JP2010120387A - Method for manufacturing lithographic printing plate and manufacturing set of lithographic printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a lithographic printing plate, capable of manufacturing the printing plate which has good transferability of an ink layer, and shows excellent adhesiveness of the ink layer and excellent plate wear resistance even when an ink ribbon having a thin ink layer is used. <P>SOLUTION: In the method for manufacturing the lithographic printing plate by transferring the ink layer of a thermofusible transfer recording medium to the image acceptance layer of the lithographic printing plate in a predetermined pattern, the ink layer as the thermofusible transfer recording medium is not more than 4 μm in thickness, and the image acceptance layer as the lithographic printing plate has an arithmetical average surface roughness Ra of not less than 0.15 μm and a ten point average roughness Rz of 1.00 to 3.00 μm according to the surface roughness regulation (JIS-B0601-1994). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  In the present invention, a pattern is transferred to a material for producing a lithographic printing plate (hereinafter also referred to as a printing plate) by a hot melt transfer recording method using a hot melt transfer recording medium (ink ribbon). The present invention relates to a method for producing a lithographic printing plate and a lithographic printing plate production set.

  In recent years, a plate making method has been proposed in which an image signal is not directly outputted from a computer to a photographic paper or a lith film, but is directly made by a digital output machine using a thermal head or an infrared semiconductor laser. As one of such direct plate making methods, a plate making method by a hot melt transfer recording method using a hot melt transfer recording medium (ink ribbon) is known (Patent Document 1, etc.).

  In the case of thermal melt transfer using an ink ribbon, if the transferability and fixability of the ink layer are not sufficient, printing durability such as white spots in solid image areas and dropouts of fine lines and small dots when used for platemaking and printing. As a lithographic printing plate material, it is desirable that the ink layer of the ink ribbon has good transferability and fixability. However, in general, the surface of the lithographic printing plate material is provided with a certain degree of irregularities in order to provide water retention, and such irregularities may cause a decrease in transferability of the ink layer of the ink ribbon. . In addition, when a material (hereinafter referred to as a non-etch type material) in which the surface of a lithographic printing plate material is hydrophilized in advance and does not require desensitization after plate making is used, the ink layer of the ink ribbon is used. The fixing property was inferior, and the above-described deterioration in printing performance was a problem.

  On the other hand, in the hot melt transfer recording method, a thin ink layer is used as an ink ribbon in order to obtain high resolution printing, and a plate making method using the hot melt transfer recording method is used. However, if an ink ribbon having such a thin ink layer is used, a high-resolution printed matter can be obtained.

  However, when an ink ribbon having a very thin ink layer is used as described above and transferred to the surface of a lithographic printing plate material having a concavo-convex surface as described above, the convex portion protrudes from the ink layer, Decreased transferability, such as white spots in the solid image portion of the printed matter, or convex portions in the non-image portion scratching the surface of the ink layer and causing smudges on the printed matter corresponding to the convex portions in the non-image portion This causes a problem that a good printed image cannot be obtained.

  This problem particularly in the image area is particularly problematic in a non-etch type material using a thermosetting water-soluble resin as a binder of the image receiving layer. In thermoplastic materials, unevenness is smoothed to some extent by the heat and pressure of the thermal head during ink layer transfer, whereas in thermosetting water-soluble resins, unevenness is smoothed by heat and pressure. This is thought to be because there is little conversion.

Japanese Patent Laid-Open No. 10-16420

  Therefore, the present invention is to produce a printing plate having good ink layer transferability, excellent ink layer fixing properties, and excellent printing durability even when an ink ribbon having a thin ink layer is used. An object of the present invention is to provide a method for producing a lithographic printing plate capable of producing a lithographic printing plate and a lithographic printing plate production set used for the method. Further, the present invention provides a method for preparing a lithographic printing plate excellent in water retention, not requiring desensitization after plate making and having excellent fixability of an ink ribbon, and a lithographic printing plate preparation set used therefor The purpose is to provide.

