted by a group having .

Specific embodiments of the invention are defined in the dependent claims.
Detailed Description of the Invention In order to obtain heat-sensitive lithographic printing plates with improved printing times, cleaning liquids for printing liquids such as fountain solutions and inks and for example for plates, blankets and press rollers It is important to increase the chemical resistance of heat sensitive coatings to printing press chemicals such as These printing properties are influenced by the composition of the coating, where the polymer type is one of the most important factors with respect to this property.

  According to the present invention, a heat-sensitive lithographic printing plate precursor comprising a support having a hydrophilic surface and an oleophilic coating, wherein the coating comprises an infrared absorber and a phenyl group of phenolic monomer units By a group having the structure —N═NQ, also referred to as “azo-aryl group”, wherein the —N═N— group is covalently bonded to the carbon atom of the phenyl group and Q is an aromatic group. There is provided a thermosensitive lithographic printing plate precursor comprising a polymer comprising a substituted phenolic monomer unit.

  The lipophilic coating comprising this polymer has the structure —N═NQ, where the —N═N— group is covalently bonded to the carbon atom of the phenyl group and Q is an aromatic group. It is also an aspect of the present invention to have increased chemical resistance by modification of the polymer with this particular substituent having: This chemical resistance can be measured by several tests.

  A suitable method for quantifying chemical resistance is described as test 4 in the Examples. Preferred precursors according to the present invention are less than 45%, more preferably less than 35% and most preferably less than 20% coating weight loss, calculated as described in the referenced Test 4. Is characterized by

  According to the invention, the substituent Q of the polymer comprising a phenolic monomer substituted as described above is at least one heteroatom selected from nitrogen, oxygen or sulfur, preferably a nitrogen or sulfur atom. Is an aromatic group which may comprise The heteroatom may be part of an aromatic ring and / or may be present in a substituent attached to the ring.

According to the present invention, the substituent Q can have the structure -A- (T) _n . In this structure, A represents a monocyclic 5- or 6-membered aromatic group or a 5- or 6-membered aromatic ring fused with another ring system. Fused means that the two ring systems have two adjacent carbon atoms in common. In this structure, n is an integer selected between 0 and the maximum available position on the aromatic group A, and each T group is —SO ₂ —NH—R ¹ , —NH—SO ₂ —R. ⁴ , —CO—NR ¹ —R ² , —NR ¹ —CO—R ⁴ , —NR ¹ —CO—NR ² —R ³ , —NR ¹ —CS—NR ² —R ³ , —NR ¹ —CO— O—R ¹ , —O—CO—NR ¹ —R ² , —O—CO—R ⁴ , —CO—O—R ² , —CO—R ³ , —SO ₃ —R ¹ , —O—SO ₂ —R ⁴ , —SO ₂ —R ¹ , —SO—R ⁴ , —P (═O) (— O—R ¹ ) (— O—R ² ), —O—P (═O) (— O— ^{R 1) (- O-R} 2), - NR 1 -R 2, -O-R 2, -S-R 2, -N = NR 4, -CN, -NO 2, halogenide or -M- It is selected from R ¹ , M represents a divalent linking group having 1 to 8 carbon atoms,
R ¹ , R ² and R ³ are each independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁴ and R ⁵ are selected from optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
Or at least 2 group selected from each R < ¹ > -R < ⁵ > represents the atom required in order to form a cyclic structure together.

  According to the present invention, the substituent —N═NQ is represented by the formula

[Wherein X is CR ³ , NR ⁴ or N, Y is an atom necessary to form a 5- or 6-membered aromatic ring, and the atom is CR ³ , NR ⁴ , N, Selected from the group consisting of S or O;
Each R ¹ , R ² and R ³ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ⁵ , —NH—SO ₂ —R ⁷ , —CO—NR ⁵ —R ⁶ , —NR ⁵ —CO—R ⁷ , —O—CO—R ⁷ , —CO—O—R ⁵ , —CO—R ⁵ , —SO ₃ —R ⁵ , —SO ₂ —R ⁵ , —SO ₂ —R ⁷ , —P (═O) (— O—R ⁵ ) (— O—R ⁶ ), —NR ⁵ —R ⁶ , Selected from —O—R ⁵ , —S—R ⁵ , —CN, —NO ₂ , halogen or —M—R ⁵ , wherein M represents a divalent linking group having 1 to 8 carbon atoms;
R ⁴ , R ⁵ and R ⁶ are independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁷ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁷ together represent the atoms necessary to form a cyclic structure]
Can comprise.

  According to the present invention, the substituent —N═NQ is represented by the formula

[Wherein Z ¹ and Z ² are independently selected from CR ¹ or N;
R ¹ is selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
n is 0, 1, 2, 3 or 4; m is 0, 1, 2 or 3;
R ² and R ³ are hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ⁴ , —NH —SO ₂ —R ⁶ , —CO—NR ⁴ —R ⁵ , —NR ⁴ —CO—R ⁶ , —O—CO—R ⁶ , —CO—O—R ⁴ , —CO—R ⁴ , —SO ₃ —R ⁴ , —SO ₂ —R ⁴ , —SO—R ⁶ , —P (═O) (— O—R ⁴ ) (— O—R ⁵ ), —NR ⁴ —R ⁵ , —O—R ⁴ , —S—R ⁴ , —CN, —NO ₂ , halogen or —M—R ⁴ , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ⁴ and R ⁵ are independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁶ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁶ together represent the atoms necessary to form a cyclic structure]
Can comprise.

  According to the present invention, the substituent —N═NQ is represented by the formula

[Wherein n is 0, 1, 2, 3, 4 or 5;
Each R ¹ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ² , —NH—SO _{^{2 -R 4, -CO-NR 2}} -R 3, -NR 2 -CO-R 4, -O-CO-R 4, -CO-O-R 2, -CO-R 2, -SO 3 -R ² , —SO ₂ —R ² , —SO—R ⁴ , —P (═O) (— O—R ² ) (— O—R ³ ), —NR ² —R ³ , —O—R ² , — Selected from S—R ² , —CN, —NO ₂ , halogen or —M—R ² , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ² and R ³ are independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁴ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁴ together represent the atoms necessary to form a cyclic structure]
Can comprise.

  According to the present invention, the substituent —N═NQ is represented by the formula

[Wherein n is 0, 1, 2, 3 or 4;
Each R ¹ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ² , —NH—SO _{^{2 -R 4, -CO-NR 2}} -R 3, -NR 2 -CO-R 4, -O-CO-R 4, -CO-O-R 2, -CO-R 2, -SO 3 -R ² , —SO ₂ —R ² , —SO—R ⁴ , —P (═O) (— O—R ² ) (— O—R ³ ), —NR ² —R ³ , —O—R ² , — Selected from S—R ² , —CN, —NO ₂ , halogen or —M—R ² , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
X is O, S or NR ⁵ ;
R ² , R ³ and R ⁵ are independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁴ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁵ together represent the atoms necessary to form a cyclic structure]
Can comprise.

  According to the present invention, the substituent —N═NQ is represented by the formula

[Wherein n is 0, 1, 2 or 3;
Each R ¹ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ² , —NH—SO _{^{2 -R 4, -CO-NR 2}} -R 3, -NR 2 -CO-R 4, -O-CO-R 4, -CO-O-R 2, -CO-R 2, -SO 3 -R ² , —SO ₂ —R ² , —SO—R ⁴ , —P (═O) (— O—R ² ) (— O—R ³ ), —NR ² —R ³ , —O—R ² , — Selected from S—R ² , —CN, —NO ₂ , halogen or —M—R ² , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ² , R ³ , R ⁵ and R ⁶ are independently selected from hydrogen or an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group ,
R ⁴ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Alternatively, at least two groups selected from each R ^{1 to} R ⁴ together represent the atoms necessary to form a cyclic structure,
Or R ⁵ and R ⁶ together represent the atoms necessary to form a cyclic structure]
Can comprise.

  According to the present invention, the substituent —N═NQ is represented by the formula

[Wherein n is 0, 1, 2 or 3; m is 0, 1, 2, 3 or 4;
Each R ¹ and R ² is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ³ , — NH—SO ₂ —R ⁵ , —CO—NR ³ —R ⁴ , —NR ³ —CO—R ⁵ , —O—CO—R ⁵ , —CO—O—R ³ , —CO—R ³ , —SO _3- R ³ , —SO ₂ —R ³ , —SO—R ⁵ , —P (═O) (— O—R ³ ) (— O—R ⁴ ), —NR ³ —R ⁴ , —O—R ³ , —S—R ³ , —CN, —NO ₂ , halogen or —M—R ³ , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ³ and R ⁴ are independently selected from hydrogen or an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
R ⁵ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁵ together represent the atoms necessary to form a cyclic structure]
Can comprise.

