Offset printing plate precursor, method of use, and method of manufacture

Abstract

The original printing plate precursor of a negative-type infrared-sensitive lithographic printing plate capable of on-press development has an aluminum-containing substrate having at least an inner aluminum oxide layer and an outer aluminum oxide layer. A hydrophilic layer is present on the outer aluminum oxide layer and contains a phosphorus-containing compound represented by the formula (I) in a coating amount of 50 to 300 mg / m 2 . The hydrophilic polymer may also be present in a coating amount smaller than that of the phosphorus-containing compound. These original printing plate precursors have a negative-type infrared-sensitive image-forming layer capable of on-press development, which has at least a free-radical polymerizable component, an initiator composition that gives free radicals when exposed to image-forming infrared rays, an infrared absorber having an anionic chromophore, and optionally, a polymer binder different from all other components. Such original printing plate precursors can provide a lithographic printing plate by image formation and on-press development, and can be easily manufactured using a specific series of steps including a plurality of anodization steps.

Description

Technical Field

[0001] The present invention relates to an on-machine developable negative-type infrared-sensitive lithographic printing plate precursor (hereinafter referred to as "precursor") including an aluminum-containing substrate of the present invention. The aluminum-containing substrate is manufactured using at least two separate anodization processes for providing at least an inner aluminum oxide layer and an outer aluminum oxide layer. The aluminum-containing substrate also has a unique hydrophilic layer disposed on the outer aluminum oxide layer, and this hydrophilic layer has a dominant dry coating amount of a phosphorus-containing compound at a specific dry coating amount. The present invention also relates to a method for providing a lithographic printing plate by subjecting such a precursor to infrared image formation and processing. The present invention further relates to a method for manufacturing such a precursor of the present invention from the aluminum-containing substrate of the present invention.

Background Art

[0002] In lithographic printing, a lithographic ink-receptive area known as an image area is formed on a hydrophilic surface of a substrate. When the printing plate surface is wetted with water and lithographic printing ink is applied, the hydrophilic area retains water and repels the lithographic printing ink, and the lithographic ink-receptive image area accepts the lithographic printing ink and repels water. The lithographic printing ink is transferred from the lithographic printing plate to the surface of the material on which the image is reproduced, probably using a blanket roller.

[0003] The image-formable element used for manufacturing a lithographic printing plate, that is, a lithographic printing plate precursor, typically includes one or more radiation-sensitive image-formable layers disposed on the outermost hydrophilic surface of a substrate. After image formation, either the exposed area (image-formed area) or the unexposed area (non-image-formed area) of one or more radiation-sensitive layers is removed using an appropriate developer, and the outermost hydrophilic surface of the substrate may be exposed. If the exposed area is removable, the lithographic printing plate precursor is regarded as positive-type. Conversely, if the unexposed area is removable, the lithographic printing plate precursor is regarded as negative-type.

[0004] The radiation-sensitive photopolymerizable composition used for a negative-type lithographic printing plate original typically contains a free-radical polymerizable component, one or more radiation absorbers, an initiator composition, and optionally one or more polymer binders different from the other components described above.

[0005] In recent decades, the industry has focused on simplifying the manufacturing process of lithographic printing plates, including omitting the preheating step (preheating) before development and performing on-press development (DOP) using lithographic printing ink, dampening water, or both to remove unnecessary (unexposed) image-forming layer materials on the lithographic printing plate original. Such negative-type lithographic printing plate originals must be designed by balancing many features in the element structure in order to obtain optimal printing life, on-press developability, image formation speed, storage stability, and scratch resistance, among other characteristics required in the industry. Since a chemical composition or structural feature that can provide an optimal level in one or two characteristics can cause a loss in another characteristic, it has not been an easy task to optimize all of these characteristics simultaneously.

[0006] Advances in the art for on-press developable lithographic printing plate originals include the uniquely anodized substrate described in U.S. Patent Application Publication No. 2018 / 0250925 (Merka et al.).

[0007] There is still a need to reduce the adverse effect of atmospheric ozone on the chemical reactions of image formation in the original. Ozone may reduce the image formation sensitivity of certain infrared absorbers, i.e., infrared absorbers having a cationic chromophore with a net positive charge. Originals having such compounds may exhibit a decrease in printing durability. To solve this problem, researchers have found that it is useful to use an infrared absorber containing an anionic chromophore having a net negative charge or an acidic group in the chemical reaction of image formation of the image-forming layer.

[0008] However, when using such "anionic" infrared absorbers, as described in U.S. Patent Application Publication No. 2018 / 0250925 (Merka et al.), another problem occurs when applying an image-forming layer to an aluminum-containing substrate having a plurality of aluminum oxide layers produced using sulfuric acid in the final anodization process. Such anodization can produce water-soluble aluminum sulfate, which can migrate into the image-forming layer and form aluminum salts with the anionic infrared absorber. As a result, the image-forming sensitivity of these infrared absorbers is significantly reduced.

[0009] Therefore, it is necessary to solve these multiple problems without sacrificing image-forming sensitivity and printing durability.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

[0011] The present invention provides the following lithographic printing plate original: A lithographic printing plate original comprising: An aluminum-containing substrate having a hydrophilic surface; and An on-press developable negative-type infrared-sensitive image-forming layer disposed on the hydrophilic surface of the aluminum-containing substrate, wherein the aluminum-containing substrate is An aluminum-containing plate having a granulated and etched surface, An inner aluminum oxide layer disposed on a granulated and etched surface, having an average dry thickness (T i ) of at least 300 nm to 3000 nm or less, containing a number of inner pores with an average inner pore diameter (D i ) of 11 nm or less, and containing aluminum sulfate, the inner aluminum oxide layer, An outer aluminum oxide layer disposed on the inner aluminum oxide layer, containing a number of outer pores with an average outer pore diameter (D o ) of at least 12 nm to 50 nm or less, and having an average dry thickness (T o ) of at least 20 nm to 650 nm or less, the outer aluminum oxide layer, and A hydrophilic layer disposed on the outer aluminum oxide layer, The hydrophilic layer is (1) having a C1 dry coating amount, and one or more phosphorus-containing compounds represented by the following formula (I):

Chemical formula

[0012] The present invention also provides a method for providing the following lithographic printing plate: A method for providing a lithographic printing plate, comprising: Imagewise exposing a lithographic printing plate precursor according to any of the embodiments of the present invention to imagewise infrared light to form an imagewise infrared-exposed image-forming layer having exposed and unexposed regions, and Removing the unexposed regions from the imagewise infrared-exposed image-forming layer on press using a lithographic printing ink, dampening water, or both a lithographic printing ink and dampening water to form a lithographic printing plate A method comprising

[0013] Furthermore, the present invention provides a method for manufacturing the following lithographic printing plate precursor: A method for manufacturing a lithographic printing plate precursor, comprising: A) Providing an aluminum-containing plate having an electrochemically or mechanically grained and etched surface; B) Subjecting the aluminum-containing plate to a first anodization process to form an outer aluminum oxide layer on the electrochemically or mechanically grained and etched surface, wherein the outer aluminum oxide layer comprises a plurality of outer pores having an average outer pore diameter (D o ) of at least 12 nm to 50 nm or less, and having an average dry thickness (T o ) of at least 20 nm to 650 nm or less, subjecting to the first anodization process; C) Rinsing the outer aluminum oxide layer; D) Subjecting the aluminum-containing plate to an additional anodization process using sulfuric acid to form an inner aluminum oxide layer under the outer aluminum oxide layer, wherein the inner aluminum oxide layer has an average dry thickness (T i) having, an average inner pore diameter (D i ) containing a large number of inner pores with an average inner pore diameter of 11 nm or less, and the inner aluminum oxide layer contains aluminum sulfate, a step of subjecting to an additional anodization process, E) A step of rinsing the outer aluminum oxide layer and the inner aluminum oxide layer, F) A step of providing a hydrophilic layer on the outer aluminum oxide layer, wherein the hydrophilic layer (1) has a C1 dry coating amount and the following formula (I):

Chemical formula

[0014] In some embodiments of this manufacturing method of the present invention, this method includes, between step C) and step D), C’) A step of subjecting an aluminum-containing plate to a second anodization process to form an intermediate aluminum oxide layer under the outer aluminum oxide layer, wherein the intermediate aluminum oxide layer has an average dry thickness (T m ) of at least 60 nm to 300 nm or less, contains a large number of intermediate pores having an average intermediate pore diameter (D m ) of at least 20 nm to 60 nm or less, D m is larger than D o , D o is larger than D i , and the average dry thickness (T o ) of the outer aluminum oxide layer is less than 150 nm, further including a step of subjecting to a second anodization process, The additional anodization process of step D) is a third anodization process for forming an inner aluminum oxide layer under the intermediate aluminum oxide layer.

[0015] In the chemical reaction of image formation, the problem that the image formation sensitivity decreases when an anionic infrared absorber is present has been significantly reduced by the implementation of the present invention. Specifically, when an anionic infrared absorber is used in the chemical reaction of image formation, it has been found that if phosphoric acid, a phosphoric acid condensate, or a phosphate constitutes the main component of the hydrophilic layer located between the aluminum-containing substrate and the on-machine developable negative-type infrared-sensitive image-forming layer, the image formation sensitivity is maintained. These advantages are particularly evident when the aluminum-containing substrate has two or more aluminum oxide layers produced by anodization treatment and the last anodization treatment is performed using sulfuric acid. Anodized aluminum produced using sulfuric acid contains aluminum sulfate. Aluminum sulfate is readily water-soluble in its pure form, but the aluminum sulfate trapped within the anodized aluminum structure cannot be easily removed by a water rinsing process within a practical time frame of a typical printing plate original manufacturing machine. During the natural storage of a lithographic printing plate original derived from such an aluminum-containing substrate, especially in a humid environment, the aluminum sulfate retained in the aluminum-containing substrate can be slowly released.

[0016] The migration of the released aluminum sulfate to the on-machine developable negative-type infrared-sensitive image-forming layer can be effectively blocked by one or more phosphorus-containing compounds (1) present in a C1 dry coating amount of at least 50 mg / m 2 ~300 mg / m 2 It has been found that the following. Therefore, salt formation between the anionic chromophore of one or more infrared absorbers (c) and the aluminum ions of the aluminum sulfate released from the aluminum-containing substrate can be effectively prevented. Such salt formation, if not prevented, significantly reduces the effectiveness of one or more infrared absorbers (c).