  In order to achieve the above-mentioned object, the present inventors have conducted intensive research on the surface shape of a lithographic printing plate material used in preparing a lithographic printing plate. As a result, the water retention is generally measured using a surface roughness scale. There is a correlation with a certain arithmetic average roughness Ra, and good water retention can be obtained within a predetermined arithmetic average roughness Ra depending on the material constituting the image receiving layer. The arithmetic average roughness Ra does not necessarily reflect the quality, and there is a correlation with the ten-point average roughness Rz, and by making the ten-point average roughness Rz within a predetermined range, good transferability, The present inventors have found that fixability can be obtained and water retention can be ensured, and the present invention has been achieved.

  That is, according to the present invention, in the method for producing a lithographic printing plate by transferring the ink layer of the hot-melt transfer recording medium to the image receiving layer of the lithographic printing plate material in a predetermined pattern, the hot-melt transfer recording medium, An ink layer having a thickness of 4 μm or less is used, and as the lithographic printing plate material, the surface roughness (JIS-B0601-1994) of the image receiving layer is an arithmetic average roughness Ra of 0.15 μm or more and A method for preparing a lithographic printing plate is provided, which uses a ten-point average roughness Rz of 1.00 to 3.00 μm.

  Further, in the above lithographic printing plate preparation method, the thickness of the ink layer is 0.5 μm or more. In the lithographic printing plate preparation method, the image receiving layer contains a hydrophilic polymer binder and a roughening agent having an average particle size of 1.5 to 2.5 μm. In the lithographic printing plate preparation method, the hydrophilic polymer binder is a crosslinked hydrophilic polymer compound. In the method for preparing a lithographic printing plate, the hydrophilic polymer binder contains fully saponified polyvinyl alcohol having a degree of polymerization of less than 1000 obtained by crosslinking a tetraalkoxysilane hydrolysis reaction product as a crosslinking agent.

  Furthermore, according to the present invention, in the lithographic printing plate preparation set used for preparing the lithographic printing plate by transferring the ink layer of the hot melt transfer recording medium to the image receiving layer of the lithographic printing plate material in a predetermined pattern, The hot-melt transfer recording medium has a thickness of the ink layer of 4 μm or less, and the lithographic printing plate material has a surface roughness (JIS-B0601-1994) of the image receiving layer of arithmetic average roughness Ra. A lithographic printing plate preparation set is provided which is 0.15 μm or more and has a ten-point average roughness Rz of 1.00 to 3.00 μm.

  In the lithographic printing plate preparation set, the ink layer has a thickness of 0.5 μm or more. In the lithographic printing plate preparation set, the image receiving layer contains a hydrophilic polymer binder and a roughening agent having an average particle size of 1.5 to 2.5 μm. In the lithographic printing plate preparation set, the hydrophilic polymer binder is a crosslinked hydrophilic polymer compound. In the lithographic printing plate preparation set, the hydrophilic polymer binder contains fully saponified polyvinyl alcohol having a degree of polymerization of less than 1000 obtained by crosslinking a tetraalkoxysilane hydrolysis reaction product as a crosslinking agent.

  In the present invention, when preparing a lithographic printing plate, the surface of the surface is obtained by using a lithographic printing plate material provided with an image receiving layer having a surface roughness (especially, ten-point average roughness Rz) in a specific range. A lithographic printing plate having excellent water resistance and excellent transferability and fixability of a hot-melt transfer recording medium (ink ribbon) having a thin ink layer can be obtained. In particular, since it has excellent transferability with respect to an ink ribbon having a thin ink layer, a lithographic printing plate that gives a printed image with high resolution can be obtained.

  In the present invention, the surface roughness of the image-receiving layer of the lithographic printing plate material used for preparing the lithographic printing plate is in a specific range, so that it has excellent water retention in the non-image area, and heat melt transfer recording. When a printing plate is manufactured by the method, the transferability and fixability of a hot-melt transfer recording medium with a thin ink layer is excellent, so that a printing plate with printing durability and high-quality printing can be obtained. Can do.