  According to the present invention, the substituent —N═NQ is represented by the formula

[Wherein n is 0, 1, 2 or 3;
Each R ¹ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ² , —NH—SO _{^{2 -R 4, -CO-NR 2}} -R 3, -NR 2 -CO-R 4, -O-CO-R 4, -CO-O-R 2, -CO-R 2, -SO 3 -R ² , —SO ₂ —R ² , —SO—R ⁴ , —P (═O) (— O—R ² ) (— O—R ³ ), —NR ² —R ³ , —O—R ² , — Selected from S—R ² , —CN, —NO ₂ , halogen or —M—R ² , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ² , R ³ , R ⁵ and R ⁶ are independently selected from hydrogen or an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group ,
R ⁴ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁶ together represent the atoms necessary to form a cyclic structure]
Can comprise.

  The polymers of the present invention can be reacted by several means, for example by reacting a polymer containing phenolic monomer units with a diazonium salt or by reacting a phenolic monomer with a diazonium salt and thereafter. It can be obtained by polymerizing or polycondensing the monomer obtained. These pre-modified monomers can preferably be copolymerized or copolycondensed with other monomers.

  Reaction of a diazonium salt with a phenol group under alkaline conditions results in the coupling of a diazo-group on the aromatic ring structure, which is represented schematically as shown in the general formula:

[Wherein Q represents an aromatic group and R is a hydrogen atom or a substituent such as an alkyl group].

A diazonium salt for the purposes of this application is obtained from diazotization of the corresponding aromatic amine in the presence of an acid such as HCl, H ₂ SO ₄ or H ₃ PO ₄ followed by a diazotization reagent such as nitrite. Can be induced by. Most of the diazonium salts are relatively stable at low temperatures such as from about 0 ° C. to about 5 ° C. and they are soluble in water or in mixtures of water and organic solvents such as acetic acid or 1-methoxy-2-propanol. It is. The solution of diazonium salt can be used for further reaction with a solution of a polymer containing phenol groups. This azo-coupling reaction replaces the aromatic diazo group on the aromatic ring structure of the phenol group. This azo coupling is at the ortho- or para-position of the hydroxyl group, and the availability of these positions for such coupling reactions, for example the position where the polycondensation reaction of phenolic monomer compounds and formaldehyde has occurred. Can get up.

  Examples of aromatic amines that can be diazotized to diazonium salts that can be further used in azo-coupling with phenol groups are:

  The polymer containing phenolic monomer units can be a random, alternating, block or graft copolymer of different monomers and, for example, a vinylphenol polymer or copolymer, a novolac resin or a resole resin You can choose from. A novolac resin is preferred.

  Novolac resins or resole resins are aromatic hydrocarbons such as phenol, o-cresol, p-cresol, m-cresol, 2,5-xylenol, 3,5-xylenol, resorcinol, pyrogallol in the presence of an acid catalyst. At least one member selected from bisphenol, bisphenol A, trisphenol, o-ethylphenol, p-ethylphenol, propylphenol, n-butylphenol, t-butylphenol, 1-naphthol and 2-naphthol, and aldehydes such as A small amount selected from formaldehyde, glyoxal, acetaldehyde, propionaldehyde, benzaldehyde and furfural and ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone. Both the polycondensation of one aldehyde or ketone can be produced. Instead of formaldehyde and acetaldehyde, paraformaldehyde and paraaldehyde can be used, respectively.

  The weight average molecular weight of the novolak resin, measured by gel permeation chromatography using general calibration and polystyrene standards, is preferably 500-150,000 g / mol, more preferably 1,500-15,000 g / mol.

The poly (vinylphenol) resin may be a polymer of one or more hydroxy-phenyl containing monomers, such as hydroxystyrene or hydroxy-phenyl (meth) acrylate. Examples of such hydroxystyrenes are o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2- (o-hydroxyphenyl) propylene, 2- (m-hydroxyphenyl) propylene and 2- (p-hydroxy). Phenyl) propylene. Such hydroxystyrenes may have substituents on the aromatic ring such as chlorine, bromine, iodine, fluorine or C _1-4 alkyl groups. An example of such a hydroxy-phenyl (meth) acrylate is 2-hydroxy-phenyl methacrylate.

  Poly (vinylphenol) resins can generally be produced by polymerizing one or more hydroxy-phenyl containing monomers in the presence of a radical initiator or a cationic polymerization initiator. Poly (vinylphenol) resin may be one or more of these hydroxy-phenyl-containing monomers and other monomeric compounds, such as acrylate monomers, methacrylate monomers, acrylamide monomers It can also be produced by copolymerization with a methacrylamide monomer, a vinyl monomer, an aromatic vinyl monomer or a diene monomer.

  The weight average molecular weight of the poly (vinylphenol) resin, measured by gel permeation chromatography using general calibration and polystyrene standards, is preferably 1,000 to 200,000 g / mol, more preferably 1,500 to 50,000 g / mol. Is a mole.

Examples of polymers containing phenolic monomer units that can be modified with diazonium salts are:
POL-01: ALNOVOL SPN452 is a 40 wt% solution of novolak resin in Dowanol PM obtained from CLARIANT GmbH.
Dawanol PM consists of 1-methoxy-2-propanol (> 99.5%) and 2-methoxy-1-propanol (<0.5%).
POL-02: Arnobol SPN400 is a 44 wt% solution of novolak resin in Dawanol PMA obtained from Clariant GmbH.
Dawanol PMA consists of 2-methoxy-1-methyl-ethylacetate.
POL-03: Arnobol HPN100 is a novolak resin obtained from Clariant GmbH.
POL-04: DUrite PD443 is a novolak resin obtained from BORDEN CHEM. INC.
POL-05: Julite SD423A is a novolak resin obtained from Bolden Hem, Inc.
POL-06: Julite SD126A is a novolak resin obtained from Bolden Hem, Inc.
POL-07: BAKELITE 6866LB02 is a novolac resin obtained from BAKELITE AG.
POL-08: Bakelite 6866LB03 is a novolak resin obtained from Bakelite AG.
POL-09: KR400 / 8 is a novolak resin obtained from KOYO CHEMICALS INC.
POL-10: HRJ1085 is a novolak resin obtained from SCHECTADY INTERNATIONAL INC.
POL-11: HRJ 2606 is a phenol novolac resin obtained from Schnektadee International, Inc.
POL-12: LYNCUR CMM is a copolymer of 4-hydroxy-styrene and methyl methacrylate obtained from SIBER HEGNER.

  The polymers of the present invention can contain more than one type of azo-aryl group. In this situation, each type of azo-aryl group can be introduced continuously, or a mixture of different diazonium salts can be reacted on the polymer. The preferred amount of each type of azo-aryl group introduced into the polymer is between 0.5 mol% and 80 mol%, more preferably between 1 mol% and 60 mol%, most preferably between 2 mol% and Between 50 mol%.

  Other polymers, such as unmodified phenolic resins, can also be added to the coating composition. The polymers of the present invention are preferably added to the coating in a concentration range of 5% to 98% by weight of the total coating, more preferably between 10% and 95%.

  If the heat sensitive coating is composed of more than one layer, the polymer of the invention is present in at least one of these layers, for example in the top layer. The polymer can also be present in more than one layer of the coating, for example in the top layer and the intermediate layer.

  The support has a hydrophilic surface or is provided with a hydrophilic layer. The support can be a sheet-like material, for example a plate, or it can be a cylindrical part, for example a sleeve that can slide around a printing cylinder of a printing press. Preferably, the support is a metal support, such as aluminum or stainless steel.

  A particularly preferred lithographic support is an electrochemically polished and anodized aluminum support.

  Polishing and anodizing of an aluminum lithographic support is known. The polished aluminum support used in the material of the present invention is preferably an electrochemically polished support. A polished support. The acid used for polishing is, for example, nitric acid. The acid used for polishing preferably comprises hydrogen chloride. For example, a mixture of hydrogen chloride and acetic acid can be used.

