Silicone resin composition and plate surface correction fluid for waterless lithographic printing plate using the same

Abstract

To provide a silicone resin composition which has excellent curability without requiring an organotin compound.SOLUTION: The silicone resin composition contains (a) a silicone resin having two or more silanol groups, (b) a silane compound having an oxime group directly bonded to Si, and (c) a titanium compound having a structure represented by the following general formula (1). (In general formula (1), R1 and R2 each independently represent a hydrogen atom, a hydroxy group, a C1-8 alkyl group, a C1-8 alkoxy group or a C6-12 aryloxy group; R3 represents a hydrogen atom or a C1-8 alkyl group; m represents an integer of 1-3; and r represents an integer of 0-2.)SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a silicone resin composition, a plate surface correction fluid for a waterless lithographic printing plate comprising the same, a cured product of the silicone resin composition, and a waterless lithographic printing plate having the same. Regarding. [Background technology]

[0002] Waterless lithographic printing is a printing method in which a waterless lithographic printing plate has ink-receptive image areas and ink-repellent non-image areas made of silicone rubber or the like, which are located on approximately the same plane as the printing plate, and ink is applied only to the image areas, taking advantage of the difference in ink adhesion properties, and then the ink is transferred to the printed material. Because it does not require dampening water to exhibit ink repellency, it has attracted attention as a printing method that reduces the burden on the environment.

[0003] In waterless lithographic printing plates, defects such as scratches and pinholes may occur in ink-repellent non-image areas. Such defects reduce the ink repellency, allowing ink to adhere to the non-image areas, resulting in poor printing, and so it is necessary to correct the defects. In some cases, it is necessary to correct the ink-receptive image areas to ink-repellent non-image areas. As a method for correcting such non-image areas, a method for correcting a directly drawn waterless lithographic printing plate (see, for example, Patent Document 1) has been proposed, which comprises applying a silicone rubber solution to defective areas in the silicone rubber layer and / or image areas from which the silicone rubber layer has been removed, and curing the solution to form a thin silicone rubber film. Examples of surface correction fluids for waterless lithographic printing plates used in such correction methods include a surface correction fluid for a CTP lithographic printing plate that does not require dampening water, characterized by containing (a) a linear dimethylpolysiloxane having one or more hydroxyl groups at each end, (b) an acetoxysilane having two or more acetoxy groups, (c) a catalyst, and (d) an adhesion promoter (see, for example, Patent Document 2); and a surface correction fluid for a waterless lithographic printing plate, characterized by containing (a) an organopolysiloxane having one or more hydroxyl groups at each end, (b) a crosslinking agent, (c) a catalyst, (d) a colored pigment, and (e) a pigment dispersant (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2001-324820 A [Patent Document 2] JP 2005-257846 A [Patent Document 3] JP 2008-158264 A Summary of the Invention [Problem to be solved by the invention]

[0005] The plate surface correction fluids described in Patent Documents 2 and 3 use an organotin compound as a curing catalyst. Organotin compounds are considered to be a heavy burden on the environment and health, and plate surface correction fluids that do not use organotin compounds are in demand. However, in conventional plate surface correction fluids, when the organotin compound is replaced with another metal catalyst, there is a problem that the curing property becomes insufficient.

[0006] Therefore, an object of the present invention is to provide a silicone resin composition that has excellent curing properties without requiring an organotin compound. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention mainly has the following configuration. <1> A silicone resin composition comprising: (a) a silicone resin having two or more silanol groups; (b) a silane compound having an oxime group directly bonded to Si; and (c) a titanium compound having a structure represented by the following general formula (1):

[0008] [ka]

[0009] In the above general formula (1), R 1 and R2 R each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms. 3 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. m represents an integer of 1 to 3. r represents an integer of 0 to 2. <2> Further containing (d) silicone oil, <1> The silicone resin composition described above. <3> In the general formula (1), r is 0. <1> or <2> The silicone resin composition described above. <4> In the general formula (1), [ ] m the structure represented by the formula (I) is a (4-oxopent-2-en-2-yl)oxy group, a (4-alkoxy-4-oxobut-2-en-2-yl)oxy group having a total carbon number of 5 to 12, or a (4-aryloxy-4-oxobut-2-en-2-yl)oxy group having a total carbon number of 10 to 16, <1> ~ <3> 2. The silicone resin composition according to claim 1 . <5> The content of the (c) titanium compound having a structure represented by general formula (1) is 1.5 parts by mass to 35 parts by mass per 100 parts by mass of the (a) silicone resin having two or more silanol groups. <1> ~ <4> 2. The silicone resin composition according to claim 1 . <6> The (b) silane compound having an oxime group directly bonded to Si has a structure represented by the following general formula (2): <1> ~ <5> 2. The silicone resin composition according to claim 1 .

[0010] [ka]

[0011] In the above general formula (2), R 4 and R 5 R each independently represents an alkyl group having 1 to 8 carbon atoms. 6 represents an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 1 to 8 carbon atoms. n represents an integer of 1 to 4. <7> The content of the (b) silane compound having an oxime group directly bonded to Si is 2.5 parts by mass to 35 parts by mass relative to 100 parts by mass of the (a) silicone resin having two or more silanol groups. <1> ~ <6> 2. The silicone resin composition according to claim 1 . <8> <1> ~ <7> 2. A surface correction fluid for a waterless lithographic printing plate comprising the silicone resin composition according to any one of claims 1 to 11. <9> <1> ~ <7> 2. A cured product of the silicone resin composition according to claim 1. <10> On the substrate, an ink-receptive layer and <9> 2. A waterless lithographic printing plate having an ink repellent layer comprising the cured product according to claim 1. Effect of the Invention

[0012] According to the present invention, it is possible to provide a silicone resin composition that has excellent curability without requiring an organotin compound. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The silicone resin composition of the present invention contains (a) a silicone resin having two or more silanol groups (hereinafter may be abbreviated as "(a) silicone resin"), (b) a silane compound having an oxime group directly bonded to Si (hereinafter may be abbreviated as "(b) silane compound"), and (c) a titanium compound having a structure represented by the following general formula (1) (hereinafter may be abbreviated as "(c) titanium compound"):

[0014] [ka]

[0015] In the above general formula (1), R 1 and R 2 R each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms. 3 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. m represents an integer of 1 to 3. r represents an integer of 0 to 2.