The lithographic printing plate production method of the present invention and the lithographic printing plate production set used therefor will be described in detail below.
The lithographic printing plate material used in the present invention has a structure comprising an image-receiving layer capable of hot-melt transfer recording using an ink ribbon on a support.

  As the support, a plastic film made of a resin such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, or polyethylene terephthalate, water-resistant paper laminated with the plastic film on the surface, or water-resistant paper coated with the resin on the surface are used. be able to.

  In particular, a polyethylene terephthalate film is preferable in terms of excellent mechanical strength, dimensional stability, chemical resistance, and water resistance. Moreover, in order to give an optical shielding effect, a film formed by mixing a concealing pigment such as carbon black or titanium oxide may be used. The thickness is not particularly limited, but a thickness of 50 μm to 300 μm is usually used.

  The support may be subjected to plasma treatment, corona discharge treatment, and deep ultraviolet irradiation treatment in order to improve adhesion to the image receiving layer. In addition, an undercoat layer may be provided as an easy adhesion process for the undercoat between the image receiving layer.

  The undercoat layer is preferably made of a resin having good adhesion to both the support and the resin constituting the image receiving layer. Accordingly, the resin constituting the undercoat layer varies depending on the support used and the resin of the image receiving layer. For example, vinyl acetate, vinyl chloride, styrene, butadiene, acrylic ester, methacrylic ester, ethylene, acrylonitrile, and other heavy resins are used. Water-insoluble polymers such as polymers or copolymers, polyester resins, polyurethane resins, alkyd resins, and epoxy resins, water-soluble polymers such as polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, casein, gelatin, and water-soluble polyurethane These can be used alone or in combination of two or more.

  The undercoat layer is formed by applying a coating solution containing such a resin on a support. The thickness is not particularly limited, but is usually 0.5 μm to 10 μm after drying.

  In the undercoat layer, additives such as a conductive agent, a colorant, a surfactant, and a crosslinking agent can be added as necessary.

  The image receiving layer has an arithmetic average roughness Ra of 0.15 μm or more, preferably 0.25 μm or more, and a ten-point average roughness Rz of 1.00 to 3.00 μm, preferably 1 .50 to 2.50 μm.

  The arithmetic average roughness Ra is a value obtained by integrating the absolute values of the elevations of the peaks and valleys of the roughness curve of the evaluation length and dividing it by the evaluation length to obtain a uniform elevation. Rz is a roughness curve with an evaluation length N times the sampling length equal to the cut-off value, and is divided into N equal parts, and the average elevation of the peak from the first to the fifth in each section And the arithmetic mean value of N Rz's when the average elevation interval Rz 'of the valley bottom with the depth from the first place to the fifth place is obtained.

  The surface roughness of such an image receiving layer determines the transferability, fixing ability, and dampening water holding power (water retention) of the ink layer of the ink ribbon, and the arithmetic average roughness Ra is 0. If the thickness is less than 15 μm, sufficient water retention cannot be obtained when a printing plate is formed, and background staining occurs.

  Further, when the ten-point average roughness Rz exceeds 3.00 μm, good ink layer transferability cannot be obtained. As a result, white spots or the like occur in the solid image portion, and background smudges occur in the non-image portion due to the rubbing of the ink ribbon. The reason why the surface roughness of the image receiving layer is limited by the ten-point average roughness Rz is that only the arithmetic average roughness Ra is set to a predetermined value includes a mountain (convex portion) whose elevation is considerably higher than the Ra value. In some cases, however, the integrated area may be a small value. In this case, when the ink layer is transferred to such a crest (convex portion), the crest (convex portion) protrudes from the ink layer. Is not transferred. On the other hand, the 10-point average roughness Rz does not include a mountain whose elevation is extremely higher than the Rz value. By setting this value within an appropriate range, a good transfer of the ink layer of the ink ribbon can be achieved. Can be secured.

  However, if the ten-point average roughness Rz is less than 1.00 μm, the fixability of the ink layer is inferior and sufficient printing durability cannot be obtained.