Mode for Carrying Out the Invention

[0017] Definition The term "aluminum-containing plate" is used herein to refer to an aluminum-containing material or other metal-containing material (sheet, web, piece, sheet, foil, or other form) that can be processed later to produce a "substrate", as described in more detail below. In some cases, this term is known in the art as a "support".

[0018] The average outer pore diameter (D in nanometers (nm)) o ) can be determined from a top surface SEM image at a magnification of at least 50,000X taken from the substrate surface before the application of the hydrophilic layer and the infrared-sensitive image-forming layer. The outer pore diameter (D o ) of the original lithographic printing plate can also be determined by stripping off the organic layer with a suitable solvent and, if necessary, removing the outer portion of the outer aluminum oxide layer with a thickness of about 20 nm to 80 nm using a suitable technique such as argon ion beam sputtering before taking a top view SEM image. This average value can be determined by examining more than 200 outer pores.

[0019] The average inner pore diameter (D i ) can be determined from a cross-sectional SEM image at a magnification of at least 50,000X. The cross-section can be generated by bending the original lithographic printing plate or its substrate after the image-forming layer and the hydrophilic layer have been removed. While bending, cracks are formed in the aluminum oxide layer, and a new surface is usually formed at the weakest position, which is usually located at the thinnest wall between adjacent inner pores. Therefore, the new crack surface gives a cross-sectional view of many pores. In the case of the present invention, as long as at least 90% of the exposed pore cross-sections have a width of less than 11 nm, it is not necessary to determine the exact average inner pore diameter (D i ).

[0020] The average dry thickness (T of the outer aluminum oxide layer in nanometers (nm)) o ), the average dry thickness of the intermediate aluminum oxide layer, and the average dry thickness of the inner aluminum oxide layer (T i) can be determined respectively from cross-sectional SEM images at a magnification of at least 50,000X. The cross-section of the aluminum oxide layer can be exposed by cracks formed by bending the lithographic printing plate original or its aluminum-containing substrate. The cross-section of each aluminum oxide layer can also be exposed by cutting a groove through the aluminum oxide layer with a focused ion beam (FIB), which is a technique well-known in the art.

[0021] In some embodiments, pores / μm 2 The pore density (C o ) of the outer aluminum oxide layer per unit can be determined from a top surface SEM photograph at a magnification of at least 50,000X by counting the number of pores in a predetermined square region having an area of, for example, 500 nm × 500 nm.

[0022] Furthermore, in some embodiments, the porosity (P o ) of the outer aluminum oxide layer can be restricted by each of the following formulas: 0.3 ≤ P o ≤ 0.8 or 0.3 ≤ P o ≤ 0.6 (wherein P o is defined as 3.14(C o )(D o 2 ) / 4,000,000).

[0023] As used herein, the term "infrared absorber" refers to a compound or material that absorbs electromagnetic radiation in a specified region, typically a compound or material having an absorption maximum in the region of at least 750 nm to 1400 nm, or a mixture thereof.

[0024] To clarify the definition of all terms related to polymers, refer to "Glossary of Basic Terms in Polymer Science" published by the International Union of Pure and Applied Chemistry (IUPAC), Pure Appl. Chem. 68, 2287 - 2311 (1996). However, any definition explicitly stated in this specification should be regarded as dominant.

[0025] Unless otherwise indicated, the term "weight %" refers to the amount of a component or material relative to the total solids of a composition, formulation, or dry layer. Unless otherwise indicated, the percentage can be the same for either the dry layer or the total solids of the formulation or composition used to form the dry layer.

[0026] Use The original lithographic printing plate of the present invention (the "original plate of the present invention") is useful for forming a lithographic printing plate for lithographic printing using, for example, lithographic printing ink, dampening water, or both lithographic printing ink and dampening water. These original plates are manufactured using the structures and components described below. Also, the original lithographic printing plate of the present invention is designed to be negative and developable on - press to provide a negative - type infrared - sensitive formulation and an image - formable layer using the appropriate materials and manufacturing procedures described below.

[0027] However, if the user desires, it is still possible to develop such an original plate of the present invention off - press using an appropriate developer.

[0028] The substrate of the present invention Generally, an aluminum-containing substrate of a lithographic printing plate can be derived from an aluminum alloy containing up to 10% by weight of one or more elements including, but not limited to, aluminum or other metallic materials such as manganese, silicon, iron, titanium, copper, magnesium, chromium, zinc, bismuth, nickel, and zirconium. The aluminum-containing or aluminum alloy-containing support (or "plate" or "starting material") can have any form that can be further processed as long as it has at least one surface (substantially flat) that can be treated as described below to form a hydrophilic surface in the substrate of the present invention, and these forms include sheets, continuous webs, and coil-shaped pieces. It is also possible to deposit or laminate a pure aluminum-containing layer or an aluminum alloy-containing layer on the upper layer using a polymer film or paper.

[0029] The resulting aluminum-containing substrate must be thick enough to mechanically withstand the conditions of modern printing presses, but thin enough to be installed (or run along) on the printing cylinder of such a printing press. Thus, the aluminum-containing substrate must also have appropriate tensile strength, elasticity, crystallinity, and conductivity required for lithographic printing. These properties can be obtained by standard methods such as heat treatment or cold and hot rolling typical in the manufacture of continuous lithographic printing support sheets, webs, or coils. The dry thickness of the resulting substrate of the present invention is generally at least 100 μm to 600 μm or less.

[0030] The above-mentioned aluminum-containing plate can be processed using a typical manufacturing process of a lithographic printing plate original, such as pre-etching, water rinsing, roughening, water rinsing, post-etching, and a final water rinsing procedure, in combination with two or more anodization processes described in more detail below.

[0031] The aluminum-containing plate (or support) of the raw material is typically subjected to a preliminary etching process to remove contaminants such as oils and fats, and metals on or near the surface of the support. As is known in the art, this preliminary etching process can be carried out using sodium hydroxide or other alkaline aqueous solutions, and further using specific organic solvents at known concentrations, times, and temperatures. If desired, an aqueous surfactant solution can be used to carry out a separate or additional degreasing process. A person skilled in the art will be able to find the optimal preliminary etching conditions (e.g., optimal solution concentration, residence time, and temperature) through routine experiments.

[0032] Typically, after the preliminary etching process, the etched support is "roughened" in a suitable manner, such as using a known electrochemical or mechanical roughening (or granulation) process. In the electrochemical granulation process, the etched support can be processed with an alternating current in a solution of hydrochloric acid at 5 - 20 g / liter. For this purpose, it is also possible to use a solution of nitric acid or sulfuric acid, or a mixture (e.g., up to 2.5 wt%). Such electrochemical granulation solutions may also contain additives, such as corrosion inhibitors and stabilizers, including but not limited to metal nitrates, metal chlorides, monoamines, diamines, aldehydes, phosphoric acid, chromic acid, boric acid, lactic acid, acetic acid, and oxalic acid. For example, electrochemical granulation can be carried out using the process described in U.S. Patent Application Publication No. 2008 / 0003411 (Hunter et al.). Since such processes are well-known in the art, a person skilled in the art will be able to determine the optimal conditions for electrochemical or mechanical granulation through routine experiments. The mechanical granulation process can be carried out, for example, using a suitable brush alone or in combination with a slurry of abrasives, such as silica particles or alumina particles. Alternatively, a combination of a mechanical granulation process and an electrochemical granulation process can be used.

[0033] During roughening or granulation, a matte may form on the surface of the aluminum-containing support, but this matte is removed in a post-etching step using treatment with a highly acidic or highly alkaline solution, for example, from 0.01 to 5.0 g / m of the support surface 2 can be removed. For example, post-etching can be carried out using a solution of sodium hydroxide, trisodium phosphate, or sulfuric acid. The amount of post-etching can be controlled by setting the residence time, concentration, and temperature of the etching solution. The appropriate amount of post-etching also depends on the amount of roughening and the amount of matte formed in the process. The post-etching treatment must be sufficient to remove the matte, but should not overly damage the surface structure formed in the roughening step. Thus, there are many combinations of parameters that a person skilled in the art can consider while conducting routine experiments to find the optimal post-etching conditions.

[0034] The above process results in an electrochemically or mechanically granulated (roughened) and etched surface in an aluminum-containing plate (or support) that can be provided in step A) of the manufacturing method according to the present invention.

[0035] The next steps carried out according to the present invention generally include at least a first anodization process and a second anodization process, both of which are essential for the present invention to form outer and inner aluminum oxide layers respectively. The method of the present invention does not require additional anodization processes (i.e., a third or subsequent anodization process), but one or more additional anodization processes are possible and thus may be carried out optionally.

[0036] The first and second anodization processes generally use a sulfuric acid or phosphoric acid solution (electrolyte) for an appropriate time, at least from 20 °C to 70 °C or less, for at least 1 second to 250 seconds or less, 4 g / m 2It can be carried out so as to give the following total dry aluminum oxide coating amount (the sum of the aluminum oxide layers on both the outer and inner sides). The conditions for both the first and second anodization processes are described below.

[0037] Accordingly, a suitable aluminum-containing plate having an electrochemically or mechanically granulated and etched surface as described above is subjected to a first anodization process in step B), and an outer aluminum oxide layer is formed on the electrochemically or mechanically granulated and etched surface. The first anodization process can be carried out using an electrolyte composition containing, for example, at least 50 g / l to 350 g / l or less of phosphoric acid, or at least 150 g / l to 300 g / l or less of sulfuric acid, and an appropriate amount, for example, 5 g / l of aluminum ions. These solution amounts can be optimized with respect to the type of acid, acid concentration, aluminum ion concentration, residence time, and temperature in order to obtain the desired outer aluminum oxide layer characteristics described herein. Representative details of such a first anodization process are shown in the examples described below, or in known techniques, such as U.S. Patent Application Publication No. 2018 / 0250925 (Merka et al.), U.S. Patent No. 9,259,954 (Tagawa et al.), U.S. Patent No. 8,978,555 (Kurokawa et al.), U.S. Patent No. 8,789,464 (Tagawa et al.), and U.S. Patent No. 8,783,179 (Kurokawa et al.). It is particularly useful to carry out the first anodization process using phosphoric acid.