  A polished and anodized aluminum support can be post-treated to improve the hydrophilic properties of its surface. For example, the support can be silicified by treating the surface of the aluminum support with a sodium silicate solution at an elevated temperature, for example, 95 ° C. Alternatively, a phosphating treatment may be applied that involves treating the aluminum oxide surface with a phosphate solution that may further contain inorganic fluoride. Furthermore, the surface of the aluminum oxide is treated with an organic acid and / or a salt thereof such as carboxylic acid, hydroxycarboxylic acid, sulfonic acid or phosphonic acid, or a salt thereof such as oxalate, phosphate, phosphonate, sulfate and The acid salt can be rinsed. Citric acid or citrate solutions are preferred. This treatment can be carried out at room temperature or at a slightly elevated temperature of about 30-50 ° C. Another post-treatment involves rinsing the aluminum oxide surface with a bicarbonate solution. Furthermore, the aluminum oxide surface is produced by reaction with polyvinylphosphonic acid, polyvinylmethylphosphonic acid, phosphoric acid ester of polyvinyl alcohol, polyvinylsulfonic acid, polyvinylbenzenesulfonic acid, sulfuric acid ester of polyvinyl alcohol, and sulfonated aliphatic aldehyde. It can also be treated with an acetal of polyvinyl alcohol. It will also be apparent that one or more of these post treatments may be performed alone or in combination. More detailed descriptions of these processes can be found in British Patent Application No. 1084070, German Patent Application Publication No. 4423140, German Patent Application Publication No. 4417907, European Patent Application Publication No. 659909. European Patent Application Publication No. 537633, German Patent Application Publication No. 4001466, European Patent Application Publication No. 292801, European Patent Application Publication No. 291760 and US Pat. No. 4,458,005. It is shown.

  According to another embodiment, the support can also be a flexible support provided with a hydrophilic layer, hereinafter referred to as “base layer”. The flexible support is, for example, paper, plastic film, thin aluminum or a laminate thereof. Preferable examples of the plastic film include a polyethylene terephthalate film, a polyethylene naphthalate film, a cellulose acetate film, a polystyrene film, and a polycarbonate film. The plastic film support can be opaque or transparent.

  The base layer is preferably a cross-linked hydrophilic layer obtained from a hydrophilic binder cross-linked with a curing agent such as, for example, formaldehyde, glyoxal, polyisocyanate or hydrolyzed tetra-alkyl orthosilicate. The latter is particularly preferred. The thickness of the hydrophilic base layer can vary within the range of 0.2 to 25 μm and is preferably 1 to 10 μm.

  Hydrophilic binders for use in the base layer are for example hydrophilic (co) polymers such as vinyl alcohol, acrylamide, methylol acrylamide, methylol methacrylamide, acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxy methacrylate Homopolymers and copolymers of ethyl, or maleic anhydride / vinyl methyl ether copolymers. The hydrophilicity of the (co) polymer or (co) polymer mixture used is preferably the same as that of polyvinyl acetate hydrolyzed to the extent of at least 60% by weight, preferably 80% by weight. taller than.

  The amount of curing agent, especially tetraalkyl orthosilicate, is preferably at least 0.2 parts by weight per 1 part by weight of hydrophilic binder, more preferably between 0.5 and 5 parts by weight, most preferably 1 to 3 parts by weight. Between.

  The hydrophilic base layer can also contain substances that increase the mechanical strength and porosity of the layer. For this purpose, colloidal silica can be used. The colloidal silica used can be in the form of a commercial aqueous dispersion of colloidal silica having an average particle size of for example up to 40 nm, for example 20 nm. In addition, inert particles larger in size than colloidal silica, such as J.I. Colloid and Interface Sci. , Vol. 26, 1968, pages 62 to 69, silica prepared according to the Stober method, or alumina particles, or particles having an average diameter of at least 100 nm which are particles of titanium dioxide or other heavy metal oxides You can also. By introducing these particles, a uniform rough texture consisting of fine irregularities is given to the surface of the hydrophilic base layer, which acts as a reservoir for water in the background area.

  Specific examples of hydrophilic base layers suitable for use in accordance with the present invention include European Patent Application No. 601240, German Patent No. 1419512, French Patent No. 2300334, US Pat. No. 3,971,660. And U.S. Pat. No. 4,284,705.

It is particularly preferred to use a film support provided with an adhesion improving layer, also called a support layer. Adhesion improving layers which are particularly suitable for use according to the invention are hydrophilic as disclosed in EP 619524, EP 620502 and EP 619525. And a colloidal silica. Preferably, the amount of silica in the adhesion improving layer is between ^{200mg / m 2 ~750mg / m 2} . Furthermore, the ratio of silica to hydrophilic binder is preferably greater than 1 and the surface area of the colloidal silica is preferably at least 300 m ² / gram, more preferably at least 500 m ² / gram.

  The coating applied on the support is heat sensitive and preferably can be handled for several hours under normal working irradiation conditions (daylight, fluorescent light). The coating preferably does not contain UV sensitive compounds having an absorption maximum in the wavelength range of 200 nm to 400 nm, such as diazo compounds, photoacids, photoinitiators, quinonediazides or sensitizers. Preferably, the coating does not contain a compound having an absorption maximum in the blue and green visible light wavelength range between 400 and 600 nm.

  According to one embodiment, the printing plate precursor is positive working, ie, after exposure and development, the exposed areas of the oleophilic layer are removed from the support and define hydrophilic non-image (non-printing) areas. However, the unexposed layer is not removed from the support and defines an oleophilic image (printing) area. According to another embodiment, the printing plate precursor is negative working, i.e. the image area corresponds to the exposed area.

  The coating can comprise one or more separate layers. In addition to the layers discussed below, the coating includes, for example, a “priming layer” that improves the adhesion of the coating to the support, a coating layer that protects the coating from contamination or mechanical damage, and / or an infrared absorbing compound. The light-to-heat conversion layer can further be included.

  A suitable negative working alkaline developer printing plate comprises a phenolic resin and a latent Bronsted acid that generates acid upon heating or infrared irradiation. These acids catalyze the crosslinking of the coating during the post-exposure heating step and consequently catalyze the cure of the exposed areas. Thus, the unexposed areas can be washed away by the developer to reveal the underlying hydrophilic substrate. For a more detailed description of such negative working printing plate precursors, see US Pat. Nos. 6,255,042 and 6,063,544 and references cited in these documents. See literature. In such negative working lithographic printing plate precursors, the polymer of the present invention is added to the coating composition and replaces at least a portion of the phenolic resin.

  With positive working lithographic printing plate precursors, the coating is capable of heat-induced solubilization, i.e., the coating is resistant to developer and ink-receptive in the unexposed state, and heat or infrared. To the extent that the hydrophilic surface of the support thereby emerges upon exposure to.

  In addition to the polymers of the present invention, the coating can contain additional polymeric binders that are soluble in the aqueous alkaline developer. Preferred polymers are phenolic resins such as novolaks, resoles, polyvinylphenols and carboxy-substituted polymers. Representative examples of such polymers are described in German Offenlegungsschrift 4007428, German Offenlegungsschrift 4027301 and German Offenlegungsschrift 4444520.

  In preferred positive working lithographic printing plate precursors, the coating also contains one or more dissolution inhibitors. The dissolution inhibitor reduces the dissolution rate of the hydrophobic polymer in the aqueous alkaline developer in the unexposed areas of the coating and this decrease in dissolution rate is abolished by the heat generated during the exposure and the coating is exposed. It is a compound that dissolves easily in the developer in the defined area. The dissolution inhibitor exhibits a substantial latitude in dissolution rate between the exposed and unexposed areas. Preferably, the dissolution rate inhibitor is good when the exposed coating area is completely dissolved in the developer before the unexposed area is attacked to the extent that the developer's ink-receptive capacity is affected by the developer. A good dissolution rate latitude. One or more dissolution inhibitors can be added to the layer comprising the hydrophobic polymer discussed above.

  The dissolution rate of the unexposed coating in the developer is preferably reduced by the interaction between the hydrophobic polymer and the inhibitor, for example by hydrogen bonding between these compounds. Suitable dissolution inhibitors are preferably at least one aromatic group and a hydrogen bonding site, such as a carbonyl group, a sulfonyl group, or may be quaternized and part of a heterocyclic ring. Or an organic compound comprising a nitrogen atom that may be part of an amino substituent of the organic compound. Suitable dissolution inhibitors of this type have been disclosed, for example, in EP 825927 and 823327.