[0016] As mentioned above, in the conventional silicone resin composition, when the organotin compound is replaced with another metal catalyst, there is a problem that the curing property becomes insufficient. In the present invention, by containing the (b) silane compound and the (c) titanium compound together with the (a) silicone resin, the (c) titanium compound induces or promotes the reaction of the oxime group directly bonded to the Si of the (b) silane compound with moisture in the air, that is, hydrolysis. The silanol group generated by hydrolysis condenses with the silanol group of the (a) silicone resin or the oxime group remaining in the (b) silane compound, or condenses with each other to form a crosslinked structure. Therefore, the silicone resin composition of the present invention has excellent curing properties and cures in a short time even at room temperature. Furthermore, the (c) titanium compound is a compound represented by the formula [ ] in the general formula (2). m Since the structure shown in the figure is strongly bonded or coordinated to titanium atoms, it can exist stably in the silicone resin composition and has excellent storage stability. In addition, Ti-OR capable of forming a metal-oxygen-metal bond, i.e., a metalloxane bond, 3 Since the titanium compound (c) has a silanol group, in the cured product, it condenses with the silanol group of the silicone resin (a) to form a crosslinked structure, and is incorporated and fixed in the silicone resin (a). Therefore, the titanium compound (c) itself also functions as a crosslinking agent, and can improve the curability of the silicone resin composition.

[0017] The silicone resin composition of the present invention has excellent curing properties and cures in a short time even at room temperature, and therefore can be suitably used, for example, as a plate surface correction fluid for a waterless lithographic printing plate described below, or as an ink repellent layer for a waterless lithographic printing plate precursor, which is a precursor prior to the formation of image areas / non-image areas on a waterless lithographic printing plate. In particular, when used as a plate surface correction fluid for a waterless lithographic printing plate, it also has excellent adhesion to an ink repellent layer using silicone rubber.

[0018] The (a) silicone resin preferably has a structure represented by the following general formula (3), and can improve the ink repellency of the cured product of the silicone resin composition. Therefore, when used in a plate surface correction fluid for a waterless lithographic printing plate or in the ink repellent layer of a waterless lithographic printing plate precursor, it can suppress the phenomenon known as "scumming," in which ink adheres to non-image areas.

[0019] [ka]

[0020] In the above general formula (2), T is a group represented by the following general formula (4): In the following general formula (4), * indicates the bonding position with Si.

[0021] [ka]

[0022] In the above general formula (3) and general formula (4), R 7 each independently represents a monovalent hydrocarbon group that does not contain a hydroxyl group or an aliphatic unsaturated bond, R 8 each independently represents a monovalent hydrocarbon group that does not contain an aliphatic unsaturated bond. Examples of monovalent hydrocarbon groups that do not contain an unsaturated bond include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, and heptyl; aryl groups such as phenyl, methylphenyl, dimethylphenyl, and naphthyl; and aralkyl groups such as benzyl and phenethyl. e represents an integer ranging from 0 to 4,000, f represents an integer ranging from 0 to 5, g represents an integer ranging from 0 to 2,000, and h represents an integer ranging from 0 to 4,000. However, any one of e, f, and g is an integer of 1 or more. When any one of e, f, and g is 2 or more, R in the e, f, and g repeating units is an integer ranging from 0 to 4,000. 8 may be the same or different. 7 When is a monovalent hydrocarbon group containing no unsaturated bonds, f is an integer of 2 or greater.

[0023] In the general formulas (3) and (4), R7 and R 8 Preferably, each of the groups is 50 mol % or more of the total. By having 50 mol % of the group being methyl, the ink repellency of the cured product of the silicone resin composition can be improved. Therefore, when used in a plate surface correction fluid for a waterless lithographic printing plate or in the ink repellent layer of a waterless lithographic printing plate precursor, background scumming can be suppressed.

[0024] The (a) silicone resin preferably has silanol groups at both ends of the main chain. That is, R 7 is preferably a hydroxyl group. By having silanol groups at both ends of the main chain, the curability of the silicone resin composition can be further improved.

[0025] (a) The silicone resin may contain two or more kinds.

[0026] The weight average molecular weight (Mw) of the (a) silicone resin is preferably 10,000 or more, more preferably 20,000 or more, from the viewpoint of further improving the ink repellency of the cured product of the silicone resin composition. On the other hand, the Mw of the (a) silicone resin is preferably 300,000 or less, more preferably 120,000 or less, from the viewpoint of further improving the curability of the silicone resin composition and the adhesion of the cured product of the silicone resin composition to the base. Here, the Mw of the (a) silicone resin can be measured by gel permeation chromatography (GPC) using polystyrene as a standard.

[0027] The (b) silane compound preferably has a structure represented by the following general formula (2): By having the structure represented by general formula (2), the reactivity in hydrolysis and condensation reactions is excellent, and therefore the curability of the silicone resin composition can be further improved.

[0028] [ka]

[0029] In the above general formula (2), R4 and R 5 R each independently represents an alkyl group having 1 to 8 carbon atoms. 6 represents an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 1 to 8 carbon atoms. n represents an integer of 1 to 4. When n is 2 or more, n R 4 and R 5 may be the same or different, and when n is 2 or less, there are 4-n R 6 may be the same or different.

[0030] Examples of the alkyl group having 1 to 8 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a s-butyl group, a t-butyl group, a pentyl group, a hexyl group, a cyclopentyl group, and a cyclohexyl group.

[0031] Examples of the alkenyl group having 1 to 8 carbon atoms include a vinyl group, a propenyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, and an octenyl group.

[0032] In the above general formula (2), n is preferably 3 from the viewpoint of improving the adhesion of the cured product of the silicone resin composition to the base, and n is preferably 4 from the viewpoint of increasing the hydrolysis rate and crosslink density to further improve the curability of the silicone resin composition.

[0033] Examples of the silane compound in which n is 3 in the above general formula (2) include methyl tris(methyl ethyl ketoxime)silane, methyl tris(methyl isobutyl ketoxime)silane, vinyl tris(methyl ethyl ketoxime)silane, and vinyl tris(methyl isobutyl ketoxime)silane. Among these, from the viewpoint of further improving the curing property, methyl tris(methyl ethyl ketoxime)silane and vinyl tris(methyl ethyl ketoxime)silane are preferred. Examples of the silane compound in which n is 4 in the general formula (2) include tetrakis(methyl ethyl ketoxime)silane and tetrakis(methyl isobutyl ketoxime)silane. Two or more of these may be contained.