  The image receiving layer having such a surface shape includes a hydrophilic polymer binder, inorganic fine particles for imparting water retention, and a roughening agent for imparting the predetermined surface roughness described above.

  Examples of the hydrophilic polymer binder include hydrophilic polymer binders such as polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl pyrrolidone, and methyl vinyl ether maleic anhydride copolymer. Further, in order to improve the water resistance and mechanical strength of the image receiving layer, it is desirable to use a known crosslinking agent such as melamine resin, epoxy resin, polyisocyanate, aldehyde compound, silane compound in combination. In particular, fully saponified polyvinyl alcohol having a degree of polymerization of less than 1000 obtained by crosslinking a tetraalkoxysilane hydrolysis reaction product as a crosslinking agent is preferred.

  In order to improve the water retention, water resistance, and mechanical strength of the image receiving layer, in addition to the hydrophilic polymer binder described above, vinyl chloride, vinyl acetate, acrylate ester, ethylene, Resin emulsions such as emulsions of homopolymers such as styrene and copolymer resins can be added.

  The inorganic fine particles are added to enhance the water retention of the image receiving layer by providing fine irregularities.

  As such inorganic fine particles, zinc oxide, calcium carbonate, barium sulfate, silica, titanium oxide, clay, kaolin, aluminum hydroxide, alumina and the like can be used. In particular, a combination of titanium oxide and colloidal silica and / or colloidal alumina is preferred.

  The inorganic fine particles having an average particle size of less than 1 μm, preferably less than 0.2 μm are used. By setting the average particle diameter to less than 1 μm, the surface area of the image receiving layer can be sufficiently increased, and the water retention ability with respect to the fountain solution can be improved without lowering the water resistance.

  In order to acquire the said effect, the addition amount of an inorganic fine particle becomes like this. Preferably it is 150 weight% or more with respect to binder resin, More preferably, you may be 300 weight% or more. However, if the amount of inorganic fine particles added is increased, the coating film becomes brittle and the printing durability is lowered. Therefore, the amount is preferably 1000% by weight or less, more preferably 900% by weight or less.

  As a roughening agent for making the image receiving layer have a predetermined surface roughness, inorganic fine particles such as calcium carbonate, barium sulfate, clay, silica, alumina, acrylic resin, epoxy resin, nylon resin, polyethylene resin, fluorine Resin, synthetic resin fine particles such as benzoguanamine resin, etc., among which silica, particularly amorphous silica is preferable, and the average particle size is 1.0 to 3.0 μm, preferably 1.5 to 2.5 μm. Use things. A narrow particle size distribution is preferred.

  If the average particle size exceeds 3.0 μm, or if the average particle size is small and the particles have a wide particle size distribution and a large particle size, the ten-point average roughness Rz exceeds 3.0 μm, which is good. Transferability of the ink layer cannot be obtained. When the average particle diameter is less than 1.0 μm, most of the particles are buried in the resin constituting the image receiving layer, and sufficient fixing property of the ink layer cannot be obtained.

  The addition amount of the surface roughening agent is 5 to 100 parts, preferably 10 to 60 parts, with respect to 100 parts of the binder resin constituting the image receiving layer.

  In addition to the binder resin, inorganic fine particles, and roughening agent described above, the image-receiving layer is added with additives such as a conductive agent, a colorant, and a surfactant as necessary within a range that does not impair the above-described performance. be able to.

  The lithographic printing plate material used in the present invention forms an image receiving layer directly on a support or after applying a coating liquid containing a resin constituting the undercoat layer and drying to form an undercoat layer. It can form by apply | coating and drying the coating liquid containing a material. When using polyvinyl alcohol that is crosslinked by a tetraalkoxysilane hydrolysis reaction product as the hydrophilic polymer binder of the image-receiving layer, a dispersion containing polyvinyl alcohol and inorganic fine particles in advance and using alcohol and water as a solvent is prepared. In addition, a tetraalkoxysilane hydrolysis reaction product and a surface roughening agent are added to and mixed with this to obtain an image receiving layer coating solution. By applying this coating solution on a support or an undercoat layer and drying, an image receiving layer using crosslinked polyvinyl alcohol as a hydrophilic polymer binder can be formed.