Water-repellent polymers are another type of suitable dissolution inhibitor. By repelling the aqueous developer from the coating, such polymers appear to increase the developer resistance of the coating. The water-repellent polymer can be added to the layer comprising the hydrophobic polymer and / or can be present in a separate layer where the hydrophobic polymer is applied to the top of the layer. In the latter embodiment, the water-repellent polymer is a coating, as described, for example, in EP 864420, EP 950517 and WO 99/21725. Can be formed and the solubility of the barrier layer in the developer or the penetration of the barrier layer by the developer can be increased by exposure to light or infrared. A preferred example of a water-repellent polymer is a polymer comprising siloxane and / or perfluoroalkyl units. In one embodiment, the coating such water - repellency polymer between 0.5~25mg / ^{m 2,} preferably between 0.5-15 / ^{m 2,} and most preferably 0.5 in an amount of between to 10 mg / ^{m 2.} If the water-repellent polymer is also ink-repellent, for example in the case of polysiloxanes, an amount greater than 25 mg / m ² can lead to poor ink-receptivity in the unexposed areas. On the other hand, amounts less than 0.5 mg / m ² can lead to unsatisfactory development resistance. The polysiloxane can be a linear, cyclic or complex cross-linked polymer or copolymer. The term polysiloxane compound includes compounds containing more than one siloxane group -Si (R, R ')-O-, where R and R' are optionally substituted alkyl or aryl groups. is there. Preferred siloxanes are phenylalkylsiloxanes and dialkylsiloxanes. The number of siloxane groups in the (co) polymer is at least 2, preferably at least 10, more preferably at least 20. It may be less than 100, preferably less than 60. In another embodiment, the water-repellent polymer is a block-copolymer or graft-copolymer of a poly (alkylene oxide) block and a block of a polymer comprising siloxane and / or perfluoroalkyl units. Suitable copolymers comprise about 15 to 25 siloxane units and 50 to 70 alkylene oxide groups. Preferred examples are copolymers comprising phenylmethylsiloxane and / or dimethylsiloxane and ethylene oxide and / or propylene oxide, for example Tego Glide (Tego commercially available from Tego Chemie, Essen, Germany). Glide 410, Tego Wet 265, Tego Protect 5001 or Silikophen P50 / X. Such a copolymer is automatically located at the interface between the coating and air due to its bifunctional structure at the time of coating, so that even when the entire coating is applied from a single coating solution. Acts as a surfactant to form a separate top layer. At the same time, such surfactants act as spreading agents that improve the coating quality. Alternatively, the water-repellent polymer can be applied in the second solution coated on top of the layer comprising the hydrophobic polymer. In this embodiment, it is advantageous to obtain a high concentration water-repellent phase at the top of the coating using a solvent in the second coating solution that is unable to dissolve the components present in the first layer.

  Preferably, one or more development accelerators are included in the coating, i.e., compounds that act as dissolution accelerators to increase the dissolution rate of the unexposed coating in the developer. The simultaneous application of dissolution inhibitors and accelerators allows precise fine tuning of the dissolution performance of the coating. Suitable dissolution promoters are cyclic acid anhydrides, phenols or organic acids. Examples of cyclic acid anhydrides are phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride, as described in US Pat. No. 4,115,128. , Chloromaleic anhydride, alpha-phenylmaleic anhydride, succinic anhydride, and pyromellitic anhydride. Examples of phenol are bisphenol A, p-nitrophenol, p-ethoxyphenol, 2,4,4′-trihydroxybenzophenone, 2,3,4-trihydroxy-benzophenone, 4-hydroxybenzophenone, 4,4 ′, 4. '' -Trihydroxy-triphenylmethane, 4,4 ′, 3 ″, 4 ″ -tetrahydroxy-3,5,3 ′, 5′-tetramethyltriphenyl-methane and the like. Examples of organic acids are sulfonic acid, sulfinic acid, alkyl sulfuric acid, phosphonic acid, phosphate, and the like, as described in, for example, JP-A-60-88,942 and JP-A-2-96,755. Includes carboxylic acid. Specific examples of these organic acids are p-toluenesulfonic acid, dodecylbenzenesulfonic acid, p-toluenesulfinic acid, ethyl sulfuric acid, phenylphosphonic acid, phenylphosphinic acid, phenyl phosphate, diphenyl phosphate, benzoic acid, isophthalic acid, adipic acid , P-toluic acid, 3,4-dimethoxybenzoic acid, phthalic acid, terephthalic acid, 4-cyclohexene-1,2-dicarboxylic acid, erucic acid, lauric acid, n-undecanoic acid, and ascorbic acid. The amount of cyclic acid anhydride, phenol or organic acid contained in the coating is preferably in the range of 0.05 to 20% by weight with respect to the total coating.

  Polymers containing modified phenolic monomer units as described in the polymers of the present invention can be used in conventional photosensitive printing plate precursors where conventional phenolic At least a portion of the system polymer is replaced by at least a portion of the modified polymer as described in the present invention.

  According to a more preferred embodiment, the material of the present invention is imagewise exposed to infrared radiation, which is converted to heat by an infrared absorber, which can be a dye or pigment having an absorption maximum in the infrared wavelength range. The concentration of sensitizing dye or pigment in the coating is typically between 0.25 and 10.0% by weight, more preferably between 0.5 and 7.5% by weight, relative to the entire coating. Preferred infrared absorbing compounds are dyes such as cyanine or merocyanine dyes or pigments such as carbon black. Suitable compounds are the following infrared dyes:

It is.

  The coating may further contain an organic dye that absorbs visible light, resulting in a recognizable image upon image-wise exposure and subsequent development. Such dyes are often referred to as contrast dyes or indicator dyes. Preferably, the dye has blue and an absorption maximum in the wavelength range between 600 nm and 750 nm. Although the dye absorbs visible light, it preferably does not sensitize the printing plate precursor, i.e. the coating does not become more soluble in the developer when exposed to visible light. A suitable example of such a contrast dye is a quaternized triarylmethane dye. Another suitable compound is the following dye:

It is.

  Infrared absorbing compounds and contrast dyes can be present in the layer comprising the hydrophobic polymer and / or in the barrier layer discussed above and / or in other layers optionally present. According to a highly preferred embodiment, the infrared absorbing compound is concentrated in or near the barrier layer, for example in an intermediate layer between the layer comprising the hydrophobic polymer and the barrier layer.

The printing plate precursor of the present invention can be exposed to infrared using an LED or laser. Preferably, a laser that generates near infrared radiation having a wavelength in the range of about 750 to about 1500 nm, such as a semiconductor laser diode, Nd: YAG or Nd: YLF laser is used. The required laser power is determined by the sensitivity of the image recording layer, the pixel dwell time of the laser beam, the scanning speed and the spot diameter (typical of a modern plate-setter at a maximum intensity of 1 / e ² : 10-25 μm) It depends on the resolution of the exposure device (ie often the number of dots per inch or the number of addressable pixels per linear distance unit expressed in dpi; typical values: 1000-4000 dpi).

  Two types of laser-exposure devices are commonly used: an internal drum (ITD) and an external drum (XTD) plate-setter. ITD plate-setters for thermal plates are typically characterized by very high scanning speeds up to 1500 m / sec and may require several watts of laser power. Agfa Galileo T is a representative example of a plate-setter using ITD-technology. XTD plate-setters are typically operated at relatively low scanning speeds of 0.1 m / sec to 10 m / sec and have a typical laser-power per luminous flux of 20 mW to 500 mW. The Creo Trendsetter plate-setter group and the Agfa Excalibur plate-setter group both use XTD-technology.

  Known plate-setters can be used as an off-press exposure device, which provides the advantage of reducing press downtime. The XTD-plate-setter structure can also be used for on-press exposure, providing an immediate register advantage in a multicolor press. Further technical details of on-press exposure devices are described, for example, in US Pat. No. 5,174,205 and US Pat. No. 5,163,368.

  In the development stage, non-image areas of the coating can be removed by immersion in an aqueous alkaline developer, which may be combined with mechanical rubbing, such as with a rotating brush. The developer preferably has a pH greater than 10, more preferably greater than 12. The development stage is followed by a rinsing stage, a gumming stage, a drying stage and / or a post-baking stage.