[0034] The silicone resin composition of the present invention preferably contains a silane compound in which n is 3 in the above general formula (2) and a silane compound in which n is 4, which can further improve the curability of the silicone resin composition and the adhesion of the cured product of the silicone resin composition to the base. (b) In a total content of 100 parts by mass of the silane compounds, it is preferable to contain 10 parts by mass or more of a silane compound in which n is 4 in the general formula (2) and 90 parts by mass or less of a silane compound in which n is 3, which can further improve the curability of the silicone resin composition. On the other hand, it is preferable to contain 50 parts by mass or less of a silane compound in which n is 4 and 50 parts by mass or more of a silane compound in which n is 3, which can further improve the adhesion of the cured product of the silicone resin composition to the base.

[0035] The content of the (b) silane compound in the silicone resin composition of the present invention is preferably 2.5 parts by mass or more, more preferably 4.0 parts by mass or more, per 100 parts by mass of the (a) silicone resin, from the viewpoint of further improving the curability of the silicone resin composition and the adhesion of the cured product of the silicone resin composition to the substrate. On the other hand, the content of the (b) silane compound is preferably 35 parts by mass or less, more preferably 20 parts by mass or less, per 100 parts by mass of the (a) silicone resin, from the viewpoint of further improving the ink repellency of the cured product of the silicone resin composition.

[0036] The (c) titanium compound has a structure represented by the following general formula (1).

[0037] [ka]

[0038] In the above general formula (1), R 1 and R 2 R each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms. 3represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. m represents an integer of 1 to 3. r represents an integer of 0 to 2.

[0039] In general formula (1), R 3 is preferably an alkyl group having 2 to 5 carbon atoms. By making the alkyl group have 2 or more carbon atoms, the stability of the silicone resin composition can be improved. On the other hand, by making the alkyl group have 5 or less carbon atoms, the curability of the silicone resin composition can be further improved. Examples of the alkyl group having 2 to 5 carbon atoms include an ethyl group, a propyl group, a butyl group, and a pentyl group.

[0040] In the general formula (1), r is preferably 0. That is, [ ] in the general formula (1) m The structure represented in the brackets is preferably a group derived from a β-diketone or a β-ketoester. m Since the structure shown in the figure is strongly bonded or coordinated to the titanium atom, it can exist stably in the silicone resin composition. Therefore, it is possible to further promote the hydrolysis of the (b) silane compound and further improve the curability of the silicone resin composition.

[0041] In the general formula (1), [ ] m The structure represented by the formula (1) is more preferably a (4-oxopent-2-en-2-yl)oxy group, a (4-alkoxy-4-oxobut-2-en-2-yl)oxy group having a total carbon number of 5 to 12, or a (4-aryloxy-4-oxobut-2-en-2-yl)oxy group having a total carbon number of 10 to 16. By having these groups, the hydrolysis of the (b) silane compound can be further promoted, and the curability of the silicone resin composition can be further improved.

[0042] Examples of the (4-alkoxy-4-oxobut-2-en-2-yl)oxy group having a total carbon number of 5 to 12 include a (4-methoxy-4-oxobut-2-en-2-yl)oxy group, a (4-ethoxy-4-oxobut-2-en-2-yl)oxy group, a (4-propoxy-4-oxobut-2-en-2-yl)oxy group, a (4-butoxy-4-oxobut-2-en-2-yl)oxy group, a (4-pentoxy-4-oxobut-2-en-2-yl)oxy group, and a (4-hexoxy-4-oxobut-2-en-2-yl)oxy group. Examples of the (4-aryloxy-4-oxobut-2-en-2-yl)oxy group having a total carbon number of 10 to 16 include a (4-phenoxy-4-oxobut-2-en-2-yl)oxy group and a (4-naphthoxy-4-oxobut-2-en-2-yl)oxy group.

[0043] (c) Examples of titanium compounds in the case where m=1 in the general formula (1) include triethoxy((4-oxopent-2-en-2-yl)oxy)titanium, triethoxy((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, triethoxy((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium, triisopropoxy((4-oxopent-2-en-2-yl)oxy)titanium, triisopropoxy((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, triisopropoxy((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium, and triisopropoxy((4-ethoxy-4-oxobut-2-en-2-yl)oxy). oxy) titanium, tri-n-propoxy ((4-oxopent-2-en-2-yl)oxy) titanium, tri-n-propoxy ((4-methoxy-4-oxobut-2-en-2-yl)oxy) titanium, tri-n-propoxy ((4-ethoxy-4-oxobut-2-en-2-yl)oxy) titanium, tri-n-butoxy ((4-oxopent-2-en-2-yl)oxy) titanium, tri-n-butoxy ((4-methoxy-4-oxobut-2-en-2-yl)oxy) titanium, tri-n-butoxy ((4-ethoxy-4-oxobut-2-en-2-yl)oxy) titanium, and the like.

[0044] In the case of m=2, for example, diethoxybis((4-oxopent-2-en-2-yl)oxy)titanium, diethoxybis((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, diethoxybis((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium, diisopropoxybis((4-oxopent-2-en-2-yl)oxy)titanium, diisopropoxybis((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, diisopropoxybis((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium, di-n- Examples of the oxysilane include propoxybis((4-oxopent-2-en-2-yl)oxy)titanium, di-n-propoxybis((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, di-n-propoxybis((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium, di-n-butoxybis((4-oxopent-2-en-2-yl)oxy)titanium, di-n-butoxybis((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, and di-n-butoxybis((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium.

[0045] When m=3, for example, ethoxytris((4-oxopent-2-en-2-yl)oxy)titanium, ethoxytris((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, ethoxytris((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium, isopropoxytris((4-oxopent-2-en-2-yl)oxy)titanium, isopropoxytris((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, isopropoxytris((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium, n -propoxytris((4-oxopent-2-en-2-yl)oxy)titanium, n-propoxytris((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, n-propoxytris((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium, n-butoxytris((4-oxopent-2-en-2-yl)oxy)titanium, n-butoxytris((4-methoxy-4-oxobut-2-en-2-yl)oxy)titanium, and n-butoxytris((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium.

[0046] Two or more of these may be contained.

[0047] The content of the (c) titanium compound in the silicone resin composition of the present invention is preferably 1.5 parts by mass or more, more preferably 3.0 parts by mass or more, per 100 parts by mass of the (a) silicone resin, from the viewpoint of further improving the curability of the silicone resin composition and the adhesion of the cured product of the silicone resin composition to the substrate. On the other hand, the content of the (c) titanium compound is preferably 35 parts by mass or less, more preferably 25 parts by mass or less, per 100 parts by mass of the (a) silicone resin, from the viewpoint of further improving the ink repellency of the cured product of the silicone resin composition.

