Laminate for negative type lithographic printing plate original and method for producing negative type lithographic printing plate

Abstract

The present application provides a kind of layer stack and the manufacturing method of negative type lithographic printing plate, the layer stack is the layer stack of negative type lithographic printing plate original version with at least 1 layer comprising infrared absorber with HOMO being-5.43eV or less on hydrophilic support body, in the negative type lithographic printing plate original version, the arithmetic mean height Sa of the outermost layer surface of at least one side comprising the infrared absorber of at least 1 layer with the support body as reference and the opposite side thereof is 0.3 μm or more and 20 μm or less.

Description

TECHNICAL FIELD

[0001] The present application relates to a layered body of a negative type lithographic printing plate precursor and a method for producing a negative type lithographic printing plate. BACKGROUND

[0002] Generally, a lithographic printing plate is composed of an oleophilic image portion that accepts ink in a printing process and a hydrophilic non-image portion that accepts dampening water. Lithographic printing is a method in which, by utilizing the property that water and oily ink repel each other, the oleophilic image portion of a lithographic printing plate is made as an ink-receptive portion, the hydrophilic non-image portion is made as a dampening water-receptive portion (non-ink-receptive portion), an adhesion difference of ink is generated on the surface of the lithographic printing plate, and then the ink is transferred to a printing material such as paper after the ink is applied only to the image portion, and printing is performed.

[0003] At present, in a plate-making process of producing a lithographic printing plate from a lithographic printing plate precursor, image exposure using CTP (Computer-to-Plate) technology is performed. That is, image exposure is performed directly on a lithographic printing plate precursor by scanning exposure or the like using a laser or a laser diode without passing through a high-contrast film.

[0004] Furthermore, due to the increasing concern for the global environment, in plate-making of a lithographic printing plate precursor, environmental problems related to waste liquid accompanying wet processing such as development processing have become apparent, and in response to this, simplification or non-processing of development processing is being directed. As one of the simple development processing, a method called "on-press development" has been proposed. On-press development is a method in which, after image exposure of a lithographic printing plate precursor, instead of the conventional wet development processing, the lithographic printing plate precursor is directly mounted on a printing machine, and removal of the non-image portion of the image recording layer is performed at the initial stage of the usual printing process.

[0005] A lithographic printing plate precursor in which an image recording layer containing a polymerization initiator, an infrared absorber, a polymerizable compound, and an acid color developer, the infrared absorber containing a specific compound, is provided on a hydrophilic support is disclosed in Patent Literature 1.

[0006] PRIOR ART DOCUMENTS

[0007] PATENT LITERATURE

[0008] Patent Literature 1: International Publication No. 2019 / 013268 SUMMARY

[0009] PROBLEMS TO BE SOLVED BY THE INVENTION

[0010] In recent years, there has been a demand for further improvement in the print durability of a printing plate obtained from a lithographic printing plate precursor (in this specification, also referred to as "print durability of a lithographic printing plate precursor over time") by long-term storage of the lithographic printing plate precursor.

[0011] Also, the lithographic printing plate precursors are generally stored and transported as a stack of a plurality of the precursors. Also, in a case where the stack is accommodated in a chiller tray of a chiller and one lithographic printing plate precursor is taken out from the stack at the time of exposure or the like to perform plate feeding, it is required to take out the lithographic printing plate precursor from the stack more smoothly.

[0012] The present application was accomplished in view of the foregoing circumstances, and an object thereof is to provide a stack of negative-type lithographic printing plate precursors, which is excellent in print durability over time and excellent in chiller plate feeding property, and a method for producing a negative-type lithographic printing plate.

[0013] Means for solving the technical problem

[0014] The following describes a manner for solving the above problem. [1]

[0016] A stack of negative-type lithographic printing plate precursors having at least one layer containing an infrared absorber having a HOMO of -5.43 eV or less on a hydrophilic support,

[0017] In the above negative-type lithographic printing plate precursor, an arithmetic mean height Sa of an outermost surface of at least one of the side of the at least one layer containing the above infrared absorber on the above support and the side opposite thereto is 0.3 μm or more and 20 μm or less. [2]

[0019] The stack according to [1], wherein

[0020] The HOMO of the above infrared absorber is -5.45 eV or less. [3]

[0022] The stack according to [1] or [2], wherein

[0023] The above infrared absorber is a compound represented by the following formula (1).

[0024] [Chemical Formula 1]

[0025]

[0026] R1and R2each independently represent a hydrogen atom or an alkyl group, R1and R2may be linked to each other to form a ring, R3to R6each independently represent a hydrogen atom or an alkyl group, R7and R8each independently represent an alkyl group or an aryl group, Y1and Y2each independently represent an oxygen atom, a sulfur atom, -NR0-, or a dialkyl methylene group, R0represents a hydrogen atom, an alkyl group, or an aryl group, Ar1and Ar2each independently represent a group forming a benzene ring or a naphthalene ring which can have a group represented by the following formula 2, A1represents -NR9R 10 , -X1-X 11 -L1or a group represented by the following formula 2,

[0027] R9and R 10 each independently represent an alkyl group, an aryl group, an alkoxycarbonyl group, an arylsulfonyl group, or a trihaloalkylsulfonyl group, X1represents an oxygen atom or a sulfur atom, X 11 represents a single bond or an alkylene group, L1represents a hydrocarbon group, a heteroaryl group, or a group which is cleaved from X1by heat or infrared exposure, and Za represents a counter ion for neutralizing a charge.

[0028] -X formula 2

[0029] X represents a halogen atom, -C(=O)-X2-R 11 R 12 R 13 , -O-C(=O)-R 14 , -CN, -SO2NR 15 R 16 or a perfluoroalkyl group, X2represents a single bond or an oxygen atom, R 11 represents a hydrogen atom, an alkyl group, or an aryl group, R 14 represents an alkyl group or an aryl group, R 12 , R 13 , R 15 and R 16 each independently represent a hydrogen atom, an alkyl group, or an aryl group. [4]

[0031] A laminate according to [3] wherein A1in the above formula (1) is -NR 17 R 18 or -S-X 12 -R 19 .

[0032] R 17 and R 18 each independently represent an aryl group, R 19 represents a hydrocarbon group or a heteroaryl group, and X 12 represents a single bond or an alkylene group. [5]

[0034] A laminate of [3] or [4] of the above formula 2, wherein X is a fluorine atom, a chlorine atom, a bromine atom, or -C(=O)OR 20

[0035] R 20 represents a hydrogen atom, an alkyl group, or an aryl group. [6]

[0037] The laminate according to any one of [1] to [5], wherein

[0038] The above lithographic printing plate precursor has an image recording layer. [7]

[0040] The laminate according to [6], wherein

[0041] The at least one layer containing the above infrared absorber is the above image recording layer. [8]

[0043] The laminate according to [6] or [7], wherein

[0044] The above image recording layer contains a polymerization initiator, a polymerizable compound, and a high molecular compound. [9]

[0046] The laminate according to [8], wherein

[0047] The above high molecular compound is a high molecular compound containing at least one of a structural unit derived from a styrene compound and a structural unit derived from an acrylonitrile compound.

[10]

[0049] The laminate according to [9], wherein

[0050] In the high molecular compound containing the structural unit derived from the styrene compound and the structural unit derived from the acrylonitrile compound, the composition ratio of the structural unit derived from the styrene compound to the structural unit derived from the acrylonitrile compound is 4:1 to 1:4.

[11]

[0052] The laminate according to any one of [8] to

[10] , wherein

[0053] The above high molecular compound is a polymer particle.

[12]

[0055] The laminate according to [8], wherein

[0056] The above high molecular compound contains at least a polyvinyl butyl resin.

[13] ​

[0058] The laminate according to any one of [6] to

[12] , wherein

[0059] The image recording layer contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

[14]

[0061] The laminate according to any one of [6] to

[13] , wherein

[0062] The image recording layer contains at least two kinds of particles having an average particle diameter of 0.5 μm or more and 20 μm or less and different average particle diameters.

[15]

[0064] The laminate according to any one of [6] to

[14] , wherein

[0065] The lithographic printing plate precursor according to any one of [6] to

[14] , wherein

[16]

[0067] The laminate according to

[15] , wherein

[0068] The at least one layer containing the infrared absorber is the protective layer.

[17]

[0070] The laminate according to

[15] or

[16] , wherein

[0071] The protective layer contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

[18]

[0073] The laminate according to any one of [6] to

[17] , wherein

[0074] The outermost layer on the side opposite to the side of the at least one layer containing the infrared absorber with respect to the support contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

[19]

[0076] The laminate according to any one of [6] to

[18] , wherein

[0077] The support is an aluminum support having an anodized film,

[0078] The average diameter of the micropores at the surface of the anodized film of the support is 10 to 100 nm, and the value of the lightness L* in the L*a*b* color system of the surface of the at least one layer containing the infrared absorber on the side of the anodized film is 70 to 100.

[20]

[0080] The laminate according to any one of [6] to

[19] , wherein

[0081] The support is an aluminum support having an anodized film,

[0082] The micropores in the anodized film of the support are composed of large-diameter pore portions extending from the surface of the anodized film to a depth of 10 nm to 1,000 nm and small-diameter pore portions communicating with the bottoms of the large-diameter pore portions and extending from the communicating positions to a depth of 20 nm to 2,000 nm, the average diameter of the large-diameter pore portions at the surface of the anodized film is 15 nm to 100 nm, and the average diameter of the small-diameter pore portions at the communicating positions is 13 nm or less.

[21]

[0084] The laminate according to any one of [6] to

[19] , wherein

[0085] The support is an aluminum support having an anodized film,

[0086] The micropores in the anodized film of the support are composed of small-diameter pore portions extending from the surface of the anodized film to a depth of 10 nm to 1,000 nm and large-diameter pore portions communicating with the bottoms of the small-diameter pore portions and extending from the communicating positions to a depth of 20 nm to 2,000 nm, the average diameter of the small-diameter pore portions at the surface of the anodized film is 35 nm or less, and the average diameter of the large-diameter pore portions is 40 to 300 nm.

[22]

[0088] The laminate according to any one of [6] to

[21] , wherein

[0089] The laminate is one in which a plurality of the lithographic printing plate precursors are directly overlaid without interposition of a backing paper.

[23]

[0091] The laminate according to any one of [6] to

[22] , wherein

[0092] The end portion of the lithographic printing plate precursor has a shape of a bevel having a bevel amount X of 25 to 150 μm and a bevel width Y of 70 to 300 μm.

[24]

[0094] The laminate according to

[23] , wherein

[0095] A portion or all of the side surfaces of the opposite two edges of the lithographic printing plate precursor have a repelling agent.

[25]

[0097] A method for producing a negative type lithographic printing plate, including the steps of: taking out the above-mentioned lithographic printing plate precursor from the laminate described in any one of [6] to

[24] ; image-exposing the above-mentioned lithographic printing plate precursor; and supplying at least one of a printing ink and a dampening solution and removing an unexposed portion of the image-recording layer in the above-mentioned lithographic printing plate precursor.

[0098] Effects of Invention

[0099] According to the present application, it is possible to provide a laminate of a negative type lithographic printing plate precursor, which is excellent in print durability over time and excellent in plate setting performance, and a method for producing a negative type lithographic printing plate. BRIEF DESCRIPTION OF DRAWINGS

[0100] Figure 1 is a chart showing an example of a waveform of an alternating waveform current used in an electrochemical roughening treatment.

[0101] Figure 2 is a side view showing an example of a radial type cell in an electrochemical roughening treatment using alternating current.

[0102] Figure 3 is a schematic view showing a cross-sectional shape of an end portion of a lithographic printing plate precursor.

[0103] Figure 4 is a conceptual view showing an example of a cutting portion of a slitting device.

[0104] Figure 5 is a side view showing a concept of a brush polishing step used in a mechanical roughening treatment at the time of producing an aluminum support.

[0105] Figure 6 is a schematic view of an anodizing treatment device used in an anodizing treatment.

[0106] Figure 7 is a view explaining a method of applying an ink repellent. DETAILED DESCRIPTION

[0107] The following description of the components is made according to a representative embodiment of the present application, but the present application is not limited to this embodiment.

[0108] In the notation of groups (radicals) in this specification, the notation of substituted and unsubstituted includes not only groups having no substituent (unsubstituted groups), but also groups having a substituent (substituted groups). For example, "alkyl groups" include not only alkyl groups having no substituent (unsubstituted alkyl groups), but also alkyl groups having a substituent (substituted alkyl groups).

[0109] In the present specification, "(meth)acrylic acid" is a term used as a meaning including both of acrylic acid and methacrylic acid, and "(meth)acryloyl group" is a term used as a meaning including both of acryloyl group and methacryloyl group.

[0110] The term "step" in the present specification includes not only a single step, but also a step which cannot be distinguished from other steps, as long as the intended purpose of the step can be achieved.

[0111] In the present application, a combination of two or more of the preferable modes is a more preferable mode.

[0112] In the present specification, the mass average molecular weight (Mw) and the number average molecular weight (Mn) are molecular weights calculated as polystyrene by using a gel permeation chromatography (GPC) analysis device using a column of TSKgel GMHxL, TSKgel G4000HxL, TSKgel G2000HxL (all are trade names manufactured by TOSOH CORPORATION), and by solvent THF (tetrahydrofuran), differential refractometer detection, and using polystyrene as a standard material, unless otherwise specified.

[0113] Hereinafter, the present application will be described in detail.

[0114] [Layered body of negative type lithographic printing plate precursor]

[0115] The layered body according to the present application is a layered body of a negative type lithographic printing plate precursor (hereinafter, sometimes referred to as "lithographic printing plate precursor") having at least one layer containing an infrared absorber having a HOMO of -5.43 eV or less on a hydrophilic support, wherein the arithmetic average height Sa of the outermost surface of at least one of the side of the at least one layer containing the infrared absorber described above on the support described above and the side opposite thereto is 0.3 μm or more and 20 μm or less.

[0116] As a result of intensive studies by the present inventors, it has been found that by adopting the above structure, a layered body of a lithographic printing plate precursor which is excellent in print durability over time and excellent in plate setting performance by a plate setter can be provided.

[0117] The detailed mechanism by which the above effects can be obtained is not clear, but is presumed as follows.

[0118] With regard to the print durability over time of the lithographic printing plate precursor, the present inventors focused on the infrared absorber contained in the layer on the support in the lithographic printing plate precursor. As a result of further studies, it has been found that the infrared absorber described above is decomposed due to long-term storage (storage over time) in air, and the print durability over time of the lithographic printing plate precursor is deteriorated.

[0119] Accordingly, the present inventors focused on the HOMO (highest occupied molecular orbital) of the infrared absorber and selected an infrared absorber having a HOMO energy level of -5.43 eV or less, and unexpectedly obtained the insight that the print durability of the lithographic printing plate precursor over time was improved. It is presumed that this is because the decomposition of the infrared absorber contained in the layer on the support over time is suppressed, and the image portion of the printing plate obtained via the exposure process and the development process is formed in a state close to that before the passage of time.

[0120] Also, in the case where the stack of the lithographic printing plate precursors is set to the plate cylinder of the processing machine, and the lithographic printing plate precursor is taken out, it is required to peel off the lithographic printing plate precursors adjacent to the lithographic printing plate precursor smoothly. As a result of the present inventors' intensive studies on the shape of the outermost surface of each lithographic printing plate precursor constituting the stack, the present inventors focused on the shape of the outermost surface of at least one of the side of at least one layer having the above-described infrared absorber in the lithographic printing plate precursor with reference to the support and the side opposite thereto. It was found that by setting the arithmetic mean height Sa of the above-described outermost surface to 0.3 μm or more, one lithographic printing plate precursor can be taken out from the stack very smoothly. It is presumed that this is because by providing an appropriate gap between the lithographic printing plate precursors, vacuum adhesion is suppressed.

[0121] Also, typically, the stack is formed by overlapping a plurality of (usually 100 or more) lithographic printing plate precursors, and therefore if the arithmetic mean height Sa of the above-described outermost surface exceeds 20 μm, the plurality of lithographic printing plate precursors constituting the stack tend to be difficult to fix when the stack is made. Also, in the exposure process, the development process, and the printing process, there is a concern that the member in contact with the outermost surface is subjected to damage such as scratching. Therefore, in the present specification, the upper limit of the arithmetic mean height Sa of the above-described outermost surface is set to 20 μm.

[0122] It is presumed from the above that the plate setting property in the case where the lithographic printing plate precursor is taken out from the stack is improved.

[0123] The stack of the lithographic printing plate precursors according to the present application is preferably a stack formed by directly overlapping a plurality of (usually 2 to 500) lithographic printing plate precursors without a backing paper.

[0124] [Lithographic printing plate precursor]

[0125] The lithographic printing plate precursor of the present application is a lithographic printing plate precursor having at least one layer containing an infrared absorber having a HOMO of -5.43 eV or less on a hydrophilic support, and an arithmetic mean height Sa of the outermost surface of at least one of the layer containing the infrared absorber on the side of the above-mentioned support and the side opposite thereto is 0.3 μm or more and 20 μm or less.

[0126] Hereinafter, the lithographic printing plate precursor will be described in detail.

[0127] The hydrophilic support (hereinafter, also referred to simply as "support") of the lithographic printing plate precursor of the present application can be appropriately selected from publicly known hydrophilic supports for lithographic printing plate precursors and used. As the hydrophilic support, an aluminum support subjected to roughening by a publicly known method and anodization treatment (specifically, an aluminum support having an anodized film) is preferred.

[0128] [Aluminum support having an anodized film]

[0129] An aluminum support having an anodized film, which is a preferred mode of the support constituting the lithographic printing plate precursor, will be described.

[0130] The aluminum plate used in the aluminum support contains a metal having aluminum as a main component, i.e., aluminum or aluminum alloy, which is dimensionally stable. It is preferred to select from a pure aluminum plate and an alloy plate having aluminum as a main component and containing a trace amount of foreign elements.

[0131] The foreign elements contained in the aluminum alloy include silicon, iron, manganese, copper, magnesium, chromium, zinc, bismuth, nickel, titanium, and the like. The content of the foreign elements in the alloy is 10 mass% or less. A pure aluminum plate is preferred, but from the viewpoint of smelting technology, completely pure aluminum is difficult to produce, and thus an alloy plate containing a small amount of foreign elements can be used. The composition of the aluminum plate used in the aluminum support is not particularly limited, and a publicly known aluminum plate, such as JIS A 1050, JIS A 1100, JIS A 3103, JIS A 3005, and the like, can be appropriately used.

[0132] The thickness of the aluminum plate is preferably about 0.1 to 0.6 mm.

[0133] (anodized film)

[0134] The anodized film refers to an anodized aluminum film having ultrafine pores (also referred to as micropores) formed on the surface of the aluminum plate by anodization treatment. The micropores extend from the surface of the anodized film on the side opposite to the aluminum plate in the thickness direction (aluminum plate side, depth direction).

[0135] From the viewpoint of tone reproducibility, print durability, and brush contamination, the average diameter (average opening diameter) of the micro-holes at the surface of the anodized film is preferably 7 nm to 150 nm, more preferably 10 nm to 100 nm, further preferably 10 nm to 60 nm, particularly preferably 15 nm to 60 nm, and most preferably 18 nm to 40 nm.

[0136] The depth of the micro-holes is preferably 10 nm to 3,000 nm, more preferably 10 nm to 2,000 nm, and further preferably 10 nm to 1,000 nm.

[0137] The shape of the micro-holes is generally a substantially straight pipe shape (substantially cylindrical shape) in which the diameter of the micro-holes hardly changes with the depth direction (thickness direction), but can be a conical shape in which the diameter continuously decreases with the depth direction (thickness direction). Also, it can be a shape in which the diameter discontinuously and decreases with the depth direction (thickness direction).

[0138] As the shape in which the diameter discontinuously and decreases with the depth direction (thickness direction), there can be mentioned a micro-hole composed of a large-diameter hole portion extending from the surface of the anodized film in the depth direction and a small-diameter hole portion communicating with the bottom of the large-diameter hole portion and extending from the communicating position in the depth direction.

[0139] Specifically, a micro-hole composed of a large-diameter hole portion extending from the surface of the anodized film in the depth direction by 10 nm to 1,000 nm and a small-diameter hole portion communicating with the bottom of the large-diameter hole portion and extending from the communicating position further in the depth direction by 20 to 2,000 nm is preferred.

[0140] Hereinafter, the large-diameter hole portion and the small-diameter hole portion will be described in detail.

[0141] - Large-diameter hole portion -

[0142] From the viewpoint of tone reproducibility, print durability, and brush contamination, the average diameter (average opening diameter) of the large-diameter hole portion at the surface of the anodized film is preferably 7 nm to 150 nm, more preferably 10 nm to 100 nm, further preferably 15 nm to 100 nm, particularly preferably 15 nm to 60 nm, and most preferably 18 nm to 40 nm.

[0143] The average diameter of the large-diameter hole portion is obtained by observing the surface of the anodized film using a field emission type scanning electron microscope (FE-SEM) at a magnification of 150,000 times (N = 4), measuring the diameter of the micro-holes (large-diameter hole portions) present in a range of 400 nm x 600 nm in the obtained four images, and calculating the arithmetic mean of the diameters.

[0144] In addition, in the case where the shape of the large-diameter hole portion is not circular, the circular equivalent diameter is used. The "circular equivalent diameter" refers to the diameter of a circle having the same projected area as the opening portion when the shape of the opening portion is assumed to be a circle.

[0145] The bottom of the large-diameter hole portion is preferably located at a depth of 70 nm to 1,000 nm (hereinafter, also referred to as depth A) from the surface of the anodized film. That is, the large-diameter hole portion is preferably a hole portion extending 70 nm to 1,000 nm in the depth direction (thickness direction) from the surface of the anodized film. Of these, from the viewpoint of more excellent effects in the method of manufacturing the lithographic printing plate precursor, the depth A is more preferably 90 nm to 850 nm, further preferably 90 nm to 800 nm, and particularly preferably 90 nm to 600 nm.

[0146] In addition, regarding the above depth, a photograph (15 million times) of the cross section of the anodized film is taken, the depths of 25 or more large-diameter hole portions are measured, and the average value thereof is calculated.

[0147] The shape of the large-diameter hole portion is not particularly limited, and for example, a substantially straight pipe shape (substantially cylindrical shape) and a conical shape in which the diameter decreases toward the depth direction (thickness direction) can be given, and a substantially straight pipe shape is preferred. Furthermore, the shape of the bottom of the large-diameter hole portion is not particularly limited, and can be a curved surface shape (convex shape) or a flat surface shape.

[0148] The inner diameter of the large-diameter hole portion is not particularly limited, but is preferably the same order of magnitude as the diameter of the opening portion or smaller than the diameter of the opening portion. In addition, the inner diameter of the large-diameter hole portion can differ from the diameter of the opening portion by about 1 nm to 10 nm.

[0149] - Small-diameter hole portion -

[0150] The small-diameter hole portion is a hole portion that communicates with the bottom of the large-diameter hole portion and extends further in the depth direction (thickness direction) from the communication position. One small-diameter hole generally communicates with one large-diameter hole portion, but two or more small-diameter hole portions can communicate with the bottom of one large-diameter hole portion.

[0151] The average diameter of the small-diameter hole portion at the communication position is preferably 13 nm or less, more preferably 11 nm or less, and particularly preferably 10 nm or less. The lower limit is not particularly limited, but is preferably 5 nm.

[0152] The average diameter of the small-diameter hole portion is calculated by observing the anodized film surface with FE-SEM at a magnification of 150,000 times, N = 4, measuring the diameter of the micropores (small-diameter hole portions) present in a range of 400 nm x 600 nm in the four obtained images, and calculating the arithmetic mean of the diameters. In addition, in the case where the depth of the large-diameter hole portion is deep, the upper portion of the anodized film (the region having the large-diameter hole portion) can be cut (for example, by argon gas) as necessary, and then the anodized film surface is observed with the above FE-SEM, and the average diameter of the small-diameter hole portion is calculated.

[0153] In addition, in the case where the shape of the small-diameter hole portion is not circular, the circular equivalent diameter is used. The "circular equivalent diameter" refers to the diameter of a circle when the shape of the opening portion is assumed to be a circle having the same projected area as the projected area of the opening portion.

[0154] The bottom of the small-diameter hole portion is preferably located at a position extending further along the depth direction from the communication position with the above large-diameter hole portion (corresponding to the above depth A) by 20 nm to 2,000 nm. In other words, the small-diameter hole portion is a hole portion extending further along the depth direction (thickness direction) from the communication position with the above large-diameter hole portion, and the depth of the small-diameter hole portion is preferably 20 nm to 2,000 nm, more preferably 100 nm to 1,500 nm, and particularly preferably 200 nm to 1,000 nm.

[0155] In addition, with respect to the above depth, a photograph (150,000 times) of the cross section of the anodized film is taken, the depth of 25 or more small-diameter hole portions is measured, and the arithmetic mean is calculated.

[0156] The shape of the small-diameter hole portion is not particularly limited, and for example, a substantially straight pipe shape (substantially cylindrical shape) and a conical shape in which the diameter decreases toward the depth direction can be given, and a substantially straight pipe shape is preferred. Furthermore, the shape of the bottom of the small-diameter hole portion is not particularly limited, and can be curved (convex) or planar.

[0157] The inner diameter of the small-diameter hole portion is not particularly limited, but can be the same size as the diameter at the communication position, or can be smaller or larger than the above diameter. In addition, the inner diameter of the small-diameter hole portion can generally differ from the diameter of the opening portion by about 1 nm to 10 nm.

[0158] The ratio of the average diameter of the large-diameter hole portion at the anodized film surface to the average diameter of the small-diameter hole portion at the communication position, (average diameter of the large-diameter hole portion at the anodized film surface) / (average diameter of the small-diameter hole portion at the communication position), is preferably 1.1 to 13, and more preferably 2.5 to 6.5.

[0159] Further, the ratio of the depth of the large-diameter hole portion to the depth of the small-diameter hole portion, (depth of large-diameter hole portion) / (depth of small-diameter hole portion), is preferably 0.005 to 50, more preferably 0.025 to 40.

[0160] Further, the shape of the micropore is substantially straight pipe shape (substantially cylindrical shape) in which the diameter of the micropore hardly changes with the depth direction (thickness direction), but can be conical shape in which the diameter continuously increases with the depth direction (thickness direction). Further, it can be a shape in which the diameter discontinuously and increases with the depth direction (thickness direction).

[0161] As the shape in which the diameter discontinuously and increases with the depth direction (thickness direction), there can be mentioned a micropore composed of a small-diameter hole portion extending from the surface of the anodized film along the depth direction and a large-diameter hole portion communicating with the bottom of the small-diameter hole portion and extending from the communicating position along the depth direction.

[0162] Specifically, it is preferable that the micropore be composed of a small-diameter hole portion extending from the surface of the anodized film along the depth direction by 10 nm to 1,000 nm and a large-diameter hole portion communicating with the bottom of the small-diameter hole portion and extending from the communicating position further along the depth direction by 20 to 2,000 nm.

[0163] Small-diameter hole portion

[0164] The average diameter (average opening diameter) of the small-diameter hole portion at the surface of the anodized film is not particularly limited, but is preferably 35 nm or less, more preferably 25 nm or less, and particularly preferably 20 nm or less. The lower limit is not particularly limited, but is preferably 15 nm.