  The printing plate thus obtained can be used for conventional so-called wet offset printing, in which ink and fountain solution are supplied to the plate. Another suitable printing method uses so-called single fluid inks without fountain solution. Single fluid inks consist of an ink phase, also referred to as a hydrophobic or oleophilic phase, and a polar phase that replaces the dampening water used in conventional offset printing. Suitable examples of single fluid inks are described in US Pat. No. 4,045,232, US Pat. No. 4,981,517 and US Pat. No. 6,140,392. In the most preferred embodiment, the single fluid ink comprises an ink phase and a polyol phase as described in WO 00/32705.

Production of polymer MP-01:
-Diazonium solution:
A mixture of 3.13 g AM-01, 45 ml 1-methoxy-2-propanol and 9 ml water was stirred and cooled to 5 ° C. Then 4.7 ml concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 0.85 g NaNO ₂ in 5 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
137.7 g of POL-01 solution (40 wt%), 11.5 g of NaOAc. A mixture of 3H ₂ O and 225 ml of 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 10 minutes, after which stirring was continued for 30 minutes at 0 ° C. and 2 hours at room temperature. The resulting mixture was then added to 1.5 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-02:
-Diazonium solution:
A mixture of 6.3 g AM-01, 90 ml 1-methoxy-2-propanol and 18 ml water was stirred and cooled to 5 ° C. Then 9.5 ml concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 1.7 g NaNO ₂ in 18 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
137.7 g of POL-01 solution (40% by weight), 23 g of NaOAc. A mixture of 3H ₂ O and 450 ml of 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 20 minutes, after which stirring was continued for 30 minutes at 0 ° C. and 2 hours at room temperature. The resulting mixture was then added to 1.5 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-03:
-Diazonium solution:
A mixture of 12.5 g AM-01, 180 ml 1-methoxy-2-propanol and 36 ml water was stirred and cooled to 5 ° C. Then 19 ml of concentrated HCl was added and the mixture was cooled to 0 ° C. Then a solution of 3.4 g NaNO ₂ in 20 ml in water was added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
137.7 g of POL-01 solution (40 wt%), 46 g of NaOAc. A mixture of 3H ₂ O and 450 ml of 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 30 minutes, after which stirring was continued for 30 minutes at 0 ° C. and 2 hours at room temperature. The resulting mixture was then added to 1.5 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-04:
-Diazonium solution:
A mixture of 31.3 g AM-01, 300 ml 1-methoxy-2-propanol and 90 ml water was stirred and cooled to 5 ° C. Then 47 ml of concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 8.54 g NaNO ₂ in 50 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
137.7 g of POL-01 solution (40 wt%), 115 g of NaOAc. A mixture of 3H ₂ O and 200 ml 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 60 minutes, after which stirring was continued for 30 minutes at 0 ° C. and 2 hours at room temperature. The resulting mixture was then added to 1.5 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-05:
-Diazonium solution:
A mixture of 50 g AM-01, 480 ml 1-methoxy-2-propanol and 145 ml water was stirred and cooled to 5 ° C. Then 75 ml concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 13.6 g NaNO ₂ in 80 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
137.7 g of POL-01 solution (40 wt%), 184 g of NaOAc. A mixture of 3H ₂ O and 400 ml of 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 60 minutes, after which stirring was continued at 0 ° C. for 30 minutes and at room temperature for 2 hours. The resulting mixture was then added to 1.5 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-06:
31.1 g AM-03 was used instead of 31.3 g AM-01 and 137.7 g POL-01 solution (40 wt%) and 115 g NaOAc. 3H ₂ O, except that mixing 1000ml of 1-methoxy-2-propanol in was added instead of 200ml of 1-methoxy-2-propanol, as the production of the polymer MP-06 of the polymer MP-04 Was done in the same way.
Production of polymer MP-07:
-Diazonium solution:
A mixture of 17.4 g AM-01, 80 ml 1-methoxy-2-propanol and 40 ml water was stirred and cooled to 5 ° C. Then 26 ml concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 4.7 g NaNO ₂ in 15 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
30.0 g POL-04 dissolved in 125 ml 1-methoxy-2-propanol and 64 g NaOAc. The 3H ₂ O mixture was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 30 minutes, after which stirring was continued for 30 minutes at 0 ° C. and 2 hours at room temperature. 50 ml of 1-methoxy-2-propanol and 50 ml of N, N-dimethylacetamide were added to dissolve the precipitated product. The resulting mixture was then added to 3 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-08:
-Diazonium solution:
A mixture of 17.4 g AM-01, 80 ml 1-methoxy-2-propanol and 40 ml water was stirred and cooled to 5 ° C. Then 26 ml concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 4.7 g NaNO ₂ in 15 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
30.0 g POL-05 dissolved in 125 ml 1-methoxy-2-propanol and 64 g NaOAc. The 3H ₂ O mixture was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 30 minutes, after which stirring was continued for 30 minutes at 0 ° C. and 2 hours at room temperature. The resulting mixture was then added to 3 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-09:
Except that 30 g of phenolic polymer POL-06 dissolved in 125 ml of 1-methoxy-2-propanol was used instead of POL-05, the production of polymer MP-09 was the same as that of polymer MP-08. Was done in the same way as the ones.
Production of polymer MP-10:
-Diazonium solution:
A mixture of 17.4 g AM-01 and 100 ml acetic acid was stirred and cooled to 5 ° C. Then 15 ml of concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 4.7 g NaNO ₂ in 15 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
30.6 g POL-07 dissolved in 200 ml 1-methoxy-2-propanol, 50 ml N, N-dimethylacetamide and 68 g NaOAc. The 3H ₂ O mixture was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 30 minutes, after which stirring was continued for 30 minutes at 0 ° C. and 2 hours at room temperature. The resulting mixture was then added to 3 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and a water / methanol mixture (volume ratio: 7/3) and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-11:
-Diazonium solution:
A mixture of 27.8 g AM-01, 260 ml 1-methoxy-2-propanol and 78 ml water was stirred and cooled to 5 ° C. Then 42 ml of concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 7.6 g NaNO ₂ in 44 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 10 minutes.
-Phenol polymer solution:
49.0 g POL-08 dissolved in 280 ml N, N-dimethylacetamide and 102 g NaOAc. The 3H ₂ O mixture was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 60 minutes, after which stirring was continued at 0 ° C. for 30 minutes and at room temperature for 2 hours. The resulting mixture was then added to 3.5 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-12:
The production of polymer MP-12 is that of polymer MP-11 except that 48 g of phenolic polymer POL-09 dissolved in 270 ml of N, N-dimethylacetamide was used instead of POL-08. Was done in the same way.
Production of polymer MP-13:
The production of polymer MP-13 is that of polymer MP-11 except that 48 g of phenolic polymer POL-10 dissolved in 280 ml of N, N-dimethylacetamide was used instead of POL-08. Was done in the same way.
Production of polymer MP-14:
The production of polymer MP-14 is that of polymer MP-11 except that 48 g of phenolic polymer POL-11 dissolved in 235 ml of N, N-dimethylacetamide was used instead of POL-08. Was done in the same way.
Production of polymer MP-15:
Polymer MP-15 was prepared except that 13.3 g AM-07 dissolved in 300 ml 1-methoxy-2-propanol and 200 ml water was used instead of AM-01. Performed in the same manner as that of -04.
Production of polymer MP-16:
The production of polymer MP-16 was carried out except that 21.3 g of AM-07 dissolved in 480 ml of 1-methoxy-2-propanol and 180 ml of water was used instead of AM-01. Done in the same way as that of -05.
Production of polymer MP-17:
Using 5.3 g AM-07 dissolved in 120 ml 1-methoxy-2-propanol and 80 ml water and 125.2 g POL-02 solution (44 wt%), 46 g NaOAc. Polymer MP-17 was prepared in the same manner as that of polymer MP-03, except that a mixture of 3H ₂ O and 200 ml of 1-methoxy-2-propanol was used.
Production of polymer MP-18:
Using 13.3 g AM-07 dissolved in 300 ml 1-methoxy-2-propanol and 200 ml water and 125.2 g POL-02 solution (44 wt%), 115 g NaOAc. Except for using a mixture of 1-methoxy-2-propanol 3H ₂ O and 300ml is prepared of the polymer MP-18 was carried out in the same manner as that of polymer MP-04.
Production of polymer MP-19:
-Diazonium solution:
A mixture of 16.1 g AM-08, 299 ml acetic acid and 25 ml concentrated HCl was stirred at 45 ° C. After all AM-08 was dissolved, the solution was cooled to 5 ° C. Concentrated H ₂ SO ₄ was then added and the mixture was further stirred and cooled to 0 ° C. Then a solution of 9.0 g NaNO ₂ in 20 ml in water was added dropwise, after which stirring was continued at 0 ° C. for a further 20 minutes.
-Phenol polymer solution:
137.7 g of POL-01 solution (40 wt%), 68 g of NaOAc. A mixture of 3H ₂ O and 300 ml of 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 30 minutes, after which stirring was continued at 0 ° C. for 30 minutes and at 10 ° C. for 30 minutes. The resulting mixture was then added to 2.5 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and a water / methanol mixture (volume ratio: 6/4) and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-20:
-Diazonium solution:
A mixture of 6.6 g AM-10 and 65 ml acetic acid and 37.5 ml water was cooled to 15 ° C. Then 6.2 ml concentrated HCl was added and the mixture was further cooled to 0 ° C. A solution of 2.8 g NaNO ₂ in 7 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 30 minutes.
-Phenol polymer solution:
45.9 g POL-01 solution (40 wt%), 40.8 g NaOAc. A mixture of 3H ₂ O and 200 ml 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution produced as described above was dropped into the phenol polymer solution over a period of 30 minutes, and then stirring was continued at 15 ° C. for 120 minutes. The resulting mixture was then added to 2 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-21:
A mixture of 5.3 g AM-10 and 50 ml acetic acid was used in the preparation of the diazonium salt, a mixture of 2.3 g NaNO ₂ in 5 ml concentrated HCl and 6 ml water and 32. in the preparation of the phenolic polymer solution. 6 g NaOAc. Manufacture of polymer MP-21 was performed in the same manner as that of polymer MP-20, except that 3H ₂ O was used instead of the amount indicated in the preparation of polymer MP-20.
Production of polymer MP-22:
In the preparation of the diazonium salt, a mixture of 2.6 g AM-10 and 25 ml acetic acid, 2.5 ml concentrated HCl and 1.1 g NaNO _{2 in} 3 ml water was used and in the preparation of the phenolic polymer solution. 16.3 g NaOAc. Manufacture of polymer MP-22 was performed in the same manner as that of polymer MP-20, except that 3H ₂ O was used instead of the amount indicated in the preparation of polymer MP-20.
Production of polymer MP-23:
In the preparation of the diazonium salt, a mixture of 1.33 g AM-10 and 15 ml acetic acid, 1.3 ml concentrated HCl and 0.57 g NaNO _{2 in} 2 ml water was used and in the preparation of the phenolic polymer solution 8.2 g NaOAc. Manufacture of polymer MP-23 was performed in the same manner as that of polymer MP-20, except that 3H ₂ O was used instead of the amount indicated in the preparation of polymer MP-20.
Production of polymer MP-28:
a) First modification reaction for phenolic polymer:
-Diazonium solution:
A mixture of 27.9 g AM-01, 240 ml 1-methoxy-2-propanol and 60 ml water was stirred and cooled to 5 ° C. Then 42 ml of concentrated HCl was added and the mixture was cooled to 0 ° C. A solution of 7.6 g NaNO ₂ in 30 ml in water was then added dropwise, after which stirring was continued at 0 ° C. for a further 20 minutes.
-Phenol polymer solution:
306 g POL-01 solution (40 wt%), 102 g NaOAc. A mixture of 3H ₂ O and 200 ml 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 60 minutes, after which stirring was continued for 30 minutes at 0 ° C. and 2 hours at room temperature. The resulting mixture was then added to 15 liters of ice water over a period of 30 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
b) Second modification reaction for the phenolic polymer:
-Diazonium solution:
A mixture of 2.36 g AM-07, 30 ml 1-methoxy-2-propanol and 20 ml water was stirred and cooled to 5 ° C. Then 8.4 ml of concentrated HCl was added and the mixture was cooled to 0 ° C. Then a solution of 1.52 g NaNO ₂ in 4 ml in water was added dropwise, after which stirring was continued at 0 ° C. for a further 15 minutes.
-First modified phenolic polymer solution:
30.2 g of the first modified pherol polymer dissolved in 200 g of 1-methoxy-2-propanol and 20.4 g of NaOAc. The 3H ₂ O mixture was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the first modified phenolic polymer solution over a period of 30 minutes, after which stirring was continued at 0 ° C. for 30 minutes and at room temperature for 2 hours. 200 ml of acetone was added to the reaction mixture, which was then filtered. The filtrate was then added to 3 liters of ice water over a period of 60 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Production of polymer MP-29:
-Diazonium solution:
A mixture of 13.9 g AM-01, 5.9 g AM-07, 200 ml 1-methoxy-2-propanol and 100 ml water was stirred and cooled to 5 ° C. Then 41 ml of concentrated HCl was added and the mixture was cooled to 0 ° C. Then a solution of 7.6 g NaNO ₂ in 20 ml in water was added dropwise, after which stirring was continued at 0 ° C. for a further 30 minutes.
-Phenol polymer solution:
153 g POL-01 solution (40 wt%), 102 g NaOAc. A mixture of 3H ₂ O and 200 ml 1-methoxy-2-propanol was stirred and cooled to 0 ° C.