  The thickness of the image receiving layer is not particularly limited, but is preferably 1 to 10 μm, more preferably 3 to 7 μm. By setting the thickness to 1 μm or more, the water-retaining property of the image-receiving layer, the transferability of the ink layer, and the fixability can be imparted.

  The lithographic printing plate material used in the present invention may be provided with a layer for adding various functions necessary for the printing plate, such as an antistatic layer or an anti-curl layer, on the surface opposite to the image receiving layer of the support. Is possible.

  The printing plate material for lithographic printing used in the present invention comprises a printing plate by forming a lipophilic transfer image on a hydrophilic image-receiving layer by a hot melt transfer recording method using a hot melt transfer recording medium (ink ribbon). To do. The image portion becomes an ink receiving portion on which printing ink is repelled with water, and the non-image portion on which the transfer image is not formed becomes dampening water and becomes a hydrophilic portion that repels ink.

  The hot-melt transfer recording medium (ink ribbon) is obtained by providing a lipophilic ink layer having a thickness of 0.5 to 4 μm on a polyester film support having a thickness of 3 to 6 μm. The ink layer is made of paraffin wax, micro wax, polyethylene wax, carnauba wax, candeli wax, montan wax, lanolin wax and the like having a melting point of 60 to 120 ° C., polyester resin, acrylic resin, urethane resin, ethylene vinyl acetate Resins, amide resins, polyterpene resins and the like have a softening point of 60 to 200 ° C., coloring pigments such as carbon black, and dispersants.

The ink ribbon may be provided with an overcoat layer on the ink layer in order to improve the adhesive force between the image receiving layer of the present invention and the ink layer and improve the transferability of the ink layer.
The lithographic printing plate material used in the present invention has a surface roughness, in particular, a ten-point average roughness Rz, within a specific range, so that even when an ink ribbon having an ink layer thickness of about 1 μm is used, The ink layer is not pierced by the unevenness, and the hot-melt transfer ink layer can be reliably and firmly transferred and fixed along the unevenness. As a result, a printing plate having excellent printing durability and high resolution can be obtained.

  Examples of lithographic printing plate materials used in the present invention will be described below. In Examples, “%” and “parts” represent “parts by weight” unless otherwise specified.

[Example 1]
On the support made of a white polyester film having a thickness of 125 μm, an undercoat layer coating solution having the following composition was applied by a bar coating method to a dry film thickness of 5 μm to form an undercoat layer.

<Undercoat layer coating solution>
・ Polyester resin 10 parts (Elitel UE3201: Unitika)
・ Isocyanate prepolymer (solid content 60%) 2 parts (Takenate D110N: Takeda Pharmaceutical Company Limited)
・ Toluene 40 parts ・ Methyl ethyl ketone 40 parts

  Next, an image receiving layer dispersion A having the following composition is prepared. Further, an image receiving layer coating liquid B is prepared using the dispersion A, and this is applied onto the above-described undercoat layer, dried, and then dried. A 7 μm image-receiving layer was formed to obtain a lithographic printing plate material.

<Image receiving layer dispersion A>
・ Inorganic fine particles 30 parts (Titanium oxide: average particle size 0.12μm)
(FA55W: Furukawa Machine Metal)
・ Inorganic fine particles 3 parts (Colloidal silica: primary particle size 12nm)
(Aerosil 200: Nippon Aerosil Co., Ltd.)
・ 100 parts of polyvinyl alcohol (10% aqueous solution) (Gohsenol NL05: Nippon Synthetic Chemical Industry Co., Ltd.)
・ Isopropyl alcohol 40 parts ・ Distilled water 100 parts

<Image receiving layer coating solution B>
・ Image receiving layer dispersion A 100 parts ・ Roughening agent 1 part (Amorphous silica: average particle size 1.9 μm)
(Silysia 530: Fuji Silysia Chemical)
・ Tetraalkoxysilane hydrolysis reaction product
15 parts The tetraalkoxysilane hydrolysis reaction product is
・ Tetraethoxysilane (Reagent: Wako Pure Chemical Industries, Ltd.)
100 parts, 100 parts of ethanol, 200 parts of 0.1N aqueous hydrochloric acid solution were mixed and subjected to a hydrolysis reaction at room temperature for 24 hours.