[0165] The average diameter of the small-diameter hole portion is obtained by observing the surface of the anodized film using a field emission type scanning electron microscope (FE-SEM) at a magnification of 150,000 times (N = 4), measuring the diameter of the micropore (large-diameter hole portion) present in a range of 400 nm x 600 nm in the obtained four images, and calculating the arithmetic mean of the diameters.

[0166] In addition, in the case where the shape of the small-diameter hole portion is not circular, the circular equivalent diameter is used. The "circular equivalent diameter" means the diameter of a circle when the shape of the opening portion is assumed to be a circle having the same projected area as the projected area of the opening portion.

[0167] The bottom of the small-diameter hole portion is preferably located at a depth of 70 nm to 1,000 nm from the surface of the anodized film (hereinafter, also referred to as depth A). That is, the small-diameter hole portion is preferably a hole portion extending from the surface of the anodized film along the depth direction (thickness direction) by 70 nm to 1,000 nm.

[0168] Further, regarding the above-mentioned depth, a photograph (150,000 times) of a cross section of the anodic oxide film was taken, the depths of 25 or more large-diameter hole portions were measured, and the arithmetic mean value thereof was calculated.

[0169] The shape of the small-diameter hole portion is not particularly limited, and for example, a substantially straight pipe shape (substantially cylindrical shape) and a conical shape in which the diameter increases toward the depth direction (thickness direction) can be given, and a substantially straight pipe shape is preferred. Further, the shape of the bottom of the small-diameter hole portion is not particularly limited, and can be a curved surface (convex) or a flat surface.

[0170] The inner diameter of the small-diameter hole portion is not particularly limited, but is preferably the same order of magnitude as the diameter of the opening portion or smaller than the diameter of the opening portion. Further, the inner diameter of the small-diameter hole portion can differ from the diameter of the opening portion by about 1 nm to 10 nm.

[0171] - Large-diameter hole portion -

[0172] The large-diameter hole portion is a hole portion that communicates with the bottom of the small-diameter hole portion and further extends in the depth direction (thickness direction) from the communication position. One large-diameter hole portion can generally be a communication position of two or more small-diameter hole portions and the bottom of one large-diameter hole portion.

[0173] The average diameter of the large-diameter hole portion at the communication position is preferably 20 nm to 400 nm, more preferably 40 nm to 300 nm, further preferably 50 nm to 200 nm, and particularly preferably 50 nm to 100 nm.

[0174] The average diameter of the large-diameter hole portion is calculated by observing the surface of the anodic oxide film with an FE-SEM at a magnification of 150,000 times, N = 4, and in the four obtained images, the diameter of the micropore (large-diameter hole portion) present in a range of 400 nm x 600 nm is measured, and the arithmetic mean value of the diameters is calculated. Further, in the case where the depth of the small-diameter hole portion is deep, the upper portion of the anodic oxide film (a region having a small-diameter hole portion) can be cut (for example, by argon gas), and then the surface of the anodic oxide film is observed with the above-mentioned FE-SEM, and the average diameter of the large-diameter hole portion is calculated.

[0175] Further, in the case where the shape of the large-diameter hole portion is not circular, the circular equivalent diameter is used. The "circular equivalent diameter" refers to the diameter of a circle when the shape of the opening portion is assumed to be a circle having the same projected area as the projected area of the opening portion.

[0176] The bottom of the large-diameter hole portion is preferably located at a position extending 20 nm to 2,000 nm further along the depth direction from the communication position with the small-diameter hole portion (corresponding to the depth A' described above). In other words, the large-diameter hole portion is a hole portion extending further along the depth direction (thickness direction) from the communication position with the small-diameter hole portion, and the depth of the large-diameter hole portion is preferably 20 nm to 2,000 nm, more preferably 100 nm to 1,500 nm, and particularly preferably 200 nm to 1,000 nm.

[0177] In addition, regarding the depth, a photograph (15 million times) of a cross section of the anodic oxide film was taken, the depths of 25 or more large-diameter hole portions were measured, and the average was calculated as an arithmetic average.

[0178] The shape of the large-diameter hole portion is not particularly limited, and for example, a substantially straight pipe shape (substantially cylindrical shape) and a conical shape in which the diameter decreases toward the depth direction can be given, and a substantially straight pipe shape is preferred. Also, the shape of the bottom of the large-diameter hole portion is not particularly limited, and can be curved (convex) or flat.

[0179] The inner diameter of the large-diameter hole portion is not particularly limited, but can be the same size as the diameter at the communication position, or can be smaller or larger than the diameter described above. In addition, the inner diameter of the large-diameter hole portion can generally differ from the diameter of the opening portion by about 1 nm to 10 nm.

[0180] In the on-press development type lithographic printing plate precursor, it is useful for the brightness of the anodic oxide film surface of the aluminum support (the surface of the side on which at least one layer containing the infrared absorber described above is formed) to be high from the viewpoint of improving the visual recognition of the image.

[0181] In the printing process of a lithographic printing plate, a plate inspection operation is generally performed in order to confirm whether or not the image recording formed as intended has been performed before the printing plate is mounted on a printing machine. In the on-press development type lithographic printing plate precursor, it is required to confirm the image at the stage after image exposure, and therefore a mechanism that produces a so-called print-out image is applied to the image exposure portion.

[0182] As a method for quantitatively evaluating the ease of viewing (image visual recognition) of the image portion of the on-press development type lithographic printing plate precursor after image exposure, a method in which the brightness of the image exposure portion and the brightness of the unexposed portion are measured, and the difference between the two is calculated can be given. Here, as the brightness, the value of the brightness L* in the CIE L*a*b* color system can be used, and regarding the measurement, a color difference meter (SpectroEye, manufactured by X-Rite Inc.) can be used. The greater the difference between the brightness of the image exposure portion and the brightness of the unexposed portion obtained by the measurement, the easier it is to see the image portion.

[0183] It was ascertained that, in order to increase the difference between the brightness of the exposed part and the brightness of the unexposed part of the image, it is effective for the value of the brightness L* in the CIE L*a*b* color system of the surface of the anodized film to be large. That is, the value of the brightness L* is preferably 60 to 100, and preferably 70 to 100.

[0184] The aluminum support body having the anodized film can have a back coating layer containing an organic high molecular compound described in Japanese Patent Application Publication No. 5-45885 or a siloxane compound containing silicon described in Japanese Patent Application Publication No. 6-35174 on the side opposite to the side on which at least one layer containing the above-described infrared absorber is formed, as needed.

[0185] (Method for manufacturing aluminum support body having anodized film)

[0186] The aluminum support body having the anodized film can be manufactured using a publicly known method. The method for manufacturing the aluminum support body having the anodized film is not particularly limited. As a preferable method for manufacturing the aluminum support body having the anodized film, a method including the following steps can be given: a step of subjecting an aluminum plate to roughening treatment (roughening treatment step); a step of anodizing the aluminum plate subjected to the roughening treatment (anodizing treatment step); and a step of bringing the aluminum plate having the anodized film obtained in the anodizing treatment step into contact with an aqueous acid solution or an aqueous alkali solution to enlarge the diameter of the micropores in the anodized film (enlargement treatment step)

[0187] Hereinafter, each step will be described in detail.

[0188] <roughening treatment step>

[0189] The roughening treatment step is a step of subjecting the surface of the aluminum plate to roughening treatment including electrochemical roughening treatment. The roughening treatment step is preferably performed before the anodizing treatment step described later, but if the surface of the aluminum plate already has a preferable surface shape, the step need not be performed.

[0190] As for the roughening treatment, electrochemical roughening treatment can be performed alone, but can also be performed in combination with at least one of mechanical roughening treatment and chemical roughening treatment.

[0191] In the case of combining mechanical roughening treatment and electrochemical roughening treatment, the electrochemical roughening treatment is preferably performed after the mechanical roughening treatment.

[0192] The electrochemical roughening treatment is preferably performed in an aqueous solution of nitric acid, hydrochloric acid.

[0193] As for the mechanical roughening treatment, it is generally performed in order to set the surface of the aluminum plate to a surface roughness Ra: 0.35 to 1.0 μm.

[0194] The various conditions of the mechanical roughening treatment are not particularly limited, but for example, it can be performed according to the method described in Japanese Patent No. 50-40047. The mechanical roughening treatment can be performed by brush texturing using a pumice suspension, or by a transfer method.

[0195] Also, the chemical roughening treatment is not particularly limited, and can be performed according to a known method.

[0196] It is preferable to perform the following chemical etching treatment after the mechanical roughening treatment.

[0197] The chemical etching treatment performed after the mechanical roughening treatment is performed for the purpose of smoothing the edge portions of the concave-convex shape of the surface of the aluminum plate, preventing catching on of ink at the time of printing, thereby improving the contamination resistance of the lithographic printing plate, and removing unnecessary substances such as abrasive particles remaining on the surface.

[0198] As the chemical etching treatment, etching using an acid, etching using a base are known, but as a method that is particularly excellent in etching efficiency, a chemical etching treatment using a base solution (hereinafter, also referred to as "base etching treatment") can be cited.

[0199] The base agent used in the base solution is not particularly limited, but for example, caustic soda, caustic potash, sodium metasilicate, sodium carbonate, sodium aluminate, sodium gluconate, and the like are preferably selected.

[0200] The base solution can contain aluminum ions. The concentration of the base agent of the base solution is preferably 0.01% by mass or more, more preferably 3% by mass or more, and is preferably 30% by mass or less, more preferably 25% by mass or less.

[0201] Also, the temperature of the base solution is preferably room temperature or higher, more preferably 30°C or higher, and is preferably 80°C or lower, more preferably 75°C or lower.

[0202] The etching amount is preferably 0.01 g / m 2 or more, more preferably 0.05 g / m 2 or more, and is preferably 30 g / m 2 or more, more preferably 20 g / m 2 or more.

[0203] The processing time corresponding to the etching amount is preferably 2 seconds to 5 minutes, and more preferably 2 to 10 seconds from the viewpoint of improving productivity.

[0204] In the case where the base etching treatment is performed after the mechanical roughening treatment, in order to remove the products generated by the base etching treatment, it is preferable to perform a chemical etching treatment using an acidic solution at low temperature (hereinafter, also referred to as "stain removal treatment").

[0205] The acid used in the acidic solution is not particularly limited, but for example, sulfuric acid, nitric acid, and hydrochloric acid can be given. The concentration of the acidic solution is preferably 1 to 50% by mass. The temperature of the acidic solution is preferably 20 to 80°C. If the concentration and the temperature of the acidic solution are within the range, the spot-like stain resistance in the lithographic printing plate using the aluminum support is further improved.

[0206] The following illustrates a preferable mode of the roughening treatment step.

[0207] -Mode SA-

[0208] A mode in which the treatments shown in (1) to (8) are sequentially performed.

[0209] (1) Chemical etching treatment using an aqueous alkali solution (1st alkali etching treatment)

[0210] (2) Chemical etching treatment using an aqueous acidic solution (1st stain removal treatment)

[0211] (3) Electrochemical roughening treatment using an aqueous solution mainly containing nitric acid (1st electrochemical roughening treatment)

[0212] (4) Chemical etching treatment using an aqueous alkali solution (2nd alkali etching treatment)

[0213] (5) Chemical etching treatment using an aqueous acidic solution (2nd stain removal treatment)

[0214] (6) Electrochemical roughening treatment using an aqueous solution mainly containing hydrochloric acid (2nd electrochemical roughening treatment)

[0215] (7) Chemical etching treatment using an aqueous alkali solution (3rd alkali etching treatment)

[0216] (8) Chemical etching treatment using an aqueous acidic solution (3rd stain removal treatment)

[0217] -Mode SB-

[0218] A mode in which the treatments shown in (11) to (15) are sequentially performed.

[0219] (11) Chemical etching treatment using an aqueous alkali solution (4th alkali etching treatment)

[0220] (12) Chemical etching treatment using an aqueous acidic solution (4th stain removal treatment)

[0221] (13) Electrochemical roughening treatment using an aqueous solution mainly containing hydrochloric acid (3rd electrochemical roughening treatment)

[0222] (14) Chemical etching treatment using an aqueous alkali solution (5th alkali etching treatment)

[0223] (15) Chemical etching treatment using an acidic aqueous solution (5th dirt removing treatment)

[0224] If necessary, a mechanical roughening treatment can be performed before the (1) treatment of the above-described mode SA or before the (11) treatment of the mode SB.

[0225] The dissolution amount of the aluminum plate in the 1st alkaline etching treatment and the 4th alkaline etching treatment is preferably 0.5 g / m 2 ~ 30 g / m 2 , more preferably 1.0 g / m 2 ~ 20 g / m 2 .

[0226] As the nitric acid-based aqueous solution used in the 1st electrochemical roughening treatment in the mode SA, an aqueous solution used in an electrochemical roughening treatment using direct current or alternating current can be given. For example, an aqueous solution obtained by adding aluminum nitrate, sodium nitrate or ammonium nitrate or the like to a 1 g / L to 100 g / L nitric acid aqueous solution can be given.

[0227] As the hydrochloric acid-based aqueous solution used in the 2nd electrochemical roughening treatment in the mode SA and the 3rd electrochemical roughening treatment in the mode SB, an aqueous solution used in an electrochemical roughening treatment using direct current or alternating current can be given. For example, an aqueous solution obtained by adding 0 g / L to 30 g / L of sulfuric acid to a 1 g / L to 100 g / L hydrochloric acid aqueous solution can be given. In addition, nitric acid ions such as aluminum nitrate, sodium nitrate or ammonium nitrate; chloride ions such as aluminum chloride, sodium chloride or ammonium chloride can be further added to the aqueous solution.

[0228] The alternating current power source waveform of the electrochemical roughening treatment can use a sine wave, a rectangular wave, a trapezoidal wave or a triangular wave or the like. The frequency is preferably 0.1 Hz to 250 Hz.

[0229] Figure 1 is a chart showing an example of the alternating waveform current waveform chart used in the electrochemical roughening treatment.

[0230] Figure 1In this context, ta represents the anode reaction time, tc represents the cathode reaction time, tp represents the time it takes for the current to reach its peak value from 0, Ia represents the peak current on the anode circulation side, and Ic represents the peak current on the cathode circulation side. In the trapezoidal wave, the time tp for the current to reach its peak value from 0 is preferably 1 msec to 10 msec. The preferred conditions for one cycle of AC current used for electrochemical roughening treatment are: the ratio of the anode reaction time ta to the cathode reaction time tc (tc / ta) of the aluminum plate is 1 to 20; the ratio of the charge Qc when the aluminum plate is the anode to the charge Qa when the aluminum plate is the anode (Qc / Qa) is 0.3 to 20; and the anode reaction time ta is in the range of 5 msec to 1,000 msec. Regarding current density, the peak current on both the anode circulation side (Ia) and the cathode circulation side (Ic) of the trapezoidal wave are preferably 10 to 200 A / dm². 2 The Ic / Ia ratio is preferably 0.3 to 20. The total charge participating in the anodic reaction of the aluminum plate at the end of the electrochemical roughening treatment is preferably 25 C / dm². 2 ~1,000C / dm 2 .

[0231] In electrochemical roughening treatment using alternating current, it is possible to use Figure 2 The apparatus shown.

[0232] Figure 2 This is a side view showing an example of a radial unit in an electrochemical roughening process using alternating current.

[0233] exist Figure 2 In the diagram, 50 is the main electrolytic cell, powered by AC; 52 is the radial drum roller; 53a and 53b are the main electrodes; 54 is the electrolyte supply port; 55 is the electrolyte; 56 is the slit; 57 is the electrolyte channel; 58 is the auxiliary anode; 60 is the auxiliary anode tank; and W is the aluminum plate. When using two or more electrolytic cells, the electrolysis conditions can be the same or different.

[0234] An aluminum plate W is rolled onto a radial drum roller 52, which is immersed in the main electrolytic cell 50, and electrolyzed during transport via main electrodes 53a and 53b connected to an AC power supply 51. Electrolyte 55 is supplied from the electrolyte supply port 54 through a slit 56 to the electrolyte channel 57 between the radial drum roller 52 and the main electrodes 53a and 53b. The aluminum plate W, after being treated in the main electrolytic cell 50, is then electrolyzed in an auxiliary anode tank 60. In this auxiliary anode tank 60, an auxiliary anode 58 is positioned opposite the aluminum plate W, and electrolyte 55 is supplied in a manner that flows through the space between the auxiliary anode 58 and the aluminum plate W.

[0235] From the viewpoint of facilitating the manufacture of the original lithographic printing plate, the amount of aluminum plate dissolved in the second alkaline etching process is preferably 1.0 g / m². 2 ~20g / m2 More preferably, 2.0 g / m 2 ~ 10 g / m 2 .

[0236] From the viewpoint of easy manufacturing of a prescribed lithographic printing plate precursor, the amount of dissolution of the aluminum plate in the third alkali etching treatment and the fifth alkali etching treatment is preferably 0.01 g / m 2 ~ 0.8 g / m 2 , more preferably 0.05 g / m 2 ~ 0.3 g / m 2 .

[0237] In the chemical etching treatment using an acidic aqueous solution (the first to fifth cleaning treatments), an acidic aqueous solution containing phosphoric acid, nitric acid, sulfuric acid, chromic acid, hydrochloric acid, or a mixed acid containing two or more of these acids can be preferably used.

[0238] The concentration of the acid in the acidic aqueous solution is preferably 0.5 mass% to 60 mass%.

[0239] <Anodizing Treatment Step>

[0240] The anodizing treatment step is a step of forming an oxide film of aluminum on the surface of the aluminum plate by subjecting the aluminum plate on which the above-described roughening treatment has been performed to an anodizing treatment. By the anodizing treatment, an anodized oxide film of aluminum having micropores is formed on the surface of the aluminum plate.

[0241] The anodizing treatment can be performed by appropriately setting the manufacturing conditions in consideration of the shape of the micropores and the like, according to a method known in the field hitherto.

[0242] In the anodizing treatment step, an aqueous solution of sulfuric acid, phosphoric acid, oxalic acid, or the like can be mainly used as an electrolyte. Depending on the case, an aqueous solution or a non-aqueous solution of chromic acid, sulfamic acid, benzenesulfonic acid, or the like, or a combination of two or more of these can also be used. If direct current or alternating current is passed through the aluminum plate in the electrolyte, an anodized oxide film can be formed on the surface of the aluminum plate. Aluminum ions can be contained in the electrolyte. The content of the aluminum ions is not particularly limited, but is preferably 1 to 10 g / L.

[0243] The conditions of the anodizing treatment can be appropriately set depending on the electrolyte used, but generally, it is appropriate that the concentration of the electrolyte is in the range of 1 to 80 mass% (preferably 5 to 20 mass%), the liquid temperature is in the range of 5 to 70°C (preferably 10 to 60°C), the current density is in the range of 0.5 to 60 A / dm 2 (preferably 5 to 50 A / dm 2 ), the voltage is in the range of 1 to 100 V (preferably 5 to 50 V), and the electrolysis time is in the range of 1 to 100 seconds (preferably 5 to 60 seconds).

[0244] The method of anodizing in sulfuric acid at a high current density described in the specification of British Patent No. 1,412,768 is a preferred example of an anodizing treatment.

[0245] The anodizing treatment can also be performed multiple times. One or more of the conditions used in each anodizing treatment, such as the type, concentration, temperature, current density, voltage, and electrolysis time of the electrolyte, can be changed. In the case where the number of anodizing treatments is two, the first anodizing treatment is sometimes referred to as the first anodizing treatment, and the second anodizing treatment is sometimes referred to as the second anodizing treatment. By performing the first anodizing treatment and the second anodizing treatment, an anodized film having a different shape can be formed, and thus a lithographic printing plate precursor having excellent printing performance can be provided.

[0246] Furthermore, the following pore expanding treatment can be performed after the anodizing treatment, and then the anodizing treatment can be performed again. In this case, the first anodizing treatment, the pore expanding treatment, and the second anodizing treatment are performed.

[0247] By using the method of performing the first anodizing treatment, the pore expanding treatment, and the second anodizing treatment, a micropore composed of a large-diameter pore portion extending in the depth direction from the surface of the aforementioned anodized film and a small-diameter pore portion communicating with the bottom of the large-diameter pore portion and extending in the depth direction from the communication position can be formed.

[0248] <the pore expanding treatment step>

[0249] The pore expanding treatment step is a treatment for expanding the diameter (pore diameter) of the micropore present in the anodized film formed by the aforementioned anodizing treatment step (pore diameter expanding treatment). By this pore expanding treatment, the diameter of the micropore is expanded, and an anodized film having a micropore with a larger average diameter is formed.

[0250] The pore expanding treatment can be performed by bringing the aluminum plate obtained by the aforementioned anodizing treatment step into contact with an aqueous acid solution or an aqueous alkali solution. The method of contact is not particularly limited, and for example, immersion, and spraying can be given. Among these, immersion is preferred.

[0251] In the case where an aqueous alkali solution is used in the pore expanding treatment step, it is preferred to use an aqueous alkali solution selected from at least one of sodium hydroxide, potassium hydroxide, and lithium hydroxide. The concentration of the aqueous alkali solution is preferably 0.1 to 5% by mass. It is appropriate to adjust the pH of the aqueous alkali solution to 11 to 13, and to bring the aluminum plate into contact with the aqueous alkali solution at a temperature of 10 to 70°C (preferably 20 to 50°C) for 1 to 300 seconds (preferably 1 to 50 seconds). At this time, a metal salt of a polyvalent weak acid such as a carbonate, a borate, or a phosphate can be contained in the alkali treatment solution.

[0252] In the case where an aqueous acid solution is used in the hole expansion treatment step, an aqueous solution of an inorganic acid such as sulfuric acid, phosphoric acid, nitric acid, hydrochloric acid, or a mixture thereof is preferably used. The concentration of the aqueous acid solution is preferably 1 to 80 mass%, more preferably 5 to 50 mass%. It is appropriate that the aluminum plate is contacted with the aqueous acid solution at a liquid temperature of 5 to 70°C (preferably 10 to 60°C) for 1 to 300 seconds (preferably 1 to 150 seconds).

[0253] Aluminum ions can be contained in the aqueous alkali solution or the aqueous acid solution. The content of the aluminum ions is not particularly limited, but is preferably 1 to 10 g / L.

[0254] The method for producing the aluminum support body having the anodic oxide film can include a hydrophilic treatment step of performing a hydrophilic treatment after the above hole expansion treatment step. In the hydrophilic treatment, the publicly known method described in paragraphs 0109 to 0114 of Japanese Patent Application Publication No. 2005-254638 can be used.

[0255] The hydrophilic treatment is preferably performed by a method of dipping in an aqueous solution of an alkali metal silicate such as sodium silicate or potassium silicate, a method of forming a hydrophilic primer layer by applying a hydrophilic vinyl polymer or a hydrophilic compound, or the like.

[0256] The hydrophilic treatment using an aqueous solution of an alkali metal silicate such as sodium silicate or potassium silicate can be performed according to the method and the procedure described in U.S. Patent No. 2,714,066 and U.S. Patent No. 3,181,461.

[0257] [At least one layer containing an infrared absorber having a HOMO of -5.43 eV or less]

[0258] Described is at least one layer (hereinafter, also referred to as "specific structure layer") constituting a lithographic printing plate precursor, which contains an infrared absorber having a HOMO of -5.43 eV or less.

[0259] The specific structure layer contains an infrared absorber having a HOMO of -5.43 eV or less.

[0260] (Infrared absorber having a HOMO of -5.43 eV or less)

[0261] The specific structure layer contains an infrared absorber having a HOMO of -5.43 eV or less (hereinafter, also referred to as "specific infrared absorber").

[0262] The infrared absorber has a function of moving electrons and / or energy to a polymerization initiator or the like upon excitation by infrared rays. Also, it has a function of converting the absorbed infrared rays into heat. The infrared absorber preferably has a large absorption in the wavelength region of 750 to 1,400 nm. As the specific infrared absorber, a dye or pigment having a HOMO of -5.43 eV or less can be cited, and a dye is preferably cited.

[0263] As the dye, a commercially available dye and a well-known dye described in documents such as "Dye Handbook" (The Society of Synthetic Organic Chemistry, Japan. Edited, published in 45 years of Showa) can be used. Specifically, azo dyes, metal complex salt azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinonimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, metal thiol complexes, and the like can be cited.

[0264] Among the dyes, cyanine pigments, squarylium pigments, pyrylium salts are preferred, and cyanine pigments are more preferred, and indocyanine pigments are particularly preferred.

[0265] The calculation method of the HOMO of the compound in the present application is performed by the following method. First, the counter anion in the compound to be calculated is ignored. Using quantum chemistry calculation software Gaussian 16, structure optimization is performed under DFT (B3LYP / 6-31G(d)).

[0266] MO (molecular orbital) energy calculation is performed on the structure obtained by the above structure optimization under DFT (B3LYP / 6-31+G(d, p) / CPCM (solvent = methanol)). The MO energy Epre (unit: Hartree) obtained by the above MO energy calculation is converted to Eaft (unit: eV) which is the value used as the HOMO in the present application according to the following formula.

[0267] Eaft = 0.823161 x 27.2114 x Epre - 1.07634

[0268] In addition, 27.2114 is a coefficient for converting Hartree to eV only, and 0.823161 and -1.07634 are adjustment coefficients, and the HOMO of the compound to be calculated is determined so as to match the calculation with the measured value.

[0269] The above specific infrared absorber is preferably a compound represented by the following formula (1).

[0270] [Chemical Formula 2]

[0271]

[0272] R1and R2each independently represent a hydrogen atom or an alkyl group, R1and R2may be linked to each other to form a ring, R3to R6each independently represent a hydrogen atom or an alkyl group, R7and R8each independently represent an alkyl group or an aryl group, Y1and Y2each independently represent an oxygen atom, a sulfur atom, -NR0-, or a dialkyl methylene group, R0represents a hydrogen atom, an alkyl group, or an aryl group, Ar1and Ar2each independently represent a group forming a benzene ring or a naphthalene ring which can have a group represented by the following formula 2, A1represents -NR9R 10 11 -L1or a group represented by the following formula 2,

[0273] R9and R 10 each independently represent an alkyl group, an aryl group, an alkoxycarbonyl group, an arylsulfonyl group, or a trihaloalkylsulfonyl group, X1represents an oxygen atom or a sulfur atom, X 11 represents a single bond or an alkylene group, L1represents a hydrocarbon group, a heteroaryl group, or a group which is cleaved from X1by heat or infrared exposure, and Za represents a counter ion for neutralizing a charge.

[0274] -X formula 2

[0275] X represents a halogen atom, -C(=O)-X2-R 11 12 R 13 , -O-C(=O)-R 14 , -CN, -SO2NR 15 R 16 or a perfluoroalkyl group, X2represents a single bond or an oxygen atom, R 11 represents a hydrogen atom, an alkyl group, or an aryl group, R 14 represents an alkyl group or an aryl group, R 12 , R 13 , R 15 and R 16 each independently represent a hydrogen atom, an alkyl group, or an aryl group.

[0276] Ar1and Ar2each independently represent a group forming a benzene ring or a naphthalene ring. On the above benzene ring and naphthalene ring, a substituent other than -X can be present. As the substituent, an alkyl group, an alkoxy group, an aryloxy group, an amino group, an alkylthio group, an arylthio group, a carboxylate group, a sulfo group, a sulfonate group, and a group formed by combining them, and the like can be mentioned, but an alkyl group is preferred.

[0277] Ar1and Ar2may each independently have a group represented by the above formula 2.