The diazonium solution prepared above was added dropwise to the phenolic polymer solution over a period of 60 minutes, after which stirring was continued at 0 ° C. for 30 minutes and at room temperature for 2 hours. The resulting mixture was then added to 5 liters of ice water over a period of 60 minutes with continuous stirring. The polymer precipitated from the aqueous medium and was isolated by filtration. Washing with water and subsequent drying at 45 ° C. finally gave the desired product.
Test 1:
Production of coating:
The following ingredients:
-86.55g Dawanol PM
-464.64 g of methyl ethyl ketone-101.28 g of 2% strength solution of infrared dye IR-1 in Dawanol PM-144.70 g of 1% strength solution of contrast dye CD-1 in Dawanol PM-159. 1% by weight solution of Tego Glide 410 in 14g Dawanol PM-159.14g 40% by weight solution of phenolic polymer listed in Table 1 in Dawanol PM-3.18g 3,4, A coating solution was prepared by mixing 5-trimethoxycinnamic acid.

  The coating solution was coated on an electrochemically polished and anodized aluminum substrate with a wet thickness of 20 μm. The coating was dried at 130 ° C. for 1 minute.

Three solutions were selected to measure chemical resistance:
Test solution 1: 50% strength by weight solution of isopropanol in water,
Test solution 2: EMERAL PREMIUM MXEH commercially available from ANCHOR.
-Test solution 3: ANCHOR AQUA AYDE which is commercially available from Anchor.

Chemical resistance was tested by contacting 40 μl droplets of the test solution at different locations on the coating. After 3 minutes, the droplets were removed from the coating using a cotton pad. The damage on the coating by each test solution was assessed visually as follows:
-0: No damage,
-1: Gloss change on the coating surface,
-2: Small damage to coating (thickness decreases),
-3: Major damage to coating,
-4: completely dissolved coating.

  The higher the rating, the less chemical resistance of the coating. The results for the test solutions on each coating are summarized in Tables 1-4. The table also includes information on the type of phenolic polymer used in the modification reaction, the type of modifying reagent and the degree of modification (mol%) and the number of MPs of the polymer produced.

  The examples in Table 1 show that these polymers modified according to the present invention result in a significant increase in the chemical resistance of the coating compared to the unmodified polymer.

  The examples in Table 2 show that another polymer modified in accordance with the present invention results in a significant increase in the chemical resistance of the coating compared to the unmodified polymer.

  The examples in Table 3 show that these polymers modified according to the invention with different amounts of different types of azo-groups result in a significant increase in the chemical resistance of the coating.

The examples in Table 4 show that these polymers modified according to the present invention in combination of two types of azo-aryl groups result in a significant increase in the chemical resistance of the coating.
Test 2:
Production of coating:
The following ingredients:
-313.45g Dawanol PM
-482.40 g of methyl ethyl ketone-50.64 g of a 2 wt% solution of infrared dye IR-1 in Dawanol PM-72.35 g of a 1 wt% solution of contrast dye CD-1 in Dawanol PM -79. A coating solution was prepared by mixing a 40 wt% solution of the phenolic polymer listed in Table 5 in 57 g of Dawanol PM—1.59 g of 3,4,5-trimethoxycinnamic acid.