[0038] The obtained outer aluminum oxide layer has a plurality of outer pores having an average outer pore diameter (D o ) of at least 12 nm or at least 15 nm and 30 nm or less, or even 50 nm or less. Further, the average dry thickness (T o) can be at least 20 nm or at least 50 nm or at least 130 nm or even at least 150 nm, and can be 300 nm or less or 400 nm or less or 650 nm or less. In some embodiments, the pore density (C o ) of the outer anodic oxidation layer is generally at least 500 pores / μm 2 ~3,000 pores / μm 2 or less.

[0039] Furthermore, in some embodiments, the average outer pore diameter (D o ) in nanometers of the outer aluminum oxide layer and the pore density (C 2 ) in pores / μm units can be further constrained or related according to each of the following equations: o ) can be further constrained or related according to each of the following equations: 0.3 ≤ P o ≤ 0.8 or 0.3 ≤ P o ≤ 0.6 (where the porosity P o is as defined above).

[0040] After the first anodization process has been carried out for a desired time, the formed outer aluminum oxide layer can be rinsed, if desired, in a suitable solution such as water at a suitable temperature and time in step C) to remove residual acid and aluminum and stop the first anodization process.

[0041] Although it is common when the first anodization process is carried out in sulfuric acid, the average outer pore diameter (D o) In some embodiments where it becomes smaller than the previously specified value, after the first anodization process and optionally the rinsing process, a pore widening process can be added. The pore widening process can be carried out in an acidic solution or a basic solution. Details regarding the pore widening process can be found in all the previously specified known techniques, such as the specifications of U.S. Patent No. 9,259,954, U.S. Patent No. 8,978,555, U.S. Patent No. 8,789,464, and U.S. Patent No. 8,783,179. After such a pore widening process, another rinsing step can be carried out using an appropriate solution such as water to remove the acidic or basic components used in the pore widening process.

[0042] Then, an additional anodization process of step D) is carried out using an appropriate electrolyte composition that can contain at least 100 g / l to 350 g / l or less of sulfuric acid and an appropriate amount of aluminum ions, such as 5 g / l, and an inner aluminum oxide layer is formed under the outer aluminum oxide layer. These solution amounts can be optimized with respect to acid concentration, aluminum ion concentration, residence time, and temperature to obtain the desired inner aluminum oxide layer characteristics described herein. Details of such a second anodization process are shown in the examples described below. This additional anodization process is often the "second" and final anodization process, but in some embodiments, this additional anodization process is the third and final anodization process used to form an inner aluminum oxide layer under an intermediate aluminum oxide layer (described later).

[0043] The obtained inner aluminum oxide layer disposed on the granulated and etched surface of the substrate has a number of inner pores with an average inner pore diameter (D i ) of 11 nm or less. In such embodiments, the ratio of D o to D i can be greater than 1.1:1 and further can be greater than 1.5:1. Further, the average dry thickness (T i) can be at least 300 nm or at least 500 nm and can be 1500 nm or less or 3,000 nm or less.

[0044] In some embodiments, the outer aluminum oxide layer is disposed directly on the inner aluminum oxide layer, and the average dry thickness (T o ) of the outer aluminum oxide layer is at least 50 nm, the average inner pore diameter (D i ) is 11 nm or less, the average dry thickness (T i ) of the inner aluminum oxide layer is at least 500 nm, and the average inner pore diameter (D i ) is smaller than the average outer pore diameter (D o ).

[0045] After the second anodization process has been carried out for a desired time, both the formed outer aluminum oxide layer and the inner aluminum oxide layer can, if desired, be rinsed in a suitable solution, such as water, at a suitable temperature and for a suitable time to remove residual acid and aluminum salts, and the second anodization process can be stopped.

[0046] In some embodiments of the present invention, the aluminum-containing support is subjected to a second (but not final) anodization process (process C')) between process C) and process D) using a suitable acid or a mixture thereof at a suitable time and a suitable temperature to provide an intermediate aluminum oxide layer under the outer aluminum oxide layer. This second anodization process is carried out after the first anodization process and before the third anodization process to form the intermediate aluminum oxide layer. Thus, the intermediate aluminum oxide layer is generally formed between the outer aluminum oxide layer and the inner aluminum oxide layer formed later. In such embodiments, the formed intermediate aluminum oxide layer can have an average dry thickness (T m ) of at least 60 nm to 300 nm or less and can include a number of intermediate pores having an average intermediate pore diameter (D m ) of at least 20 nm to 60 nm or less.

[0047] In such an embodiment, D m is larger than D o , D o is larger than D i , T o can be less than 150 nm, and the average dry thickness (T o ) of the outer aluminum oxide layer is less than 150 nm.

[0048] After the formation of this intermediate aluminum oxide layer, the outer aluminum oxide layer and the intermediate aluminum oxide layer can be rinsed as described above only for the outer aluminum oxide layer in step C”) before the inner aluminum oxide layer is formed as described above.

[0049] According to the present invention, in step F), it is essential to provide a hydrophilic layer so as to be disposed on the outer aluminum oxide layer. The hydrophilic layer is one or more phosphorus-containing compounds (1) having a C1 dry coating amount, which is represented by the following formula (I), and optionally one or more hydrophilic polymers (2) having a C2 dry coating amount. It can be provided from a hydrophilic layer composition containing.

[0050] The hydrophilic layer has a total dry coating amount of at least 50 mg / m 2 ~500 mg / m 2 or less. Generally, since the hydrophilic layer is directly disposed on the outer aluminum oxide layer, there is no intermediate layer. Since the outer aluminum oxide layer contains pores, a part of the hydrophilic layer can be present inside such outer pores and in the pores under the outer aluminum oxide layer.

[0051] When both (1) and (2) are present, the ratio of the C1 dry coating amount to the C2 dry coating amount is at least 11:9, and this ratio can be 10:1 or less or 30:1 or less. Generally, the hydrophilic layer is applied or disposed on the outer aluminum oxide layer to give the dry coating amount of the hydrophilic layer. The C1 dry coating amount can be at least 50 mg / m 2 or at least 75 mg / m 2 , and can be 200 mg / m 2 or less or 300 mg / m2 It may be as follows. The C2 dry coating amount is 0 or 200 mg / m 2 or less or 100 mg / m 2 or less or 50 mg / m 2 or less and may be as follows.

[0052] One or more phosphorus-containing compounds (1) essential for the hydrophilic layer are represented by the following formula (I):

Chemical formula

[0053] Furthermore, the -OM group is selected such that when one or more phosphorus-containing compounds (1) represented by formula (I) are dissolved in an aqueous solution containing 5% by weight of one or more phosphorus-containing compounds (1) represented by formula (I), the one or more phosphorus-containing compounds (1) of formula (I) exhibit a pH of at least 1 to 10 or at least 1 to 8, either alone or in a mixture of the compounds. When two or more phosphorus-containing compounds are used, the mixture of these two or more phosphorus-containing compounds is also selected to meet this pH requirement.

[0054] The compound represented by formula (I) can be obtained from various commercial sources or can be synthesized by those skilled in the art using known starting materials and synthetic procedures.

[0055] The hydrophilic layer used in the practice of the present invention is optionally but preferably contains one or more hydrophilic polymers (2) in the C2 dry coating amount defined above. By "hydrophilic" with respect to these polymers is meant that these polymers have a solubility of at least 1% in water at 25°C.

[0056] More specifically, at least one of the one or more hydrophilic polymers (2) contains a pendant carboxylic acid group, phosphonic acid group, or phosphate group, salts of these groups (carboxylates, phosphonates, and phosphates), or a combination of two or more of these pendant acidic groups (or their salts). These acid groups and bases contribute to the water solubility of the hydrophilic polymer and thus to the adhesion of these hydrophilic polymers to the anodized aluminum surface. Therefore, these acid groups and bases can be considered surface-bound hydrophilic groups. The hydrophilic polymer can contain, in addition to the surface-bound hydrophilic groups, non-surface-bound hydrophilic groups that mainly contribute to the water solubility of the hydrophilic polymer. Useful non-surface-bound hydrophilic groups include, but are not limited to, amide groups, hydroxyl groups, sulfonate groups, and polyethylene oxide groups.

[0057] One or more hydrophilic polymers (2) can be synthesized by condensation polymerization or addition polymerization using monomers having surface-bonded hydrophilic groups and non-surface-bonded hydrophilic groups. The addition polymerization of suitable ethylenically unsaturated polymerizable monomers can be initiated using free radical initiators, cationic initiators, and anionic initiators. The surface-bonded hydrophilic groups and non-surface-bonded hydrophilic groups on these hydrophilic polymers can be introduced by the polymerization of monomers having these groups, or can be formed by the reaction of a suitable precursor polymer having pendant precursor groups that can be converted to surface-bonded hydrophilic groups and non-surface-bonded hydrophilic groups. Among the various synthetic techniques for preparing one or more hydrophilic polymers (2) of the present invention, the free radical addition polymerization of a monomer composition containing an ethylenically unsaturated polymerizable monomer having a surface-bonded hydrophilic group and optionally an ethylenically unsaturated polymerizable monomer having a non-surface-bonded hydrophilic group is particularly useful.

[0058] Examples of useful ethylenically unsaturated polymerizable monomers having surface-bonded hydrophilic groups include, but are not limited to, acrylic acid, methacrylic acid, itaconic acid, maleic acid, vinylphosphonic acid, acryloyloxyethyl phosphate, methacryloyloxyethyl phosphate, polyethylene glycol acrylate phosphate, and polyethylene glycol methacrylate phosphate.

[0059] Examples of useful ethylenically unsaturated polymerizable monomers having non-surface-bonded hydrophilic groups include, but are not limited to, methacrylamide, acrylamide, N,N-dimethylacrylamide, N-hydroxyethylmethacrylamide, N-(methoxymethyl)acrylamide, hydroxyethyl acrylate, hydroxyethyl methacrylate, N-vinylpyrrolidone, sodium p-styrenesulfonate, sodium acrylamidopropylsulfonate, and polyethylene glycol methyl ether methacrylate. Mixtures of two or more of these monomers can be used to provide various repeating units. Among the monomers having non-surface-bonded hydrophilic groups, those having at least one amide group, such as acrylamide or methacrylamide, are particularly useful. In some embodiments, the repeating units derived from the monomer having an amide group can constitute up to 95 mol% of the total amount of repeating units in the hydrophilic polymer, and the repeating units derived from a monomer having one or more of a hydrophilic surface-bonded group, such as a carboxylic acid group, carboxylate, or carboxylate salt, can constitute 50 mol% or less, typically 40 mol% or less, or 30 mol% or less of the total amount of repeating units in the hydrophilic polymer.