[0048] The silicone resin composition of the present invention preferably further contains (d) silicone oil. By containing (d) silicone oil, the ink repellency of the cured product of the silicone resin composition can be further improved. This is thought to be because, for example, in the plate surface correction fluid or ink repellent layer of a waterless lithographic printing plate, when the cured product of the silicone resin composition is pressurized during printing, the (d) silicone oil forms a thin film on the surface of the cured product, facilitating the release of the ink, and thus suppressing background scumming.

[0049] The silicone oil (d) in the present invention refers to a free polysiloxane component that is not involved in the crosslinking of the silicone resin composition. For example, dimethyl silicone oils such as terminal dimethyl polydimethyl siloxane, cyclic polydimethyl siloxane, terminal dimethyl-polydimethyl-polymethylphenyl siloxane copolymer, terminal dimethyl-polydimethyl-polydiphenyl siloxane copolymer, etc., alkyl-modified silicone oil, fluorine-modified silicone oil, polyether-modified silicone oil, alcohol-modified silicone oil, phenol-modified silicone oil, etc., in which various organic groups are introduced into a part of the methyl group in the molecule, can be mentioned. Two or more of these can be contained.

[0050] The weight average molecular weight (Mw) of the (d) silicone oil is preferably 500 or more, more preferably 1,000 or more, from the viewpoint of suppressing the volatilization of the silicone oil and further improving the ink repellency of the cured product of the silicone resin composition. On the other hand, the Mw of the (d) silicone oil is preferably 50,000 or less, more preferably 10,000 or less, from the viewpoint of improving the dispersibility in the silicone resin composition and further improving the curability of the silicone resin composition. Here, the Mw of the (d) silicone resin can be measured by GPC using polystyrene as a standard.

[0051] The content of the silicone oil (d) in the silicone resin composition of the present invention is preferably 3.0 parts by mass or more, more preferably 7.0 parts by mass or more, and even more preferably 15 parts by mass or more, based on 100 parts by mass of the silicone resin (a) from the viewpoint of further improving the ink repellency of the cured product. On the other hand, from the viewpoint of further improving the adhesion of the cured product of the silicone resin composition to the base, the content is preferably 30 parts by mass or less, and more preferably 25 parts by mass or less.

[0052] The surface tension of (d) silicone oil at 25° C. is preferably 15 mN / m or more from the viewpoint of enhancing the affinity with the above-mentioned components (a) to (c), while the surface tension of (d) silicone oil at 25° C. is preferably 30 mN / m or less from the viewpoint of further improving the ink repellency of the cured product of the silicone resin composition.

[0053] The silicone resin composition of the present invention may contain a solvent, which can improve the coating property and discharge property. Examples of the solvent include aliphatic or aromatic hydrocarbons, halogenated hydrocarbons, and linear or cyclic ether compounds. Two or more of these may be contained. Among these, aliphatic hydrocarbons are preferred from the viewpoint of the solubility of the (a) silicone resin. The boiling point is preferably 80°C or more and 150°C or less. Examples of such solvents include linear or branched aliphatic hydrocarbons having 6 to 9 carbon atoms, and alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, ethylcyclohexane, dimethylcyclohexane, and trimethylcyclohexane. Two or more of these solvents may be contained, and commercially available solvents in which these solvents are mixed in advance, such as those typified below, may be used.

[0054] Examples of mixtures of branched aliphatic hydrocarbons include Marukasol 8 (manufactured by Maruzen Petrochemical Co., Ltd.), "Isopar (registered trademark)" C, "Isopar (registered trademark)" E (all manufactured by ExxonMobil Chemical Co.), IP Solvent 1016 (manufactured by Idemitsu Kosan Co., Ltd.), and "Isosol (registered trademark)" 200 (manufactured by JX Nippon Oil & Energy Corporation).

[0055] Examples of mixtures of alicyclic hydrocarbons include "Exxor (registered trademark)" DSP80 / 100, "Exxor" DSP100 / 140, and "Exxor" D30 (all manufactured by ExxonMobil Chemical Company), and CS gasoline (manufactured by JX Nippon Oil & Energy Corporation).

[0056] The silicone resin composition of the present invention may contain various fillers, which can improve the strength of the cured product. It may also contain the colored dyes described in JP-A-2002-244279 and the colored pigments described in WO-A-2008 / 056588, and when used in a printing plate correction liquid, it can color the corrections to make them easier to see.

[0057] The method for producing the silicone resin composition of the present invention can be, for example, a method of mixing (a) silicone resin, (b) silane compound, (c) titanium compound, and if necessary (d) silicone oil and other components in a solvent. It is more preferable to prepare a solution containing (a) silicone resin and (d) silicone oil and a solution containing (b) silane compound, respectively, mix them, and then add (c) titanium compound and mix them.

[0058] More specifically, the solvent, (a) silicone resin, and (d) silicone oil are put into a container, and the components are stirred and mixed using a mixing device such as a mixer until they become uniform. The obtained mixed liquid is bubbled with dry gas such as dry air or dry nitrogen for 10 minutes or more to remove moisture, which is preferable from the viewpoint of maintaining the reactivity of the silicone composition and improving the pot life. Next, the solvent and (b) silane compound are put into another container, and the components are stirred and mixed until they become uniform. It is preferable to put the above-mentioned mixed liquid into the obtained mixed liquid, and finally put in (c) titanium compound and stir and mix.

[0059] The silicone resin composition of the present invention has excellent curing properties and cures in a short time even at room temperature, and therefore can be suitably used, for example, in a plate surface correction fluid for a waterless lithographic printing plate or an ink repellent layer for a waterless lithographic printing plate precursor.

[0060] A waterless lithographic printing plate precursor is a plate before printing areas / non-printing areas are formed on a waterless lithographic printing plate having an ink-receptive layer and an ink-repellent layer on a substrate, and has an ink-receptive layer and an ink-repellent layer on the substrate.

[0061] The substrate may be any of the dimensionally stable substrates conventionally used for lithographic printing plates, such as paper, metal plate, glass plate, and film. Among these, aluminum plate is preferred because it is extremely dimensionally stable. Polyethylene terephthalate film is also preferred as a flexible substrate for light printing.