Half of the surface of the electrochemically polished and anodized aluminum substrate was coated with the solution prepared above at a wet thickness of 10 μm. The sample was dried for 1 minute at 130 ° C. and rubberized using OZASOL RC515, commercially available from AGFA, to protect the uncoated part of the aluminum.
printing:
The plate is “A + Dick” using “K + E800 Skinnex Black” commercially available from BASF as ink and “Emerald Premium MXEH” commercially available from Anchor as dampening water. ) 360 "installed on a printing press. The number of operations was measured based on the maximum number of prints that could be printed without significant signs of wear on the print area. The operation frequency test was stopped with 100,000 copies. The number of operations is summarized in Table 5. Table 5 also includes information regarding the type of phenolic polymer used in the modification reaction, the type of modifying reagent, the degree of modification (mol%), and the number of MPs in the polymer produced.

The examples in Table 5 show that these polymers modified according to the present invention result in a significant increase in the number of prints of the coating compared to the unmodified polymer.
Test 3:
Production of coating:
The following ingredients:
-209.1 g of tetrahydrofuran-105 g of Dawanol PM in a 40 wt% concentration solution of the phenolic polymer listed in Table 6 -327 g of Dawanol PM
-266 g of methyl ethyl ketone-1.51 g of infrared dye IR-1
-Basonyl Blue 640 commercially available from 54 g of Basf, added as a 1 wt% solution in Dawanol PM.
-A 1 wt% solution of Tego Glide 410 in 32.4 g of Dawanol PM (註: 8.5 g of the solution used in Example 39 instead of 32.4 g of solution)
-A coating solution was prepared by mixing the amounts listed in Table 6 of 3,4,5-trimethoxycinnamic acid, hereinafter referred to as TMCA.

The coating solution was coated on an electrochemically polished and anodized aluminum substrate with a wet thickness of 26 μm using a drying temperature of 130 ° C. at a rate of 8 m / min on the coating line.
Exposure:
The printing plate precursor was exposed on a CreoScitex Trendsetter 3244 with the energy density (mJ / cm ² ) listed in Table 6.
processing:
The image-wise exposed printing plate precursor is processed at a speed of 0.96 m / min and 25 ° C. and is commercially available from Agfa Agfa TD5000 as developer and Agfa Autolith using RC795 as rubber. ) Processed in a T processor.
printing:
The plate was used as a print master on a Sakurai Oliver 52 press using K + E800 Skinex Black, commercially available from Basf as ink and 4% Emerald Premium MXEH as fountain solution. The plate was printed to 100,000 (or 100K) prints and the number of operations was measured as shown in Table 6.

The examples in Table 6 show that these polymers modified according to the present invention result in a significant increase in the number of printing operations of the printing plate.
Test 4:
Production of coating:
The same materials as described in Test 3 were used.

The weight loss rate of the coating was measured on a 10 × 10 cm sample of each of the above printing plate precursors by the following process:
-The weight "A" of each sample was measured,
Soaking these samples in test solution 1 of test 1 for 3 minutes, followed by rinsing with water and drying;
-The weight "B" of each sample was measured,
The heat-sensitive coating of each sample was removed by dissolution with methyl-ethyl-ketone (if the coating was not completely removed, other suitable solvents such as acetone, tetrahydrofuran, dawanol PM, methanol or butyrolactone, for example) Can be used),
-These samples were rinsed with water and dried,
-The weight "C" of each sample was measured,
-The weight loss rate of each sample is represented by the following formula:
(AB) × 100% / (AC)
Calculated by

  The results are summarized in Table 7.

The examples in Table 7 show a coating with a very low printing plate precursor comprising in the coating one of these polymers modified according to the invention with different amounts of different types of azo-aryl groups. This indicates that the chemical resistance is significantly increased. All other Examples 1-39 also showed a weight loss of less than 45%.
Test 5:
Production of coating:
Comparative Example 15 and Inventive Example 44 were prepared in the same manner as Comparative Example 13 and Example 39 described in Test 3 and shown in Table 6.

Chemical resistance was measured in the same way except that Test Solution 4 and Test Solution 5 were used instead of Test Solution 1, 2 or 3:
Test solution 4: METER-X is a metering and dampening roller cleaner commercially available from ABC CHEMICAL CORP. LTD.
Test solution 5: Wash R-228 is a roller and blanket cleaner available from Anchor.

  For evaluation, the same evaluation as in Table 1 is used and the results are summarized in Table 8.

Example 44 in Table 8 shows that a polymer-based coating modified in accordance with the present invention results in a significant increase in chemical resistance to printing press chemicals.
Test 6:
The following ingredients:
-10.12 g of tetrahydrofuran-5.54 g of Dawanol PM in a 40 wt% solution of the phenolic polymer listed in Table 9-19.7 g of Dawanol PM
-12.9 g of methyl ethyl ketone-0.12 g of infrared dye IR-1
-1.16 g of Cymel 303 available from DYNO CYTEC
A coating solution was prepared by mixing -0.3 g 3,4,5-trimethoxycinnamic acid.

The coating solution was coated on an electrochemically polished and anodized aluminum substrate with a wet thickness of 16 μm. The coating was dried at 90 ° C. for 5 minutes.
Exposure and preheating:
The printing plate precursor was exposed on Creositex Trendsetter 3244 with an exposure energy density of 300 mJ / cm ² . The printing plate precursor was then heated to 110 ° C. for 1 minute.
processing:
The imagewise exposed and preheated printing plate precursor was processed using New Unidev, commercially available from Agfa, as a developer, thereby removing non-image areas. The final printing plate was obtained after rinsing with water.

  To determine chemical resistance, the same test process as shown in Test 1 was used. The results for the test solutions on each coating are summarized in Table 9, where the type of phenolic polymer used in the modification reaction, the type of modifying reagent, the degree of modification (mol%) and the produced Information on the MP number of the polymer is also shown.

Note: The lower chemical resistance value for this negative working comparative example 16 is explained by the fact that the image area of this negative working version is cross-linked, which is not the case for the positive working example.

  Examples 45 and 46 in Table 9 show that a negative working coating comprising a polymer modified according to the present invention results in a significant increase in chemical resistance.

Claims (18)

A thermosensitive lithographic printing plate precursor comprising a hydrophilic surface and a support having a lipophilic coating provided on the hydrophilic surface, the coating comprising -an infrared absorber and a phenolic monomer unit A phenol in which the phenyl group is substituted by a group having the structure -N = N-Q, wherein the -N = N- group is covalently bonded to the carbon atom of the phenyl group and Q is an aromatic group. A heat-sensitive lithographic printing plate precursor comprising a polymer comprising a monomer unit.   2. A lithographic printing plate precursor according to claim 1 wherein Q comprises at least one heteroatom.   The lithographic printing plate precursor according to claim 2, wherein the heteroatom is a nitrogen, oxygen or sulfur atom. Q is the structure -A- (T) _n
[Wherein A is a monocyclic 5- or 6-membered aromatic group or a 5- or 6-membered aromatic ring fused with another ring system;
n is an integer selected between 0 and the maximum available position on the aromatic group A;
Each T group is —SO ₂ —NH—R ¹ , —NH—SO ₂ —R ⁴ , —CO—NR ¹ —R ² , —NR ¹ —CO—R ⁴ , —NR ¹ —CO—NR ² —R. ³ , —NR ¹ —CS—NR ² —R ³ , —NR ¹ —CO—O—R ¹ , —O—CO—NR ¹ —R ² , —O—CO—R ⁴ , —CO—O—R ² , —CO—R ³ , —SO ₃ —R ¹ , —O—SO ₂ —R ⁴ , —SO ₂ —R ¹ , —SO—R ⁴ , —P (═O) (— O—R ¹ ) ^{(-O-R 2), -} O-P (= O) (- O-R 1) (- O-R 2), - NR 1 -R 2, -O-R 2, -S-R 2, -N = NR ⁴ , -CN, -NO ₂ , halogenide or -M-R ¹ , M represents a divalent linking group having 1 to 8 carbon atoms,
R ¹ , R ² and R ³ are each independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁴ and R ⁵ are selected from optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
Or at least two groups selected from each of R ^{1 to} R ⁵ together represent the atoms necessary to form a cyclic structure]
The lithographic printing plate precursor according to claim 1, 2 or 3. -N = NQ group is represented by the following formula