[0060] Thus, in some embodiments where one or more hydrophilic polymers (2) are present in the hydrophilic layer, the one or more hydrophilic polymers (2) include a hydrophilic polymer comprising repeating units containing a carboxylic acid, phosphonic acid, phosphate group, or a salt or ester of any of these acids, and optionally, repeating units containing an amide group.

[0061] When mixtures of one or more hydrophilic polymers (2) are present, they can have different repeating unit compositions and / or different amounts of repeating units.

[0062] In addition to one or more phosphorus-containing compounds (1) with or without one or more hydrophilic polymers (2), the hydrophilic layer can include one or more surfactants, leveling agents, chelating agents, and biocides.

[0063] The process used to form the hydrophilic layer can be carried out in any suitable manner, such as described in paragraphs

[0058] to

[0061] of U.S. Patent Application Publication No. 2014 / 0047993 (supra). A particularly useful technique for forming the hydrophilic layer is to directly coat an appropriate solvent solution, such as an aqueous solution, of the desired amount of the hydrophilic layer formulation onto the outer aluminum oxide layer and then dry the resulting wet coating.

[0064] After all these essential processes, the resulting aluminum-containing substrate of the present invention is ready for the production of a lithographic printing plate precursor according to the present invention in any suitable form, such as in the form of a flat sheet or a continuous web or coil.

[0065] Infrared-sensitive image-forming layer and precursor Generally, one on-press-developable negative-type infrared-sensitive image-forming layer can be formed or disposed in a suitable manner on the hydrophilic layer of the aluminum-containing substrate of the present invention using an appropriate on-press-developable negative-type infrared-sensitive image-forming layer formulation, as described in more detail below.

[0066] Negative-type lithographic printing plate precursor: The original plate of the present invention can be formed by appropriately applying an in-flight developable negative-type infrared-sensitive composition as described below to a suitable aluminum-containing substrate of the present invention (as described above) to form an in-flight developable negative-type infrared-sensitive image-forming layer on this substrate. Generally, an in-flight developable negative-type infrared-sensitive composition (and the resulting in-flight developable negative-type infrared-sensitive image-forming layer) contains (a) one or more free-radical polymerizable components, (b) an initiator composition that gives free radicals when exposed to image-forming radiation (e.g., infrared rays as defined herein), and (c) an infrared absorber containing an anionic chromophore having a net negative charge or acidic group as essential components, and optionally contains a polymer binder different from all of (a), (b), and (c). All of these essential and optional components are described in more detail below. The in-flight developable negative-type infrared-sensitive image-forming layer is generally the outermost layer of the original plate, but in some embodiments, there may be an outermost overcoat (also known as a top coat or oxygen barrier layer, described below) disposed thereon as the outermost layer.

[0067] An in-flight developable negative-type infrared-sensitive composition (and the in-flight developable negative-type infrared-sensitive image-forming layer produced from the composition) contains one or more free-radical polymerizable components (a), each of which contains one or more free-radical polymerizable groups (two or more such groups in some embodiments) that can polymerize using free-radical initiation. In some embodiments, the in-flight developable negative-type infrared-sensitive image-forming layer contains two or more free-radical polymerizable components having the same or different numbers of free-radical polymerizable groups in each molecule.

[0068] Useful free-radical polymerizable components may contain one or more free-radical polymerizable monomers or oligomers having one or more addition-polymerizable ethylenically unsaturated groups (e.g., two or more such groups). Similarly, crosslinkable polymers having such free-radical polymerizable groups may also be used. Oligomers or prepolymers such as urethane acrylates and methacrylates, epoxide acrylates and methacrylates, polyester acrylates and methacrylates, polyether acrylates and methacrylates, and unsaturated polyester resins may be used. In some embodiments, the free-radical polymerizable component contains a carboxyl group.

[0069] One or more free-radical polymerizable components have a molecular weight large enough to improve the mechanical properties of the on-press developable negative infrared-sensitive image-forming layer, whereby the corresponding lithographic printing plate precursor can be made suitable for transport in typical packaging and handling during normal pre-printing operations.

[0070] Numerous other free-radical polymerizable components are known in the art and are described in a number of documents including paragraphs

[0170] of European Patent No. 1,182,033 A1 (Fujimaki et al.), as well as U.S. Patent No. 6,309,792 (Hauck et al.), U.S. Patent No. 6,569,603 (Furukawa), and U.S. Patent No. 6,893,797 (Munnelly et al.), and U.S. Patent Application Publication No. 2009 / 0142695 (Baumann et al.).

[0071] One or more free-radical polymerizable components (a) are generally present in the on-press developable negative infrared-sensitive image-forming layer in an amount of at least 10% by weight or at least 20% by weight, and 50% by weight or less or 70% by weight or less, based on the total dry weight of the on-press developable negative infrared-sensitive image-forming layer.

[0072] The in-flight developable negative infrared-sensitive image-forming layer used in the present invention may also contain an initiator composition (b), which, in the presence of a suitable infrared absorber, gives free radicals when the in-flight developable negative infrared-sensitive image-forming layer is exposed to suitable image-forming infrared rays, and initiates the polymerization of one or more free-radical polymerizable components.

[0073] Examples of the initiator composition useful for the infrared-sensitive composition and the image-forming layer include, but are not limited to, the onium salts described in detail in

[0131] of US Patent Application Publication No. 2014 / 0047993 (supra), such as ammonium, iodonium, sulfonium, and phosphonium compounds. Examples of onium salts include triarylsulfonium, diaryliodonium, and diaryldiazonium, where the aryl group includes a phenyl group and a naphthyl group, and the aryl group may be substituted.

[0074] The onium salt can be obtained by combining an onium salt having sulfonium or iodonium in the molecule with an onium salt in the molecule. The onium salt can be a polyvalent onium salt having at least two onium ion atoms bonded by a covalent bond in the molecule. Among polyvalent onium salts, those having at least two onium ion atoms in the molecule are useful, and those having a sulfonium or iodonium cation in the molecule are particularly useful. Representative polyvalent onium salts are represented by the following formulas (6) and (7). [Chemical formula]

[0075] Also, the onium salts described in paragraphs

[0033] to

[0038] of JP-A No. 2002-082429 [or US Patent Application Publication No. 2002-0051934 (Ippei et al.)] and the iodonium borate complex described in US Patent No. 7,524,614 (supra) can also be used.

[0076] Anions useful for iodonium salts include ClO4 - , PF6 - , BF4 - , SbF6 - , CH3SO3 - , CF3SO3 - , C6H5SO3 - , CH3C6H4SO3 - , HOC6H4SO3 - , ClC6H4SO3 - , and the following structure (VII): B - (R 1 )(R 2 )(R 3 )(R 4 ) (VII) Examples include, but are not limited to, borate anions represented by the formula, where R 1 , R 2 , R 3 , and R 4 are each independently a substituted or unsubstituted alkyl, a substituted or unsubstituted aryl (including halogen-substituted aryl groups), a substituted or unsubstituted alkenyl, a substituted or unsubstituted alkynyl, a substituted or unsubstituted cycloalkyl, or a substituted or unsubstituted heterocyclic group, or two or more of R 1 , R 2 , R 3 , and R 4 can be joined together to form a substituted or unsubstituted heterocycle with the boron atom, such a ring having up to 7 carbon atoms, nitrogen atoms, oxygen atoms, or nitrogen atoms. In some embodiments, R 1 , R 2 , R 3 , and R 4All are the same or different substituted or unsubstituted aryl groups, such as substituted or unsubstituted phenyl groups, or it is more likely that all of these groups are unsubstituted phenyl groups. In many embodiments, at least one of X1, X2, and X3 is a tetraarylborate anion containing the same or different aryl groups, or in particularly useful embodiments, one or more are tetraphenylborate anions, or each of X1, X2, and X3 is a tetraphenylborate anion.

[0077] The initiator composition is generally present in the on-machine developable negative infrared-sensitive image-forming layer in an amount of at least 0.5% by weight or at least 2% by weight or even at least 4% by weight and 12% by weight or less or 15% by weight or less or 20% by weight or less, sufficient to provide one or more polymerization initiators with respect to the total dry weight of all the on-machine developable negative infrared-sensitive image-forming layers.

[0078] In addition, the on-machine developable infrared-sensitive image-forming layer also contains one or more infrared absorbers (c), each containing an anionic chromophore having a net negative charge or an acidic group, thereby providing the desired infrared sensitivity when an image is formed in response to digital information using a suitable image-forming apparatus (e.g., an infrared radiation laser). In other words, among these one or more infrared absorbers, there is none having a cationic chromophore having a net positive charge and no acidic group, and among these one or more infrared absorbers, there is none having a net zero charge and no acidic group.

[0079] Each of the one or more infrared absorbers (c) may further contain one or more suitable counterions for the anionic chromophore, which will be readily apparent to those skilled in the art.

[0080] One or more suitable infrared absorbers can be infrared absorbing dyes having an anionic chromophore with a net negative charge, which is essential, but these infrared absorbers are known in the art and examples include those described in U.S. Patent No. 6,511,782 (Vermeersch et al.), U.S. Patent No. 5,208,135 (Patel et al.), U.S. Patent No. 7,368,215 (Munnelly et al.), U.S. Patent No. 8,409,780 (Callant et al.), and U.S. Patent No. 8,778,590 (Callant), but are not limited thereto.

[0081] Among one or more infrared absorbers (c) according to the present invention, particularly useful classes are those of the following formula (II):

Chemical formula

[0082] In some embodiments, R 1 , R 2 , and R 3 It is desirable that at least one of them contains a carboxylate group to impart a net negative charge or an acidic group to formula (II).

[0083] The net negative charge of the anionic chromophore represented by formula (II) is balanced by the cation Z + and can form a neutral infrared absorber. Suitable cations Z + include M described in formula (I) + and the cations of the onium salts described above for the initiator composition (b), such as diaryliodonium salts.