[0062] The ink-receiving layer is preferably a thermosensitive layer, which has a function of converting the laser light used for drawing into heat (light-to-heat conversion), and more preferably has a function of decomposing at least the surface of the thermosensitive layer, increasing its solubility in a developer, or decreasing its adhesive strength with the ink-repelling layer, due to the generated heat. Examples of such a thermosensitive layer include the thermosensitive layers described in WO 2016 / 076286.

[0063] The ink-repellent layer is preferably a layer formed from the silicone resin composition described above. The ink-repellent layer can be formed, for example, by applying the silicone resin composition described above and drying it as necessary. Such an ink-repellent layer has excellent ink repellency and can suppress background scumming. In addition, by containing the (b) silane compound, the layer has excellent adhesion to the base and can improve adhesion to the ink-receiving layer.

[0064] The plate surface correction fluid for the waterless lithographic printing plate of the present invention (hereinafter sometimes abbreviated as "plate surface correction fluid") is made of the silicone resin composition of the present invention described above. If necessary, it may further contain a solvent, or the solvent may be removed by drying. The plate surface correction fluid of the present invention has excellent ink repellency, so that it can suppress background scumming. In addition, by containing (b) a silane compound, it has excellent adhesion to the base, so that it can improve adhesion to the ink repellent layer. In particular, it has excellent adhesion to the highly ink repellent ink repellent layer containing silicone oil, so it can be suitably used as a plate surface correction fluid for a waterless lithographic printing plate having a highly ink repellent ink repellent layer.

[0065] Next, a method for correcting the plate surface of a waterless lithographic printing plate using the plate surface correction liquid of the present invention will be described. The plate surface correction liquid of the present invention is applied to the part where the ink-receptive layer is exposed due to scratches on the ink-repellent layer, or the part where the ink-receptive layer of the image area to be changed to a non-image area is exposed. For applying the plate surface correction liquid, it is preferable to use an application tool such as a brush, a cotton swab, a sponge, a dropper, or a syringe. It is also preferable to clean the correction area using a hydrocarbon solvent before applying the plate surface correction liquid, which can further improve adhesion. Examples of the hydrocarbon solvent include paraffinic hydrocarbons, isoparaffinic hydrocarbons, cycloparaffinic hydrocarbons, and aromatic hydrocarbon solvents. Two or more of these may be used.

[0066] After application, the plate surface correction liquid is cured, if necessary, by heating or exposure to light, to form a thin silicone rubber film, which imparts ink repellency to the desired areas.

[0067] The silicone resin composition of the present invention can be cured by, for example, applying it onto a substrate, exposing it to air at a temperature of 0° C. or higher and a humidity of 20% to 100%, and drying the solvent as necessary. Such a cured product has excellent ink repellency, and can be suitably used as an ink repellent layer of a waterless lithographic printing plate. Such a waterless lithographic printing plate has an ink-receptive layer and an ink repellent layer containing the above-mentioned cured product on a substrate. Here, the cured product of the silicone resin may be present as the entire ink repellent layer, or may be present as a part of the ink repellent layer. In the former case, for example, a waterless lithographic printing plate obtained from a waterless lithographic printing plate precursor using the above-mentioned silicone resin composition as the ink repellent layer can be mentioned. In the latter case, for example, a waterless lithographic printing plate in which a non-printing area is formed on a waterless lithographic printing plate having a desired ink repellent layer using the above-mentioned plate surface correction liquid can be mentioned.

[0068] Next, a method for producing a waterless lithographic printing plate from a waterless lithographic printing plate precursor using the above-mentioned silicone resin composition as an ink-repellent layer will be described. The method for producing a waterless lithographic printing plate preferably includes a step of exposing the waterless lithographic printing plate precursor according to an image (exposure step), and a step of applying a physical stimulus to the exposed waterless lithographic printing plate precursor and removing the ink-repellent layer in the exposed area (development step).

[0069] First, the exposure step will be described. The light source used in the exposure step is one having an emission wavelength range of 300 nm to 1,500 nm. Among these, laser light having a wavelength of 780 nm, 830 nm, or 1,064 nm is preferably used for exposure.

[0070] Next, the developing step will be described. The ink-repellent layer in the exposed area is removed by applying a physical stimulus to the waterless lithographic printing plate precursor after exposure. Examples of methods for applying the physical stimulus include (i) wiping the plate surface with a nonwoven fabric, absorbent cotton, cloth, sponge, etc. soaked in a developer, (ii) pretreating the plate surface with a developer and then rubbing with a rotating brush while showering with tap water, etc., and (iii) spraying high-pressure water, hot water, or steam onto the plate surface.

[0071] Examples of the developer include those exemplified as developers in WO 2016 / 076286.

[0072] Prior to development, a pretreatment may be performed in which the exposed waterless lithographic printing plate precursor is immersed in a pretreatment liquid for a certain period of time. Examples of the pretreatment liquid include those exemplified as pretreatment liquids in WO 2016 / 076286.

[0073] In addition, a dye may be added to the pretreatment liquid and / or the developer to dye the ink-receiving layer in the image area simultaneously with development, or the ink-receiving layer in the image area may be dyed with a treatment liquid containing a dye after development. By dyeing the ink-receiving layer in the image area, the visibility of the image area and the measurement accuracy of the halftone dots can be improved. Examples of dyes include crystal violet, Victoria Pure Blue, and Astrazone Red.

[0074] The waterless lithographic printing plate of the present invention is a lithographic printing plate capable of printing without using dampening water, and can obtain a printed matter by transferring ink from the ink-receptive layer directly or via a blanket to a printing substrate such as thin paper, thick paper, film, label, etc. The waterless lithographic printing plate of the present invention can suppress background scumming because the ink-repellent layer has excellent ink repellency. EXAMPLES