[Comparative Example 1]
A lithographic printing plate material was obtained in the same manner as in Example 1 except that no roughening agent was added in the preparation of the image-receiving layer coating solution B in Example 1.

[Comparative Example 2]
A lithographic printing plate material was obtained in the same manner as in Example 1 except that the roughening agent was changed as follows in the preparation of the image-receiving layer coating solution B in Example 1.

<Image receiving layer coating solution B '>
・ Image receiving layer dispersion A 100 parts ・ Roughening agent 1 part (Silica: average particle size 3.0 μm)
(Silysia 730: Fuji Silysia Chemical)
・ Roughening agent 1 part (silica: average particle size 6.0μm)
(Silysia 770: Fuji Silysia Chemical)
・ Tetraalkoxysilane hydrolysis reaction product
15 copies

  Table 1 shows the surface roughness (arithmetic average roughness Ra, ten-point average roughness Rz) of the lithographic printing plate materials obtained in the examples and comparative examples.

[Transferability]
The lithographic printing plate materials of the examples and comparative examples are digital data using an ink ribbon hot melt transfer printer having a 600 DPI serial head using a hot melt transfer ink ribbon having a 1 μm ink layer thickness. A 18-point Mincho character, 85 line 10%, 30%, 50%, 70% flat screen image and black solid image were output to make a lithographic printing plate. After the lithographic printing plate was evaluated for the printer output image of (1) below, the lithographic printing plate was printed under the following printing conditions without desensitizing, and the following (2) solid print The evaluation of the transferability of the ink layer was performed by evaluating the white spots of the image area and (3) evaluating the background stain of the non-image area of the printed matter by rubbing the ribbon. The results are shown in Table 2.

Printing machine Heidelberg Quickmaster QM46-1
Printing speed 6000 sheets / hr
Paper Coated paper (OK top coat)
Ink TK High Echo Black M: Toyo Ink Manufacturing Co., Ltd. Dampening solution Astro Mark 3: Nikken Chemical Laboratory
50 times tap water dilution.

(1) Printer output image evaluation evaluation ○: Evaluation that no white spots are generated in the black solid image portion of the lithographic printing plate and black stains are not generated in the non-image portion due to rubbing of the ink layer ×: The black solid image portion of the lithographic printing plate has white spots, or the non-image portion has black stains due to the rubbing of the ink layer. (2) White spot evaluation evaluation of the solid image portion of the printed matter. : Evaluation of a black solid image portion with no white spots in the printed material ×: Evaluation of a white solid image portion in the black solid image portion of the printed material (3) Evaluation in which non-image areas are not stained due to rubbing of the ribbon Evaluation ×: Non-image areas of printed matter are stained due to rubbing of the ribbon

[Fixability]
The printed material produced in the above-described evaluation of transferability was observed for printing durability, and the fixability of the ink layer to the image receiving layer was evaluated. The results are shown in Table 2.
Evaluation ○: Even if the number of printed sheets exceeds 5000, evaluation is made that the 3 to 18 point Mincho characters, 85-line 10%, 30%, 50%, and 70% flat screen images are sufficiently resolved and reproduced × : 100th printed page with missing Mincho characters and part of flat screen image

[Water retention]
The printed material produced in the above-described evaluation of transferability was evaluated for water retention of the image-receiving layer by observing whether or not background staining was caused by insufficient water retention. The results are shown in Table 2.
Evaluation ○: For a printed matter with 100 sheets printed, no smudge due to lack of water retention in the non-image area. Evaluation x: For a printed matter with 100 sheets printed, background smudge due to lack of water retention in the non-image area. What is happening

  As can be seen from the results shown in Tables 1 and 2, in Comparative Example 1, since the arithmetic average roughness Ra and the ten-point average roughness Rz were both small, the transferability of the ink layer was good. Since the fixability is poor, there is no printing durability at all, and sufficient water retention cannot be obtained when a printing plate is formed.