[0278] ​​Furthermore, in formula (1), as a preferred embodiment, at least one of Ar1 and Ar2 has the group represented by formula 2 above. As a preferred embodiment, from the viewpoint of printability and reducing HOMO value, it is preferable that both Ar1 and Ar2 have the group represented by formula 2 above.

[0279] At least one of Ar1 and Ar2 may have a plurality of groups represented by the above formula 2.

[0280] In Equation 2, X represents a halogen atom, -C(=O)-X2-R 11 -C(=0)-NR 12 R 13 -OC(=O)-R 14 -CN, -SO2NR 15 R 16 Alternatively, perfluoroalkyl groups, from the viewpoint of reducing the HOMO of a specific infrared absorber and suppressing the decomposition of the specific infrared absorber over time, are preferred, preferably halogen atoms, -C(=O)-X2-R 11 -C(=O)-NR 12 R 13 -OC(=O)-R 14 CN or -SO2NR 15 R 16 Preferably, halogen atoms, -C(=O)-OR 11 -C(=O)-NR 12 R 13 or -OC(=O)-R 14 Further preferred are halogen atoms, -C(=O)-OR 11 or -OC(=O)-R 14 Especially preferred are fluorine atoms, chlorine atoms, bromine atoms, or -C(=O)OR 20 .

[0281] Examples of halogen atoms include fluorine, chlorine, or bromine atoms, but chlorine atoms are preferred.

[0282] X2 represents a single bond or an oxygen atom, preferably an oxygen atom.

[0283] R 11 The term represents a hydrogen atom, an alkyl group, or an aryl group, preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and more preferably an alkyl group having 1 to 12 carbon atoms.

[0284] R 14 The term represents alkyl or aryl, preferably alkyl with 1 to 12 carbon atoms or aryl with 6 to 12 carbon atoms, and more preferably alkyl with 1 to 12 carbon atoms.

[0285] R12 , R 13 , R 15 , and R 16 each independently represent a hydrogen atom, an alkyl group, or an aryl group, preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, further preferably an alkyl group having 1 to 12 carbon atoms.

[0286] R 20 represents a hydrogen atom, an alkyl group, or an aryl group, preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aryl group having 6 to 12 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms.

[0287] Further, the above alkyl group or aryl group can have a substituent. As examples of the substituent, there can be mentioned an alkoxy group, an aryloxy group, an amino group, an alkylthio group, an arylthio group, a halogen atom, a carboxyl group, a carboxylate group, a sulfo group, a sulfonate group, an alkoxycarbonyl group, an aryloxycarbonyl group, and a group formed by combining them, etc.

[0288] A1represents -NR9R 10 , -X1-X 11 -L1or -X, preferably -NR9R 10 or -X1-X 11 -L1, more preferably -NR 17 R 18 or -S-X 12 -R 19 .

[0289] R1and R 10 each independently represent an alkyl group, an aryl group, an alkoxycarbonyl group, an arylsulfonyl group, or a trihaloalkylsulfonyl group.

[0290] As the alkyl group in the alkoxycarbonyl group, the same groups as the alkyl group of R9and R 10 can be mentioned.

[0291] As the aryl group in the arylsulfonyl group, the same groups as the aryl group of R9and R 10 can be mentioned.

[0292] As the alkyl group in the trihaloalkylsulfonyl group, the same groups as the alkyl group of R9and R 10 can be mentioned.

[0293] As the trihaloalkylsulfonyl group, for example, a trifluoromethylsulfonyl group can be mentioned.

[0294] R9and R 10Each of R1and R2independently represents a hydrogen atom, an alkyl group, an aryl group or an alkenyl group. Each of R1and R2is preferably an alkyl group or an aryl group, more preferably an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and still more preferably an alkyl group having 1 to 12 carbon atoms.

[0295] X1represents an oxygen atom or a sulfur atom, and in the case where L1is a hydrocarbon group or a heteroaryl group, it is preferably a sulfur atom. L1is preferably a group which is cleaved from X1by heat or infrared exposure. In the case where L1represents a group which is cleaved from X1by heat or infrared exposure, X1is preferably a sulfur atom. 11 is a single bond.

[0296] X 11 and X 12 Each of L1and L2independently represents a single bond or an alkylene group, and is preferably a single bond or an alkylene group having 1 to 5 carbon atoms, and more preferably a single bond or an alkylene group having 1 to 3 carbon atoms.

[0297] L1represents a hydrocarbon group, a heteroaryl group or a group which is cleaved from X1by heat or infrared exposure, and from the viewpoint of print durability, it is preferably a hydrocarbon group or a heteroaryl group, and more preferably an aryl group or a heteroaryl group, and still more preferably a heteroaryl group.

[0298] Further, from the viewpoint of developing image contrast by infrared exposure, L1is preferably a group which is cleaved from X1by heat or infrared exposure.

[0299] The group which is cleaved from X1by heat or infrared exposure will be described later.

[0300] R 17 and R 18 Each of R1and R2independently represents a hydrogen atom, an alkyl group, an aryl group or an alkenyl group. Each of R1and R2is preferably an alkyl group or an aryl group, more preferably an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and still more preferably an alkyl group having 1 to 12 carbon atoms.

[0301] R 19 represents a hydrocarbon group or a heteroaryl group, and is preferably an aryl group or a heteroaryl group, and more preferably a heteroaryl group.

[0302] As the heteroaryl group in L1and R 19 , there is no particular limitation, but the following groups are preferably selected.

[0303] [Chemical Formula 3]

[0304]

[0305] R 31 represents a hydrogen atom, an alkyl group, an aryl group or an alkenyl group.

[0306] R 32 to R 34 Each of R1and R2independently represents a hydrogen atom, an alkyl group, an aryl group or an alkenyl group. Each of R1and R2is preferably an alkyl group or an aryl group, more preferably an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and still more preferably an alkyl group having 1 to 12 carbon atoms.

[0307] n1 to n3 each independently represent an integer of 1 to 4. In the case where n1 to n3 are an integer of 2 to 4, a plurality of R 32 , a plurality of R 33 , a plurality of R 34 may be the same, respectively, and also can be different.

[0308] * indicates a bonding position.

[0309] R1 to R 10 , R0 and R 31 to R 34 The alkyl group in R1 to R 10 , R0 and R 18 , R 19 , R0 and R 31 to R 34 is preferably an alkyl group having 1 to 30 carbon atoms, more preferably an alkyl group having 1 to 15 carbon atoms, further preferably an alkyl group having 1 to 12 carbon atoms, and particularly preferably an alkyl group having 1 to 10 carbon atoms. The above alkyl group can be linear, can have a branched chain, and can have a ring structure.

[0310] Specific examples include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a undecyl group, a dodecyl group, a tridecyl group, a hexadecyl group, an octadecyl group, an eicosyl group, an isopropyl group, an isobutyl group, a sec-butyl group, a t-butyl group, an isopentyl group, a neopentyl group, a 1-methylbutyl group, an isohexyl group, a 2-ethylhexyl group, a 2-methylhexyl group, a cyclohexyl group, a cyclopentyl group, and a 2-norbornyl group.

[0311] Among these alkyl groups, a methyl group, an ethyl group, a propyl group, or a butyl group is particularly preferable.

[0312] The above alkyl group can have a substituent. Examples of the substituent include an alkoxy group, an aryloxy group, an amino group, an alkylthio group, an arylthio group, a halogen atom, a carboxyl group, a carboxylate group, a sulfo group, a sulfonate group, an alkoxycarbonyl group, an aryloxycarbonyl group, and a group formed by combining these groups.

[0313] The aryl group in R7, R8, R9, R 10 , R 18 , R 19 , R0 and R 31 to R 34 is preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 20 carbon atoms, and further preferably an aryl group having 6 to 12 carbon atoms.

[0314] The above aryl group can have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, an aryloxy group, an amino group, an alkylthio group, an arylthio group, a halogen atom, a carboxyl group, a carboxylate group, a sulfo group, a sulfonate group, an alkoxycarbonyl group, an aryloxycarbonyl group, and a group formed by combining these groups.

[0315] As the above-mentioned aryl group, specifically, for example, a phenyl group, a naphthyl group, a p-tolyl group, a p-chlorophenyl group, a p-fluorophenyl group, a p-methoxyphenyl group, a p-dimethylaminophenyl group, a p-methylthiophenyl group, a p-phenylthiophenyl group, and the like can be mentioned.

[0316] Among these aryl groups, a phenyl group, a p-methoxyphenyl group, a p-dimethylaminophenyl group, and a naphthyl group are preferred.

[0317] R 31 ~ R 34 The alkenyl group in the above-mentioned formula (1) is preferably an alkenyl group having 2 to 30 carbon atoms, more preferably an alkenyl group having 2 to 15 carbon atoms, and further more preferably an alkenyl group having 2 to 10 carbon atoms. The above-mentioned alkyl group can be linear, can have a branched chain, and can have a ring structure.

[0318] Further, the above-mentioned alkenyl group can have a substituent. As examples of the substituent, an alkoxy group, an aryloxy group, an amino group, an alkylthio group, an arylthio group, a halogen atom, a carboxyl group, a carboxylate group, a sulfo group, a sulfonate group, an alkoxycarbonyl group, an aryloxycarbonyl group, and a group formed by combining them, and the like can be mentioned.

[0319] As the above-mentioned alkenyl group, specifically, for example, an ethenyl group, a propenyl group, a butenyl group, a pentenyl group, a hexenyl group, a cyclohexenyl group, and the like can be mentioned.

[0320] Among these alkenyl groups, an ethenyl group and a propenyl group are preferred.

[0321] R1and R2preferably join to form a ring.

[0322] In the case where R1and R2join to form a ring, the preferred number of ring members is preferably a 5- or 6-membered ring, and more preferably a 6-membered ring. Further, the ring formed by R1and R2joining is preferably a hydrocarbon ring which can have an ethylenic unsaturated bond.

[0323] Y1and Y2independently represent an oxygen atom, a sulfur atom, -NR0-, or a dialkylmethylene group, preferably -NR0- or a dialkylmethylene group, and more preferably a dialkylmethylene group.

[0324] R0represents a hydrogen atom, an alkyl group, or an aryl group, and is preferably an alkyl group.

[0325] R7and R8are preferably the same group.

[0326] Further, R7and R8independently are preferably a linear alkyl group or an alkyl group having a sulfonate group at the terminal end, and more preferably a methyl group, an ethyl group, or a butyl group having a sulfonate group at the terminal end.

[0327] Further, the counter cation of the above-mentioned sulfonate group can be the cation on the nitrogen atom in formula (1), and can also be an alkali metal cation or an alkaline earth metal cation.

[0328] Further, from the viewpoint of improving the water solubility of the compound represented by formula (1), R7and R8are each independently preferably an alkyl group having an anionic structure, more preferably an alkyl group having a carboxylate group or a sulfonate group, and further preferably an alkyl group having a sulfonate group at the terminal.

[0329] R3to R6each independently represent a hydrogen atom or an alkyl group, and are preferably a hydrogen atom.

[0330] Za represents a counter ion for neutralizing a charge, and in the case of representing an anion species, sulfonate ions, carboxylate ions, tetrafluoroborate ions, tetraphenylborate ions, hexafluorophosphate ions, perchlorate ions, sulfonamide anions, sulfonimide anions, and the like can be given. In the case of representing a cation species, alkali metal ions, alkaline earth metal ions, ammonium ions, pyridinium ions, or sulfonium ions are preferred, and sodium ions, potassium ions, ammonium ions, pyridinium ions, or sulfonium ions are more preferred, and sodium ions, potassium ions, or ammonium ions are further preferred, and sodium ions, potassium ions, or trialkylammonium ions are particularly preferred.

[0331] Za is preferably an organic anion containing a carbon atom, and is more preferably a sulfonate ion, a carboxylate ion, a sulfonamide anion, or a sulfonimide anion, and is further preferably a sulfonamide anion or a sulfonimide anion, and is particularly preferably a sulfonimide anion.

[0332] R1to R8, R0, A1, Ar1, Ar2, Y1, and Y2may have an anionic structure or a cationic structure, and if R1to R8, R0, A1, Ar1, Ar2, Y1, and Y2are all electrically neutral groups, Za is a monovalent counter anion, but for example, in the case where R1to R8, R0, A1, Ar1, Ar2, Y1, and Y2have two or more anionic structures, Za can also be a counter cation.

[0333] Further, in formula (1), if the portion other than Za is electrically neutral, Za can be absent.

[0334] As the sulfonamide anion, an arylsulfonamide anion is preferred.

[0335] Further, as the sulfonimide anion, a diarylsulfonimide anion is preferred.

[0336] Specific examples of the sulfonamide anion or the sulfonimide anion are shown below, but the present application is not limited to these. In the specific examples below, Ph represents a phenyl group, Me represents a methyl group, and Et represents an ethyl group.

[0337] [Chemical Formula 4]

[0338]

[0339] From the viewpoints of image formability and color developability, the group that is cleaved from the bond with X1by heat or infrared exposure is preferably a group represented by any one of the following Formulae 1-1 to 1-7, and more preferably a group represented by any one of the following Formulae 1-1 to 1-3.

[0340] [Chemical Formula 5]

[0341]

[0342] In Formulae 1-1 to 1-7, • indicates a bonding site with X1in Formula (1), R 10 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, -OR 14 , -NR 15 R 16 , or -SR 17 , R 11 each independently represents a hydrogen atom, an alkyl group, or an aryl group, R 12 represents an aryl group, -OR 14 , -NR 15 R 16 , -SR 17 , -C(=O)R 18 , -OC(=O)R 18 , or a halogen atom, R 13 represents an aryl group, an alkenyl group, an alkoxy group, or an onium group, R 14 to R 17 each independently represents a hydrogen atom, an alkyl group, or an aryl group, R 18 each independently represents an alkyl group, an aryl group, -OR 14 , -NR 158 R 16 , or -SR 17 , Z 1 represents a counter ion that neutralizes a charge.

[0343] R 10 , R 11 , and R 14 to R 18 are alkyl groups, the preferable modes thereof are the same as those of the alkyl groups in R1to R 10 and R0.

[0344] R 10 , and the alkenyl group in R 13 has a carbon atom number of preferably 1 to 30, more preferably 1 to 15, and further preferably 1 to 10.

[0345] R 10 to R 18 are aryl groups, the preferable modes thereof are the same as those of the aryl groups in R0.

[0346] From the perspective of image formation and color rendering, R in Equation 1-1 10 Preferably alkyl, alkenyl, aryl, or -OR 14 -NR 15 R 16 or -SR 17 More preferably alkyl, -OR 14 -NR 15 R 16 or -SR 17 More preferably alkyl or -OR 14 Especially preferred is -OR 14 .

[0347] Furthermore, R in Equation 1-1 10 When the alkyl group is alkyl, it is preferably an alkyl group having an arylthio group or an alkoxycarbonyl group at the α position.

[0348] R in Equation 1-1 10 For -OR 14 In the case of R 14 Preferably, it is an alkyl group, more preferably an alkyl group having 1 to 8 carbon atoms, and even more preferably isopropyl or tert-butyl, especially tert-butyl.

[0349] From the perspective of image formation and color rendering, R in Equation 1-2 11 Hydrogen atoms are preferred.

[0350] Furthermore, from the perspective of image formation and color rendering, R in Equation 1-2 12 The preferred option is -C(=0)OR 14 -OC(=O)OR 14 Or halogen atoms, more preferably -C(=O)OR 14 or -OC(=O)OR 14 In Equation 1-2, R 12 -C(=O)OR 14 or -OC(=O)OR 14 In the case of R 14 Alkyl groups are preferred.

[0351] From the perspective of image formation and color rendering, R in Equation 1-3 11 Each is preferably a hydrogen atom or an alkyl group, and at least one R in formulas 1-3 11 More preferably, it is an alkyl group.

[0352] Furthermore, R 11 The alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, and more preferably an alkyl group having 3 to 10 carbon atoms.

[0353] Moreover, R 11The alkyl group is preferably a branched alkyl or cycloalkyl group, more preferably a secondary or tertiary alkyl group, or a cycloalkyl group, and even more preferably isopropyl, cyclopentyl, cyclohexyl or tert-butyl.

[0354] Furthermore, from the perspective of image formation and color rendering, R in Equations 1-3 13 Preferably, it is aryl, alkoxy, or onnyl, more preferably p-dimethylaminophenyl or pyridinium, and even more preferably pyridinium.

[0355] As R 13 Examples of onnnyl groups include pyridinium, ammonium, and sulfonium. Onnnyl groups can have substituents. Examples of substituents include alkyl, alkoxy, aryloxy, amino, alkylthio, arylthio, halogen, carboxyl, sulfonyl, alkoxycarbonyl, aryloxycarbonyl, and combinations thereof, but alkyl, aryl, and combinations thereof are preferred.

[0356] Preferably, pyridinium group is used; more preferably, N-alkyl-3-pyridinium group, N-benzyl-3-pyridinium group, N-(alkoxypolyalkoxyalkyl)-3-pyridinium group, N-alkoxycarbonylmethyl-3-pyridinium group, N-alkyl-4-pyridinium group, N-benzyl-4-pyridinium group, N-(alkoxypolyalkoxyalkyl)-4-pyridinium group, and N-alkoxycarbonylmethyl-4-pyridinium group are used. -Pyridinium or N-alkyl-3,5-dimethyl-4-pyridinium, more preferably N-alkyl-3-pyridinium or N-alkyl-4-pyridinium, particularly preferably N-methyl-3-pyridinium, N-octyl-3-pyridinium, N-methyl-4-pyridinium or N-octyl-4-pyridinium, most preferably N-octyl-3-pyridinium or N-octyl-4-pyridinium.

[0357] Furthermore, in R 13 In the case of a pyridinium group, counter anions include sulfonate ions, carboxylate ions, tetrafluoroborate ions, hexafluorophosphate ions, p-toluenesulfonate ions, perchlorate ions, etc., with p-toluenesulfonate ions or hexafluorophosphate ions being preferred.

[0358] From the perspective of image formation and color rendering, R in Equation 1-4 10 Preferably alkyl or aryl, more preferably 2 Rs 10 One of them is alkyl and the other is aryl.

[0359] From the perspective of image formation and color rendering, R in Equation 1-5 10 Preferably alkyl or aryl, more preferably aryl, and even more preferably p-methylphenyl.

[0360] From the perspective of image formation and color rendering, R in Equations 1-610 Each is preferably alkyl or aryl, more preferably methyl or phenyl.

[0361] From the perspective of image formation and color rendering, regarding Z in Equations 1-7 1 Any counterion that neutralizes the charge can be included in the above-mentioned Za as a whole compound.

[0362] Z 1 Preferably, it is a sulfonate ion, a carboxylate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, a p-toluenesulfonate ion, or a perchlorate ion, more preferably a p-toluenesulfonate ion or a hexafluorophosphate ion.

[0363] Furthermore, the groups that break the bond with X1 through heat or infrared exposure are particularly preferably groups represented by formulas 1-8.

[0364] [Chemical Formula 6]

[0365]

[0366] In Equations 1-8, · represents the bonding site with X1 in Equation (1), and R 19 and R 20 Each of these represents an alkyl group independently, and Za′ represents a counterion that neutralizes the charge.

[0367] The pyridinium ring in Formulas 1-8 and the R-containing ring 20 The bonding position of the hydrocarbon group is preferably at the 3 or 4 position of the pyridinium ring, more preferably at the 4 position of the pyridinium ring.

[0368] R 19 and R 20 The alkyl group can be straight-chain, branched, or cyclic.

[0369] Furthermore, the aforementioned alkyl group may have substituents, with alkoxy groups and terminal alkoxy polyalkoxide groups being preferred examples.

[0370] R 19 Preferably, it is an alkyl group having 1 to 12 carbon atoms, more preferably a straight-chain alkyl group having 1 to 12 carbon atoms, even more preferably a straight-chain alkyl group having 1 to 8 carbon atoms, and especially preferably methyl or n-octyl.

[0371] R 20 Preferably, it is an alkyl group having 1 to 8 carbon atoms, more preferably a branched alkyl group having 3 to 8 carbon atoms, and even more preferably isopropyl or tert-butyl, especially isopropyl.

[0372] Regarding Za′, any counterion that neutralizes the charge can be included in the aforementioned Za as a whole compound.

[0373] Za' is preferably a sulfonate ion, a carboxylate ion, a tetrafluoroborate ion, a hexafluorophosphate ion, a p-toluenesulfonate ion, or a perchlorate ion, more preferably a p-toluenesulfonate ion or a hexafluorophosphate ion.

[0374] Hereinafter, as specific examples of the specific infrared absorber, the following can be given: the core structures IR-1 to IR-17, IR-20 to IR-37, the counter anions A-1 to A-4, and the counter cations C-1 to C-3, but the present application is not limited thereto.

[0375] Further, with respect to the core structure, the value of HOMO is shown.

[0376] In addition, specific examples of the specific infrared absorber are compounds each of which is obtained by combining one of the core structures IR-1 to IR-15, IR-24 to IR-37 and one of the counter anions A-1 to A-4, and compounds each of which is obtained by combining one of the core structures IR-20 to IR-23 and one of the counter cations C-1 to C-3.

[0377] The core structures IR-16 and IR-17 do not have a counter anion.

[0378] [Chemical Formula 7]

[0379]

[0380] [Chemical Formula 8]

[0381]

[0382] [Chemical Formula 9]

[0383]

[0384] [Chemical Formula 10]

[0385]

[0386] [Chemical Formula 11]

[0387]

[0388] [Chemical Formula 12]

[0389]

[0390] The HOMO of the specific infrared absorber is -5.43 eV or less. From the viewpoint of inhibiting the temporal degradation of the specific infrared absorber, it is preferable that the specific infrared absorber have a lower HOMO energy level.

[0391] The HOMO of the specific infrared absorber is more preferably -5.45 eV or less, and further preferably -5.47 eV or less.

[0392] The lower limit of the HOMO of the specific infrared absorber is not particularly limited, but is usually -5.60 eV.

[0393] The specific infrared absorber can be a commercially available product, and can be produced by referring to a publicly known production method. For example, in the case where the specific infrared absorber is a compound represented by formula (1), the production method is not particularly limited, and can be produced by referring to a publicly known production method of a cyanine dye. Also, the method described in International Publication No. 2016 / 027886 can be preferably used.

[0394] The specific infrared absorber can be used alone or in combination of two or more.

[0395] The content of the specific infrared absorber in the specific structure layer is preferably 0.05 to 30% by mass, more preferably 0.1 to 20% by mass, and further preferably 0.2 to 10% by mass, in the total solid content of the specific structure layer.

[0396] The specific structure layer is at least one layer containing the specific infrared absorber, and therefore, in the case where the layer constituting the lithographic printing plate precursor, for example, the image-recording layer, the undercoat layer, or the protective layer, contains the specific infrared absorber, the layer corresponds to the specific structure layer.

[0397] As a preferred mode, the at least one layer containing the specific infrared absorber is the image-recording layer.

[0398] As a preferred mode, the at least one layer containing the specific infrared absorber is the protective layer.

[0399] The at least one layer containing the specific infrared absorber can be one layer or two or more layers.

[0400] In the lithographic printing plate precursor constituting the laminate according to the present application, the arithmetic mean height Sa of the outermost layer surface of at least one of the side of the at least one layer containing the above-described infrared absorber with the above-described support as a reference and the side opposite thereto is 0.3 μm or more and 20 μm or less.

[0401] The at least one layer containing the above-described infrared absorber is the above-described specific structure layer.

[0402] As one mode, in the lithographic printing plate precursor constituting the laminate according to the present application, the arithmetic mean height Sa of the outermost layer surface of the side of the at least one layer containing the above-described infrared absorber with the above-described support as a reference (hereinafter, sometimes referred to as "A side") is 0.3 μm or more and 20 μm or less.

[0403] As another aspect, in the lithographic printing plate precursor which constitutes the laminate according to the present application, the arithmetic mean height Sa of the outermost layer surface on the side opposite to the side of the at least one layer containing the above-described infrared absorber with reference to the above-described support is 0.3 μm or more and 20 μm or less.

[0404] As another aspect, in the lithographic printing plate precursor which constitutes the laminate according to the present application, the arithmetic mean height Sa of the outermost layer surface on the side opposite to the side of the at least one layer containing the above-described infrared absorber with reference to the above-described support is 0.3 μm or more and 20 μm or less.

[0405] With respect to the outermost layer surface on the side opposite to the side of the specific structure layer with reference to the support, in the case where a backcoat layer is present on the opposite side thereof, it is the surface of the backcoat layer, and in the case where no layer is present on the opposite side thereof, it is the surface of the support.

[0406] For example, in the case where the protrusions described later are formed, the lithographic printing plate precursor can be such that the above-described backcoat layer is the outermost layer, and a plurality of protrusions containing a high molecular compound are present on the above-described backcoat layer, or such that the above-described support is the outermost layer, and a plurality of protrusions containing a high molecular compound are present on the above-described support.

[0407] In the case where the image recording layer or the protective layer is the outermost layer, the outermost layer surface on the side of the specific structure layer with reference to the support is the surface of the image recording layer or the surface of the protective layer.

[0408] For example, in the case where the protrusions described later are formed, the lithographic printing plate precursor can be such that the above-described image recording layer or the protective layer is the outermost layer, and a plurality of protrusions containing a high molecular compound are present on the above-described image recording layer or the protective layer.

[0409] The arithmetic mean height Sa of the outermost layer surface on the side opposite to the side of the specific structure layer with reference to the support is more preferably 0.5 to 10 μm, and further preferably 0.5 to 7 μm.

[0410] The arithmetic mean height Sa of the outermost layer surface on the side of the specific structure layer with reference to the support is more preferably 0.5 to 10 μm, and further preferably 0.5 to 7 μm.

[0411] The arithmetic average height Sa on the outermost surface is measured in accordance with the method described in ISO 25178. That is, using a micro-mapper MM3200-M100 manufactured by Ryoka Systems Inc., the measurement is performed at three or more places from the same sample, and the average thereof is taken as the arithmetic average height Sa. As for the measurement range, a 1 cm x 1 cm range randomly selected from the sample surface is measured.

[0412] In order to achieve the necessary condition that the arithmetic average height Sa of the outermost surface is 0.3 to 20 μm, it is preferable that the outermost layer has a shape having a concave-convex.

[0413] Specifically, for example, there are a mode in which the outermost layer contains particles having an average particle diameter of 0.5 to 20 μm (Mode 1) and a mode in which the outermost layer has a plurality of protrusions containing a high molecular compound as a main component (Mode 2). Here, the main component means a component having the highest ratio (mass %).

[0414] As Mode 1, there is a mode in which the layer adjacent to the outermost layer contains particles having an average particle diameter of 0.5 to 20 μm.

[0415] In Mode 1, the particles having an average particle diameter of 0.5 to 20 μm are not particularly limited, but it is preferable that at least one particle selected from organic resin particles and inorganic particles.

[0416] As the organic resin particles, it is preferable to select particles of synthetic resins including poly(meth)acrylate, polystyrene and its derivatives, polyamide, polyimide, low-density polyethylene, high-density polyethylene, polyolefins such as polypropylene, polyurethane, polyurea, polyesters, and particles of natural high molecules including chitin, chitosan, cellulose, crosslinked starch, crosslinked cellulose, and the like.

[0417] Among them, the synthetic resin particles have advantages that the particle size is easily controlled, the desired surface properties are easily controlled by surface modification, and the like.