[0075] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these. In addition, the names of the compounds used, for which abbreviations are used, are shown below. ((a) Silicone resin) DMS-S35: a structure represented by general formula (3) (R 7 : Hydroxyl group, R 8 Polydimethylsiloxane having silanol groups at both ends (Gelest, Inc., weight average molecular weight: 49,000, number of silanol groups in molecule: 2, dynamic viscosity: 50 cm 2 / s) DMS-S21: a structure represented by general formula (3) (R 7 : Hydroxyl group, R 8 e: methyl group, e: 54, f: 0, g: 0) at both ends of the silanol group (Gelest, Inc., weight average molecular weight: 4,200, number of silanol groups in the molecule: 2, kinematic viscosity: 0.9 to 1.2 cm 2 / s) DMS-S27: a structure represented by general formula (3) (R 7 : Hydroxyl group, R 8 Polydimethylsiloxane having silanol groups at both ends (Gelest, Inc., weight average molecular weight: 18,000, number of silanol groups in molecule: 2, dynamic viscosity: 7-8 cm 2 / s) DMS-S51: a structure represented by general formula (3) (R 7 : Hydroxyl group, R 8 Polydimethylsiloxane having silanol groups at both ends (Gelest, Inc., weight average molecular weight: 139,000, number of silanol groups in molecule: 2, kinematic viscosity: 900 to 1,500 cm3) 2 / s) TF13: A structure represented by general formula (3) (R 7 : Hydroxyl group, R 8 Polydimethylsiloxane with silanol groups at both ends (manufactured by Dow Toray Co., Ltd., weight average molecular weight: 400,000, number of silanol groups in molecule: 2) having methyl groups, e: 5,400, f: 0, g: 0 ((b) Silane Compound) QOS: A structure represented by general formula (2) (R 4 : Methyl group, R 5 Tetrakis(methylethylketoxime)silane solution having an ethyl group (n: 4), concentration 50% by mass, containing solvent toluene (SIT7289.0, manufactured by Gelest, Inc.) VTO: A structure represented by general formula (2) (R 4 : Methyl group, R 5Vinyl tris(methyl ethyl ketoxime) silane having an ethyl group (n: 3), tech-95 (SIV9280.0, manufactured by Gelest, Inc.) (Other silane compounds) 4AS: Tetraacetoxysilane MTA: Methyltriacetoxysilane ((c) Titanium compounds) TC-750: a compound having a structure represented by general formula (1) (R 1 : Methyl group, R 2 Diisopropoxybis((4-ethoxy-4-oxobut-2-en-2-yl)oxy)titanium solution having ethoxy group, r: 0, m: 2, concentration 97.5% by weight, containing solvent 2-propanol ("Orgatics (registered trademark)" TC-100, manufactured by Matsumoto Fine Chemical Co., Ltd.) TC-100: a structure represented by general formula (1) (R 1 : Methyl group, R 2 : methyl group, r: 0, m: 2) diisopropoxybis((4-oxopent-2-en-2-yl)oxy)titanium solution, concentration 75% by weight, containing solvent 2-propanol ("Orgatics (registered trademark)" TC-100, manufactured by Matsumoto Fine Chemical Co., Ltd.) Narsemtitanium: A structure represented by the general formula (1) (R 1 : Methyl group, R 2 Di-n-butoxybis((4-oxopent-2-en-2-yl)oxy)titanium solution having a methyl group, r: 0, m: 2), concentration: 73% by weight, containing solvent: n-butanol ("Nasem (registered trademark)" titanium, manufactured by Nippon Chemical Industry Co., Ltd.) (Other titanium compounds) TA-10: tetraisopropoxy titanium ("Orgatics (registered trademark)" TA-10, manufactured by Matsumoto Fine Chemical Co., Ltd.) TC-401: tetrakis((4-oxopent-2-en-2-yl)oxy)titanium solution, concentration 65% by weight, containing solvent 2-propanol ("Orgatics (registered trademark)" TC-401, manufactured by Matsumoto Fine Chemical Co., Ltd., concentration 65% by weight, containing solvent 2-propanol) (Tin compounds) DBTDA: Dibutyltin diacetate ((d) Silicone oil) KF-96-50cs: (Shin-Etsu Chemical Co., Ltd.) (others) APTMS: 3-aminopropyltrimethoxysilane.

[0076] (Production Example 1: Production of highly ink-repellent waterless lithographic printing plate) A highly ink-repellent waterless lithographic printing plate was prepared by the following method.

[0077] The following heat insulating layer composition solution was applied onto a 0.24 mm thick degreased aluminum substrate (manufactured by Mitsubishi Aluminum Co., Ltd.) and dried at 200° C. for 90 seconds to provide a heat insulating layer with a thickness of 6.0 μm. The heat insulating layer composition solution was obtained by mixing the following components with stirring at room temperature. <Thermal insulation layer composition solution> Polymer having active hydrogen: Epoxy resin: "Epicoat (registered trademark)" 1010 (manufactured by Japan Epoxy Resins Co., Ltd.): 35 parts by mass Polymer having active hydrogen: Polyurethane: "Sanprene (registered trademark)" LQ-T1331D (manufactured by Sanyo Chemical Industries, Ltd., solid content concentration: 20% by mass): 375 parts by mass Aluminum chelate: Aluminum chelate ALCH-TR (Kawaken Fine Chemical Co., Ltd.): 10 parts by weight Leveling agent: Disparlon (registered trademark) LC951 (Kusumoto Chemicals Co., Ltd., solid content: 10% by mass): 1 part by mass Titanium oxide: 60 parts by weight of "Tipake (registered trademark)" CR-50 (manufactured by Ishihara Sangyo Kaisha, Ltd.) in N,N-dimethylformamide dispersion (50% by weight of titanium oxide) N,N-dimethylformamide: 730 parts by mass Methyl ethyl ketone: 250 parts by mass.

[0078] Next, the following heat-sensitive layer composition solution was applied onto the heat insulating layer and dried by heating at 140° C. for 90 seconds to provide a heat-sensitive layer having a thickness of 1.5 μm. The heat-sensitive layer composition solution was obtained by mixing the following components by stirring at room temperature. <Thermosensitive layer composition solution-1> Infrared absorbing dye: PROJET 825LDI (manufactured by Avecia): 16.0 parts by weight Organic complex compound: Titanium-n-butoxide bis(acetylacetonate): "Nacem (registered trademark)" titanium (manufactured by Nippon Kagaku Sangyo Co., Ltd., concentration: 73% by mass, containing 27% by mass of n-butanol as a solvent): 15.0 parts by mass Phenol formaldehyde novolac resin: "Sumilite Resin (registered trademark)" PR53195 (manufactured by Sumitomo Bakelite Co., Ltd.): 60 parts by mass Polyurethane: "Nippolan (registered trademark)" 5196 (manufactured by Nippon Polyurethane Co., Ltd., concentration: 30% by mass, containing 35% by mass of methyl ethyl ketone and 35% by mass of cyclohexanone as solvents): 25 parts by mass Tetrahydrofuran: 1044 parts by mass.