[0084] Specific examples of useful anionic infrared absorbers (AIR) having a chromophore represented by formula (II) are shown below.

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0085] The total dry coating amount of one or more infrared absorbers (c) in the in-air-developable negative-type infrared-sensitive image-forming layer is at least 5 mg / m 2 or at least 10 mg / m 2 and is 100 mg / m 2 or less or 200 mg / m 2 or less.

[0086] In many embodiments, it is optionally desirable for the in-air-developable negative-type infrared-sensitive image-forming layer to further comprise one or more polymer binders (d) (or materials acting as polymer binders) for all of the materials in the above layers. Such polymer binders are different from all of the materials of (a), (b), and (c) described above. These polymer binders are generally non-crosslinkable and non-polymerizable, and at least one of these polymer binders can be in particulate form.

[0087] Such polymer binders (d) can be selected from many polymer binder materials known in the art, including polymers containing repeating units having side chains containing polyalkylene oxide segments, such as those described in U.S. Patent No. 6,899,994 (Huang et al.). Other useful polymer binders (d) contain two or more repeating units having different side chains containing polyalkylene oxide segments, as described, for example, in International Publication No. 2015-156065 (Kamiya et al.). Some of such polymer binders (d) can further contain repeating units having pendant cyano groups, as described, for example, in U.S. Patent No. 7,261,998 (Hayashi et al.).

[0088] Some useful polymer binders (d) can exist in particulate form, i.e., in the form of discrete, non-aggregated particles. Such discrete particles can have an average particle size of at least 10 nm to 1500 nm or less, or typically at least 80 nm to 600 nm or less, and are generally uniformly distributed in a on-machine developable negative infrared-sensitive image-forming layer. For example, one or more useful polymer binders (d) can exist in the form of particles having an average particle size of at least 50 nm to 400 nm or less. The average particle size can be determined by various known methods, including measurement of the particles in an electron scanning microscope image and averaging a set number of measurements.

[0089] The polymer binder (d) can also have a backbone containing a plurality (at least two) of urethane moieties and a pendant group containing a polyalkylene oxide segment.

[0090] Other useful polymer binders (d) can contain polymerizable groups such as acrylate esters, methacrylate esters, vinyl aryls, and allyl groups, and alkali-soluble groups such as carboxylic acids. Some of these useful polymer binders (d) are described in U.S. Patent Application Publication No. 2015 / 0099229 (Simpson et al.) and U.S. Patent No. 6,916,595 (Fujimaki et al.).

[0091] Useful polymer binders (d) generally have a weight average molecular weight (Mw) determined by gel permeation chromatography (polystyrene standard) of at least 2,000 to 500,000 or less, or at least 20,000 to 300,000 or less.

[0092] The total amount of the polymer binder (d) can be present in the on-machine developable negative infrared-sensitive image-forming layer in an amount of at least 10 wt% or at least 20 wt%, and 50 wt% or less or 70 wt% or less based on the total dry weight of the on-machine developable negative infrared-sensitive image-forming layer.

[0093] Other polymer materials known in the art (different from the polymer binder (d)) may be present in the on-board developable negative infrared-sensitive image-forming layer, and such polymer materials are generally more hydrophilic or hydrophobic than the above-mentioned polymer binder (d). Examples of such hydrophilic polymer binders include, but are not limited to, cellulose derivatives such as hydroxypropyl cellulose, carboxymethyl cellulose, and polyvinyl alcohol having various degrees of saponification. More hydrophobic polymer binders have lower developability than the above-mentioned polymer binder (d) and typically have an acid value of less than 20 mgKOH / g for all acidic groups with a pKa less than 7 and their corresponding salts.

[0094] Additives optionally added to the on-board developable negative infrared-sensitive image-forming layer may include organic dyes or organic dye precursors known in the art and color developers. Such optionally added additives can be used as printing output colorants and may be present in an amount of at least 1 wt% to 10 wt% or less based on the total dry weight of the on-board developable negative infrared-sensitive image-forming layer.

[0095] Other useful printing output colorants are known in the art and include, for example, azo dyes, triarylmethane dyes, cyanine dyes, and spiro lactone or spiro lactam colorants as described in U.S. Patent Application Publication No. 2009 / 0047599 (Horne et al.), and various printing output chemicals described in U.S. Patent Application Publication No. 2021 / 0078350 (Viehmann et al.), U.S. Patent Application Publication No. 2021 / 0302834 (Viehmann et al.), and U.S. Patent Application No. 17 / 685,570 (filed on March 3, 2022 by Simpson et al.), U.S. Patent Application No. 17 / 685,592 (filed on March 3, 2002 by Simpson et al.), and U.S. Patent Application No. 17 / 720,405 (filed on April 14, 2022 by Hansmann et al.).

[0096] The on-machine developable negative-type infrared-sensitive image-forming layer may contain crosslinked polymer particles having an average particle size of at least 2 μm or at least 4 μm and 20 μm or less, as described, for example, in U.S. Patent No. 8,383,319 (Huang et al.), U.S. Patent No. 8,105,751 (Endo et al.), and U.S. Patent No. 9,366,962 (Kamiya et al.).

[0097] Overcoat: In many embodiments of the lithographic printing plate precursor of the present invention, the on-machine developable negative-type radiation-sensitive image-forming layer is the outermost layer with no layer disposed on its surface. However, the precursor of the present invention can be designed by disposing a layer (also known in the art as an overcoat or topcoat) on the on-machine developable negative-type infrared-sensitive image-forming layer (or directly on the layer, without disposing an intermediate layer between these two layers). This overcoat, if present, is generally the outermost layer of the precursor and can be hydrophilic or hydrophobic.

[0098] The overcoat may contain one or more film-forming water-soluble polymer binders in an amount of at least 60% by weight to 100% by weight or less based on the total dry weight of the hydrophilic overcoat. The film-forming water-soluble (i.e., hydrophilic) polymer binder may contain modified or unmodified poly(vinyl alcohol) having a saponification degree of at least 30% or at least 75% or at least 90% and 99.9% or less.

[0099] The overcoat can be provided with a dry coating coverage of at least 0.1 g / m 2 or at least 0.15 g / m 2 and 2.5 g / m 2 or less but less than 4 g / m 2 In some embodiments, the dry coating coverage is 0.1 g / m 2 ~1.5 g / m 2 or less, or at least 0.1 g / m 2 ~0.9 g / m 2It is small as follows, and as a result, the overcoat becomes relatively thin.

[0100] Manufacture of the original plate for lithographic printing The original plate for lithographic printing of the present invention can be provided in the following manner. The on-machine developable negative-type infrared-sensitive image-forming layer composition containing the above-described materials can be applied to the aluminum-containing substrate of the present invention, usually in the form of a continuous substrate roll or web as described above, using any suitable apparatus and procedure, such as spin coating, knife coating, gravure coating, die coating, slot coating, bar coating, wire rod coating, roller coating, or extrusion hopper coating. The on-machine developable negative-type infrared-sensitive image-forming layer composition can also be applied by spraying onto a suitable aluminum-containing substrate of the present invention. Typically, when this composition is applied in an appropriate wet coating amount, the composition is dried in a suitable manner known in the art to provide the desired dry coating amount as described below, thereby providing an infrared-sensitive continuous article. This article can be in any suitable form, such as in the form of a web, that can be used to manufacture individual original plates using known manufacturing processes.

[0101] The manufacturing method typically includes mixing various components required for the chemical reaction of a specific on-machine developable negative-type infrared-sensitive image-forming layer in a suitable organic solvent or a mixture thereof, and removing one or more solvents by evaporation under suitable drying conditions.

[0102] After appropriate drying, the dry coating amount of the on-machine developable negative-type infrared-sensitive image-forming layer on the substrate of the present invention is generally at least 0.1 g / m 2 or at least 0.4 g / m 2 and is 2 g / m 2 or less or 4 g / m 2 or less, but other dry coating amounts can be used if desired.

[0103] Under actual manufacturing conditions, the results of these coating operations are a continuous web or roll of an infrared-sensitive lithographic printing plate original material having an on-press-developable negative-type infrared-sensitive image-forming layer and any layer that may be present in any of the above cases on the aluminum-containing substrate of the present invention.

[0104] Image formation (exposure) conditions In use, the lithographic printing plate original of the present invention can be exposed on-press to a suitable infrared light source for exposure according to the infrared absorber present in the on-press-developable negative-type infrared-sensitive image-forming layer. For example, the lithographic printing plate original can be imaged with an infrared laser that emits a significant amount of radiation in the range of at least 750 nm to 1400 nm or less, or at least 800 nm to 1250 nm or less. The result of this imagewise exposure is that exposed and unexposed areas are produced in the exposed on-press-developable negative-type infrared-sensitive image-forming layer.

[0105] Image formation can be carried out using image-forming infrared light or exposure infrared light from an infrared generating laser (or an array of such lasers). Image formation can also be carried out using image-forming infrared light of a plurality of wavelengths simultaneously if desired. The laser used to expose the original of the present invention is usually a diode laser due to the reliability and low maintenance of diode laser systems, but other lasers, such as gas or solid lasers, can also be used. The combination of output, intensity, and exposure time for infrared image formation will be readily apparent to those skilled in the art.

[0106] The image-forming energy of the infrared light is at least 30 mJ / cm 2 ~500 mJ / cm 2 hereinafter, typically at least 50 mJ / cm 2 ~300 mJ / cm 2 hereinafter and can be less.

[0107] Processing (development) and printing After imagewise exposure, an exposed original plate having exposed and unexposed areas in a on-press developable radiation-sensitive image-forming layer is processed on press in a suitable manner, the unexposed areas and, if an overcoat is present, the overcoat are removed, and the hardened exposed areas can be left intact.

[0108] For example, the original plate of the present invention is on-press developable using lithographic ink, dampening water, or a combination of lithographic ink and dampening water. In such an embodiment, an imagewise exposed on-press developable negative-type infrared-sensitive lithographic printing plate original according to the present invention can be attached to a printing press, and then the printing operation is started. The unexposed areas in the on-press developable negative-type infrared-sensitive image-forming layer are removed by suitable dampening water, lithographic ink, or a combination of both when the first printed image is made.