[0418] As for the method of producing the organic resin particles, micronization based on a crushing method is also possible with a relatively hard resin such as polymethyl methacrylate (PMMA), but from the viewpoint of easy controllability and accuracy of the particle diameter, it is preferable to adopt a method of synthesizing particles by an emulsion suspension polymerization method.

[0419] The method of producing the organic resin particles is described in detail in "Ultrafine Particles and Materials", edited by the Japan Society of Materials Science, Shokabo, 1993, "Manufacture and Application of Particles / Powders", edited by Haruma Kawaguchi, CMC Publishing, 2005, and the like.

[0420] The organic resin particles can also be obtained as commercially available products, such as crosslinked acrylic resins MX-40T, MX-80H3wT, MX-150, MX-180TA, MX-300, MX-500, MX-1000, MX-1500H, MR-2HG, MR-7HG, MR-10HG, MR-3GSN, MR-5GSN, MR-7G, MR-10G, MR-5C, MR-7GC, styrene resin SX-350H, SX-500H manufactured by Soken Chemical & Engineering Co., Ltd., acrylic resins MBX-5, MBX-8, MBX-12, MBX-15, MBX-20, MB20X-5, MB30X-5, MB30X-8, MB30X-20, SBX-6, SBX-8, SBX-12, SBX-17, SSX-101, SSX-102, SSX-104, SSX-105 manufactured by Sekisui Plastics Co., Ltd., polyolefin resins manufactured by Mitsui Chemicals, Inc., CHEMIPEARL W100, W200, W300, W308, W310, W400, W401, W405, W410, W500, WF640, W700, W800, W900, W950, WP100, ART PEARL J-6PE, J-7PS manufactured by Negami Chemical Industrial co., ltd., and the like.

[0421] As the inorganic particles, there can be mentioned silica, alumina, zirconia, titania, carbon black, graphite, BaSO4, ZnS, MgCO3, CaCO3, ZnO, CaO, WS2, MoS2, MgO, SnO2, α-Fe2O3, α-FeOOH, SiC, CeO2, BN, SiN, MoC, BC, WC, titanium carbide, corundum, artificial diamond, garnet, silica stone, weathered silica stone (Triboli), diatomaceous earth, dolomite, and the like.

[0422] The above particles are preferably particles having a hydrophilic surface. The particles having a hydrophilic surface include organic resin particles having a hydrophilic surface and inorganic particles having a hydrophilic surface.

[0423] The organic resin particles having a hydrophilic surface are preferably organic resin particles coated with at least one inorganic compound selected from the group consisting of silica, alumina, titania, and zirconia, and particularly preferably organic resin particles coated with silica.

[0424] The organic resin constituting the organic resin particle having a hydrophilic surface is preferably at least one resin selected from the group consisting of a polyacrylic resin, a polyurethane resin, a polystyrene resin, a polyester resin, an epoxy resin, a phenol resin, and a melamine resin.

[0425] Hereinafter, the organic resin particle having a hydrophilic surface will be described in detail taking an organic resin particle coated with silica (hereinafter, also referred to as "organic resin particle coated with silica") as an example, but the organic resin particle having a hydrophilic surface is not limited thereto.

[0426] The organic resin particle coated with silica is a particle in which a particle composed of an organic resin is surface-coated with silica. The organic resin particle constituting the core is preferably not softened or tacky due to humidity or temperature in the air.

[0427] As the organic resin constituting the organic resin particle in the organic resin particle coated with silica, for example, a polyacrylic resin, a polyurethane resin, a polystyrene resin, a polyester resin, an epoxy resin, a phenol resin, a melamine resin, or the like can be given.

[0428] As the material forming the silica layer coating the surface of the organic resin particle coated with silica, a compound having an alkoxysilyl group such as a condensate of an alkoxysiloxane-based compound is preferable, and a siloxane-based material is particularly preferable, and specifically, a silica particle such as silica sol, colloidal silica, silica nanoparticle, or the like is preferable.

[0429] The structure of the organic resin particle coated with silica can be a structure in which a silica particle is adhered to the surface of the organic resin particle as a solid component, or a structure in which a siloxane-based compound layer is formed on the surface of the organic resin particle by condensation reaction of an alkoxysiloxane-based compound.

[0430] The silica does not necessarily coat the entire area of the surface of the organic resin particle, and it is preferable that the surface be coated with silica in an amount of 0.5% by mass or more relative to the total mass of the organic resin particle. That is, silica is present in at least a part of the surface of the organic resin particle, whereby an increase in affinity with a water-soluble polymer such as polyvinyl alcohol (PVA) coexisting on the surface of the organic particle can be achieved, and peeling of the particle can be suppressed even when subjected to external stress, and excellent scratch resistance and ease of peeling when laminated without a liner paper can be maintained. Therefore, "coated with silica" also includes a state in which silica is present in at least a part of the surface of the organic resin particle as such.

[0431] The surface coating state of the silica can be confirmed by morphological observation using a scanning electron microscope (SEM) or the like. Also, the coating amount of the silica can be confirmed by detecting Si atoms using elemental analysis such as fluorescent X-ray analysis, and calculating the amount of silica present in the Si atoms.

[0432] The method for producing the organic resin particles coated with silica is not particularly limited, and can be a method in which a silica particle or a silica precursor compound is co-presented with a monomer component that is a raw material of the organic resin particle to form an organic resin particle while forming a silica surface coating layer, and can also be a method in which a silica particle is physically adhered to the surface after the formation of the organic resin particle, and then immobilized.

[0433] Hereinafter, an example of the method for producing the organic resin particles coated with silica will be described. First, a suspension liquid in which silica and a raw resin (more specifically, a monomer that can be suspension-polymerized, a prepolymer or a resin liquid that can be suspension-crosslinked, or the like, which constitutes the above-mentioned organic resin, is prepared by adding the silica and the raw resin to water containing a suspension stabilizer appropriately selected from among water-soluble polymers such as polyvinyl alcohol, methyl cellulose, and polyacrylic acid, or inorganic suspending agents such as calcium phosphate and calcium carbonate, and stirring and mixing. At this time, by adjusting the type of the suspension stabilizer, the concentration thereof, the stirring speed, and the like, a suspension liquid having a target particle diameter can be formed. Next, the suspension liquid is warmed to initiate a reaction, and the raw resin is suspension-polymerized or suspension-crosslinked to generate resin particles. At this time, the co-presented silica is immobilized to the resin particles that are cured by the polymerization or crosslinking reaction, and in particular, is immobilized in the vicinity of the surface of the resin particles due to the physical properties thereof. Then, the suspension liquid is subjected to solid-liquid separation, and the suspension stabilizer adhering to the particles is removed by washing and drying. In this way, the organic resin particles coated with silica in which silica is immobilized, and which are approximately spherical and have a desired particle diameter, can be obtained.

[0434] In this way, the organic resin particles coated with silica having a desired particle diameter can be obtained by controlling the conditions at the time of suspension polymerization or suspension crosslinking, and also, after the production of the organic resin particles coated with silica without such strict control, the organic resin particles coated with silica having a desired size can be obtained by a screen filtration method or the like.

[0435] As to the amount of addition of the raw materials in the mixture at the time of manufacturing the organic particles coated with silica by the above method, etc., for example, the following manner is preferably selected: in the case where the total amount of the raw material resin and silica is 100 parts by mass, first, 0.1 to 20 parts by mass of a suspension stabilizer is added to 200 to 800 parts by mass of water as a dispersion medium, and is sufficiently dissolved or dispersed, the mixture of the above 100 parts by mass of the raw material resin and silica is put into the liquid, and stirring is performed while adjusting the stirring speed in a manner that the dispersed particles become a predetermined particle size, and after the particle size adjustment, the liquid temperature is raised to 30 to 90°C and the reaction is performed for 1 to 8 hours.

[0436] As to the method of manufacturing the organic resin particles coated with silica, the above method is one example thereof, and for example, the organic resin particles coated with silica obtained by the methods described in detail in Japanese Patent Application Publication No. 2002-327036, Japanese Patent Application Publication No. 2002-173410, Japanese Patent Application Publication No. 2004-307837, Japanese Patent Application Publication No. 2006-38246, and the like are preferably used in the present application.

[0437] Further, the organic resin particles coated with silica can also be obtained as a commercial product. Specifically, as the silica / melamine composite particles, OPTBEADS 2000M, OPTBEADS 3500M, OPTBEADS 6500M, OPTBEADS 10500M, OPTBEADS 3500S, OPTBEADS 6500S manufactured by Nissan Chemical Industries, Ltd. can be mentioned. As the silica / acrylic acid composite particles, ART PEARL G-200 transparent, ART PEARL G-400 transparent, ART PEARL G-800 transparent, ART PEARL GR-400 transparent, ART PEARL GR-600 transparent, ART PEARL GR-800 transparent, ART PEARL J-7P manufactured by Negami Chemical Industrial Co., Ltd. can be mentioned. As the silica / urethane composite particles, ART PEARL C-400 transparent, C-800 transparent, P-800T, U-600T, U-800T, CF-600T, CF-800T manufactured by Negami Chemical Industrial Co., Ltd. and Dynamic Beads CN5070D, Dumpla Coat THU manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd. can be mentioned.

[0438] The above describes the organic resin particles coated with silica, but the same can be applied to organic resin particles coated with alumina, titania, or zirconia by replacing silica with alumina, titania, or zirconia.

[0439] The shape of the above particles is preferably a spherical shape, but can be a flat plate shape or a so-called spindle shape that is elliptical in a projection view.

[0440] In Mode 1, the average particle diameter of the above particles is preferably 0.5 to 10 μm, more preferably 1.0 to 10 μm, and further preferably 2.0 to 7.0 μm.

[0441] The average particle diameter of the particles refers to the volume average particle diameter, and the volume average particle diameter is measured by a laser diffraction / scattering particle size distribution meter. Specifically, the measurement is performed using a particle size distribution measuring device "micro-trac MT-3300II" (manufactured by Nikkiso Co., LTD.), and the median particle diameter (D50) obtained at this time is used as the average particle diameter.

[0442] For other particles, the average particle diameter is measured by the above measurement method unless otherwise specified.

[0443] In Mode 1, the in-plane density of particles having an average particle diameter of 0.5 to 20 μm is preferably 10,000 pieces / mm 2 The in-plane density is more preferably 100 to 5,000 pieces / mm 2 and further preferably 100 to 3,000 pieces / mm 2 .

[0444] The in-plane density can be confirmed by observing the surface of the lithographic printing plate precursor using a scanning electron microscope (SEM). Specifically, the number of particles can be counted by observing 5 places on the surface of the lithographic printing plate precursor using a scanning electron microscope (SEM), converting the number of particles per square millimeter of the observed field of view area, and calculating the average value.

[0445] Among the particles having an average particle diameter of 0.5 to 20 μm, in addition to the above particles, there are particles having an average particle diameter of 0.5 to 20 μm among the polymer particles that are the binder described later.

[0446] The outermost layer on the side opposite to the side having the specific structure layer preferably contains a binder in addition to the particles having an average particle diameter of 0.5 to 20 μm.

[0447] As the binder, at least one kind selected from the group consisting of phenol formaldehyde resins such as phenol formaldehyde resin, m-cresol formaldehyde resin, p-cresol formaldehyde resin, m / p-mixed cresol formaldehyde resin, phenol / cresol (either m, p or m / p-mixed) mixed formaldehyde resin, pyrogallol, acetone resin, epoxy resin, saturated copolymer polyester resin, phenoxy resin, polyvinyl acetal resin, vinylidene dichloride copolymer resin, polybutene, polybutadiene, polyamide, unsaturated copolymer polyester resin, polyurethane, polyurea, polyimide, polysiloxane, polycarbonate, epoxy resin, chlorinated polyethylene, aldehyde condensation resin of alkyl phenol, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyacrylate, carboxyethylene polymer, acrylic resin copolymer resin, hydroxyl cellulose, methylol cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, cellulose acetate, methyl cellulose, carboxymethyl cellulose is preferable. In order to prevent the concern of dissolution in the dampening solution at on-press development, a non-water soluble resin is preferable.

[0448] Further, as the above-mentioned binder, at least one kind selected from the group consisting of polyurethane, acrylic resin, polystyrene and polyethylene is preferable.

[0449] Further, in the above-mentioned mode 1, the above-mentioned particle and the above-mentioned binder each independently contain at least one kind selected from the group consisting of polyurethane, acrylic resin, polystyrene and polyethylene.

[0450] The outermost layer on the side opposite to the side having the specific structure layer can contain other components in addition to the above-mentioned particle and the binder. As the other components, well-known additives such as surfactants and the like can be mentioned.

[0451] The thickness of the outermost layer on the side opposite to the side having the specific structure layer is preferably 0.5 to 10 μm, more preferably 0.5 to 5 μm, and further preferably 0.5 to 3 μm.

[0452] As the high molecular compound constituting the plurality of protrusions containing a high molecular compound as a main component in the mode 2, at least one kind of high molecular compound selected from the group consisting of phenol formaldehyde resins, m-cresol formaldehyde resins, p-cresol formaldehyde resins, m / p-mixed cresol formaldehyde resins, phenol / cresol (any one of m, p or m / p-mixed) mixed formaldehyde resins, and the like novolak resins or resols, pyrogallol acetone resins, epoxy resins, saturated copolymer polyester resins, phenoxy resins, polyvinyl acetal resins, vinylidene chloride copolymer resins, polybutene, polybutadiene, polyamide, unsaturated copolymer polyester resins, polyurethane, polyurea, polyimide, polysiloxane, polycarbonate, epoxy resins, chlorinated polyethylene, aldehyde condensation resins of alkyl phenols, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyacrylate, carboxyvinyl polymer, acrylic copolymer resin, hydroxyl cellulose, methylol cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, cellulose acetate, methyl cellulose, carboxymethyl cellulose is preferable.

[0453] Among them, from the viewpoint that the developability is excellent even in the case where the detached protrusions move to the image recording layer, a water-soluble high molecule is more preferable. Specifically, for example, polyacrylate, carboxyvinyl polymer, acrylic copolymer resin, carboxy cellulose, methylol cellulose, polyvinyl alcohol, modified polyvinyl alcohol, polyvinyl pyrrolidone, cellulose acetate, methyl cellulose, carboxymethyl cellulose and the like can be mentioned.

[0454] As the modified polyvinyl alcohol, an acid-modified polyvinyl alcohol having a carboxyl group or a sulfo group can be preferably used. Specifically, the modified polyvinyl alcohol described in Japanese Patent Application Publication No. 2005-250216 and Japanese Patent Application Publication No. 2006-259137 is preferable.

[0455] The shape and height of the protrusions are not particularly limited, but the arithmetic mean height Sa is preferably 0.3 to 20 μm.

[0456] As the method of forming the stripe-shaped protrusions (stripe coating film), there is no particular limitation, but it can be easily formed by coating a composition containing at least one selected from the group consisting of particles and high molecular compounds by at least one selected from the group consisting of bar coating method, inkjet printing method, gravure printing method, screen printing method, spray coating method and slit die coating method.

[0457] As the method of forming the point-shaped protrusions (dot coating film), there is no particular limitation, but it can be easily formed by coating a composition containing at least one selected from the group consisting of particles and high molecular compounds by at least one selected from the group consisting of spray coating method, inkjet printing method and screen printing method.

[0458] As the method of forming the protrusions in a broken line shape (broken line coating film), there is no particular limitation, but it can be easily formed by applying a composition containing at least one selected from the group consisting of particles and a high molecular compound by at least one selected from the group consisting of an inkjet printing method and a screen printing method.

[0459] As the binder contained in the outermost layer in the method 2, the same high molecular compound as contained in the protrusions can be mentioned, and the preferable method is also the same.

[0460] In the method 2, from the viewpoint of preventing the protrusions from being detached, it is preferable that the binder contained in the outermost layer and the high molecular compound contained in the protrusions contain the same kind of resin. Here, the same kind of resin means that the resin kind is the same, such as polyurethane, acrylic resin, polystyrene, polyethylene, and all the structural units in the resin do not need to be the same.

[0461] As one method, the above-mentioned image recording layer preferably contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

[0462] Also, the above-mentioned image recording layer preferably contains at least two kinds of particles having an average particle diameter of 0.5 μm or more and 20 μm or less and different from each other in the average particle diameter.

[0463] As another method, the above-mentioned protective layer preferably contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

[0464] As another method, the outermost layer on the side opposite to the side having at least one layer containing the above-mentioned infrared absorbing agent with reference to the support preferably contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

[0465] [Planographic Printing Plate Precursor]

[0466] Hereinafter, one method of the planographic printing plate precursor which constitutes the laminate of the planographic printing plate precursor according to the present application will be described.

[0467] The planographic printing plate precursor has an image recording layer on the above-mentioned hydrophilic support.

[0468] [Image Recording Layer]

[0469] According to one preferable method of the image recording layer in the planographic printing plate precursor, the image recording layer contains a polymerization initiator, a polymerizable compound, and a high molecular compound. The image recording layer preferably further contains an infrared absorbing agent, a chain transfer agent.

[0470] According to another preferable method of the image recording layer, the image recording layer contains heat-fusible particles and a binder polymer. The image recording layer preferably further contains an infrared absorbing agent.

[0471] (polymerization initiator)

[0472] The polymerization initiator is a compound that generates a polymerization initiator species such as a radical or a cation by the energy of light, heat, or both, and can be appropriately selected and used from publicly known thermal polymerization initiators, compounds having a bond with a small bond dissociation energy, photopolymerization initiators, and the like.

[0473] As the polymerization initiator, an infrared photosensitive polymerization initiator is preferable. Also, as the polymerization initiator, a radical polymerization initiator is preferable. The radical polymerization initiator can be used in combination of two or more.

[0474] The radical polymerization initiator can be either one of an electron-accepting polymerization initiator and an electron-donating polymerization initiator.

[0475] <electron-accepting polymerization initiator>

[0476] As the electron-accepting polymerization initiator, for example, an organic halide, a carbonyl compound, an azo compound, an organic peroxide, a metallocene compound, an azide compound, a disulfone compound, an oxime ester compound, and an onium salt compound can be given.

[0477] As the organic halide, for example, a compound described in paragraphs 0022 to 0023 of Japanese Patent Application Publication No. 2008-195018 is preferable.

[0478] As the carbonyl compound, for example, a compound described in paragraph 0024 of Japanese Patent Application Publication No. 2008-195018 is preferable.

[0479] As the azo compound, for example, an azo compound described in Japanese Patent Application Publication No. H8-108621 and the like can be given.

[0480] As the organic peroxide, for example, a compound described in paragraph 0025 of Japanese Patent Application Publication No. 2008-195018 is preferable.

[0481] As the metallocene compound, for example, a compound described in paragraph 0026 of Japanese Patent Application Publication No. 2008-195018 is preferable.

[0482] As the azide compound, for example, a compound such as 2,6-bis(4-azidobenzylidene)-4-methylcyclohexanone can be given.

[0483] As the hexaarylbiimidazole compound, for example, a compound described in paragraph 0027 of Japanese Patent Application Publication No. 2008-195018 is preferable.

[0484] As the disulfone compound, for example, the compounds described in Japanese Patent Application Laid-Open No. 61-166544 and Japanese Patent Application Laid-Open No. 2002-328465 can be mentioned.

[0485] As the oxime ester compound, for example, the compounds described in paragraphs 0028 to 0030 of Japanese Patent Application Laid-Open No. 2008-195018 are preferable.

[0486] Among the electron-accepting polymerization initiators, as more preferable examples, onium salts such as iodonium salts, sulfonium salts and azinium salts can be mentioned. Iodonium salts and sulfonium salts are particularly preferable. Hereinafter, specific examples of iodonium salts and sulfonium salts will be shown, but the present application is not limited to these.

[0487] As examples of the iodonium salt, diphenyl iodonium salts are preferable, and diphenyl iodonium salts having an electron-donating group as a substituent, for example, diphenyl iodonium salts substituted with an alkyl group or an alkoxy group are particularly preferable, and non-symmetrical diphenyl iodonium salts are preferable. As specific examples, diphenyl iodonium hexafluorophosphate, 4-methoxyphenyl-4-(2-methylpropyl)phenyl iodonium hexafluorophosphate, 4-(2-methylpropyl)phenyl-p-tolyl iodonium hexafluorophosphate, 4-hexyloxyphenyl-2,4,6-trimethoxyphenyl iodonium hexafluorophosphate, 4-hexyloxyphenyl-2,4-diethoxyphenyl iodonium tetrafluoroborate, 4-octyloxyphenyl-2,4,6-trimethoxyphenyl iodonium 1-perfluorobutylsulfonate, 4-octyloxyphenyl-2,4,6-trimethoxyphenyl iodonium hexafluorophosphate, bis(4-tert-butylphenyl) iodonium tetraphenylborate can be mentioned.

[0488] As examples of the sulfonium salt, triaryl sulfonium salts are preferable, and triaryl sulfonium salts having an electron-withdrawing group as a substituent, for example, triaryl sulfonium salts in which at least a part of the groups on the aromatic ring are substituted with halogen atoms are particularly preferable, and triaryl sulfonium salts in which the total number of halogen atoms on the aromatic ring is four or more are further preferable. As specific examples, triphenyl sulfonium hexafluorophosphate, triphenyl sulfonium benzoylformate, bis(4-chlorophenyl)phenyl sulfonium benzoylformate, bis(4-chlorophenyl)-4-methylphenyl sulfonium tetrafluoroborate, tri(4-chlorophenyl) sulfonium 3,5-bis(methoxycarbonyl)benzenesulfonate, tri(4-chlorophenyl) sulfonium hexafluorophosphate, tri(2,4-dichlorophenyl) sulfonium hexafluorophosphate can be mentioned.

[0489] The electron-accepting polymerization initiator can be used alone or in combination of two or more.

[0490] The content of the electron-accepting polymerization initiator is preferably 0.1 to 50 mass%, more preferably 0.5 to 30 mass%, and further preferably 0.8 to 20 mass% in the total solid content of the image-recording layer.

[0491] <Electron-donating polymerization initiator>

[0492] Electron-donating polymerization initiators are useful for improving the printing durability of the lithographic printing plate produced from the lithographic printing plate precursor. As the electron-donating polymerization initiator, for example, the following five types can be given. (i) Alkyl or aryl acid radical type complex: It is considered that the carbon-hetero bond is oxidatively cleaved and an active radical is generated. Specifically, borate compounds and the like can be given. (ii) Amino acetic acid compounds: It is considered that an active radical is generated by cleavage of the C-X bond on the carbon adjacent to nitrogen by oxidation. As X, a hydrogen atom, a carboxyl group, a trimethylsilyl group, or a benzyl group is preferable. Specifically, N-phenyl glycine (a substituent can be present in the phenyl group), N-phenylimino diacetic acid (a substituent can be present in the phenyl group), and the like can be given. (iii) Sulfur-containing compounds: Compounds in which the nitrogen atom of the above-described amino acetic acid compounds is replaced with a sulfur atom are considered to generate an active radical by the same action. Specifically, phenylthio acetic acid (a substituent can be present in the phenyl group) and the like can be given. (iv) Tin-containing compounds: Compounds in which the nitrogen atom of the above-described amino acetic acid compounds is replaced with a tin atom can generate an active radical by the same action. (v) Sulfinate salts: An active radical can be generated by oxidation. Specifically, sodium aryl sulfinate and the like can be given.

[0493] Among the electron-donating polymerization initiators, a borate compound is preferable. As the borate compound, a tetraaryl borate compound or a monoalkyl triaryl borate compound is preferable, and from the viewpoint of compound stability, a tetraaryl borate compound is more preferable.

[0494] As the counter cation possessed by the borate compound, an alkali metal ion or a tetraalkyl ammonium ion is preferable, and a sodium ion, a potassium ion, or a tetrabutyl ammonium ion is more preferable.

[0495] As specific examples of the borate compound, the compounds shown below can be given. Among them, X c + represents a monovalent cation, an alkali metal ion or a tetraalkyl ammonium ion is preferable, and an alkali metal ion or a tetrabutyl ammonium ion is more preferable. Furthermore, Bu represents a n-butyl group.

[0496] [Chemical Formula 13]

[0497]

[0498] [Chemical Formula 14]

[0499]

[0500] [Chemical Formula 15]

[0501]

[0502] [Chemical Formula 16]

[0503]

[0504] The electron-donating polymerization initiator can be used alone or in combination of two or more.

[0505] The content of the electron-donating polymerization initiator is preferably 0.01 to 30% by mass, more preferably 0.05 to 25% by mass, and further preferably 0.1 to 20% by mass, in the total solid content of the image-recording layer.

[0506] (Polymerizable compound)

[0507] The polymerizable compound can be, for example, a radical polymerizable compound or a cationic polymerizable compound, and is preferably an addition polymerizable compound (ethylenically unsaturated compound) having at least one ethylenically unsaturated bond. As the ethylenically unsaturated compound, a compound having at least one terminal ethylenically unsaturated bond is preferred, and a compound having two or more terminal ethylenically unsaturated bonds is more preferred. The polymerizable compound can have, for example, a chemical form of a monomer, a prepolymer (dimer, trimer, or oligomer), or a mixture thereof.

[0508] As examples of the monomer, mention can be made of unsaturated carboxylic acids (e.g., acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid), esters thereof, amides thereof. Preferred are esters of unsaturated carboxylic acids and polyhydric alcohol compounds, amides of unsaturated carboxylic acids and polyhydric amine compounds. Also, preferred are addition reaction products of unsaturated carboxylic acid esters or amides having nucleophilic substituents such as hydroxyl groups, amino groups, mercapto groups, and the like, and monofunctional or polyfunctional isocyanates or epoxies, and dehydration condensation reaction products of monofunctional or polyfunctional carboxylic acids, and the like. Also, preferred are addition reaction products of unsaturated carboxylic acid esters or amides having electrophilic substituents such as isocyanate groups, epoxy groups, and the like, and monofunctional or polyfunctional alcohols, amines, thiols, and more preferred are substitution reaction products of unsaturated carboxylic acid esters or amides having leaving substituents such as halogen atoms, tosylate groups, and the like, and monofunctional or polyfunctional alcohols, amines, thiols. Also, as another example, it is possible to use a group of compounds in which the above unsaturated carboxylic acid is replaced by an unsaturated phosphonic acid, styrene, vinyl ether, and the like. These compounds are described in Japanese Patent Application Publication No. 2006-508380, Japanese Patent Application Publication No. 2002-287344, Japanese Patent Application Publication No. 2008-256850, Japanese Patent Application Publication No. 2001-342222, Japanese Patent Application Publication No. 1999-179296, Japanese Patent Application Publication No. 1999-179297, Japanese Patent Application Publication No. 1999-179298, Japanese Patent Application Publication No. 2004-294935, Japanese Patent Application Publication No. 2006-243493, Japanese Patent Application Publication No. 2002-275129, Japanese Patent Application Publication No. 2003-64130, Japanese Patent Application Publication No. 2003-280187, Japanese Patent Application Publication No. 2000-333321, and the like.

[0509] As specific examples of the ester monomer of a polyol compound and an unsaturated carboxylic acid, as an acrylate, ethylene glycol diacrylate, 1,3-butanediol diacrylate, tetramethylene glycol diacrylate, propylene glycol diacrylate, trimethylolpropane triacrylate, hexanediol diacrylate, tetraethylene glycol diacrylate, pentaerythritol tetraacrylate, sorbitol triacrylate, isocyanurate ethylene oxide (EO) modified triacrylate, polyester acrylate oligomer, and the like can be given. As a methacrylate, tetramethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, pentaerythritol trimethacrylate, bis[p-(3-methacryloyloxy-2-hydroxypropoxy)phenyl]dimethylmethane, bis[p-(methacryloyloxyethoxy)phenyl]dimethylmethane, and the like can be given. Also, as specific examples of the amide monomer of a polyamine compound and an unsaturated carboxylic acid, methylene bisacrylamide, methylene bismethacrylamide, 1,6-hexamethylene bisacrylamide, 1,6-hexamethylene bismethacrylamide, diethylenetriamine triacrylamide, xylylene bisacrylamide, diphenylene bismethacrylamide, and the like can be given.