[0079] Next, the following ink repellent layer composition solution-1, prepared immediately before coating, was coated on the heat-sensitive layer and heated at 140°C for 80 seconds to provide an ink repellent layer with an average thickness of 2.5 µm, thereby obtaining a highly ink-repellent waterless lithographic printing plate precursor. Note that the ink repellent layer composition solution-1 was obtained by mixing the following components by stirring at room temperature. <Ink repellent layer composition solution-1> α,ω-divinylpolydimethylsiloxane: TF22 (weight average molecular weight 100,000, manufactured by Dow Toray Co., Ltd.): 80.0 parts by mass Silicone oil: KF-96-50cs (polydimethylsiloxane with methyl groups blocked at both ends. Weight average molecular weight: 3780, surface tension: 20.8 mN / m, boiling point: >150°C, manufactured by Shin-Etsu Chemical Co., Ltd.): 10.0 parts by mass Methylhydrogensiloxane HMS305 (GELEST Inc.): 2.95 parts by mass Vinyltris(methylethylketoxyimino)silane: 0.88 parts by mass Platinum catalyst SRX212 (Dow Toray Industries, Inc.): 6.17 parts by mass Isoparaffinic hydrocarbon solvent "Isopar (registered trademark)" E (manufactured by ExxonMobil Chemical Company): 900 parts by mass.

[0080] The obtained highly ink-repellent waterless lithographic printing plate precursor was exposed to light using a CTP exposure machine PlateRite 8800E (manufactured by Dai Nippon Screen Mfg. Co., Ltd.) at an exposure energy of 130 mJ / cm 2 Exposure was performed under the conditions of (drum rotation speed: 232 rpm). The exposed image was a 20 mm x 650 mm halftone dot image (AM175 lines (2,400 dpi)) with a dot area ratio of 50% in the center of a 550 mm x 650 mm waterless lithographic printing plate precursor. CP-Y (manufactured by Toray Industries, Inc.) was used as a pretreatment liquid, tap water was used as a developer, and the exposed plate was passed through an automatic developing machine TWL-1160F (manufactured by Toray Industries, Inc.) at a speed of 80 cm / min to produce a highly ink-repellent waterless lithographic printing plate.

[0081] The evaluations in the examples and comparative examples were carried out in the following manner.

[0082] (1) Curability The silicone resin compositions obtained in Examples 1 to 23 and each Comparative Example were applied with a brush onto the image of the highly ink-repellent waterless planographic printing plate obtained in Production Example 1, and the drying state of the coating film was checked every 5 minutes while drying under conditions of a temperature of 23±2°C and a humidity of 50±5%, and the time until the coating film was cured and dried was determined to evaluate the curability. The state where the coating film was not indented by a fingerprint when the center of the coating surface was pinched firmly between the thumb and index finger, the coating film was not moved, and the coating surface was not scratched when the center of the coating surface was rubbed rapidly and repeatedly with the fingertips was considered to be cured and dried. The coating film was considered to have passed the test when the curing and drying time was within 30 minutes.

[0083] (2) Adhesion The silicone resin compositions obtained in each of the Examples and Comparative Examples were applied with a brush onto the image of the highly ink-repellent waterless lithographic printing plate obtained in Production Example 1, and dried under conditions of a temperature of 23±2°C and a humidity of 50±5% to obtain a cured product. The curing time was determined as the time required for the product to become cured and dry in the evaluation of curability (1).

[0084] The resulting highly ink-repellent waterless lithographic printing plate (6 cm x 6 cm) having the cured product was attached to a continuous load type friction fastness tester and rubbed 150 times back and forth at a load of 100 g using a hook-and-loop fastener: New Ecomagic A8693Y-71 (Kuraray Fastening Co., Ltd.) cut to a size of 2 cm x 3 cm. The cured product after rubbing was visually inspected and rated on the following 5-point scale. A score of 3 or more was considered a pass. 5 points: No peeling of the cured product was observed 4 points: The peeled area of ​​the cured product is less than 5%. 3 points: Peeling area of ​​the cured product is 5% or more but less than 10%. 2 points: Peeling area of ​​the cured product is 10% or more but less than 50%. 1 point: Peeling area of ​​the cured material is 50% or more.

[0085] (3) Ink repellency The silicone resin compositions obtained in each of the Examples and Comparative Examples were applied with a brush onto the image of the highly ink-repellent waterless lithographic printing plate obtained in Production Example 1, and then dried under conditions of a temperature of 23±2°C and a humidity of 50±5% to obtain a cured product. The curing time was determined as the time required for the product to become cured and dry in the evaluation of curability (1).

[0086] The resulting highly ink-repellent waterless lithographic printing plate having the cured product was attached to a printing machine: OLIVER 466SD, and offset printing was performed using UV ink UV171CT TW-M (manufactured by T&K TOKA Corporation) by supplying ink to the printing plate with an ink roller and transferring the ink to thin coated paper via a blanket. The amount of UV ink supplied was adjusted so that the reflection density of the parts corresponding to the non-image areas in the resulting print was 0.20 (black), and the coated paper to which the ink had been transferred was irradiated with ultraviolet light to obtain a print. The ultraviolet light irradiation was performed with an output of 120 W / cm. 2 A metal halide lamp was used, the focal length was 150 mm, the width of the lamp house in the flow direction was 100 mm, and the conveyor speed was 5 m / min. The reflection density of the part of the printed matter corresponding to the cured product of the silicone resin composition was measured to evaluate the ink repellency. The evaluation was made according to the following criteria, with 3 points or more being considered a pass. 5 points: Reflection density 0.00~0.10 4 points: Reflection density 0.10~0.15 3 points: Reflection density 0.15~0.25 2 points: Reflection density 0.15~0.40 1 point: Reflection density 0.40 or more.

[0087] (4) Background staining temperature A printing test machine was prepared by connecting an ultraviolet irradiation device with a built-in variable speed conveyor to the paper discharge section of a sheet-fed printing machine Oliver 266EPZ (manufactured by Sakurai Graphic Systems Co., Ltd.). The waterless lithographic printing plate obtained in Example 24 was attached to this printing test machine. The temperature of the ink roller was controlled using a chiller to change the plate surface temperature of the waterless lithographic printing plate, and offset printing was performed by supplying ink to the printing plate using an ink roller using UV ink UV171CT TW-M (manufactured by T&K TOKA Co., Ltd.) and transferring the ink to a thin coated paper via a blanket. The amount of UV ink supplied was adjusted so that the reflection density of the solid printed area in the obtained print was 1.8 (black), and the coated paper to which the UV ink had been transferred was irradiated with ultraviolet light to obtain a print. The ultraviolet light irradiation was performed with an output of 120 W / cm. 2 A metal halide lamp was used, the focal length was 150 mm, the width of the lamp house in the flow direction was 100 mm, the conveyor speed was 5 m / min. The surface temperature of the waterless lithographic printing plate was measured using a non-contact thermometer, and the presence or absence of background scumming in the non-printing areas was observed for each temperature, and the lowest temperature at which background scumming was observed was taken as the background scumming onset temperature.