[0109] At the start of a typical printing press by a sheet-fed printing press, first the dampening roller is engaged to supply dampening water to the attached imagewise exposed original plate to swell the exposed on-press developable negative-type infrared-sensitive image-forming layer at least in the unexposed areas. After rotating several times, the inking roller is engaged to supply one or more lithographic inks so as to cover the entire printing surface of the lithographic printing plate. Typically, within 5 to 20 rotations after the engagement of the inking roller, printing paper is supplied, and using the formed ink-dampening water emulsion, the unexposed areas of the on-press developable negative-type infrared-sensitive image-forming layer are removed from the lithographic printing plate, and if material is present on the blanket cylinder, the material is removed.

[0110] The present invention provides at least the following embodiments, individually or in any suitable combination.

[0111] 1. A lithographic printing plate original comprising an aluminum-containing substrate having a hydrophilic surface, and a on-press developable negative-type infrared-sensitive image-forming layer disposed on the hydrophilic surface of the aluminum-containing substrate, wherein the aluminum-containing substrate An aluminum-containing plate having a granulated and etched surface, An inner aluminum oxide layer disposed on the granulated and etched surface, having an average dry thickness (T i ) of at least 300 nm to 3000 nm or less, and containing a large number of inner pores with an average inner pore diameter (D i ) of 11 nm or less and containing aluminum sulfate, the inner aluminum oxide layer, An outer aluminum oxide layer disposed on the inner aluminum oxide layer, containing a large number of outer pores with an average outer pore diameter (D o ) of at least 12 nm to 50 nm or less, and having an average dry thickness (T o ) of at least 20 nm to 650 nm or less, the outer aluminum oxide layer, and A hydrophilic layer disposed on the outer aluminum oxide layer, The hydrophilic layer is (1) having a C1 dry coating amount and one or more phosphorus-containing compounds represented by the following formula (I):

Chemical formula

[0112] 2. The lithographic printing plate original according to Embodiment 1, wherein the dry coating amount of C1 is at least 75 mg / m 2 ~200 mg / m 2 or less.

[0113] 3. The lithographic printing plate original according to Embodiment 1 or 2, wherein the ratio of the dry coating amount of C1 to the dry coating amount of C2 is at least 11:9 to 30:1 or less, and one or more hydrophilic polymers (2) are present in the hydrophilic layer.

[0114] 4. The lithographic printing plate original according to any one of Embodiments 1 to 3, wherein one or more infrared absorbers (c) are present in the negative-type infrared-sensitive image-forming layer capable of on-machine development with a dry coating amount of at least 5 mg / m 2 ~200 mg / m 2 or less.

[0115] 5. The lithographic printing plate original according to any one of Embodiments 1 to 4, wherein one or more hydrophilic polymers (2) are present in the hydrophilic layer, and one or more hydrophilic polymers (2) include a hydrophilic polymer containing a repeating unit containing a carboxylic acid, a phosphonic acid, a phosphate group, or a salt or ester of any of these acids, and optionally a repeating unit containing an amide group.

[0116] 6. M +is independently selected from the group consisting of a proton, a sodium cation, a potassium cation, an ammonium cation, an alkylammonium cation, a dialkylammonium cation, a trialkylammonium cation, and a tetraalkylammonium cation, and each alkyl group is optionally substituted, the lithographic printing plate original according to any one of Embodiments 1 to 5.

[0117] 7. When dissolved in an aqueous solution containing 5% by weight of one or more phosphorus-containing compounds (1) represented by formula (I), the -OM group is selected so that the one or more phosphorus-containing compounds (1) represented by formula (I) exhibit a pH of at least 1 to 10 or less, the lithographic printing plate original according to any one of Embodiments 1 to 6.

[0118] 8. An anionic chromophore having a net negative charge or an acidic group is represented by the following formula (II) [Chemical formula] (wherein each X independently represents >S, >O, >NR, or >C(R)2, each R 1 is independently an optionally substituted alkyl group, R 2 represents hydrogen, halogen, -SR, -SO2R, -OR, or -NR2 group, each R 3 is independently a hydrogen atom, an optionally substituted alkyl group, -COO - -COOR, -OR, -SR, -NR2, a halogen atom, a sulfonate group, or an optionally substituted benzo-fused ring, --- represents an optionally present carbocyclic 5-membered or 6-membered ring, each R independently represents hydrogen, an optionally substituted alkyl group, or an optionally substituted aryl group, each n is independently 0, 1, 2, or 3, R 1 R 2 and R 3At least one of them contains a sulfonate group, a carboxylate group, or both a sulfonate group and a carboxylate group in order to give a net negative charge or an acidic group to formula (II). The original printing plate for lithography according to any one of Embodiments 1 to 7, represented by

[0119] 9.R 1 , R 2 and R 3 The original printing plate for lithography according to Embodiment 8, wherein at least one of them contains a carboxylate group in order to give a net negative charge or an acidic group to formula (II).

[0120] 10. The outer aluminum oxide layer has an average dry thickness (T o ) of at least 50 nm, the outer aluminum oxide layer is directly disposed on the inner aluminum oxide layer, and the average dry thickness (T i ) of the inner aluminum oxide layer is at least 500 nm, the average inner pore diameter (D i ) is 11 nm or less, and is smaller than the average outer pore diameter (D o ). The original printing plate for lithography according to any one of Embodiments 1 to 9.

[0121] 11. The aluminum-containing substrate further includes an intermediate aluminum oxide layer disposed between the inner aluminum oxide layer and the outer aluminum oxide layer. The intermediate aluminum oxide layer has an average dry thickness (T m ) of at least 60 nm to 300 nm or less, and includes a large number of intermediate pores having an average intermediate pore diameter (D m ) of at least 20 nm to 60 nm or less. D m is larger than D o , D o is larger than D i , and the average dry thickness (T o ) of the outer aluminum oxide layer is less than 150 nm. The original printing plate for lithography according to any one of Embodiments 1 to 10.

[0122] 12. The original lithographic printing plate according to any one of Embodiments 1 to 11, wherein the on-machine developable negative infrared-sensitive layer further contains one or more polymer binders (d), and at least one of them is in particulate form.

[0123] 13. The original lithographic printing plate according to any one of Embodiments 1 to 12, wherein the on-machine developable negative infrared-sensitive image-forming layer is the outermost layer.

[0124] 14. The original lithographic printing plate according to any one of Embodiments 1 to 13, which contains one or more hydrophilic polymers (2), and a hydrophilic polymer containing a repeating unit containing one or more of a carboxylic acid group, a carboxylate, or a carboxylate group in an amount of at least 50 mol% of all the repeating units.

[0125] 15. The original lithographic printing plate according to any one of Embodiments 1 to 14, which contains one or more hydrophilic polymers (2), and a hydrophilic polymer containing a repeating unit containing a carboxylic acid, a phosphonic acid, or a phosphate group and a repeating unit containing an amide group.

[0126] 16. A method for providing a lithographic printing plate, comprising: imagewise exposing the original lithographic printing plate according to any one of Embodiments 1 to 15 to image-forming infrared rays to form an imagewise infrared-exposed image-forming layer having exposed areas and unexposed areas, and using a lithographic printing ink, dampening water, or both a lithographic printing ink and dampening water to remove the unexposed areas from the imagewise infrared-exposed image-forming layer on the machine to form a lithographic printing plate The method includes.

[0127] 17. A method for manufacturing the original lithographic printing plate according to any one of Embodiments 1 to 15, comprising: A) providing an aluminum-containing plate having an electrochemically or mechanically granulated and etched surface, B) Subjecting the aluminum-containing plate to a first anodization process to form an outer aluminum oxide layer on an electrochemically or mechanically granulated and etched surface, wherein the outer aluminum oxide layer contains a plurality of outer pores with an average outer pore diameter (D o ) of at least 12 nm to 50 nm or less, and has an average dry thickness (T o ) of at least 20 nm to 650 nm or less, the step of subjecting to the first anodization process, C) The step of rinsing the outer aluminum oxide layer, D) Subjecting the aluminum-containing plate to an additional anodization process using sulfuric acid to form an inner aluminum oxide layer under the outer aluminum oxide layer, wherein the inner aluminum oxide layer has an average dry thickness (T i ) of at least 300 nm to 3000 nm or less, contains a plurality of inner pores with an average inner pore diameter (D i ) of 11 nm or less, and the inner aluminum oxide layer contains aluminum sulfate, the step of subjecting to the additional anodization process, E) The step of rinsing the outer aluminum oxide layer and the inner aluminum oxide layer, F) The step of providing a hydrophilic layer on the outer aluminum oxide layer, wherein the hydrophilic layer (1) has a C1 dry coating amount and one or more phosphorus-containing compounds represented by the following formula (I):

Chemical formula

[0128] 18. The method according to embodiment 17, wherein the first anodization process is carried out using phosphoric acid.

[0129] 19. Between step C) and step D), C’) A step of subjecting the aluminum-containing plate to a second anodization process to form an intermediate aluminum oxide layer under the outer aluminum oxide layer, wherein the intermediate aluminum oxide layer has an average dry thickness (T m ) of at least 60 nm to 300 nm or less, contains a large number of intermediate pores having an average intermediate pore diameter (D m ) of at least 20 nm to 60 nm or less, D m is larger than D o , D o is larger than D i , and the average dry thickness (T o ) of the outer aluminum oxide layer is less than 150 nm, a step of subjecting to a second anodization process, and Step of rinsing the outer aluminum oxide layer and the intermediate aluminum oxide layer with C further comprising The additional anodization process of step D) is a third anodization process for forming an inner aluminum oxide layer under the intermediate aluminum oxide layer, The method according to embodiment 17 or 18.

[0130] 20. The method according to embodiment 17, wherein one or more hydrophilic polymers (2) are present in the hydrophilic layer and the hydrophilic polymer comprises a repeating unit containing a carboxylic acid, phosphonic acid, or phosphate group and optionally a repeating unit containing an amide group.

[0131] 21. The method according to embodiment 17, wherein one or more hydrophilic polymers (2) are present in the hydrophilic layer and the ratio of the C1 dry coating amount to the C2 dry coating amount is at least 11:9 to 30:1 or less.

[0132] The following examples are provided to illustrate the implementation of the present invention and are not intended to be limiting in any way.

[0133] Examples 1-16 and Comparative Examples 1-8 of the present invention: Type A and Type B aluminum-containing substrates used in the production of the negative-type infrared-sensitive lithographic printing plate precursors of the examples and comparative examples of the present invention were produced according to the above general process.