[0510] Also, a urethane-based addition polymerizable compound produced by the addition reaction of an isocyanate and a hydroxyl group is also preferable, and as specific examples thereof, for example, a vinyl urethane compound having two or more polymerizable vinyl groups in one molecule obtained by the addition of a polyisocyanate compound having two or more isocyanate groups in one molecule to a hydroxyl group-containing vinyl monomer represented by the following formula (M) and the like described in Japanese Patent Application Publication No. 48-41708 can be given.

[0511] CH2=C(R M4 )COOCH2CH(R M5 )OH (M)

[0512] In formula (M), R M4 and R M5 each independently represent a hydrogen atom or a methyl group.

[0513] Also, urethane acrylates described in Japanese Patent Application Publication No. 51-37193, Japanese Patent No. 2-32293, Japanese Patent No. 2-16765, Japanese Patent Application Publication No. 2003-344997, Japanese Patent Application Publication No. 2006-65210, Japanese Patent No. 58-49860, Japanese Patent No. 56-17654, Japanese Patent No. 62-39417, Japanese Patent No. 62-39418, Japanese Patent Application Publication No. 2000-250211, Japanese Patent Application Publication No. 2007-94138, urethane compounds having an oxirane skeleton described in U.S. Patent No. 7153632, Japanese Patent Application Laid-Open No. 8-505958, Japanese Patent Application Publication No. 2007-293221, Japanese Patent Application Publication No. 2007-293223, and urethane compounds having a hydrophilic group are also preferable.

[0514] The structure of the polymerizable compound, the method of use of the polymerizable compound alone or in combination, the amount of the polymerizable compound to be added, and the like can be arbitrarily set in consideration of the end use of the lithographic printing plate precursor and the like.

[0515] The content of the polymerizable compound is preferably 1 to 50 mass%, more preferably 3 to 30 mass%, and further preferably 5 to 20 mass% in the total solid content of the image-recording layer.

[0516] (Polymer compound)

[0517] The polymer compound can function as a binder polymer of the image-recording layer, or can exist in the image-recording layer as a polymer compound in the form of particles (polymer particles).

[0518] (Binder polymer)

[0519] As the binder polymer, a polymer having a film-forming property is preferable, and a (meth)acrylic resin, a polyvinyl acetal resin, a polyurethane resin, and the like are preferably selected.

[0520] As the binder polymer used in the image-recording layer, a binder polymer having an alkylene oxide chain is preferable. The binder polymer having an alkylene oxide chain can have a poly(alkylene oxide) site in the main chain or in the side chain. Also, it can be a graft polymer having a poly(alkylene oxide) site in the side chain, or a block copolymer of a block composed of a repeating unit containing a poly(alkylene oxide) site and a block composed of a repeating unit not containing an (alkylene oxide) site.

[0521] In the case where the main chain has a poly(alkylene oxide) moiety, a polyurethane resin is preferred. As the polymer of the main chain in the case where the side chain has a poly(alkylene oxide) moiety, a (meth)acrylic resin, a polyvinyl acetal resin, a polyurethane resin, a polyurea resin, a polyimide resin, a polyamide resin, an epoxy resin, a polystyrene resin, a novolak phenol resin, a polyester resin, a synthetic rubber, a natural rubber, and the like can be given, with a (meth)acrylic resin being particularly preferred.

[0522] As the alkylene oxide, an alkylene oxide having 2 to 6 carbon atoms is preferred, with an ethylene oxide or a propylene oxide being particularly preferred.

[0523] The number of repetitions of the alkylene oxide in the poly(alkylene oxide) moiety is preferably 2 to 120, more preferably 2 to 70, and further preferably 2 to 50.

[0524] If the number of repetitions of the alkylene oxide is 120 or less, the decrease in print durability due to abrasion and the decrease in print durability due to deterioration in ink receptivity can be suppressed, and thus is preferred.

[0525] With regard to the poly(alkylene oxide) moiety, as the side chain of the binder polymer, a structure represented by the following formula (AO) is preferred, and as the side chain of the (meth)acrylic resin, a structure represented by the following formula (AO) is more preferred.

[0526] [Chemical Formula 17]

[0527]

[0528] In formula (AO), y represents 2 to 120, R1represents a hydrogen atom or an alkyl group, and R2represents a hydrogen atom or a monovalent organic group.

[0529] As the monovalent organic group, an alkyl group having 1 to 6 carbon atoms is preferred. Specifically, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, an iso-butyl group, a t-butyl group, an n-pentyl group, an iso-pentyl group, a neopentyl group, an n-hexyl group, an iso-hexyl group, a 1,1-dimethylbutyl group, a 2,2-dimethylbutyl group, a cyclopentyl group, and a cyclohexyl group can be given.

[0530] In formula (AO), y is preferably 2 to 70, and more preferably 2 to 50. R1is preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom. R2is particularly preferably a hydrogen atom or a methyl group.

[0531] In order to improve the film strength of the image portion, the binder polymer can have cross-linkability. In order to impart cross-linkability to the polymer, a cross-linkable functional group such as an olefinic unsaturated bond can be introduced into the main chain or the side chain of the polymer. The cross-linkable functional group can be introduced by copolymerization or by polymer reaction.

[0532] As examples of the polymer having an ethylenic unsaturated bond in the main chain of the molecule, poly-1,4-butadiene, poly-1,4-isoprene, etc. can be given.

[0533] As examples of the polymer having an ethylenic unsaturated bond in the side chain of the molecule, the polymer which is a polymer of an ester or an amide of acrylic acid or methacrylic acid and the residue (R of -COOR or -CONHR) of the ester or the amide has an ethylenic unsaturated bond can be given.

[0534] As examples of the residue (R) having an ethylenic unsaturated bond, -(CH2) n CR 1A =CR 2A R 3A , -(CH2O) n CH2CR 1A =CR 2A R 3A , -(CH2CH2O) n CH2CR 1A =CR 2A R 3A , -(CH2) n NH-CO-O-CH2CR 1A =CR 2A R 3A , -(CH2) n- O-CO-CR 1A =CR 2A R 3A and -(CH2CH2O)2-X A (In the formula, R A1 ~ R A3 each independently represent a hydrogen atom, a halogen atom, an alkyl group having a carbon atom number of 1 to 20, an aryl group, an alkoxy group or an aryloxy group, R A1 and R A2 or R A3 may be bonded to each other to form a ring. n represents an integer of 1 to 10. X A represents a dicyclopentadiene residue.).

[0535] As specific examples of the residue of the ester, -CH2CH=CH2, -CH2CH2O-CH2CH=CH2, -CH2C(CH3)=CH2, -CH2CH=CH-C6H5, -CH2CH2OCOCH=CH-C6H5, -CH2CH2-NHCOO-CH2CH=CH2and -CH2CH2O-X (in the formula, X represents a dicyclopentadiene residue.) can be given.

[0536] Specific examples of the residue of an amide include -CH2CH=CH2, -CH2CH2-Y (where Y represents a cyclohexene residue), and -CH2CH2-OCO-CH=CH2.

[0537] The adhesive polymer having cross-linkability, for example, a radical that adds to the cross-linking functional group (a polymerization initiation radical or a growing radical of the polymerization process of the polymerizable compound), adds polymerization between the polymer molecules directly or via the polymerization chain of the polymerizable compound, thereby forming cross-linking between the polymer molecules and curing. Alternatively, an atom in the polymer (for example, a hydrogen atom on a carbon atom adjacent to the functional cross-linking group) is abstracted by a radical and generates a polymer radical, and the polymer radicals bond to each other, thereby forming cross-linking between the polymer molecules and curing.

[0538] From the viewpoint of good sensitivity and good storage stability, the content of the cross-linking group in the adhesive polymer (the content of the unsaturated double bond capable of radical polymerization by iodine titration) is preferably 0.1 to 10.0 mmol, more preferably 1.0 to 7.0 mmol, and further preferably 2.0 to 5.5 mmol per 1 g of the adhesive polymer.

[0539] Hereinafter, specific examples 1 to 11 of the adhesive polymer are shown, but the present application is not limited to these. In the following example compounds, the values of the repeating units (the values of the repeating units of the main chain) collectively described in each repeating unit indicate the molar percentage of the repeating units. The values of the repeating units of the side chain collectively described in the side chain indicate the number of repetitions of the repeating sites. Furthermore, Me represents a methyl group, Et represents an ethyl group, and Ph represents a phenyl group.

[0540] [Chemical Formula 18]

[0541]

[0542] [Chemical Formula 19]

[0543]

[0544] Regarding the molecular weight of the adhesive polymer, the weight average molecular weight (Mw) is 2,000 or more, preferably 5,000 or more, and more preferably 10,000 to 300,000, as a polystyrene conversion value based on the GPC method.

[0545] If necessary, a hydrophilic polymer such as a polyacrylic acid, a polyvinyl alcohol, and the like described in Japanese Patent Application Publication No. 2008-195018 can be used in combination. Furthermore, a lipophilic polymer and a hydrophilic polymer can also be used in combination.

[0546] The adhesive polymer can be used alone or in combination with two or more kinds.

[0547] The content of the binder polymer is preferably 1 to 90 mass%, more preferably 5 to 80 mass%, in the total solid content of the image recording layer.

[0548] <Polymer particles>

[0549] The image recording layer preferably contains polymer particles. The polymer particles contribute to improvement of on-press developability. The polymer particles are preferably polymer particles that can convert the image recording layer into a hydrophobic state upon application of heat. The polymer particles are preferably at least one selected from the group consisting of hydrophobic thermoplastic polymer particles, thermally reactive polymer particles, polymer particles having a polymerizable group, microcapsules containing a hydrophobic compound, and microgels (crosslinked polymer particles).

[0550] As the hydrophobic thermoplastic polymer particles, hydrophobic thermoplastic polymer particles described in Research Disclosure No. 33303, January 1992, Japanese Patent Application Laid-Open No. 9-123387, Japanese Patent Application Laid-Open No. 9-131850, Japanese Patent Application Laid-Open No. 9-171249, Japanese Patent Application Laid-Open No. 9-171250, and European Patent No. 931647, and the like are preferably selected.

[0551] As specific examples of the polymer constituting the hydrophobic thermoplastic polymer particles, mention can be made of homopolymers or copolymers of monomers such as ethylene, styrene, vinyl chloride, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, vinylidene chloride, acrylonitrile, vinylcarbazole, acrylate or methacrylate having a polyalkylene structure, or mixtures thereof. Copolymers containing polystyrene, styrene and acrylonitrile, and polymethyl methacrylate are preferably selected. The average particle diameter of the hydrophobic thermoplastic polymer particles is preferably 0.01 to 2.0 μm.

[0552] As the thermally reactive polymer particles, mention can be made of polymer particles having a thermally reactive group. The polymer particles having a thermally reactive group form a hydrophobic region by crosslinking based on thermal reaction and a change in functional group upon crosslinking.

[0553] As the thermally reactive group in the polymer particles having a thermally reactive group, if a chemical bond is formed, it can be a functional group that undergoes any reaction, and a polymerizable group is preferable. As examples thereof, an ethylenically unsaturated group (e.g., acryloyl group, methacryloyl group, vinyl group, allyl group, etc.) that undergoes a radical polymerization reaction, a cationically polymerizable group (e.g., vinyl group, vinyloxy group, epoxy group, oxetanyl group, etc.), an isocyanate group or a block thereof that undergoes an addition reaction, an epoxy group, a vinyloxy group, and a functional group having an active hydrogen atom (e.g., amino group, hydroxyl group, carboxyl group, etc.) that is a reaction partner of these, a carboxyl group and a hydroxyl group or an amino group that are reaction partners, an acid anhydride and an amino group or a hydroxyl group that are reaction partners that undergo a condensation reaction, and the like can be preferably selected.

[0554] As the microcapsule, for example, a microcapsule in which all the components or a part of the components of the image recording layer are contained in the microcapsule, as described in Japanese Patent Application Publication No. 2001-277740 and Japanese Patent Application Publication No. 2001-277742, can be mentioned. The components of the image recording layer can also be contained outside the microcapsule. As the image recording layer containing the microcapsule, a preferable mode is to contain the hydrophobic components in the microcapsule, and to contain the hydrophilic components outside the microcapsule.

[0555] The microgel (crosslinked polymer particles) can contain a part of the components of the image recording layer in at least one of the inside and the surface thereof. In particular, from the viewpoint of image formation sensitivity or print durability, a mode in which a reactive microgel is made by having a radical polymerizable group on the surface thereof is preferable.

[0556] In order to microcapsulate or microgelate the components of the present image recording layer, a publicly known method can be used.

[0557] The average particle diameter of the microcapsule or the microgel is preferably 0.01 to 3.0 μm, more preferably 0.05 to 2.0 μm, and particularly preferably 0.10 to 1.0 μm. In this range, good resolution and stability over time can be obtained.

[0558] The polymer particles can be used singly with one kind, or two or more kinds can be used in combination.

[0559] The content of the polymer particles is preferably 5 to 90% by mass, more preferably 5 to 80% by mass, and further preferably 10 to 75% by mass, in the total solid components of the image recording layer.

[0560] As the high molecular compound contained in the image recording layer, a high molecular compound containing at least one of a structural unit derived from a styrene compound and a structural unit derived from an acrylonitrile compound is also preferable. From the viewpoint of contributing to on-press developability, this high molecular compound can be preferably used as a binder polymer or a polymer particle.

[0561] As the styrene compound, styrene, p-methylstyrene, p-methoxystyrene, β-methylstyrene, p-methyl-β-methylstyrene, α-methylstyrene, p-methoxy-β-methylstyrene, and the like can be given, with styrene being preferred.

[0562] As the acrylonitrile compound, acrylonitrile, methacrylonitrile, and the like can be given, with acrylonitrile being preferred.

[0563] In the high molecular compound containing the styrene compound and the acrylonitrile compound as the structural unit, the composition ratio of the structural unit derived from the styrene compound to the structural unit derived from the acrylonitrile compound is preferably 4: 1 to 1:4.

[0564] Further, the high molecular compound preferably contains at least a polyvinyl butyl resin.

[0565] The image recording layer can contain an infrared absorber.

[0566] (Infrared absorber)

[0567] The above-mentioned infrared absorber is the above-mentioned specific infrared absorber or an infrared absorber other than the above-mentioned specific infrared absorber (also referred to as "other infrared absorber").

[0568] In the case where the at least one layer containing the specific infrared absorber is the image forming layer, the above-mentioned infrared absorber is the above-mentioned specific infrared absorber. The image forming layer can have the other infrared absorber within a range not impairing the effects of the present application.

[0569] <Other infrared absorber>

[0570] The other infrared absorber is an infrared absorber other than the above-mentioned specific infrared absorber, and is a compound having a HOMO exceeding -5.43 eV.

[0571] As the dye, a commercially available dye and a well-known dye described in documents such as "Dye Handbook" (The Society of Synthetic Organic Chemistry, Japan. Editor, published in 1965) can be used. Specifically, azo dyes, metal complex azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinonimine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrilium salts, metal thiol complexes, and the like can be given.

[0572] Among the dyes, cyanine pigments, squarylium pigments, pyrilium salts are preferred, with cyanine pigments being more preferred, and indocyanine pigments being particularly preferred.

[0573] As specific examples of the cyanine dye, the compounds described in paragraphs 0017 to 0019 of Japanese Patent Application Publication No. 2001-133969, paragraphs 0016 to 0021 of Japanese Patent Application Publication No. 2002-023360, and paragraphs 0012 to 0037 of Japanese Patent Application Publication No. 2002-040638 can be given, and the compounds described in paragraphs 0034 to 0041 of Japanese Patent Application Publication No. 2002-278057, paragraphs 0080 to 0086 of Japanese Patent Application Publication No. 2008-195018 are preferably given, and the compounds described in paragraphs 0035 to 0043 of Japanese Patent Application Publication No. 2007-90850 are particularly preferably given.

[0574] Further, the compounds described in paragraphs 0008 to 0009 of Japanese Patent Application Publication No. 5-5005, and paragraphs 0022 to 0025 of Japanese Patent Application Publication No. 2001-222101 can also be preferably used.

[0575] As the pigment, the compounds described in paragraphs 0072 to 0076 of Japanese Patent Application Publication No. 2008-195018 are preferably given.

[0576] In the case where the image forming layer does not contain the specific infrared absorber, but contains other infrared absorbers, one kind of other infrared absorber can be used alone, or two or more kinds of other infrared absorbers can be used in combination.

[0577] The content of the other infrared absorber is preferably 0.05 to 30% by mass, more preferably 0.1 to 20% by mass, and further preferably 0.2 to 10% by mass, in the total solid content of the image recording layer.

[0578] In the case where the image forming layer contains the specific infrared absorber, other infrared absorbers can be present or can not be present, but it is preferable that other infrared absorbers are not present.

[0579] The image recording layer can contain a chain transfer agent, a low-molecular hydrophilic compound, a sensitizing agent, and other components.

[0580] (Chain transfer agent)

[0581] The chain transfer agent is effective in improving the print durability in the lithographic printing plate produced from the lithographic printing plate precursor.

[0582] As the chain transfer agent, a mercaptan compound is preferable, and from the viewpoint of the boiling point (difficulty of volatilization), a mercaptan having 7 or more carbon atoms is more preferable, and a compound having a mercapto group on an aromatic ring (aromatic mercaptan compound) is further preferable. The mercaptan compound is preferably a monofunctional mercaptan compound.

[0583] As specific examples of the chain transfer agent, the following compounds can be given.

[0584] [Chemical Formula 20]

[0585]

[0586] [Chemical Formula 21]

[0587]

[0588] [Chemical Formula 22]

[0589]

[0590] [Chemical Formula 23]

[0591]

[0592] The chain transfer agent can be used singly or in combination of two or more.

[0593] The content of the chain transfer agent is preferably 0.01 to 50% by mass, more preferably 0.05 to 40% by mass, and further preferably 0.1 to 30% by mass, in the total solid content of the image recording layer.

[0594] Low-molecular hydrophilic compound

[0595] The low-molecular hydrophilic compound does not decrease the print durability of the lithographic printing plate produced from the lithographic printing plate precursor, and is useful in improving the on-press developability of the lithographic printing plate precursor. The low-molecular hydrophilic compound is preferably a compound having a molecular weight of less than 1,000, more preferably a compound having a molecular weight of less than 800, and further preferably a compound having a molecular weight of less than 500.

[0596] As the low-molecular hydrophilic compound, for example, as the water-soluble organic compound, there can be mentioned glycols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, and the like, and ether or ester derivatives thereof, glycerol, pentaerythritol, tri(2-hydroxyethyl) isocyanurate, and the like, polyhydric alcohols, organic amine compounds such as triethanolamine, diethanolamine, monoethanolamine, and the like, and salts thereof, organic sulfonic acids such as alkylsulfonic acid, p-toluenesulfonic acid, benzene sulfonic acid, and the like, and salts thereof, organic aminosulfonic acids such as alkylaminosulfonic acid, and salts thereof, organic sulfuric acids such as alkylsulfuric acid, alkyl ether sulfuric acid, and the like, and salts thereof, organic phosphonic acids such as phenylphosphonic acid, and salts thereof, organic carboxylic acids such as tartaric acid, oxalic acid, citric acid, malic acid, lactic acid, gluconic acid, amino acids, and the like, and salts thereof, betaines, and the like.

[0597] The low-molecular hydrophilic compound is preferably at least one selected from the group consisting of polyhydric alcohols, organic sulfuric acid salts, organic sulfonic acid salts, and betaines.

[0598] As specific examples of the organic sulfonic acid salts, there are mentioned sodium n-butylsulfonate, sodium n-hexylsulfonate, sodium 2-ethylhexylsulfonate, sodium cyclohexylsulfonate, sodium n-octylsulfonate and the like alkylsulfonates; sodium 5,8,11-trioxa-pentadecane-1-sulfonate, sodium 5,8,11-trioxa-heptadecane-1-sulfonate, sodium 13-ethyl-5,8,11-trioxa-heptadecane-1-sulfonate, sodium 5,8,11,14-tetraoxa-tetracosane-1-sulfonate and the like alkylsulfonates containing an ethylene oxide chain; sodium benzenesulfonate, sodium p-toluenesulfonate, sodium p-hydroxybenzenesulfonate, sodium p-styrenesulfonate, sodium dimethyl isophthalate-5-sulfonate, sodium 1-naphthylsulfonate, sodium 4-hydroxynaphthalene sulfonate, disodium 1,5-naphthalene disulfonate, trisodium 1,3,6-naphthalene trisulfonate and the like arylsulfonates, the compounds described in paragraphs 0026 to 0031 of Japanese Patent Application Publication No. 2007-276454 and paragraphs 0020 to 0047 of Japanese Patent Application Publication No. 2009-154525, and the like. The salt can be a potassium salt, a lithium salt or the like.

[0599] As the organic sulfate salts, there are mentioned alkyl, alkenyl, alkynyl, aryl or heterocyclic monoether sulfates of polyethylene oxide. The number of ethylene oxide units is preferably 1 to 4, and the salt is preferably a sodium salt, a potassium salt or a lithium salt. As specific examples, there are mentioned the compounds described in paragraphs 0034 to 0038 of Japanese Patent Application Publication No. 2007-276454, and the like.

[0600] As the betaines, there are preferably compounds in which the number of carbon atoms of the hydrocarbon substituent for the nitrogen atom is 1 to 5, and as specific examples, there are mentioned trimethylammonium acetate, dimethylpropylammonium acetate, 3-hydroxy-4-trimethylammonium butyrate, 4-(1-pyridyl)butyrate, 1-hydroxyethyl-1-imidazole acetate, trimethylammonium methane sulfonate, dimethylpropylammonium methane sulfonate, 3-trimethylammonium-1-propane sulfonate, 3-(1-pyridyl)-1-propane sulfonate and the like.

[0601] The low-molecular hydrophilic compound does not penetrate the exposed portion (image portion) of the image recording layer because the structure of the hydrophobic portion thereof is small and the compound has little surface activity, and thus the hydrophobicity or the film strength of the image portion is not reduced, so that the ink receptivity and the print durability of the image recording layer can be maintained favorably.

[0602] The low-molecular hydrophilic compound can be used singly or in combination of two or more.

[0603] The content of the low-molecular hydrophilic compound is preferably 0.5 to 20% by mass, more preferably 1 to 15% by mass, and further preferably 2 to 10% by mass, in the total solid content of the image recording layer.

[0604] (Sensitizer)

[0605] The sensitizer is effective in improving ink receptivity (hereinafter, also simply referred to as "receptivity") in a lithographic printing plate produced from a lithographic printing plate precursor. As the sensitizer, phosphonium compounds, nitrogen-containing low-molecular compounds, and ammonium group-containing polymers can be given. In particular, in the case where the lithographic printing plate precursor has a protective layer containing an inorganic layered compound, these compounds function as a surface covering agent for the inorganic layered compound, and have a function of suppressing a decrease in receptivity during printing due to the inorganic layered compound.

[0606] As the sensitizer, a combination of a phosphonium compound, a nitrogen-containing low-molecular compound, and an ammonium group-containing polymer is preferred, and a combination of a phosphonium compound, a quaternary ammonium salt, and an ammonium group-containing polymer is more preferred.

[0607] As the phosphonium compound, phosphonium compounds described in Japanese Patent Application Laid-Open No. 2006-297907 and Japanese Patent Application Laid-Open No. 2007-50660 can be given. As specific examples, tetrabutylphosphonium iodide, butyltriphenylphosphonium bromide, tetraphenylphosphonium bromide, 1,4-bis(triphenylphosphine)butane di(hexafluorophosphate), 1,7-bis(triphenylphosphine)heptane sulfate, 1,9-bis(triphenylphosphine)nonane naphthalene-2,7-disulfonate, and the like can be given.

[0608] As the nitrogen-containing low-molecular compound, amine salts, quaternary ammonium salts can be given. Also, imidazolinium salts, benzimidazolinium salts, pyridinium salts, quinolinium salts can be given. Among them, quaternary ammonium salts and pyridinium salts are preferred. As specific examples, tetramethylammonium hexafluorophosphate, tetrabutylammonium hexafluorophosphate, dodecyltrimethylammonium p-toluenesulfonate, benzyltriethylammonium hexafluorophosphate, benzyl dimethyl octyl ammonium hexafluorophosphate, benzyl dimethyl dodecyl ammonium hexafluorophosphate, compounds described in paragraphs 0021 to 0037 of Japanese Patent Application Laid-Open No. 2008-284858, paragraphs 0030 to 0057 of Japanese Patent Application Laid-Open No. 2009-90645, and the like can be given.

[0609] As the ammonium group-containing polymer, a polymer having an ammonium group in the structure thereof is sufficient, and a polymer having 5 to 80 mol% of a (meth)acrylate having an ammonium group in the side chain as a copolymerization component is preferred. As a specific example, a polymer described in paragraphs 0089 to 0105 of Japanese Patent Application Laid-Open No. 2009-208458 can be given.

[0610] The value of the specific viscosity (unit: ml / g) of the ammonium group-containing polymer, which is measured by the method described in Japanese Patent Application Laid-Open No. 2009-208458, is preferably in the range of 5 to 120, more preferably in the range of 10 to 110, and particularly preferably in the range of 15 to 100. When the specific viscosity described above is converted into the weight average molecular weight (Mw), it is preferably in the range of 10,000 to 150,000, more preferably in the range of 17,000 to 140,000, and particularly preferably in the range of 20,000 to 130,000.

[0611] Hereinafter, specific examples of the ammonium group-containing polymer will be shown.

[0612] (1) 2-(trimethylammonium)ethyl methacrylate = p-toluenesulfonate / 3,6-dioxymethylpropyl methacrylate copolymer (molar ratio 10 / 90, Mw 45,000)

[0613] (2) 2-(trimethylammonium)ethyl methacrylate = hexafluorophosphate / 3,6-dioxymethylpropyl methacrylate copolymer (molar ratio 20 / 80, Mw 60,000)

[0614] (3) 2-(ethyldimethylammonium)ethyl methacrylate = p-toluenesulfonate / hexyl methacrylate copolymer (molar ratio 30 / 70, Mw 45,000)

[0615] (4) 2-(trimethylammonium)ethyl methacrylate = hexafluorophosphate / 2-ethylhexyl methacrylate copolymer (molar ratio 20 / 80, Mw 60,000)

[0616] (5) 2-(trimethylammonium)ethyl methacrylate = methyl sulfate / hexyl methacrylate copolymer (molar ratio 40 / 60, Mw 70,000)

[0617] (6) 2-(butyldimethylammonium)ethyl methacrylate = hexafluorophosphate / 3,6-dioxymethylpropyl methacrylate copolymer (molar ratio 25 / 75, Mw 65,000)

[0618] (7) 2-(butyldimethylammonium)ethyl methacrylate = hexafluorophosphate / 3,6-dioxymethylpropyl methacrylate copolymer (molar ratio 20 / 80, Mw 65,000)

[0619] (8) 2-(butyldimethylammonium)ethyl methacrylate = 13-ethyl-5,8,11-trioxa-1-heptadecanesulfonate / 3,6-dioxymethylpropyl methacrylate copolymer (molar ratio 20 / 80, Mw 75,000)

[0620] (9) 2-(butyldimethylammonium)ethyl methacrylate = hexafluorophosphate / 3,6-dioxahexyl methacrylate / 2-hydroxy-3-methacryloyloxypropyl methacrylate copolymer (molar ratio 15 / 80 / 5, Mw 65,000)

[0621] The content of the sensitizing agent is preferably 0.01 to 30 mass%, more preferably 0.1 to 15 mass%, and further preferably 1 to 10 mass%, in the total solid content of the image recording layer.