[0088] (5) Number of prints For the waterless lithographic printing plate obtained in Example 24, continuous printing was continued in the same manner as in (4) above while maintaining the smearing starting temperature. The smearing condition of the printed matter was observed every 5,000 sheets, and the number of sheets until deterioration was confirmed visually was recorded as the number of prints that could be used.

[0089] Example 1 Into a container, 45 g of "Isopar (registered trademark)" E was added as a solvent, and (a) 10 g of DMS-S35 was added as a silicone resin, and the components were mixed and stirred until they were uniform. The obtained mixed liquid was bubbled with dry nitrogen for 10 minutes or more to remove water from the liquid. Next, in another container, 45 g of "Isopar (registered trademark)" E was added as a solvent, and (b) 0.60 g of VTO and 0.30 g of QOS were added as silane compounds, and the obtained mixed liquid was added while stirring. Finally, 1.0 g of TC-750 was added as a titanium compound (c) and mixed and stirred to obtain a silicone resin composition. The obtained silicone resin composition was evaluated as described above, and the results are shown in Table 1.

[0090] Example 2 In a container, 45 g of "Isopar (registered trademark)" E as a solvent, (a) 10 g of DMS-S35 as a silicone resin, and (d) 0.50 g of KF-96-50cs as a silicone oil were added, and the components were stirred and mixed until they were uniform. The obtained mixed liquid was bubbled with dry nitrogen for 10 minutes or more to remove water from the liquid. Next, in another container, 45 g of "Isopar (registered trademark)" E as a solvent, (b) 0.60 g of VTO and 0.30 g of QOS as silane compounds were added, and the obtained mixed liquid was added while stirring. Finally, 1.0 g of TC-750 as a titanium compound (c) was added and stirred and mixed to obtain a silicone resin composition. The obtained silicone resin composition was evaluated as described above, and the results are shown in Table 1.

[0091] Examples 3 to 11 A silicone resin composition was prepared and evaluated in the same manner as in Example 2, except that the composition of each component of the silicone resin composition was changed as shown in Table 1. The evaluation results are shown in Table 1.

[0092] [Table 1]

[0093] Comparative Examples 1 to 7 A silicone resin composition was prepared and evaluated in the same manner as in Example 2, except that the composition of each component of the silicone resin composition was changed as shown in Table 2. However, evaluation was not performed for Comparative Example 4 because it gelled during stirring and mixing. The evaluation results are shown in Table 2.

[0094] [Table 2]

[0095] Examples 12 to 23 Silicone resin compositions were prepared and evaluated in the same manner as in Example 2, except that the blending ratios of the components of the silicone resin compositions were changed as shown in Tables 3 and 4. The evaluation results are shown in Tables 3 and 4.

[0096] [Table 3]

[0097] [Table 4]

[0098] Example 24 Instead of the ink-repellent layer composition solution-1, the silicone resin composition obtained in Example 4 was used, and instead of drying at 140°C for 80 seconds, drying was performed under conditions of a temperature of 23±2°C and a humidity of 50±5% for 30 minutes to form an ink-repellent layer made of a cured product of the silicone resin composition with an average film thickness of 2.5 μm. A waterless lithographic printing plate precursor was obtained in the same manner as in Production Example 1. When the ink-repellent layer was formed, the drying state of the coating film was checked every 5 minutes, and the time required for curing and drying was 10 minutes, indicating good curability. In addition, a waterless lithographic printing plate was produced using the obtained waterless lithographic printing plate precursor in the same manner as in Production Example 1, and the above-mentioned evaluation was performed. The background scumming start temperature was 35°C, and the number of prints was 20,000, indicating good printability.

Claims

1. A silicone resin composition comprising: (a) a silicone resin having two or more silanol groups; (b) a silane compound having an oxime group directly bonded to Si; and (c) a titanium compound having a structure represented by the following general formula (1): [Formula 1] (In the above general formula (1), R １ and R ２ each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms. ３ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; m represents an integer of 1 to 3; and r represents an integer of 0 to 2.

2. The silicone resin composition according to claim 1, further comprising (d) a silicone oil.

3. 3. The silicone resin composition according to claim 1, wherein in the general formula (1), r is 0.

4. In the general formula (1), [ ] ｍ 3. The silicone resin composition according to claim 1, wherein the structure represented in the formula (I) is a (4-oxopent-2-en-2-yl)oxy group, a (4-alkoxy-4-oxobut-2-en-2-yl)oxy group having a total of 5 to 12 carbon atoms, or a (4-aryloxy-4-oxobut-2-en-2-yl)oxy group having a total of 10 to 16 carbon atoms.

5. 3. The silicone resin composition according to claim 1, wherein the content of the titanium compound (c) having a structure represented by general formula (1) is 1.5 parts by mass to 35 parts by mass per 100 parts by mass of the silicone resin (a) having two or more silanol groups.

6. 3. The silicone resin composition according to claim 1, wherein the (b) silane compound having an oxime group directly bonded to Si has a structure represented by the following general formula (2): [chemical 2] (In the above general formula (2), R ４ and R ５ R each independently represents an alkyl group having 1 to 8 carbon atoms. ６ represents an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 1 to 8 carbon atoms. n represents an integer of 1 to 4.

7. 3. The silicone resin composition according to claim 1, wherein the content of the (b) silane compound having an oxime group directly bonded to Si is 2.5 parts by mass to 35 parts by mass per 100 parts by mass of the (a) silicone resin having two or more silanol groups.

8. 3. A surface correction fluid for waterless lithographic printing plates comprising the silicone resin composition according to claim 1 or 2.

9. A cured product of the silicone resin composition according to claim 1 or 2.

10. A waterless lithographic printing plate having, on a substrate, an ink-receptive layer and an ink-repellent layer comprising the cured product according to claim 9.

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