[0134] Type A support: This aluminum-containing support produced as the aluminum-containing substrate of Example 1 of the present invention is described in U.S. Patent No. 10,363,734 (above). Therefore, the Type A support had an inner aluminum oxide layer and an outer aluminum oxide layer.

[0135] Type B support: This aluminum-containing support was manufactured as a Type 3 substrate (or "support") containing aluminum, which is described in U.S. Patent Application No. 17 / 189,497, filed on March 2, 2021, and currently published as U.S. Patent Application Publication No. 2022 / 0194112A1 (above). Thus, the Type B support had an inner aluminum oxide layer, an intermediate aluminum oxide layer, and an outer aluminum oxide layer.

[0136] Synthesis of Copolymer for Hydrophilic Layer: Polymer 1, a copolymer derived from vinylphosphonic acid and acrylamide (molar ratio 1:9), was prepared as follows. 3500 g of ethanol was placed in a 10-liter reaction vessel equipped with a cooler and heated to 70°C. 231.1 g of vinylphosphonic acid monomer and 1368.9 g of acrylamide monomer were mixed in 1000 g of ethanol, and 52 g of a commercially available azobisisobutyronitrile (AIBN) polymerization initiator was dissolved in the monomer mixture. Then, this monomer mixture containing AIBN was added dropwise to the 10-liter reaction vessel at 70°C over 4 hours. After this addition, the resulting reaction mixture was held at 70°C for 2 hours and then cooled to room temperature. The resulting copolymer of Polymer 1 was precipitated as a white powder, isolated by filtration, and washed with 1 liter of ethanol. The polymer yield was measured to be 1550 g.

[0137] Preparation of Hydrophilic Layer Formulation: Hydrophilic layer formulations for use in various examples were prepared using the components listed in Table I below.

[0138]

Table 1A

[0139]

Table 1B

[0140]

Table 1C

[0141] ACUMER (trademark) 1000 Polymer is an aqueous solution (50% by weight) of poly(acrylic acid) obtained from The Dow Chemical Company.

[0142] Takesurf (trademark) D-410-GL is a leveling agent obtained from TAKEMOTO OIL & FAT CO., LTD.

[0143] Each hydrophilic layer formulation shown in Table I was coated onto samples of Type A or B supports using a wire wound coating bar at a wet coating weight of 20 g / m 2 and dried at 80 °C for 2 minutes. The dry coating weights of each dried hydrophilic layer are shown in Table I above.

[0144] Production of an on-machine developable negative-type infrared-sensitive original plate: Coating formulations MC-1, MC-2, and MC-3 for an on-machine developable negative-type infrared-sensitive image-forming layer were prepared by dissolving or dispersing the components and amounts shown in Table II below at a total solids content of 5% by weight in a coating solvent mixture of 35% by weight n-propanol, 20% by weight 2-methoxypropanol, 35% by weight 2-butanone, and 10% by weight water.

[0145] The raw materials specified in Table II below can be obtained from one or more commercial sources of chemicals or prepared using known synthetic methods and starting materials. Other materials are described in Table III below.

[0146]

Table 2

[0147]

Table 3

[0148] The coatings of these formulations were applied onto an aluminum-containing substrate including a hydrophilic layer using a wire-wound coating bar, and dried at 80 °C for 2 minutes to obtain an on-press developable negative-type infrared-sensitive image recording layer each having a dry coating amount of 1 g / m 2 . The obtained original lithographic printing plates are shown in Table IV below.

[0149]

Table 4A

[0150]

Table 4B

[0151] Each of the original lithographic printing plates specified above was imaged at an exposure energy of 150 mJ / cm in the solid area using a Kodak Magnus 800 imagesetter. 2

[0152] The following evaluations were performed on each of the imaged originals or the corresponding non-imaged originals.

[0153] On-press developability (DOP): Each of the original lithographic printing plates was imaged as described above and then mounted on a Roland R-201 printing press for on-press development. The printing press was supplied with dampening water [Presarto WS 100, sold by DIC Graphics / isopropyl alcohol / water 1 / 1 / 98 (volume ratio)], a S-7400 blanket (Kin-yo-sha), OK Top Coat Paper Matt N grade paper (Oji paper) as printing paper, and lithographic printing ink (Fusion G Magenta N, sold by DIC Graphics), and printing was performed at a printing speed of 9,000 sheets / hour. The on-press developability was evaluated by the number of printed sheets (or impressions) at the point when no further ink transfer was observed in the non-image area.

[0154] The DOP of the following two types of lithographic printing plates was evaluated. Each sample of the original lithographic printing plate was packaged with light-shielding paper immediately after production and stored at 25°C for 7 days (when specified as "NK7"). Also, each sample of the original lithographic printing plate was stored in a commercially available humidity chamber ETAC FX-430 at 40°C and 80% RH for 7 days (when specified as "HT7").

[0155] In the evaluation, a DOP of less than 50 prints is preferable, and a DOP exceeding 100 prints is unacceptable under these printing conditions. The smaller the number of gaps between the DOP when specified as NK7 and the DOP when specified as HT7, the better the stability of the original plate over time after production.

[0156] Printing life without ozone exposure: Each of the original lithographic printing plates was imaged as described above, and the resulting image original plate was mounted on a Komori S-26 printing press at 8,000 rpm. An aqueous solution mixture of 1% K701 (DIC Graphics) and 10% isopropanol was used as dampening water, a S-7400 blanket (Kin-yo-sha), OK Top Coat Paper Matt N grade paper (Oji paper) was used as printing paper, and K Magenta N grade lithographic printing ink (DIC Graphics) was used to evaluate the printing life.

[0157] As the number of sheets (number of copies or prints) of printed paper was continuously increased, the negative-type infrared-sensitive image-forming layer that could be developed on the lithographic printing plate gradually wore out, and the ink receptivity of this layer decreased. As a result, the ink density of the printed paper decreased. The printing life was determined as the number of copies (or prints) when the reflection density of the solid area of the obtained printed paper decreased to 90% of that at the start of printing. The greater the number of copies (or prints) at which this deterioration occurred, the better the printing life.

[0158] Printing life with ozone exposure: Before image formation, each of the lithographic printing plate precursors was exposed to a controlled amount of ozone inside a commercially available humidity chamber ETAC FX-430 in which the ozone concentration was controlled to 1 ppm and the chamber temperature was controlled to 25°C. The following apparatus was used to control the ozone concentration: Kotohira portable ozone generator KPO-T01 as an ozone source, Kanomax Gasmaster model number 2750 as an ozone monitor.

[0159] The ozone exposure time for each precursor was 6 hours, corresponding to an ozone exposure amount of 21,600 ppm·s (where "ppm" is the unit of ozone concentration in parts per million by volume and "s" is the abbreviation for seconds, the unit of time). After this exposure to ozone, each precursor was imagewise exposed and evaluated for printing life as described above for the precursors not exposed to ozone.

[0160] The results of all these evaluations are shown in Table V below.

[0161]

Table 5A

[0162]

Table 5B

[0163] From the results shown in Table V, it can be seen that the precursors of Examples 1 to 16 of the present invention containing an anionic IR dye and the aluminum-containing substrate of the present invention showed the desired rapid on-press development and a small DOP gap for the imagewise exposed precursors labeled as NK7 and for the imagewise exposed precursors labeled as HT7. These precursors of the present invention showed a long printing life for image formation regardless of whether the unexposed precursors were exposed to ozone or not.

[0164] The precursors of Comparative Examples 1, 4, and 7 contained an anionic IR dye, but the dry coating amount of phosphoric acid in the hydrophilic layer was 300 mg / m 2Since it exceeded [the specified value], it included an aluminum-containing substrate outside the scope of the present invention. These original plates showed the formed original plates from when they were labeled as NK7, the desired rapid in-flight development of the formed original plates when labeled as HT7, and a small DOP gap. The original plates of these comparative examples showed insufficient printing life regardless of whether the unformed original plates were exposed to ozone.

[0165] The original plates of Comparative Examples 2, 3, 5, and 8 contained an anionic IR dye, but since the dry coating amount of phosphoric acid in the hydrophilic layer was less than 50 mg / m 2 it included an aluminum-containing substrate outside the scope of the present invention. These showed a long printing life regardless of whether the unformed original plates were exposed to ozone, but showed extremely slow in-flight development after HT7 and a large DOP gap. Such extremely slow in-flight development after HT7 is thought to be caused by a salt formed between the anionic chromophore of the infrared absorber in the in-flight-developable negative-type infrared image-forming layer and the aluminum ions Al 3+ of aluminum sulfate released from the anode layer of the substrate of the present invention during storage of the original plate under HT7 conditions.

[0166] The original plate of Comparative Example 6 contained a cationic dye and an aluminum-containing substrate according to the present invention. However, this original plate showed the desired rapid in-flight development when specified as NK7, showed in-flight development when specified as HT7, had a small DOP gap, and the unformed original plate showed a long printing life when not exposed to ozone. However, these original plates showed insufficient printing life when exposed to ozone before image formation.

Claims

1. An original lithographic printing plate comprising: an aluminum-containing substrate having a hydrophilic surface; and a on-press-developable negative-type infrared-sensitive image-forming layer disposed on the hydrophilic surface of the aluminum-containing substrate, wherein the aluminum-containing substrate is an aluminum-containing plate having a granulated and etched surface, An inner aluminum oxide layer disposed on the granulated and etched surface, having an average dry thickness (T i ) of at least 300 nm to 3000 nm or less, and containing a plurality of inner pores with an average inner pore diameter (D i ) of 11 nm or less, and containing aluminum sulfate, the inner aluminum oxide layer, An outer aluminum oxide layer disposed on the inner aluminum oxide layer, the outer aluminum oxide layer including a large number of outer pores having an average outer pore diameter (D o ), which is at least 12 nm to 50 nm or less, and having an average dry thickness (T o ), which is at least 20 nm to 650 nm or less, and the outer aluminum oxide layer, and including a hydrophilic layer disposed on the outer aluminum oxide layer, wherein the hydrophilic layer (1) has a C1 dry coating amount and the following formula (I): 【Chemical 1】 (wherein n is 0 or an integer of 1 to 10, and -OM is -OH or -O － M ＋ represents M ＋ is a monovalent cation), and optionally one or more phosphorus-containing compounds represented by and (2) when present, contains one or more hydrophilic polymers having a C2 dry coating amount, The dry coating amount of C1 of the above-mentioned one or more phosphorus-containing compounds (1) is at least 50 mg / m 2 to 300 mg / m 2 or less, and when the above-mentioned one or more hydrophilic polymers (2) are present, the ratio of the dry coating amount of C1 to the dry coating amount of C2 is at least 11:9, wherein the on-press-developable negative-type infrared-sensitive image-forming layer contains the following components (a) to (c), and optionally component (d): (a) one or more free-radically polymerizable components, (b) an initiator composition that gives free radicals when the on-press-developable negative-type infrared-sensitive image-forming layer is exposed to image-forming infrared rays, (c) one or more infrared absorbers containing an anionic chromophore having a net negative charge or an acidic group, and optionally (d) one or more polymer binders, all of which are different from all of components (a), (b), and (c) An original lithographic printing plate comprising the above components.