[0622] (Other components)

[0623] The image recording layer can contain a surfactant, a printing agent, a polymerization inhibitor, a higher fatty acid derivative, a plasticizer, an inorganic particle, an inorganic layered compound, an acid color developer, a hydrophilic compound, and the like as other components. Specifically, each of the above components described in paragraphs 0114 to 0159 of Japanese Patent Application Publication No. 2008-284817 can be used.

[0624] The image recording layer can contain a specific infrared absorbing agent. At this time, the image recording layer corresponds to a specific structure layer.

[0625] (Formation of image recording layer)

[0626] The image recording layer can be formed, for example, by preparing a coating solution in which necessary each of the above components is appropriately dispersed or dissolved in a well-known solvent, as described in paragraphs 0142 to 0143 of Japanese Patent Application Publication No. 2008-195018, coating the coating solution by a well-known method such as a bar coater, and drying. The coating amount (solid content) of the image recording layer after coating and drying varies depending on the use, but from the viewpoint of obtaining good sensitivity and good film properties of the image recording layer, it is preferably 0.3 to 3.0 g / m2, and more preferably 0.5 to 2.0 g / m2. 2 left and right.

[0627] The lithographic printing plate precursor can have a primer layer (sometimes referred to as an intermediate layer) between the image recording layer and the support, and can have a protective layer (sometimes referred to as an outer coating layer) on the image recording layer.

[0628] [Primer layer]

[0629] The primer layer enhances the adhesion of the support to the image recording layer in the exposed portion, and makes the image recording layer easy to be peeled from the support in the unexposed portion, and thus contributes to the improvement of the developability without impairing the print durability. Also, in the case of infrared laser exposure, the primer layer functions as a heat insulating layer, and thus also has the effect of preventing the heat generated by exposure from diffusing to the support, resulting in the reduction of sensitivity.

[0630] As the compound used for the undercoat layer, a polymer having an adsorptive group and a hydrophilic group that can be adsorbed to the surface of the support can be mentioned. In order to improve the adhesion to the image-recording layer, a polymer having an adsorptive group and a hydrophilic group, and further having a cross-linkable group is preferable. The compound used in the undercoat layer can be either a low-molecular compound or a polymer. The compound used for the undercoat layer can be used by mixing two or more kinds as needed.

[0631] In the case where the compound used for the undercoat layer is a polymer, a copolymer of a monomer having an adsorptive group, a monomer having a hydrophilic group, and a monomer having a cross-linkable group is preferable.

[0632] As the adsorptive group that can be adsorbed to the surface of the support, a phenolic hydroxyl group, a carboxyl group, -PO3H2, -OPO3H2, -CONHSO2-, -SO2NHSO2-, -COCH2COCH3 are preferable. As the hydrophilic group, a sulfo group or a salt thereof, a salt of a carboxyl group are preferable. As the cross-linkable group, an acryloyl group, a methacryloyl group, an acrylamide group, a methacrylamide group, an allyl group, and the like are preferable.

[0633] The polymer can have a cross-linkable group introduced by the salt of a compound having a substituent having a charge opposite to that of the polar substituent of the polymer and an olefinic unsaturated bond, and can further be copolymerized with a monomer other than the above, preferably a hydrophilic monomer.

[0634] Specifically, a silane coupling agent having an olefinic double bond reactive group capable of addition polymerization described in Japanese Patent Application Laid-Open No. 10-282679, a phosphorus compound having an olefinic double bond reactive group described in Japanese Patent Application Laid-Open No. 2-304441 are preferable. It is also preferable to use a low-molecular or high-molecular compound having a cross-linkable group (preferably an olefinic unsaturated bond group), a functional group that interacts with the surface of the support, and a hydrophilic group described in Japanese Patent Application Laid-Open No. 2005-238816, Japanese Patent Application Laid-Open No. 2005-125749, Japanese Patent Application Laid-Open No. 2006-239867, and Japanese Patent Application Laid-Open No. 2006-215263.

[0635] As a more preferable compound, a high-molecular polymer having an adsorptive group that can be adsorbed to the surface of the support, a hydrophilic group, and a cross-linkable group described in Japanese Patent Application Laid-Open No. 2005-125749 and Japanese Patent Application Laid-Open No. 2006-188038 can be mentioned.

[0636] The content of the olefinic unsaturated bond group in the polymer used in the undercoat layer is preferably 0.1 to 10.0 mmol, more preferably 0.2 to 5.5 mmol, per 1 g of the polymer.

[0637] The weight average molecular weight (Mw) of the polymer used in the primer layer is preferably 5,000 or more, more preferably 10,000 to 300,000.

[0638] In the primer layer, in addition to the above-mentioned primer layer compound, in order to prevent the passage of time from causing contamination, a chelating agent, a secondary or tertiary amine, a polymerization inhibitor, a compound having an amino group or a functional group having a polymerization inhibiting effect, and a compound having a group that interacts with the surface of the support (for example, 1,4-diazabicyclo[2.2.2]octane (DABCO), 2,3,5,6-tetrahydroxy-p-benzoquinone, chloranil, sulfophthalic acid, hydroxyethyl ethylenediaminetriacetic acid, dihydroxyethyl ethylenediamine diacetic acid, hydroxyethyl imino diacetic acid, and the like) and the like can also be contained.

[0639] The primer layer can contain a specific infrared absorbing agent. In this case, the primer layer corresponds to the specific structure layer.

[0640] The primer layer can be formed by applying and drying using a publicly known method. The application amount (solid content) of the primer layer after drying is preferably 0.1 to 100 mg / m 2 , more preferably 1 to 30 mg / m 2 .

[0641] [Protective Layer]

[0642] The protective layer has a function of preventing scratches in the image recording layer and a function of preventing ablation at the time of high-intensity laser exposure in addition to a function of inhibiting image formation hindering reactions by blocking oxygen.

[0643] The protective layer having such a property is described, for example, in U.S. Patent No. 3,458,311 and Japanese Patent Application Publication No. S55-49729. As the low oxygen permeability polymer used in the protective layer, either one of a water-soluble polymer and a water-insoluble polymer can be appropriately selected and used, and two or more kinds can also be used in combination as needed. Specifically, for example, polyvinyl alcohol resins (including polyvinyl alcohol and modified polyvinyl alcohol), polyvinylpyrrolidone, water-soluble cellulose derivatives, poly(meth)acrylonitrile, and the like can be mentioned.

[0644] As the polyvinyl alcohol, a polyvinyl alcohol having a saponification degree of 50% or more is preferred. The saponification degree of the polyvinyl alcohol is preferably 60% or more, more preferably 70% or more, and further preferably 85% or more. The upper limit of the saponification degree is not particularly limited, and the saponification degree can be 100% or less.

[0645] The saponification degree can be measured according to the method described in JIS K 6726:1994.

[0646] As the modified polyvinyl alcohol, an acid-modified polyvinyl alcohol having a carboxyl group or a sulfonic group can be preferably used. Specifically, the modified polyvinyl alcohol described in Japanese Patent Application Publication No. 2005-250216 and Japanese Patent Application Publication No. 2006-259137 can be mentioned.

[0647] Among the water-soluble polymers, a polyvinyl alcohol resin is preferred.

[0648] In order to improve the oxygen barrier property, it is preferred that the protective layer contains an inorganic layered compound. The inorganic layered compound is a particle having a thin plate shape, and for example, mica group, talc represented by the formula: 3MgO-4SiO-H2O, strip mica, montmorillonite, saponite, hectorite, zirconium phosphate, and the like can be mentioned.

[0649] The inorganic layered compound to be used is preferably a mica compound. As the mica compound, for example, mica group represented by the formula: A(B,C) 2-5 D4O 10 (OH, F, O)2(wherein A is any one of K, Na, and Ca, B and C are any one of Fe(II), Fe(III), Mn, Al, Mg, and V, and D is Si or Al), synthetic mica, and the like can be mentioned.

[0650] Among the mica group, as the natural mica, white mica, sodium mica, gold mica, black mica, and scaly mica can be mentioned. As the synthetic mica, non-swelling mica such as fluorine gold mica KMg3(AlSi3O 10 )F2, potassium tetrasilicic mica KMg 2.5 (Si4O 10 )F2, and the like, and Na tetrafluorosilicic mica NaMg 2.5 (Si4O 10 )F2, Na or Li strip mica (Na, Li)Mg2Li(Si4O 10 )F2, montmorillonite-based Na or Li hectorite (Na, Li) 1 / 8 Mg 2 / 5 Li 1 / 8 (Si4O 10 )F2, and the like swelling mica, and the like can be mentioned. Also, synthetic smectite is useful.

[0651] Among the mica compounds, fluorine-based swelling mica is particularly useful. That is, the swelling synthetic mica has a laminated structure including a unit cell layer having a thickness of about or less, and the metal atom substitution in the crystal lattice is remarkable compared to other clay minerals. As a result, the crystal lattice layer is positively charged deficient, and in order to compensate for this, Li + , Na + , Ca 2+ , Mg 2+Isomorphous ions. These interlayer oxygen ions are called exchangeable oxygen ions, and can be exchanged with various oxygen ions. In particular, when the interlayer oxygen ions are Li + , Na + , the ionic radius is small, and thus the bonding between the layered lattices is weak, and is greatly swollen by water. If a shear force is applied in this state, it is easily broken, and a stable sol is formed in water. This tendency of the swellable synthetic mica is strong, and is particularly preferably used.

[0652] As the shape of the mica compound, from the viewpoint of controlling diffusion, the thinner the thickness, the better, and the larger the planar size, the better, as long as the smoothness of the coated surface or the transmission of the activated light is not inhibited. Therefore, the aspect ratio is preferably 20 or more, more preferably 100 or more, and particularly preferably 200 or more. The aspect ratio is the ratio of the length diameter to the thickness of the particle, and can be measured, for example, from a projection drawing based on a microscope photograph of the particle. The larger the aspect ratio, the greater the effect obtained.

[0653] As for the particle diameter of the mica compound, the average length diameter is preferably 0.3 to 20 μm, more preferably 0.5 to 10 μm, and particularly preferably 1 to 5 μm. The average thickness of the particle is preferably 0.1 μm or less, more preferably 0.05 μm or less, and particularly preferably 0.01 μm or less. Specifically, for example, when it is the swellable synthetic mica, which is a representative compound, as a preferable mode, the thickness is 1 to 50 nm, and the planar size (length diameter) is about 1 to 20 μm.

[0654] The content of the inorganic layered compound is preferably 0 to 60 mass%, and more preferably 3 to 50 mass%, relative to the total solid content of the protective layer. Even in the case where a plurality of inorganic layered compounds are used in combination, the total amount of the inorganic layered compounds is preferably the above content. Within the above range, the oxygen barrier property is improved, and a good sensitivity can be obtained. Also, it is possible to prevent a decrease in ink receptivity.

[0655] The protective layer can contain a known additive such as a plasticizer for imparting flexibility, a surfactant for improving coatability, inorganic fine particles for controlling surface slip property, and the like. Also, the sensitizing agent described in the image recording layer can be contained in the protective layer.

[0656] The protective layer can contain a specific infrared absorbing agent. At this time, the protective layer corresponds to the specific structure layer.

[0657] The protective layer can be formed by coating and drying using a known method. The coating amount (solid content) of the protective layer after drying is preferably 0.01 to 10 g / m 2 , more preferably 0.02 to 3 g / m 2 , and particularly preferably 0.02 to 1 g / m 2 .

[0658] The lithographic printing plate precursor according to the present application preferably has a bevel shape at the end portion.

[0659] Figure 3 is a schematic view showing a cross-sectional shape of an end portion of a lithographic printing plate precursor as one mode.

[0660] In Figure 3 In the lithographic printing plate precursor 1, a bevel 2 is present at the end portion. The distance X from the upper end of the end surface 1c (the boundary point of the bevel 2 and the end surface 1c) to the intersection of the extension line of the end surface 1c and the extension line of the image recording layer face (the protective layer face in the case where a protective layer is formed) 1a is referred to as the "bevel amount X", and the distance Y from the point where the bevel starts from the image recording layer face 1a of the lithographic printing plate precursor 1 to the above-mentioned intersection is referred to as the "bevel width Y".

[0661] In the bevel shape of the end portion, the bevel amount X is preferably 25 μm or more, more preferably 35 μm or more, and further preferably 40 μm or more. From the viewpoint of preventing deterioration of on-press developability due to deterioration of the surface state of the end portion, the upper limit of the bevel amount X is preferably 150 μm. If the on-press developability deteriorates, ink sometimes adheres to the remaining image recording layer to become a cause of edge contamination. If the bevel amount X is too small, ink adhering to the end portion sometimes easily transfers to the blanket to become a cause of edge contamination. In the case where the bevel amount X is in the range of 25 to 150 μm, if the bevel width Y is small, the occurrence of cracks at the end portion sometimes increases, and printing ink sometimes accumulates in the cracks to become a cause of edge contamination. From this viewpoint, the bevel width Y is preferably in the range of 70 to 300 μm, and more preferably in the range of 80 to 250 μm. Note that the ranges of the above-mentioned bevel amount and bevel width are independent of the edge shape of the support face 1b of the lithographic printing plate precursor 1.

[0662] Generally, in the end portion of the lithographic printing plate precursor 1, the boundary B of the image recording layer and the support, and the support face 1b also have a bevel, like the image recording layer face 1a.

[0663] The formation of the end portion having the above-mentioned bevel shape can be performed, for example, by adjusting the cutting conditions of the lithographic printing plate precursor.

[0664] Specifically, it can be performed by adjusting the gap, the bite amount, the blade tip angle, and the like of the upper cutting blade and the lower cutting blade in the slitting device used when the lithographic printing plate precursor is cut.

[0665] Figure 4is a conceptual view showing an example of a cutting section of a slitting apparatus. In the slitting apparatus, an upper and lower pair of cutting blades 10, 20 are arranged vertically. The cutting blades 10, 20 are composed of circular blades on a circular plate, and the upper cutting blades 10a and 10b are supported on the same axis by a rotating shaft 11, and the lower cutting blades 20a and 20b are supported on the same axis by a rotating shaft 21. The upper cutting blades 10a and 10b and the lower cutting blades 20a and 20b rotate in opposite directions. A lithographic printing plate precursor 30 is cut to a prescribed width by the upper cutting blades 10a, 10b and the lower cutting blades 20a, 20b. By adjusting the gap of the upper cutting blade 10a and the lower cutting blade 20a and the gap of the upper cutting blade 10b and the lower cutting blade 20b of the cutting section of the slitting apparatus, an end portion having a bevel shape can be formed.

[0666] It is preferable that a part or all of the side surface of the opposite two edges of the above-described lithographic printing plate precursor have a repelling agent. By applying a repelling agent to a part or all of the side surface of the opposite two edges of the end portion having the bevel shape, the edge contamination of the edge end portion over time can be suppressed. As for the repelling agent, there is no particular limitation as long as it can repel ink, but for example, a hydrophilizing agent or a desensitizing solution can be used. Hereinafter, the material used as the repelling agent will be described.

[0667] (Hydrophilizing Agent)

[0668] As one of the preferable modes of the hydrophilizing agent, a phosphoric acid compound can be given. The phosphoric acid compound includes phosphoric acid, salts thereof, esters thereof, and the like. For example, phosphoric acid, metaphosphoric acid, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, sodium dihydrogen phosphate, sodium hydrogen phosphate, potassium dihydrogen phosphate, potassium hydrogen phosphate, sodium tripolyphosphate, potassium pyrophosphate, and sodium hexametaphosphate, and the like can be given. Among them, sodium dihydrogen phosphate, sodium hydrogen phosphate, and sodium hexametaphosphate are preferable.

[0669] As the phosphoric acid compound, a high molecular compound is preferable, and a high molecular compound having a phosphate ester group is more preferable. As the high molecular compound having a phosphate ester group, a polymer containing one or more kinds of monomers having a phosphate ester group in the molecule, or a copolymer containing one or more kinds of monomers having a phosphate ester group and one or more kinds of monomers not containing a phosphate ester group, and a high molecular compound in which a phosphate ester group is introduced to a high molecular compound not having a phosphate ester group by a polymerization reaction, and the like can be given.

[0670] As the monomer having a phosphoric acid or a salt thereof, mono(2- (methyl)acryloyloxyethyl) acid phosphate, mono(3-(methyl)acryloyloxypropyl) acid phosphate, mono(3-(methyl)acryloyloxy-2-hydroxypropyl) acid phosphate, mono(2- (methyl)acryloyloxy-3-hydroxypropyl) acid phosphate, mono(3-chloro-2- (methyl)acryloyloxypropyl) acid phosphate, mono(3-(methyl)acryloyloxy-3- chloro-2-hydroxypropyl) acid phosphate, mono((methyl)acryloyloxy polyethylene glycol) acid phosphate, mono((methyl)acryloyloxy polypropylene glycol) acid phosphate, allyl alcohol acid phosphate, and salts of the phosphoric acid residues thereof, and the like can be given.

[0671] As the monomer not having a phosphoric acid ester group in the above copolymer, a monomer having a hydrophilic group is preferred. As the hydrophilic group, for example, a hydroxyl group, an alkylene oxide structure, an amino group, an ammonium group, and an amide group can be given, with a hydroxyl group, an alkylene oxide structure, or an amide group being preferred, and an alkylene oxide structure having 1 to 20 carbon atoms of an alkylene oxide unit of 2 or 3 being more preferred, and a polyethylene oxide structure having 2 to 10 ethylene oxide units being further preferred. For example, 2-hydroxyethyl acrylate, ethoxydiglycol acrylate, methoxytriglycol acrylate, poly(oxyethylene) methacrylate, N-isopropyl acrylamide, and acrylamide can be given.

[0672] In the high molecular compound having a phosphoric acid ester group, the content of the repeating unit having a phosphoric acid ester group is preferably 1 to 100 mol%, more preferably 5 to 100 mol%, and further preferably 10 to 100 mol%, relative to the total repeating units of the high molecular compound. The mass average molecular weight of the high molecular compound having a phosphoric acid ester group is preferably 5,000 to 1,000,000, more preferably 7,000 to 700,000, and further preferably 10,000 to 500,000.

[0673] As one of the preferred modes of the hydrophilizing agent, a phosphonic acid compound can be given. The phosphonic acid compound includes phosphonic acid, salts thereof, and esters thereof. For example, ethyl phosphonic acid, propyl phosphonic acid, isopropyl phosphonic acid, butyl phosphonic acid, hexyl phosphonic acid, octyl phosphonic acid, dodecyl phosphonic acid, octadecyl phosphonic acid, 2-hydroxyethyl phosphonic acid and sodium or potassium salts thereof, methyl phosphonic acid methyl ester, ethyl phosphonic acid methyl ester, and 2-hydroxyethyl phosphonic acid methyl ester, alkyl phosphonic acid monoalkyl esters such as methyl phosphonic acid methyl ester, ethyl phosphonic acid methyl ester, and 2-hydroxyethyl phosphonic acid methyl ester and sodium or potassium salts thereof, methylene diphosphonic acid, alkylene diphosphonic acids such as vinyl diphosphonic acid and sodium or potassium salts thereof, and polyvinyl phosphonic acid can be given.

[0674] As the phosphonic acid compound, a high molecular compound is preferred. As the high molecular compound preferred as the phosphonic acid compound, a polyvinyl phosphonic acid, a polymer containing one or more monomers having a phosphonic acid group or a phosphonic acid monoester group in the molecule, and a copolymer of one or more monomers having a phosphonic acid group or a phosphonic acid monoester group and one or more monomers not containing either of a phosphonic acid group and a phosphonic acid monoester group can be mentioned.

[0675] As the monomer containing a phosphonic acid group or a salt thereof, a vinyl phosphonic acid, an ethyl phosphonic acid monovinyl ester, a (meth)acrylamidomethyl phosphonic acid, a 3- (meth)acryloyloxypropyl phosphonic acid, and a salt of a phosphonic acid residue thereof can be mentioned.

[0676] As the above high molecular compound, a homopolymer of a monomer having a phosphonic acid ester group or a copolymer of a monomer having a phosphonic acid ester group and a monomer not having a phosphonic acid ester group is preferred. As the monomer not having a phosphonic acid ester group in the above copolymer, a monomer having a hydrophilic group is preferred. As the monomer having a hydrophilic group, for example, a 2-hydroxyethyl acrylate, an ethoxydiglycol acrylate, a methoxytriglycol acrylate, a poly(oxyethylene) methacrylate, an N-isopropyl acrylamide, and an acrylamide can be mentioned.

[0677] In the high molecular compound having a phosphonic acid ester group, the content of the repeating unit having a phosphonic acid ester group is preferably 1 to 100 mol%, more preferably 3 to 100 mol%, and further preferably 5 to 100 mol%, relative to the total repeating units of the high molecular compound.

[0678] The mass average molecular weight of the high molecular compound having a phosphonic acid ester group is preferably 5,000 to 1,000,000, more preferably 7,000 to 700,000, and further preferably 10,000 to 500,000.

[0679] As one of the preferred modes of the hydrophilizing agent, a water-soluble resin can be mentioned. As the water-soluble resin, a water-soluble resin classified as a polysaccharide, a polyvinyl alcohol, a polyvinyl pyrrolidone, a polyacrylamide and a copolymer thereof, a vinyl methyl ether / maleic anhydride copolymer, a vinyl acetate / maleic anhydride copolymer, and a styrene / maleic anhydride copolymer, and the like can be mentioned. As the polysaccharide, a starch derivative (for example, dextrin, enzymatically decomposed dextrin, hydroxypropylated starch, carboxymethylated starch, phosphate esterified starch, polyoxyalkylene grafted starch, and a cyclodextrin), a cellulose (for example, carboxymethyl cellulose, carboxyethyl cellulose, methyl cellulose, hydroxypropyl cellulose, and methylpropyl cellulose, and the like), a carrageenan, an alginic acid, a guar gum, a locust bean gum, a xanthan gum, an arabic gum, a soybean polysaccharide, and the like can be mentioned. As the water-soluble resin, a starch derivative such as dextrin, polyoxyalkylene grafted starch, an arabic gum, carboxymethyl cellulose, or a soybean polysaccharide is preferred.

[0680] As one of the preferable modes of the hydrophilicizing agent, anionic surfactants and nonionic surfactants can be given. As the anionic surfactants, the surfactants described in

[0022] of Japanese Patent Application Publication No. 2014-104631 can be given, and the content is incorporated into the present application specification. As the anionic surfactants, dialkyl sulfosuccinates, alkyl sulfate salts, polyoxyethylene aryl ether sulfate salts, or alkyl naphthalene sulfonates are preferable. As the anionic surfactants, anionic surfactants represented by General Formula (I-A) or General Formula (I-B) are preferable.

[0681] [Chemical Formula 24]

[0682]

[0683] In General Formula (I-A), R 1 represents a linear or branched alkyl group having 1 to 20 carbon atoms, p represents 0, 1, or 2, Ar 1 represents an aryl group having 6 to 10 carbon atoms, q represents 1, 2, or 3, and M1 + represents Na + , K + , Li + , or NH4 + . In the case where p is 2, a plurality of R 1 may be the same as or different from each other.

[0684] In General Formula (I-B), R 2 represents a linear or branched alkyl group having 1 to 20 carbon atoms, m represents 0, 1, or 2, Ar 2 represents an aryl group having 6 to 10 carbon atoms, Y represents a single bond or an alkylene group having 1 to 10 carbon atoms, and R 3 represents a linear or branched alkylene group having 1 to 5 carbon atoms, n represents an integer of 1 to 100, and M2 + represents Na + , K + , Li + , or NH4 + . In the case where m is 2, a plurality of R 2 may be the same as or different from each other, and in the case where n is 2 or more, a plurality of R 3 may be the same as or different from each other.

[0685] In General Formula (I-A) and General Formula (I-B), R 1 and R 2 are preferably CH3, C2H5, C3H7, or C4H9. R 3-CH2-, -CH2CH2-, -CH2CH2CH2- or -CH2CH(CH3)-, more preferably -CH2CH2-. p and m are preferably 0 or 1, more preferably 0. Y is preferably a single bond. n is preferably an integer of 1 to 20.

[0686] As the nonionic surfactant, the surfactants described in

[0031] of Japanese Patent Application Publication No. 2014-104631 can be given, and the content is incorporated into the present application specification. As the nonionic surfactant, polyoxyethylene aryl ether-based and polyoxyethylene-polyoxypropylene block copolymer-based are preferable.

[0687] As the nonionic surfactant, a nonionic surfactant represented by General Formula (II-A) is preferable.

[0688] [Chemical Formula 25]

[0689] (R 4 ) s -Ar 3 -O(CH2CH2O) t (CH2CH(CH3)O) u H (II-A)

[0690] In General Formula (II-A), R 4 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, s represents 0, 1 or 2, Ar 3 represents an aryl group having 6 to 10 carbon atoms, t and u each represent an integer of 0 to 100, and both of t and u are not 0. In the case where s is 2, the plurality of R4may be the same as each other or different from each other.

[0691] In addition, as the hydrophilic agent, an organic resin fine particle (for example, microgel) can be used. The microgel is a reactive or non-reactive resin particle dispersed in an aqueous medium. The microgel preferably has a polymerizable group in the particle or on the surface of the particle.

[0692] The coating liquid containing the hydrophilic agent is preferably in the form of an aqueous solution in which the hydrophilic agent is dissolved or dispersed in a medium mainly containing water. The content of the hydrophilic agent in the coating liquid containing the hydrophilic agent is preferably 0.05 to 50% by mass, more preferably 0.1 to 30% by mass. The viscosity of the coating liquid containing the hydrophilic agent is preferably 0.5 to 1000 mPa-s, more preferably 1 to 100 mPa-s at 25°C. The surface tension of the coating liquid containing the hydrophilic agent is preferably 25 to 70 mN / m, more preferably 40 to 65 mN / m at 25°C.

[0693] The coating liquid containing the hydrophilic agent can contain, in addition to the hydrophilic agent, an organic solvent, a plasticizer, a preservative, an antifoaming agent, and an inorganic salt such as a nitrate and a sulfate.

[0694] (desensitizing solution)

[0695] As the desensitizing solution, an aqueous solution containing at least one of a hydrophilic organic high molecular compound, hexametaphosphoric acid and a salt thereof, and phytic acid and a salt thereof can be mentioned. As a specific hydrophilic organic high molecular compound, gum arabic, dextrin, an alginate such as sodium alginate, a water-soluble cellulose such as carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, a water-soluble copolymer containing an acrylamide unit, polyacrylic acid, a copolymer containing an acrylic acid unit, polymethacrylic acid, a copolymer containing a methacrylic acid unit, a copolymer of vinyl methyl ether and maleic anhydride, a copolymer of vinyl acetate and maleic anhydride, phosphoric acid-modified starch, and the like can be mentioned, of which gum arabic is preferred because of its strong desensitizing effect. Two or more of these hydrophilic high molecular compounds can be used in combination as needed, at a concentration of about 1 to 40% by weight, more preferably 3 to 30% by weight.