  In Comparative Example 2, the arithmetic average roughness Ra was within the range, and thus the water retention was good, but the ten-point average roughness Rz was large, so that the convex portion protruded from the ink layer and became a black solid image portion. In addition to white spots, the convex portions of the non-image area rubbed the ink layer and caused stains on the printing plate, which caused white spots and background stains on the printed matter.

  On the other hand, the lithographic printing plate material of the example in which the arithmetic average roughness Ra and the ten-point average roughness Rz are in appropriate ranges have good transferability and fixing property of the ink layer, and when used as a printing plate. Excellent water retention.

Claims (10)

In a method for producing a lithographic printing plate by transferring an ink layer of a hot melt transfer recording medium to an image receiving layer of a lithographic printing plate material in a predetermined pattern,
As the hot-melt transfer recording medium, the ink layer having a thickness of 4 μm or less is used.
As the lithographic printing plate material, the image receiving layer has a surface roughness (JIS-B0601-1994) of arithmetic average roughness Ra of 0.15 μm or more and a ten-point average roughness Rz of 1.00 to 3.00 μm. A method for producing a lithographic printing plate, comprising using In the preparation method of the lithographic printing plate according to claim 1,
A method for preparing a lithographic printing plate, wherein the ink layer has a thickness of 0.5 μm or more. In the preparation method of the lithographic printing plate according to claim 1 or 2,
The method for preparing a lithographic printing plate, wherein the image receiving layer contains a hydrophilic polymer binder and a roughening agent having an average particle size of 1.5 to 2.5 μm. In the method for producing a lithographic printing plate according to claim 3,
The method for preparing a lithographic printing plate, wherein the hydrophilic polymer binder is a crosslinked hydrophilic polymer compound. In the preparation method of the lithographic printing plate according to claim 3 or 4,
The method for preparing a lithographic printing plate, wherein the hydrophilic polymer binder contains a fully saponified polyvinyl alcohol having a degree of polymerization of less than 1000 obtained by crosslinking a tetraalkoxysilane hydrolysis reaction product as a crosslinking agent. In the lithographic printing plate preparation set used for preparing the lithographic printing plate by transferring the ink layer of the hot melt transfer recording medium to the image receiving layer of the lithographic printing plate material in a predetermined pattern,
The hot melt transfer recording medium has a thickness of the ink layer of 4 μm or less,
The lithographic printing plate material has a surface roughness (JIS-B0601-1994) of the image receiving layer of not less than 0.15 μm in arithmetic average roughness Ra and 1.00 to 3.00 μm in ten-point average roughness Rz. A lithographic printing plate production set characterized by In the lithographic printing plate making set according to claim 6,
A lithographic printing plate preparation set, wherein the ink layer has a thickness of 0.5 μm or more. In the lithographic printing plate making set according to claim 6 or 7,
The lithographic printing plate preparation set, wherein the image receiving layer contains a hydrophilic polymer binder and a roughening agent having an average particle size of 1.5 to 2.5 μm. In the lithographic printing plate making set according to claim 8,
The lithographic printing plate preparation set, wherein the hydrophilic polymer binder is a crosslinked hydrophilic polymer compound. In the lithographic printing plate making set according to claim 8 or 9,
The lithographic printing plate preparation set, wherein the hydrophilic polymer binder contains a fully saponified polyvinyl alcohol having a degree of polymerization of less than 1000 obtained by crosslinking a tetraalkoxysilane hydrolysis reaction product as a crosslinking agent.