2. The C1 dry coating amount is at least 75 mg / m 2 to 200 mg / m 2 or less. The original lithographic printing plate according to claim 1.

3. The original lithographic printing plate according to claim 1 or 2, wherein the ratio of the C1 dry coating amount to the C2 dry coating amount is at least 11:9 to 30:1 or less.

4. The above-mentioned one or more infrared absorbers (c) are present in the developable-on-machine negative infrared-sensitive image-forming layer at a dry coating amount of at least 10 mg / m 2 to 200 mg / m 2 The lithographic printing plate precursor according to any one of claims 1 to 3.

5. The original lithographic printing plate according to any one of claims 1 to 4, wherein the one or more hydrophilic polymers (2) are present in the hydrophilic layer, and the one or more hydrophilic polymers (2) include a hydrophilic polymer containing a repeating unit containing a carboxylic acid, phosphonic acid, phosphate group, or a salt or ester of any of these acids, and optionally a repeating unit containing an amide group.

6. M ＋ is independently selected from the group consisting of a proton, a sodium cation, a potassium cation, an ammonium cation, an alkylammonium cation, a dialkylammonium cation, a trialkylammonium cation, and a tetraalkylammonium cation, each alkyl group being optionally substituted, the lithographic printing plate original according to any one of claims 1 to 5.

7. The original lithographic printing plate according to any one of claims 1 to 6, wherein the -OM group is selected such that when the one or more phosphorus-containing compounds (1) represented by formula (I) are dissolved in an aqueous solution containing 5% by weight of the one or more phosphorus-containing compounds (1) represented by formula (I), the one or more phosphorus-containing compounds (1) represented by formula (I) exhibit a pH of at least 1 to 10 or less.

8. The anionic chromophore having a net negative charge or an acidic group is represented by the following formula (II) 【Chemical 2】 (wherein, Each X independently represents >S, >O, >NR, or >C(R) 2 and represents Each R 1 is, independently, an optionally substituted alkyl group, R 2 represents hydrogen, halogen, -SR, -SO 2 R, -OR, or -NR 2 group, and Each R 3 independently represents a hydrogen atom, an optionally substituted alkyl group, -COO － , -COOR, -OR, -SR, -NR 2 , a halogen atom, a sulfonate group, or an optionally substituted benzo-fused ring, --- represents an optionally present carbocyclic 5-membered or 6-membered ring, Each R independently represents hydrogen, an optionally substituted alkyl group, or an optionally substituted aryl group, each n independently is 0, 1, 2, or 3, R 1 、R 2 、and R 3 at least one of which is a sulfonate group, a carboxylate group, or both a sulfonate group and a carboxylate group in order to impart a net negative charge or an acidic group to formula (II)) The original lithographic printing plate according to any one of claims 1 to 7, represented by

9. R 1 、 R 2 、 and R 3 wherein at least one of 1 , 2 , and 3 contains a carboxylate group to provide a net negative charge or an acidic group with respect to formula (II), the original lithographic printing plate precursor according to claim 8.

10. The outer aluminum oxide layer has an average dry thickness (T o ) of at least 50 nm, the outer aluminum oxide layer is disposed directly on the inner aluminum oxide layer, the average dry thickness (T i ) of the inner aluminum oxide layer is at least 500 nm, the average inner pore diameter (D i ) is 11 nm or less, and is smaller than the average outer pore diameter (D o ), the lithographic printing plate precursor according to any one of claims 1 to 9.

11. The aluminum-containing substrate further includes an intermediate aluminum oxide layer disposed between the inner aluminum oxide layer and the outer aluminum oxide layer, and the intermediate aluminum oxide layer has an average dry thickness (T m ), which is at least 60 nm to 300 nm or less, and includes a plurality of intermediate pores having an average intermediate pore diameter (D m ) of at least 20 nm to 60 nm or less, D m is larger than D o , D o is larger than D i , and the average dry thickness (T o ) of the outer aluminum oxide layer is less than 150 nm. The original lithographic printing plate according to any one of claims 1 to 10.

12. The original lithographic printing plate according to any one of claims 1 to 11, wherein the on-machine developable negative infrared-sensitive layer further contains the one or more polymer binders (d), and at least one of them is in particulate form.

13. The original lithographic printing plate according to any one of claims 1 to 12, wherein the on-machine developable negative infrared-sensitive image-forming layer is the outermost layer.

14. The original lithographic printing plate according to any one of claims 1 to 13, wherein the one or more hydrophilic polymers (2) are present, and the hydrophilic polymer contains a repeating unit containing one or more of a carboxylic acid group, a carboxylate, or a carboxylate group, and contains at least 50 mol% of all repeating units.

15. The original lithographic printing plate according to any one of claims 1 to 14, wherein the one or more hydrophilic polymers (2) are present, and the hydrophilic polymer contains a repeating unit containing a carboxylic acid, a phosphonic acid, or a phosphate group and a repeating unit containing an amide group.

16. A method for providing a lithographic printing plate, comprising: imagewise exposing the original lithographic printing plate according to any one of claims 1 to 15 to image-forming infrared rays to form an imagewise infrared-exposed image-forming layer having exposed areas and unexposed areas, and using lithographic printing ink, dampening water, or both lithographic printing ink and dampening water to remove the unexposed areas from the imagewise infrared-exposed image-forming layer on the machine to form a lithographic printing plate The method comprising.

17. A method for manufacturing the original lithographic printing plate according to any one of claims 1 to 15, comprising: A) providing an aluminum-containing plate having an electrochemically or mechanically granulated and etched surface, B) A step of subjecting the aluminum-containing plate to a first anodization process to form an outer aluminum oxide layer on the electrochemically or mechanically granulated and etched surface, wherein the outer aluminum oxide layer contains a large number of outer pores with an average outer pore diameter (D o ), which is at least 12 nm to 50 nm or less, and has an average dry thickness (T o ) of at least 20 nm to 650 nm or less, and subjecting it to a first anodization process. C) rinsing the outer aluminum oxide layer, D) A step of subjecting the aluminum-containing plate to an additional anodization process using sulfuric acid to form an inner aluminum oxide layer under the outer aluminum oxide layer, wherein the inner aluminum oxide layer has an average dry thickness (T i ) of at least 300 nm to 3000 nm or less and contains a number of inner pores with an average inner pore diameter (D i ) of 11 nm or less, and the inner aluminum oxide layer contains aluminum sulfate, the step of subjecting to an additional anodization process E) rinsing the outer aluminum oxide layer and the inner aluminum oxide layer, F) providing a hydrophilic layer on the outer aluminum oxide layer, wherein the hydrophilic layer (1) has a C1 dry coating amount and the following formula (I): 【Chemical Formula 3】 (wherein n is an integer of 0 or 1 to 10, and -OM represents -OH or -O － M ＋ represents, and M ＋ is a monovalent cation), one or more phosphorus-containing compounds represented by the formula, and optionally (2) contains one or more hydrophilic polymers having a C2 dry coating amount when present, The dry coating amount of the above-mentioned one or more phosphorus-containing compounds (1) is at least 50 mg / m 2 to 300 mg / m 2 or less, and the ratio of the dry coating amount of C1 to the dry coating amount of C2 when the above-mentioned one or more hydrophilic polymers (2) are present is at least 11:9, a step of providing a hydrophilic layer, and G) A step of forming an in-air-developable negative-type infrared-sensitive image-forming layer on the outer aluminum oxide layer, wherein the in-air-developable negative-type infrared-sensitive image-forming layer contains the following components (a) to (c), and optionally component (d): (a) One or more free-radical polymerizable components, (b) An initiator composition that gives free radicals when the in-air-developable negative-type infrared-sensitive image-forming layer is exposed to image-forming infrared rays, (c) One or more infrared absorbers containing an anionic chromophore having a net negative charge or an acidic group, and optionally (d) One or more polymer binders, all of which are different from all of components (a), (b), and (c) A step of forming an in-air-developable negative-type infrared-sensitive image-forming layer containing them A method including these steps in this order.

18. The method according to claim 17, wherein the first anodization process is carried out using phosphoric acid.

19. Between step C) and step D), C') subjecting the aluminum-containing plate to a second anodization process to form an intermediate aluminum oxide layer under the outer aluminum oxide layer, the intermediate aluminum oxide layer having an average dry thickness (T m ) of at least 60 nm to 300 nm or less, and including a plurality of intermediate pores having an average intermediate pore diameter (D m ) of at least 20 nm to 60 nm or less, D m being larger than D o , D o being larger than D i , and further including the step of subjecting to a second anodization process in which the average dry thickness (T o ) of the outer aluminum oxide layer is less than 150 nm The additional anodization process of step D) is a third anodization process for forming the inner aluminum oxide layer under the intermediate aluminum oxide layer. The method according to claim 17 or 18.

20. The method according to any one of claims 17 to 19, wherein the one or more hydrophilic polymers (2) are present in the hydrophilic layer and contain a hydrophilic polymer containing a repeating unit containing a carboxylic acid, phosphonic acid, or phosphate group and optionally a repeating unit containing an amide group.

21. The method according to any one of claims 17 to 20, wherein the one or more hydrophilic polymers (2) are present in the hydrophilic layer and the ratio of the C1 dry coating amount to the C2 dry coating amount is at least 11:9 to 30:1 or less.

Images