[0696] As a specific hexametaphosphoric acid salt, an alkali metal salt or an ammonium salt of hexametaphosphoric acid can be mentioned. As the alkali metal salt or the ammonium salt of hexametaphosphoric acid, sodium hexametaphosphate, potassium hexametaphosphate, ammonium hexametaphosphate, and the like can be mentioned. As a specific phytic acid or a salt thereof, alkali metal salts such as sodium salt, potassium salt, lithium salt, ammonium salt, amine salt, and the like are mentioned. As the amine salt, diethylamine salt, triethylamine salt, n-propylamine salt, di-n-propylamine salt, tri-n-propylamine salt, n-butylamine salt, n-pentylamine salt, n-hexylamine salt, laurylamine salt, ethylenediamine salt, trimethylenediamine salt, tetramethylenediamine salt, pentamethylenediamine salt, hexamethylenediamine salt, ethanolamine salt, diethanolamine salt, triethanolamine salt, allylamine salt, aniline salt, and the like can be mentioned. The phytic acid salt can be a normal salt in which the hydrogens of 12 acids are all substituted, a hydrogen salt (acidic salt) in which the hydrogens of a part of the acids are substituted, and any of a mono salt containing one salt group, a complex salt containing two or more salt groups as a component can be used. These compounds can be used alone or in combination of two or more.

[0697] In the desensitizing solution used in the present embodiment, it is preferable to further contain a metal salt of a strong acid, whereby the desensitizing effect can be improved. As the metal salt of a strong acid, for example, sodium salt, potassium salt, magnesium salt, calcium salt, and zinc salt of nitric acid, sodium salt, potassium salt, magnesium salt, calcium salt, and zinc salt of sulfuric acid, sodium salt, potassium salt, magnesium salt, calcium salt, and zinc salt of chromic acid, and sodium fluoride and potassium fluoride can be given. Two or more of these metal salts of a strong acid can be used in combination, and the amount thereof is preferably about 0.01 to 5% by weight based on the total weight of the desensitizing solution. In the desensitizing solution used in the present application, the pH is adjusted to the acidic range, more preferably to 1 to 5, and most preferably to 1.5 to 4.5. Therefore, in the case where the pH of the aqueous phase is not acidic, an acid is further added to the aqueous phase. As the acid to be added as the pH adjuster, for example, inorganic acids such as phosphoric acid, sulfuric acid, and nitric acid, and organic acids such as citric acid, tannic acid, malic acid, acetic acid, lactic acid, oxalic acid, p-toluenesulfonic acid, and organic phosphonic acid can be given. Among them, phosphoric acid is particularly excellent because it not only functions as the pH adjuster but also has an effect of enhancing the desensitizing effect, and is preferably contained in an amount of 0.01 to 20% by weight, and most preferably 0.1 to 10% by weight, relative to the total weight of the desensitizing solution.

[0698] In the desensitizing solution used in the present embodiment, it is preferable to contain a wetting agent and / or a surfactant, whereby the coatability of the desensitizing solution can be improved. As the specific wetting agent, a lower polyhydric alcohol is preferable, and for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, glycerol, sorbitol, pentaerythritol, and the like can be given, and glycerol is particularly preferable. Further, as the surfactant, for example, nonionic surfactants such as polyoxyethylene alkyl phenyl ether, polyoxyethylene polyoxypropylene block copolymer, and the like, anionic surfactants such as fatty acid salts, alkyl sulfate salts, alkyl benzene sulfonic acid salts, alkyl naphthalene sulfonic acid salts, dialkyl sulfosuccinate salts, alkyl phosphate salts, naphthalene sulfonic acid formalin condensate, and the like, and amphoteric surfactants such as betaine type, glycine type, alanine type, and sulfobetaine type can be given. These wetting agent and / or surfactant are contained in an amount of about 0.5 to 10% by weight, and more preferably 1 to 5% by weight, relative to the total weight of the desensitizing solution. In the desensitizing solution used in the present application, a filler such as silica, talc, clay, and the like can be further contained in an amount of at most 2% by weight, and a dye or pigment and the like can be further contained in an amount of at most 1% by weight.

[0699] As described above, the desensitizing solution used in the present embodiment contains a hydrophilic aqueous solution, but in consideration of the case where an adverse effect on the image recording layer occurs, for example, an emulsified desensitizing solution as described in each of U.S. Patent No. 4253999, U.S. Patent No. 4268613, U.S. Patent No. 4348954, and the like can also be used.

[0700] As the ink repellent, for example, HN-G5 (manufactured by Fujifilm Corporation) can be used.

[0701] (Method of applying ink repellent)

[0702] The method of applying the ink repellent is not particularly limited. Figure 7 is a view illustrating the method of applying the ink repellent. As shown in Figure 7 , the coating liquid containing the ink repellent can be applied by the wire bar 138. In addition, in Figure 7 , in order to explain the method of applying the ink repellent, the lithographic printing plate precursor 100a having the outermost surface 122 of the specific structure layer side as a reference is simply described, and the shape of the end portion is not described. When the ink repellent is applied with the wire bar 138, first, the coating liquid containing the ink repellent is applied to the wire bar 138. The wire bar 138 is moved so that the wire bar 138 to which the coating liquid is applied is moved along the end surface 120 (the side surface of the aluminum support) of the lithographic printing plate precursor 100a. As the moving speed of the wire bar 138, for example, it can be moved at 20 mm / s. After the application, the drying of the coating liquid is performed. As the drying condition, for example, it can be dried by blowing the wind at 80°C at a wind speed of 6 m / s for 30 seconds.

[0703] In addition, as the size of the wire bar, it can be appropriately changed according to the thickness of the aluminum support of the lithographic printing plate precursor 100a, but for example, in the case where the thickness of the aluminum support is 0.3 mm, the 10th wire bar can be used.

[0704] Further, when the coating liquid is applied, as shown in Figure 7 , the wire bar 138 can be applied at an inclination angle θ with respect to the end surface 120 of the lithographic printing plate precursor 100a.

[0705] As the method of applying the ink repellent to a part or all of the side surface of the opposite two edges of the above-described lithographic printing plate precursor, the method described in Japanese Patent No. 6628949 can be preferably used.

[0706] [Method of manufacturing negative type lithographic printing plate]

[0707] A method of manufacturing a negative type lithographic printing plate (hereinafter, also referred to as "lithographic printing plate") according to the present application will be described using the laminate according to the present application.

[0708] The method for producing a lithographic printing plate is not particularly limited, but preferably includes: a step of taking out the lithographic printing plate precursor from the laminate (platemaking step) ; a step of image-exposing the lithographic printing plate precursor (exposure step) ; and a step of supplying at least one of a printing ink and a dampening liquid and removing the unexposed portion of the image-recording layer in the above lithographic printing plate precursor (on-press developing step).

[0709] 〔Platemaking step〕

[0710] The platemaking step is a step of taking out the lithographic printing plate precursor from the laminate, and is usually preferably performed in a setting machine.

[0711] 〔Exposure step〕

[0712] The image exposure is preferably performed by a method of scanning exposure of digital data by infrared laser light or the like.

[0713] The wavelength of the exposure light source is preferably 750 to 1,400 nm. As the light source having a wavelength of 750 nm to 1,400 nm, a solid laser and a semiconductor laser that radiate infrared rays are preferable. The exposure mechanism can be any one of an inner drum system, an outer drum system, a flatbed system, and the like.

[0714] The exposure step can be performed by a known method using a plate making machine or the like. Also, a printing machine equipped with an exposure device can be used, and the image exposure can be performed on the printing machine after the lithographic printing plate precursor is mounted on the printing machine.

[0715] 〔On-press developing step〕

[0716] The method for producing a lithographic printing plate according to the present application preferably includes the on-press developing step of supplying at least one of a printing ink and a dampening liquid and removing the unexposed portion of the image-recording layer in the above lithographic printing plate precursor.

[0717] Also, the method for producing a lithographic printing plate according to the present application can be performed by a method of developing with a developing solution (developing solution treatment method).

[0718] Hereinafter, the on-press developing method will be described.

[0719] - On-press developing method -

[0720] In the on-press development method, if the lithographic printing plate precursor is not subjected to any development treatment after the exposure of the image and is supplied with printing ink and dampening solution on a printing machine to start printing, the non-exposed portions of the lithographic printing plate precursor are removed at an early stage in the printing process, and a non-image area is formed by exposure of the surface of the hydrophilic support. As the printing ink and dampening solution, known printing ink and dampening solution for lithographic printing can be used. The first to be supplied to the surface of the printing plate precursor can be either printing ink or dampening solution, but from the viewpoint of preventing contamination of the removed image recording layer components by the dampening solution, it is preferable to supply printing ink first.

[0721] Thus, the lithographic printing plate precursor is subjected to on-press development on an offset printing machine and is directly used for multi-printing.

[0722] The method for producing a lithographic printing plate according to the present application can include other known procedures in addition to the above procedures. As the other procedures, for example, there can be mentioned a plate inspection procedure for confirming the position or orientation of the lithographic printing plate precursor before each procedure, a confirmation procedure for confirming the printed image after the on-press development procedure, and the like.

[0723] Examples

[0724] Hereinafter, the present application will be described in detail by way of examples, but the present application is not limited to these. In the examples, the term "%" and "parts" means "mass %" and "mass parts", respectively, unless otherwise specified. In the high molecular compound, the molecular weight is the mass average molecular weight (Mw) and the ratio of the structural repeating unit is the mole percentage, unless otherwise specified. The mass average molecular weight (Mw) is a value determined as a polystyrene conversion value based on the gel permeation chromatography (GPC) method.

[0725] [Examples 1 to 36 and Comparative Examples 1 and 2]

[0726] [Production of Support 1]

[0727] A support 1 was produced by subjecting an aluminum plate (aluminum alloy plate) of 1S having a thickness of 0.3 mm to the following (F-a) to (F-g) treatments. In addition, water washing treatment was performed between all the treatment procedures, and drainage was performed by a nip roll after the water washing treatment.

[0728] (F-a) Alkaline etching treatment

[0729] Etching treatment was performed by spraying an aqueous caustic soda solution having a caustic soda concentration of 26 mass% and an aluminum ion concentration of 6.5 mass% to the aluminum plate at a temperature of 70°C using a sprayer. Then, the amount of aluminum dissolved from the surface subjected to the electrochemical roughening treatment was 5 g / m 2 .

[0730] (Fb) used an acidic aqueous solution for decontamination treatment.

[0731] An acidic aqueous solution with a temperature of 30°C and a sulfuric acid concentration of 150 g / L was sprayed onto the aluminum plate for 3 seconds using a sprayer and then used for decontamination treatment.

[0732] (Fc) Electrochemical roughening treatment

[0733] Electrochemical roughening treatment was performed using an electrolyte solution with a hydrochloric acid concentration of 14 g / L, an aluminum ion concentration of 13 g / L, and a sulfuric acid concentration of 3 g / L, employing alternating current. The electrolyte temperature was 30°C. The aluminum ion concentration was adjusted by adding aluminum chloride.

[0734] The alternating current waveform is a symmetrical sine wave with positive and negative phases, and a frequency of 50 Hz. The ratio of the anode reaction time to the cathode reaction time in one cycle of the alternating current is 1:1. The current density, expressed as the peak current of the alternating current waveform, is 75 A / dm³. 2 Furthermore, the electrical charge, calculated as the total charge generated by the aluminum plate participating in the anode reaction, is 450 C / dm. 2 Regarding electrolytic treatment, with a 4-second energizing interval, at 112.5C / dm³ 2 The process was performed in four stages. A carbon electrode was used as the counter electrode in the aluminum plate.

[0735] (Fd) alkaline etching treatment

[0736] Etching was performed on an aluminum plate by spraying an aqueous solution of caustic soda (5% by mass) and aluminum ions (0.5% by mass) using a sprayer at 45°C. The dissolved aluminum content on the surface after electrochemical roughening was 0.2 g / m². 2 .

[0737] (Fe) was treated with an acidic aqueous solution for decontamination.

[0738] An acidic aqueous solution with a sulfuric acid concentration of 170 g / L and an aluminum ion concentration of 5 g / L was sprayed onto the aluminum plate for 3 seconds using a sprayer and then used for decontamination treatment.

[0739] (Ff) Stage 1 Anodizing Treatment

[0740] Using based Figure 6 The DC electrolytic anodizing apparatus shown was used for the first stage of anodizing. A 150 g / L phosphoric acid aqueous solution was used as the electrolyte, at a liquid temperature of 35°C and a current density of 4.5 A / dm³. 2 Anodizing was performed under specific conditions, resulting in a film thickness of 1 g / m³. 2 The anodic oxide film.

[0741] (Fg) Stage 2 Anodizing Treatment

[0742] Using based Figure 6 The DC electrolytic anodizing apparatus shown underwent the second stage of anodizing. A 170 g / L sulfuric acid aqueous solution was used as the electrolyte, and the conditions were: a liquid temperature of 50°C and a current density of 13 A / dm³. 2 Anodizing was performed under specific conditions, resulting in a film thickness of 2.1 g / m³. 2 An anodized film was formed. Then, a spray-based water wash was performed. The average diameter of the micropores in support 1 was 40 nm.

[0743] The value of lightness L* in the L*a*b* color system of the anodic oxide film surface of support 1 is 83.7.

[0744] The average diameter of the large-diameter hole at the surface of the anodic oxide film is 26 nm, and the depth from the surface of the anodic oxide film is 160 nm.

[0745] The average diameter of the small-diameter aperture at the connection point is 10 nm, and the depth from the connection point is 800 nm.

[0746] <Construction of Support Body 2>

[0747] -Alkali etching treatment-

[0748] Etching was performed on an aluminum plate at 55°C by spraying an aqueous solution of caustic soda (26% by mass) and aluminum ions (6.5% by mass). This was followed by a spray-based water wash. The aluminum dissolution rate on the surface after electrochemical roughening was then 3 g / m². 2 .

[0749] - Decontamination treatment using acidic aqueous solution (first decontamination treatment) -

[0750] Next, a decontamination treatment was performed using an acidic aqueous solution. The acidic aqueous solution used was a 170 g / L sulfuric acid solution at a temperature of 30°C. The acidic aqueous solution was sprayed onto the aluminum plate using a sprayer and the decontamination was performed for 3 seconds. Then, a water rinse was performed.

[0751] -Electrochemical roughening treatment-

[0752] Next, electrochemical roughening treatment was performed using a hydrochloric acid electrolyte and alternating current. The electrolyte temperature was 40°C. The alternating current waveform was a symmetrical sine wave with positive and negative phases and a frequency of 50 Hz. Furthermore, the total charge, calculated based on the charge participating in the anode reaction on the aluminum plate, was 300 C / dm³. 2 The process was carried out under specific conditions. A carbon electrode was used as the counter electrode in the aluminum plate. Then, a water washing process was performed.

[0753] -Alkali etching treatment-

[0754] At 35°C, an aqueous solution of caustic soda with a concentration of 5% by mass and an aluminum ion concentration of 0.5% by mass was sprayed onto an electrochemically roughened aluminum plate using a sprayer, with an etching rate of 0.1 g / m. 2 The etching process was performed as follows. Then, a water washing process was carried out.

[0755] -Decontamination treatment using acidic aqueous solution-

[0756] Next, a decontamination treatment was performed using an acidic aqueous solution. The acidic aqueous solution used was a 170 g / L sulfuric acid solution at a temperature of 30°C. The acidic aqueous solution was sprayed onto the aluminum plate using a sprayer and the decontamination was performed for 3 seconds. Then, a water rinse was performed.

[0757] -Anodizing Treatment-

[0758] Under conditions of sulfuric acid concentration of 170 g / L and liquid temperature of 40 °C, using direct current, the anodic oxide film thickness is 3 g / m. 2 The process involved anodizing.

[0759] The average diameter of the micropores in support 2 is 15 nm.

[0760] The value of lightness L* in the L*a*b* color system of the anodic oxide film surface of support 2 is 78.5.

[0761] <Construction of Support Body 3>

[0762] The support body 3 was manufactured by performing the following (Ja) to (Jm) processes on an aluminum plate (aluminum alloy plate) of material 1S with a thickness of 0.3 mm. In addition, a water washing process was performed between all processing steps, and the liquid was drained by clamping rollers after the water washing process.

[0763] (Ja) Mechanical roughening treatment (brush texture method)

[0764] Use such as Figure 5 The apparatus shown contains a suspension of pumice powder (specific gravity 1.1 g / cm³). 3 While being supplied to the surface of the aluminum plate as an abrasive slurry, it undergoes mechanical roughening treatment via a rotating stiff-bristled brush. Figure 5 In the diagram, 31 is an aluminum plate, 32 and 34 are roller brushes (in this embodiment, they are stiff bristle brushes), 33 is grinding slurry, and 35, 36, 37 and 38 are support rollers.

[0765] In the mechanical roughening process, the median particle size (μm) of the abrasive material was set to 30μm, the number of brushes was set to 4, and the brush rotation speed (rpm) was set to 250rpm. The stiff bristle tuft brush was made of 6 / 10 nylon, with bristle diameter of 0.3mm and bristle length of 50mm. The brush was constructed by drilling holes and densely packing bristles into a φ300mm stainless steel sleeve. The distance between the two support rollers (φ200mm) at the bottom of the stiff bristle tuft brush was 300mm. The load on the drive motor that pressed the stiff bristle tuft brush until it rotated was increased by 10kW compared to the load before pressing the brush against the aluminum plate. The rotation direction of the brush was the same as the movement direction of the aluminum plate.

[0766] (Jb) Alkali etching treatment

[0767] Etching was performed on an aluminum plate by spraying an aqueous solution of caustic soda (26% by mass) and aluminum ions (6.5% by mass) using a sprayer at 70°C. The aluminum dissolution rate on the surface after electrochemical roughening was then 10 g / m². 2 .

[0768] (Jc) used acidic aqueous solution for decontamination treatment.

[0769] The waste liquid of nitric acid used in the next electrochemical roughening process, which involves spraying the aluminum plate with a liquid temperature of 35°C for 3 seconds using a sprayer, was used as an acidic aqueous solution and was then treated to remove contaminants.

[0770] (Jd) used electrochemical roughening treatment with nitric acid aqueous solution.

[0771] Electrochemical roughening treatment was performed continuously using a 60Hz AC voltage. The electrolyte was an aqueous solution of 10.4 g / L nitric acid with aluminum nitrate added to adjust the aluminum ion concentration to 4.5 g / L, and the solution temperature was 35°C. The AC power supply waveform is as follows. Figure 1 The waveform shown, with a current value reaching its peak value from zero in 0.8 msec (tp), a duty ratio of 1:1, and a trapezoidal rectangular wave AC current, was electrochemically roughened using a carbon electrode as the counter electrode. Ferrite was used as the auxiliary anode. Regarding the electrolytic cell, [the following is a description of the electrolytic cell:] A trapezoidal rectangular wave AC current was used. Figure 2 The electrolytic cell shown. The current density, expressed as peak current, is 30 A / dm³. 2 This causes 5% of the current flowing from the power source to be diverted to the auxiliary anode. (Electricity (C / dm³)) 2 The total charge when using an aluminum plate as the anode is 185 C / dm. 2 .

[0772] (Je) alkaline etching treatment

[0773] Etching treatment was performed by spraying an aqueous caustic soda solution having a caustic soda concentration of 27 mass% and an aluminum ion concentration of 2.5 mass% at 50°C using a spray device. The aluminum dissolution amount was 3.5 g / m 2 .

[0774] (J-f) Stain removal treatment using an acidic aqueous solution

[0775] An aqueous solution having a liquid temperature of 30°C, a sulfuric acid concentration of 170 g / L, and an aluminum ion concentration of 5 g / L was sprayed for 3 seconds using a spray device as an acidic aqueous solution, and a stain removal treatment was performed.

[0776] (J-g) Electrochemical roughening treatment using an aqueous hydrochloric acid solution

[0777] An electrochemical roughening treatment was continuously performed using an alternating current voltage of 60 Hz. An electrolyte solution was used in which an aluminum ion concentration was adjusted to 4.5 g / L in an aqueous solution of hydrochloric acid 6.2 g / L at a liquid temperature of 35°C. An alternating current power waveform was a waveform shown in Figure 1 , and a time tp from zero to a peak value of a current value was 0.8 msec, a duty ratio was 1:1, a trapezoidal rectangular wave alternating current, a carbon electrode was used as a counter electrode, and an electrochemical roughening treatment was performed. A supplementary anode was a ferrite. As for an electrolytic cell, an electrolytic cell shown in Figure 2 was used. A current density was 25 A / dm 2 in terms of a peak value of a current, and an electric quantity (C / dm 2 ) in the hydrochloric acid electrolysis was 63 C / dm 2 in terms of a total of an electric quantity when an aluminum plate was used as an anode.

[0778] (J-h) Alkaline etching treatment

[0779] Etching treatment was performed by spraying an aqueous caustic soda solution having a caustic soda concentration of 5 mass% and an aluminum ion concentration of 0.5 mass% at 60°C using a spray device. The aluminum dissolution amount was 0.2 g / m 2 .

[0780] (J-i) Stain removal treatment using an acidic aqueous solution

[0781] An aqueous solution of a waste liquid (sulfuric acid concentration 170 g / L and aluminum ion concentration 5 g / L) generated in an anodizing treatment step at a liquid temperature of 35°C was sprayed for 4 seconds using a spray device as an acidic aqueous solution, and a stain removal treatment was performed.

[0782] (J-j) First-stage anodizing treatment

[0783] An anodizing treatment was performed using a power source based on Figure 6The DC electrolytic anodizing apparatus shown underwent the first stage of anodizing. A 170 g / L sulfuric acid aqueous solution was used as the electrolyte, and the conditions were: a liquid temperature of 50°C and a current density of 30 A / dm³. 2 Anodizing was performed under specific conditions, resulting in a film thickness of 0.3 g / m². 2 The anodic oxide film.

[0784] (Jk) Hole Enlargement Treatment

[0785] The aluminum plate that had undergone anodizing was immersed in an aqueous solution of caustic soda with a concentration of 5% by mass and an aluminum ion concentration of 0.5% by mass at 40°C for 3 seconds to perform a hole-enlarging treatment.

[0786] (J-1) Stage 2 Anodizing Treatment

[0787] Using based Figure 6 The DC electrolytic anodizing apparatus shown underwent the second stage of anodizing. A 170 g / L sulfuric acid aqueous solution was used as the electrolyte, and the conditions were: a liquid temperature of 50°C and a current density of 13 A / dm³. 2 Anodizing was performed under specific conditions, resulting in a film thickness of 2.1 g / m³. 2 The anodic oxide film.

[0788] exist Figure 6 In the anodizing apparatus 410 shown, the aluminum plate 416 is as follows: Figure 6 The aluminum plate 416 is conveyed as indicated by the middle arrow. In the power supply tank 412 containing electrolyte 418, the aluminum plate 416 is charged (+) by the power supply electrode 420. Furthermore, the aluminum plate 416 is conveyed upwards in the power supply tank 412 by roller 422, then downwards by clamping roller 424, and finally conveyed to the electrolytic treatment tank 414 containing electrolyte 426, and then horizontally by roller 428. Next, the aluminum plate 416 is charged (-) by the electrolytic electrode 430, thereby forming an anodized film on its surface. The aluminum plate 416, leaving the electrolytic treatment tank 414, is then conveyed to subsequent processes. In the aforementioned anodizing apparatus 410, a direction-changing mechanism is formed by rollers 422, clamping rollers 424, and rollers 428. In the inter-tank section between the power supply tank 412 and the electrolytic treatment tank 414, aluminum plates 416 are conveyed in a mountain-shaped and inverted U-shaped configuration via rollers 422, 424, and 428. The power supply electrode 420 and the electrolytic electrode 430 are connected to a DC power supply 434.

[0789] (Jm) hydrophilic treatment

[0790] To ensure the hydrophilicity of the non-image area, the aluminum plate was subjected to silicate treatment by immersing it in a 2.5% (w / w) sodium silicate solution (No. 3) at 50°C for 7 seconds. The Si deposition rate was 8.5 mg / m².2 The average diameter of the micropores was 30 nm.

[0791] The value of the lightness L* in the L*a*b* color system of the anodized film surface of the support 3 was 72.3.

[0792] The average diameter of the large-diameter pore portion at the anodized film surface was 26 nm, and the depth from the anodized film surface was 100 nm.

[0793] The average diameter of the small-diameter pore portion at the communication position was 10 nm, and the depth from the communication position was 1300 nm.

[0794] <Formation of the base coat 1>

[0795] The base coat 1 was formed by applying a base coat coating solution (1) of the following composition to the support so that the dry coating amount would be 0.03 g / m 2

[0796] (Base coat coating solution (1))

[0797] Polyacrylic acid aqueous solution (40 mass %) (Jurymer AC-10S, manufactured by TOAGOSEI CO., LTD.) 3.0 parts

[0798] Water 27.0 parts

[0799] <Formation of the base coat 2>

[0800] The base coat 2 was formed by applying a base coat coating solution (2) of the following composition to the support so that the dry coating amount would be 26 mg / m 2

[0801] (Base coat coating solution (2))

[0802]

[0803]

[0804] [Chemical Formula 26]

[0805]

[0806] The values on the lower right side of the parentheses in each structural unit in the above base coat compound (2) represent the mass ratio, and the value on the lower right side of the parentheses of the ethyleneoxy unit represents the number of repetitions.

[0807] <Formation of the image recording layer 1>

[0808] The image recording layer coating solution (1) of the following composition was bar-coated, and then baked at 110°C for 40 seconds to form an image recording layer having a dry weight of 0.9 g / m​​2 image recording layer 1.

[0809] (Image recording layer coating liquid (1))

[0810]

[0811]

[0812] *1: The polymer emulsion A is a polymer particle of a graft copolymer of poly(ethylene glycol) methyl ether methacrylate / styrene / acrylonitrile = 10:9:81, and is a dispersion containing 24 mass% of the particle in a solvent of n-propanol / water at a mass ratio of 80 / 20. Also, the volume average particle diameter thereof is 193 nm.

[0813] *2: Klucel E refers to hydroxypropyl cellulose available from Hercules Inc.

[0814] *3: A polymerizable compound having a concentration of 80 mass% in a 2-butanone solution obtained by reacting DESMODUR (registered trademark) N100 and hydroxyethyl acrylate and pentaerythritol acrylate at a molar ratio of 1 : 1.5: 1.5.

[0815] *4: Dipentaerythritol pentaacrylate (Sartomer Company)

[0816] *5: A compound represented by the following Formula 1

[0817] *6: A compound represented by the following Formula 2

[0818] [Chemical Formula 27]

[0819]

[0820] *7: Black-XV (the following compound, manufactured by Yamamoto Chemicals Inc.)

[0821] *8: A xylene / methoxypropyl acetate solution containing a modified polydimethylsiloxane copolymer at a concentration of 25 mass% (manufactured by BYK Chemie Inc.)

[0822] [Chemical Formula 28]

[0823]

[0824] <Formation of image recording layer 2>

[0825] After a bar coating of an image recording layer coating liquid (2) of the following composition, drying was performed at 120°C for 40 seconds to form an image recording layer having a dry weight of 1.0 g / m2 The image recording layer 2.