[Wherein X is CR ³ , NR ⁴ or N;
Y represents an atom necessary to form a 5- or 6-membered aromatic ring, and the atom is selected from the group consisting of CR ³ , NR ⁴ , N, S or O;
Each R ¹ , R ² and R ³ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ⁵ , —NH—SO ₂ —R ⁷ , —CO—NR ⁵ —R ⁶ , —NR ⁵ —CO—R ⁷ , —O—CO—R ⁷ , —CO—O—R ⁵ , —CO—R ⁵ , —SO ₃ —R ⁵ , —SO ₂ —R ⁵ , —SO ₂ —R ⁷ , —P (═O) (— O—R ⁵ ) (— O—R ⁶ ), —NR ⁵ —R ⁶ , Selected from —O—R ⁵ , —S—R ⁵ , —CN, —NO ₂ , halogen or —M—R ⁵ , wherein M represents a divalent linking group having 1 to 8 carbon atoms;
R ⁴ , R ⁵ and R ⁶ are independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁷ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁷ together represent the atoms necessary to form a cyclic structure]
A lithographic printing plate precursor according to any one of claims 1 to 3. -N = NQ group is represented by the following formula

[Wherein Z ¹ and Z ² are independently selected from CR ¹ or N;
R ¹ is selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
n is 0, 1, 2, 3 or 4;
m is 0, 1, 2 or 3,
R ² and R ³ are hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ⁴ , —NH —SO ₂ —R ⁶ , —CO—NR ⁴ —R ⁵ , —NR ⁴ —CO—R ⁶ , —O—CO—R ⁶ , —CO—O—R ⁴ , —CO—R ⁴ , —SO ₃ —R ⁴ , —SO ₂ —R ⁴ , —SO—R ⁶ , —P (═O) (— O—R ⁴ ) (— O—R ⁵ ), —NR ⁴ —R ⁵ , —O—R ⁴ , —S—R ⁴ , —CN, —NO ₂ , halogen or —M—R ⁴ , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ⁴ and R ⁵ are independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁶ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁶ together represent the atoms necessary to form a cyclic structure]
A lithographic printing plate precursor according to any one of claims 1 to 3. -N = NQ group is represented by the following formula

[Wherein n is 0, 1, 2, 3, 4 or 5;
Each R ¹ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ² , —NH—SO _{^{2 -R 4, -CO-NR 2}} -R 3, -NR 2 -CO-R 4, -O-CO-R 4, -CO-O-R 2, -CO-R 2, -SO 3 -R ² , —SO ₂ —R ² , —SO—R ⁴ , —P (═O) (— O—R ² ) (— O—R ³ ), —NR ² —R ³ , —O—R ² , — Selected from S—R ² , —CN, —NO ₂ , halogen or —M—R ² , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ² and R ³ are independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁴ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁴ together represent the atoms necessary to form a cyclic structure]
A lithographic printing plate precursor according to any one of claims 1 to 3. -N = NQ group is represented by the following formula

[Wherein n is 0, 1, 2, 3 or 4;
Each R ¹ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ² , —NH—SO _{^{2 -R 4, -CO-NR 2}} -R 3, -NR 2 -CO-R 4, -O-CO-R 4, -CO-O-R 2, -CO-R 2, -SO 3 -R ² , —SO ₂ —R ² , —SO—R ⁴ , —P (═O) (— O—R ² ) (— O—R ³ ), —NR ² —R ³ , —O—R ² , — Selected from S—R ² , —CN, —NO ₂ , halogen or —M—R ² , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
X is O, S or NR ⁵ ;
R ² , R ³ and R ⁵ are independently selected from hydrogen or optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl groups;
R ⁴ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁵ together represent the atoms necessary to form a cyclic structure]
A lithographic printing plate precursor according to any one of claims 1 to 3. -N = NQ group is represented by the following formula

[Wherein n is 0, 1, 2 or 3;
Each R ¹ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ² , —NH—SO _{^{2 -R 4, -CO-NR 2}} -R 3, -NR 2 -CO-R 4, -O-CO-R 4, -CO-O-R 2, -CO-R 2, -SO 3 -R ² , —SO ₂ —R ² , —SO—R ⁴ , —P (═O) (— O—R ² ) (— O—R ³ ), —NR ² —R ³ , —O—R ² , — Selected from S—R ² , —CN, —NO ₂ , halogen or —M—R ² , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ² , R ³ , R ⁵ and R ⁶ are independently selected from hydrogen or an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group ,
R ⁴ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Alternatively, at least two groups selected from each R ^{1 to} R ⁴ together represent the atoms necessary to form a cyclic structure,
Or R ⁵ and R ⁶ together represent the atoms necessary to form a cyclic structure]
A lithographic printing plate precursor according to any one of claims 1 to 3. -N = NQ group is represented by the following formula

[Wherein n is 0, 1, 2 or 3;
m is 0, 1, 2, 3 or 4;
Each R ¹ and R ² is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ³ , — NH—SO ₂ —R ⁵ , —CO—NR ³ —R ⁴ , —NR ³ —CO—R ⁵ , —O—CO—R ⁵ , —CO—O—R ³ , —CO—R ³ , —SO _3- R ³ , —SO ₂ —R ³ , —SO—R ⁵ , —P (═O) (— O—R ³ ) (— O—R ⁴ ), —NR ³ —R ⁴ , —O—R ³ , —S—R ³ , —CN, —NO ₂ , halogen or —M—R ³ , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ³ and R ⁴ are independently selected from hydrogen or an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
R ⁵ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁵ together represent the atoms necessary to form a cyclic structure]
A lithographic printing plate precursor according to any one of claims 1 to 3. -N = NQ group is represented by the following formula

[Wherein n is 0, 1, 2 or 3;
Each R ¹ is hydrogen, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group, —SO ₂ —NH—R ² , —NH—SO _{^{2 -R 4, -CO-NR 2}} -R 3, -NR 2 -CO-R 4, -O-CO-R 4, -CO-O-R 2, -CO-R 2, -SO 3 -R ² , —SO ₂ —R ² , —SO—R ⁴ , —P (═O) (— O—R ² ) (— O—R ³ ), —NR ² —R ³ , —O—R ² , — Selected from S—R ² , —CN, —NO ₂ , halogen or —M—R ² , wherein M represents a divalent linking group having 1 to 8 carbon atoms,
R ² , R ³ , R ⁵ and R ⁶ are independently selected from hydrogen or an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclic, aryl, heteroaryl, aralkyl or heteroaralkyl group ,
R ⁴ is selected from an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, heterocycle, aryl, heteroaryl, aralkyl or heteroaralkyl group;
Or at least two groups selected from each of R ^{1 to} R ⁶ together represent the atoms necessary to form a cyclic structure]
A lithographic printing plate precursor according to any one of claims 1 to 3. The —N═NQ group is represented by the following formula:

The lithographic printing plate precursor according to any one of claims 1 to 3, comprising one of the following.   The lithographic printing plate precursor according to any one of claims 1 to 12, wherein the polymer comprising a phenolic monomer unit is novolak, resol or polyvinylphenol.   The lithographic printing plate precursor according to any of claims 1 to 13, wherein the coating further comprises a dissolution inhibitor and the precursor is a positive working lithographic printing plate precursor. 15. The dissolution inhibitor according to claim 14, wherein the dissolution inhibitor is selected from: an organic compound comprising at least one aromatic group and a hydrogen bonding site, and / or a polymer or surfactant comprising a siloxane or perfluoroalkyl unit. The lithographic printing plate precursor described. To increase the chemical resistance of the coating to printing fluids and printing chemicals,
The phenyl group of the phenolic monomer unit in the coating of a positive working thermosensitive lithographic printing plate precursor further comprising an infrared absorber and a dissolution inhibitor, wherein the phenyl group of the phenolic monomer unit has the structure -N = NQ Use of a polymer comprising a phenolic monomer unit substituted by a group having the —N═N— group covalently bonded to the carbon atom of the phenyl group and Q being an aromatic group.   14. The coating according to any one of claims 1 to 13, wherein the coating further comprises a latent Bronsted acid and an acid-crosslinkable compound and the precursor is a negative working lithographic printing plate precursor. A lithographic printing plate precursor. To increase the chemical resistance of the coating to printing fluids and printing chemicals,
-Infrared absorbers,
The phenyl group of the phenolic monomer unit in the coating of a negative working thermosensitive lithographic printing plate precursor further comprising a latent Bronsted acid and an acid-crosslinkable compound -N = NQ Wherein the —N═N— group is covalently bonded to the carbon atom of the phenyl group and Q is an aromatic group. Use of coalescence.