[0826] (Image recording layer coating liquid (2))

[0827] The image recording layer coating liquid (2) contains each of the following components, and is prepared with a mixed solvent of 1-methoxy-2-propanol (MFG) : methyl ethyl ketone (MEK) : methanol = 4 : 4 : 1 (mass ratio) in a manner that the solid content becomes 6 mass%.

[0828]

[0829] *1: Binder polymer P-2: Polyvinyl acetal, S-LEC BL10 manufactured by SEKISUI CHEMICAL CO., LTD.

[0830] [Chemical Formula 29]

[0831]

[0832] Formation of image recording layer 3

[0833] The image recording layer coating liquid (3) of the following composition was bar coated and dried at 100°C for 60 seconds to form the image recording layer 3 having a thickness of 1.2 μm.

[0834] The image recording layer coating liquid (3) was obtained by mixing and stirring the following photosensitive solution (1) and microgel solution (1) immediately before coating.

[0835] (Photosensitive solution (1))

[0836]

[0837]

[0838] Preparation of microgel (1)

[0839] The preparation method of the microgel (1) used in the above microgel solution is shown below.

[0840] Preparation of polyvalent isocyanate compound (1)

[0841] The polyvalent isocyanate compound (1) was prepared in the same manner as in the <Preparation of polyvalent isocyanate compound (1)> in

[0517] to

[0518] of International Publication No. 2019 / 045084.

[0842] Preparation of microgel (1)

[0843] Microgels (1) were prepared in the same manner as in <Preparation of microgels (4)> in

[0519] to

[0521] of International Publication No. 2019 / 045084.

[0844] <Synthesis of binder polymer (6)>

[0845] Binder polymer (6) was synthesized in the same manner as in <Synthesis of binder polymer (6)> in

[0522] to

[0523] of International Publication No. 2019 / 045084.

[0846] <Synthesis of binder polymer (7)>

[0847] Binder polymer (7) was synthesized in the same manner as in <Synthesis of binder polymer (7)> in

[0524] to

[0525] of International Publication No. 2019 / 045084.

[0848] [Chemical Formula 30]

[0849]

[0850] [Chemical Formula 31]

[0851]

[0852] <Formation of protective layer 1>

[0853] After bar coating a protective layer coating liquid (1) of the following composition on the image recording layer, a dry coating amount of 0.15 g / m2of a protective layer was formed by drying at 120°C for 60 seconds. 2

[0854] (Protective layer coating liquid (1))

[0855] • Inorganic layered compound dispersion liquid (1) (below): 1.5 parts

[0856] • Hydrophilic polymer (1) (the following structure, Mw: 30,000) (solid content): 0.03 parts

[0857] • Polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., CKS50, sulfonic acid-modified, saponification degree of 99 mol% or more, polymerization degree of 300) 6 mass% aqueous solution: 0.10 parts

[0858] • Polyvinyl alcohol (manufactured by Kuraray Co., Ltd., PVA-405, saponification degree of 81.5 mol%, polymerization degree of 500) 6 mass% aqueous solution: 0.03 parts

[0859] ​• Surfactant (EMALEX 710, manufactured by NIHON EMULSION Co., Ltd., the following structure) 1 mass% aqueous solution): 0.86 parts

[0860] • Ion exchange water: 6.0 parts

[0861] [Chemical Formula 32]

[0862]

[0863] (Preparation of inorganic layered compound dispersion liquid (1))

[0864] To 193.6 parts of ion exchange water, 6.4 parts of synthetic mica SOMASIF ME-100 (manufactured by Co-op Chemical Co., Ltd.) was added, and dispersed using a homogenizer to a volume average particle diameter (laser scattering method) of 3 μm. The aspect ratio of the obtained dispersed particles was 100 or more.

[0865] (Formation of protective layer 2)

[0866] After bar coating of a protective layer coating liquid (2) of the following composition on the image recording layer, drying was performed at 120°C for 60 seconds to form a protective layer having a dry coating weight of 0.10 g / m 2 .

[0867] (Protective layer coating liquid (2))

[0868]

[0869] *1: Methyl cellulose (methoxyl substitution degree 1.8), METOLOSE (registered trademark) SM04, manufactured by Shin-Etsu Chemical Co., Ltd.,

[0870] *2: Aqueous dispersion of styrene acrylic resin particles, glass transition temperature Tg 103°C, softening point 225°C, Fine Sphere (registered trademark) FS-102 (21 mass%) manufactured by Nippon paint Industrial Coatings Co., LTD.

[0871] *3: Di-2-ethylhexyl-sodium sulfosuccinate, RAPISOL A-80 (80 mass%) manufactured by NOF CORPORATION

[0872] (Formation of protective layer 3)

[0873] After bar coating of a protective layer coating liquid (3) of the following composition on the image recording layer, drying was performed at 120°C for 60 seconds to form a protective layer having a dry weight of 0.15 g / m2 a protective layer 3.

[0874] (protective layer coating liquid (3))

[0875] The protective layer coating liquid (3) contains each of the following components and is prepared with ion exchange water so that the solid content becomes 6 mass%.

[0876]

[0877] *1: WP-1: Polyvinyl alcohol, Mowiol 4-88 manufactured by Sigma-Aldrich Co. LLC.

[0878] *2: WP-2: Polyvinyl alcohol, Mowiol 8-88 manufactured by Sigma-Aldrich Co. LLC.

[0879] *3: WP-3: Resin described below (Mw 52,000)

[0880] [Chemical Formula 33]

[0881]

[0882] [Manufacture of Lithographic Printing Plate Precursor]

[0883] The lithographic printing plate precursors of Examples 1 to 36 and the lithographic printing plate precursors of Comparative Examples 1 and 2 were manufactured by combining the above-mentioned support, the primer layer, the image recording layer, and the protective layer as described in Table 1.

[0884] With respect to the lithographic printing plate precursors of Examples 25, 26, 32 to 36, the above-mentioned support, the primer layer, the image recording layer, and the protective layer were combined as described in Table 1, and further, the following backcoat layer 1 was formed to manufacture.

[0885] [Formation of Backcoat Layer 1]

[0886] The backcoat layer coating liquid (1) of the following composition was bar coated on the side of the support opposite to the side of the specific structure layer, and dried at 100°C for 30 seconds to form the backcoat layer 1 having a thickness of 1.2 μm.

[0887] (Backcoat Layer Coating Liquid (1))

[0888]

[0889]

[0890] The arithmetic average height Sa of the outermost surface (A surface) on the side of at least one layer containing the above-described infrared absorber with reference to the above-described support and the arithmetic average height Sa of the outermost surface (B surface) on the side opposite to the side of at least one layer containing the above-described infrared absorber with reference to the above-described support are also described in Table 1. The arithmetic average height Sa was evaluated in the following manner.

[0891] <Measurement of Arithmetic Average Height Sa>

[0892] The measurement of the arithmetic average height Sa was performed in accordance with the method described in ISO 25178. That is, the measurement was performed on three or more places selected from the same sample using a microtopographer MM3200-M100 manufactured by Ryoka Systems Inc., and the average value thereof was taken as the arithmetic average height Sa. As for the measurement range, a 1 cm x 1 cm range selected at random from the surface of the sample was measured.

[0893] Further, the average particle diameter involved in the particle was a volume average particle diameter, and was measured in the above-described manner.

[0894] The HOMO of the specific infrared absorber is also described in Table 1. The HOMO was measured in the above-described manner.

[0895] [Table 1]

[0896]

[0897] [Table 2]

[0898] Table 1 (continued)

[0899]

[0900] [Table 3]

[0901] Table 1 (continued)

[0902]

[0903] [Table 4]

[0904] Table 1 (continued)

[0905]

[0906] In Table 1, the added layer of the specific infrared absorber or particle indicates a structure layer (image recording layer, protective layer, back coating layer) of the lithographic printing plate precursor containing the specific infrared absorber or particle. The structure layer can be formed by preparing a coating liquid by adding the specific infrared absorber or particle to a coating liquid of the corresponding structure layer and coating.

[0907] In Table 1, as to the specific infrared absorber, it is described whether or not the specific infrared absorber is contained in the image recording layer, the protective layer.

[0908] The following describes the parent nucleus structure and counter anion Za constituting the specific infrared absorber described in Table 1.

[0909] [Chemical Formula 34]

[0910]

[0911] [Chemical Formula 35]

[0912]

[0913] [Chemical Formula 36]

[0914]

[0915] In addition, IR-1C, IR-2C are not included in the parent nucleus structure of the specific infrared absorber, but are described in the specific infrared absorber for convenience.

[0916] The following describes the particles described in Table 1.

[0917] • Techpolymer SSX-105: manufactured by SEKISUI PLASTICS CO., Ltd.

[0918] • Techpolymer SSX-104: manufactured by SEKISUI PLASTICS CO., Ltd.

[0919] • Techpolymer SSX-102: manufactured by SEKISUI PLASTICS CO., Ltd.

[0920] • Techpolymer SSX-101: manufactured by SEKISUI PLASTICS CO., Ltd.

[0921] • ART PEARL J-6PE: manufactured by Negami Chemical Industrial co., ltd.

[0922] • ART PEARL J-7PS: manufactured by Negami Chemical Industrial co., ltd.

[0923] <Forced Time Condition>

[0924] To evaluate the stability over time in the environment for storing the printing plate, a sample over time was produced under the following forced conditions for each evaluation. The lithographic printing plate precursor was left to stand for 4 hours with the layer containing the specific infrared absorber on the side in contact with air under an environment where the temperature was 27°C, the relative humidity was 70%, and the ozone concentration was 75 ppb. (This corresponds to a case where it is left to stand for 12 months under a normal environment where the temperature is 25°C and the relative humidity is 50%.)

[0925] <Printing durability evaluation>

[0926] The lithographic printing plate precursors of Examples 1 to 36 and Comparative Examples 1 and 2 were exposed by Luxcel PLATE SETTER T-6000 III manufactured by Fujifilm Corporation with an infrared semiconductor laser under the conditions of an outer drum rotation speed of 1,000 rpm, a laser output of 70%, and a resolution of 2,400 dpi. The exposure image used a chart including a solid image, a 50% dot, and a non-image portion.

[0927] The lithographic printing plate precursors on which the image was exposed were installed in a web offset printing machine manufactured by TOKYO KIKAI SEISAKUSHO, LTD., and printing was performed on a newspaper paper at a speed of 100,000 sheets / hour using SOYBI KKST-S (red) manufactured by INKTEC CO., LTD. as a printing ink for newspapers and TOYO ALKY manufactured by TOYO INK CO., LTD. as a dampening solution. As the number of printed sheets increased, the image recording layer was gradually abraded, and thus the ink density on the printed matter decreased.

[0928] The number of printed sheets until the value obtained by measuring the dot area ratio of a frequency modulation screened 50% dot in the printed matter with a Gretag densitometer was reduced by 5% from the measured value at the 100th printed sheet was measured. The number of printed sheets at which the 50% dot area was reduced by 5% was judged as the end point of printing, and when the number of printed sheets at the end of printing of the sample A without time was set as (a) and the number of printed sheets at the end of printing of the sample B over time was set as (b), the relative printing durability of the sample B over time was calculated by the following equation. At this time, the relative printing durability of the sample A became 100.

[0929] Relative printing durability = (b) / (a) x 100

[0930] Further, the value obtained by subtracting the relative printing durability of the sample B over time from the relative printing durability of the sample A was recorded as the Δ printing durability reduction value. If the Δ printing durability reduction value was 15 or less, the printing durability was excellent.

[0931] The obtained results are recorded in Table 1.

[0932] Decomposition rate of specific infrared absorber over time

[0933] The decomposition rate of the above infrared absorber was measured by the following method.

[0934] The above non-time-elapsed lithographic printing plate precursor A and the time-elapsed sample B were cut to have a size of 60 cm 2 × 60 cm, and extracted with 5 mL of acetonitrile in an ultrasonic bath for 30 minutes. The obtained extracts A, B were subjected to HPLC analysis through a 0.20 mm filter. The peak area of the specific infrared absorber of the extracts A and B obtained by HPLC analysis (peak area of non-time-elapsed specific infrared absorber (A) and peak area of specific infrared absorber over time (B)) were substituted into the following formula 1 to obtain the decomposition rate (C) of the specific infrared absorber.

[0935] Formula 1: (C) = 100 - [(B) / (A) x 100]

[0936] The various conditions at the time of HPLC analysis were as follows.

[0937] • Apparatus: Alliance 2695, Waters Corporation

[0938] • Column: Mightysil RP-18 GP 250 mm x φ 4.6 mm (5 μm), KANTO CHEMICAL CO., INC.

[0939] • Column temperature: 40°C

[0940] • Eluent: MeOH (containing 0.1 mass% acetic acid + 0.1 mass% triethylamine), H2O (containing 0.1 mass% acetic acid + 0.1 mass% triethylamine)

[0941] • Gradient: = 30 / 70 (0 min) - 100 / 0 (28 min) - 100 / 0 (40 min) - 30 / 70 (40.1 min) equalization

[0942] • Flow rate: 1.0 mL / min

[0943] • Injection volume: 10 mL

[0944] • UV detector: PDA 2998, Waters Corporation

[0945] The results obtained are described in Table 1.

[0946] <Plate Mounting Property (Mounting Property)>

[0947] A laminate in which 100 lithographic printing plate precursors were integrated in the same direction without using a backing paper was mounted on a CTP plate making machine "AMZI setter" manufactured by NEC ENGINEERING, LTD., and the operation of taking out the plates one by one from the uppermost part of the laminate was continuously performed 100 times. The plate separation property at this time was evaluated according to the following standard. The evaluation was performed as a sensory evaluation of 1 to 5, and 3 or more was the practical use level, and 2 or less was the level that could not be practically used.

[0948] 5: The phenomenon that the next plate was not lifted up when the plate was lifted up was 100%.

[0949] 4: The phenomenon that the next plate was lifted up when the plate was lifted up, and did not immediately fall off was 1% or less of the whole.

[0950] 3: The phenomenon that the next plate was lifted up when the plate was lifted up, and did not peel off by the first separation action was 1% or less of the whole.

[0951] 2: The phenomenon that the next plate was lifted up when the plate was lifted up, and did not peel off by the first separation action was more than 1% and 5% or less of the whole.

[0952] 1: The phenomenon that the next plate was lifted up when the plate was lifted up, and did not peel off by the first separation action was more than 5% of the whole.

[0953] The results obtained are described in Table 1.

[0954] Also, with respect to the lithographic printing plate precursor, the edge contamination prevention property was evaluated in the following manner.

[0955] <Trimming of Lithographic Printing Plate Precursor>

[0956] With respect to the lithographic printing plate precursors of Examples 1 to 36, the plate mounting property was evaluated using a CTP plate making machine "AMZI setter" manufactured by NEC ENGINEERING, LTD. Figure 4 The rotating blade shown adjusts the gap, engagement amount, and blade tip angle between the upper and lower cutting blades to perform cutting, resulting in a collapsed edge shape at the end.

[0957] The collapse amount X and collapse width Y in the collapse shape are recorded in Table 1.

[0958] <Formation of Edge Layer 1>

[0959] An edge layer 1 is formed by coating composition 1 under the following coating conditions 1.

[0960] (Coating Condition 1)

[0961] pass Figure 7 The coating method shown was used for coating. Regarding the printing bar, the bar was positioned perpendicular to the original lithographic printing plate (θ = 0°) and coating was performed. Coating was carried out through the following steps.

[0962] [1] 1 cm of solution was evenly added to the 10th bar. 3 The HN-GV is manufactured by FUJIFILM Global GraphicSystems Co., Ltd.

[0963] [2] The bar is moved at 20 mm / s along the side of the lithographic printing plate. At this time, the bar is set perpendicular to the lithographic printing plate (θ = 0°).

[0964] [3] The product was dried by blowing air at 80°C and 6 m / s for 30 seconds.

[0965] [4] It can coat only the sides of the original lithographic printing plate. In this case, the coating amount of composition 1 is 120 mg / m². 2 .

[0966] [5] The deviation Z of the coating width from the end of the original lithographic printing plate is Z = 0.1 mm.

[0967] Composition 1 contains the following ingredients.

[0968]

[0969] *1: Etherified starch (Nippon Starch Chemical Co., Ltd.)

[0970] *2: Cocamidopropyl Betaine (NOF Corporation)

[0971] *3: Disinfectant or bactericide (Daiwa Chemical Industries Corporation)

[0972] The above deviation Z is calculated according to

[0186] to

[0187] of Japanese Patent No. 6628949.

[0973] <Formation of the edge layer 2>

[0974] The edge layer 2 was formed in the same manner as the edge layer 1 except that the ink repellent (1) was used instead of the composition 1 in the coating condition 1.

[0975] • Ink repellent (1) HN-G5 (manufactured by Fujifilm Corporation)

[0976] The lithographic printing plate precursor having a deckle shape at the end, the edge layer were combined as in Table 1, whereby a lithographic printing plate precursor for measurement of edge contamination prevention over time was produced.

[0977] <Edge contamination prevention, over time>

[0978] The obtained lithographic printing plate precursor was subjected to time-dependent treatment to obtain sample B. The sample B was exposed by Fujifilm Corporation manufactured Luxcel PLATESETTER T-6000III equipped with infrared semiconductor laser under the conditions of outer drum rotation speed 1,000 rpm, laser output 70%, resolution 2,400 dpi. The exposure image used a figure including a solid image, 50% dot, non-image portion.

[0979] The lithographic printing plate precursor subjected to image exposure was installed in a web offset printing machine manufactured by TOKYO KIKAI SEISAKUSHO, LTD., and printing was performed at a speed of 100,000 sheets / hour on a newspaper paper using SOYBI KKST-S (red) manufactured by INKTEC CO., LTD. as a printing ink for newspapers and TOYO ALKY manufactured by TOYO INK CO., LTD. as a dampening solution. The first 1,000 printed matters were sampled at a water level to eliminate the dirty plate to 1.1 times the water level, and the degree of linear contamination caused from the end of the lithographic printing plate precursor was evaluated according to the following standards. The results are described as edge contamination prevention, not over time, in Table 1.

[0980] 5: Completely not contaminated

[0981] 4: Intermediate level between 5 and 3

[0982] 3: Slightly contaminated, but allowable

[0983] 2: intermediate level of 3 and 1 (permissible level)

[0984] 1: obviously contaminated and non-permissible level

[0985] The obtained results are described in Table 1.

[0986] From the results described in Table 1, it is known that the printing durability over time of the planographic printing plate precursor having at least one layer containing the specific infrared absorber constituting the laminate according to the present application is excellent, and the setting of the planographic printing plate precursor by the plate setter is excellent.

[0987] Further, it is known that the printing durability of the above planographic printing plate precursor is excellent by suppressing the decomposition rate of the specific infrared absorber over time.

[0988] In contrast, the printing durability over time of the planographic printing plate precursor of Comparative Example 1 containing an infrared absorber other than the specific infrared absorber is poor. Further, it is known that the setting of the laminate of Comparative Example 2 in which the arithmetic mean height Sa of the outermost layer surface of the planographic printing plate precursor is outside the range of the present application is poor.

[0989] In addition, it is known that the edge contamination over time is excellent by using the planographic printing plate precursor having a prescribed edge collapse shape.

[0990] Industrial applicability

[0991] According to the present application, it is possible to provide a laminate of a negative planographic printing plate precursor in which the printing durability over time is excellent and the setting is excellent, and a method for producing a negative planographic printing plate.

[0992] The present application has been described in detail and with reference to specific embodiments, but it is apparent to one skilled in the art that various changes or modifications can be made without departing from the spirit and scope of the present application.

[0993] In addition, this application is based on Japanese Patent Application (Japanese Patent Application No. 2020-218007) filed on December 25, 2020, and the content thereof is incorporated herein by reference.

[0994] Explanation of symbols

[0995] 1 - lithographic printing plate precursor, 1a - image recording layer surface, 1b - support surface, 1c - end surface, 2 - deckle, 10 - cutting blade, 10a - upper cutting blade, 10b - upper cutting blade, 11 - rotation shaft, 20 - cutting blade, 20a - lower cutting blade, 20b - lower cutting blade, 21 - rotation shaft, 30 - lithographic printing plate precursor, 31 - aluminum plate, 32, 34 - cylinder brush, 33 - polishing slurry, 35, 36, 37, 38 - support roll, 50 - main electrolytic cell, 51 - alternating current power supply, 52 - radial drum roll, 53a, 53b - main electrode, 54 - electrolyte supply port, 55 - electrolyte, 56 - slit, 57 - electrolyte passage, 58 - auxiliary anode, 60 - auxiliary anode groove, 410 - anodizing treatment device, 412 - power supply groove, 414 - electrolytic treatment groove, 416 - aluminum plate, 418, 426 - electrolyte, 420 - power supply electrode, 422, 428 - roll, 424 - nip roll, 430 - electrolytic electrode, 432 - groove wall, 434 - direct current power supply, B - boundary of image recording layer surface and support, W - aluminum plate, X - deckle amount, Y - deckle width, 100a - lithographic printing plate precursor, 120 - end surface, 122 - outermost surface on one side of a specific structure layer from the support as a reference, 138 - wire bar, θ - angle.

Claims

1. A laminate which is a laminate of a negative type lithographic printing plate precursor having at least one layer containing an infrared absorber having a HOMO of -5.47 eV or less on a hydrophilic support, an arithmetic mean height Sa of the outermost layer surface of at least one of the side of the at least one layer containing the infrared absorber on the support and the side opposite thereto is 0.3 μm or more and 20 μm or less.

2. The laminate according to claim 1, wherein the infrared absorber is a compound represented by the following formula (1), R1and R2each independently represent a hydrogen atom or an alkyl group, R1and R2are optionally linked to each other to form a ring, R3to R6each independently represent a hydrogen atom or an alkyl group, R7and R8each independently represent an alkyl group or an aryl group, Y1and Y2each independently represent an oxygen atom, a sulfur atom, -NR0-, or a dialkyl methylene group, R0represents a hydrogen atom, an alkyl group, or an aryl group, Ar1and Ar2each independently represent a group forming a benzene ring or a naphthalene ring optionally having a group represented by the following formula 2, A1represents -NR9R 10 , -X1-X 11 -L1or a group represented by the following formula 2, R9and R 10 each independently represents an alkyl group, an aryl group, an alkoxycarbonyl group, an arylsulfonyl group or a trihaloalkylsulfonyl group, X1represents an oxygen atom or a sulfur atom, X 11 represents a single bond or an alkylene group, L1represents a hydrocarbon group, a heteroaryl group, or a group which is cleaved from the bond of X1by heat or infrared exposure, Za represents a counter ion for neutralizing a charge, - X Formula 2 X represents a halogen atom, -C(=0)-X2-R 11 , -C(=0)-NR 12 R 13 , -0-C(=0)-R 14 , -CN, -SO2NR 15 R 16 or perfluoroalkyl, X2represents a single bond or an oxygen atom, R 11 represents a hydrogen atom, an alkyl group or an aryl group, R 14 represents an alkyl group or an aryl group, R 12 , R 13 , R 15 and R 16 each independently represent a hydrogen atom, an alkyl group or an aryl group.

3. The laminate according to claim 2, wherein A1 in the formula (1) is -NR 17 R 18 or -S-X 12 R 19 in the formula (1) is -NR R 17 and R 18 each independently represents aryl, R 19 represents hydrocarbyl or heteroaryl, X 12 represents a single bond or alkylene.

4. A laminate of the formula 2 wherein X is a fluorine atom, a chlorine atom, a bromine atom, or -C(=0)OR 20 of claim 2, wherein R 20 represents a hydrogen atom, an alkyl group or an aryl group.

5. The laminate according to claim 1 or 2, wherein the lithographic printing plate precursor has an image recording layer.

6. The laminate according to claim 5, wherein the at least one layer containing the infrared absorber is the image recording layer.

7. The laminate according to claim 5, wherein the image recording layer contains a polymerization initiator, a polymerizable compound, and a high molecular compound.

8. The laminate according to claim 7, wherein the high molecular compound is a high molecular compound containing at least one of a structural unit derived from a styrene compound and a structural unit derived from an acrylonitrile compound.

9. The laminate according to claim 8, wherein in the high molecular compound containing the structural unit derived from a styrene compound and the structural unit derived from an acrylonitrile compound, the composition ratio of the structural unit derived from a styrene compound to the structural unit derived from an acrylonitrile compound is 4: 1 to 1:

4.

10. The laminate according to any one of claims 7 to 9, wherein the high molecular compound is a polymer particle.

11. The laminate according to claim 7, wherein the high molecular compound contains at least a polyvinyl butyl resin.

12. The laminate according to claim 5, wherein the image recording layer contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

13. The laminate according to claim 5, wherein the image recording layer contains at least two kinds of particles having an average particle diameter of 0.5 μm or more and 20 μm or less and different average particle diameters.

14. The laminate according to claim 5, wherein the lithographic printing plate precursor has a protective layer on the image recording layer.

15. The laminate according to claim 14, wherein the at least one layer containing the infrared absorber is the protective layer.

16. The laminate according to claim 14 or 15, wherein the protective layer contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

17. The laminate according to claim 5, wherein the outermost layer on the side opposite to the side of the at least one layer containing the infrared absorber on the support contains at least one kind of particles having an average particle diameter of 0.5 μm or more and 20 μm or less.

18. The laminate according to claim 5, wherein the support is an aluminum support having an anodized film, The average diameter of the micropores on the surface of the anodic oxide film of the support is 10 nm to 100 nm, and the L-shaped diameter of the surface of the anodic oxide film containing at least one layer of the infrared absorber is... * a * b * Lightness (L) in the color system * The value is 70-100.

19. The laminate according to claim 5, wherein The support is an aluminum support having an anodized film, The micropores in the anodized film of the support are composed of large-diameter pores extending from the surface of the anodized film to a position at a depth of 10 nm to 1000 nm and small-diameter pores communicating with the bottoms of the large-diameter pores and extending from the communicating positions to positions at a depth of 20 nm to 2000 nm, the average diameter of the large-diameter pores at the surface of the anodized film being 15 nm to 100 nm, and the average diameter of the small-diameter pores at the communicating positions being 13 nm or less.

20. The laminate according to claim 5, wherein The support is an aluminum support having an anodized film, The micropores in the anodized film of the support are composed of small-diameter pores extending from the surface of the anodized film to a position at a depth of 10 nm to 1000 nm and large-diameter pores communicating with the bottoms of the small-diameter pores and extending from the communicating positions to positions at a depth of 20 nm to 2000 nm, the average diameter of the small-diameter pores at the surface of the anodized film being 35 nm or less, and the average diameter of the large-diameter pores being 40 nm to 300 nm.

21. The laminate according to claim 5, wherein The laminate is a laminate in which a plurality of the lithographic printing plate precursors are directly overlapped without interposition of a backing paper.

22. The laminate according to claim 5, wherein The end portion of the lithographic printing plate precursor has a shape of a collapsed edge having a collapsed edge amount X of 25 μm to 150 μm and a collapsed edge width Y of 70 μm to 300 μm.

23. The laminate according to claim 22, wherein A portion or all of the side surfaces of the opposite two edges of the lithographic printing plate precursor have a repelling agent.

24. A method for producing a negative-type lithographic printing plate, comprising the steps of: removing the lithographic printing plate precursor from the laminate according to any one of claims 5 to 23; image-exposing the lithographic printing plate precursor; and supplying at least one of a printing ink and a dampening solution and removing the unexposed portion of the image-recording layer of the lithographic printing plate precursor.

Images