JPH071849A - Planographic printing base plate and production thereof - Google Patents

Abstract

PURPOSE:To obtain a planographic printing plate requiring no development and having high printing durability and high dimensional accuracy and capable of obtaining printed matter of a sharp image free from background staining by constituting the planographic printing plate of a hydrophilic layer containing a specific microencapsulated hydrophilic component and a hydrophilic binder polymer and a support. CONSTITUTION:A thermal planographic printing base plate is constituted of a hydrophilic layer converted to an image part by heat and containing a microencapsulated hydrophilic component and a hydrophilic binder polymer and a support. The hydrophilic binder polymer is three-dimensionally crosslinked and has the hydrophilic component in a microcapsule and a functional group chemically bonded after the destruction of the microcapsule. Further, the hydrophilic component in the microcapsule has the functional group chemically bonded to the hydrophilic binder polymer after the destruction of the microcapsule. The thermal planographic printing base plate is obtained by the printing due to a thermal recording means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct heat-sensitive lithographic printing plate precursor for offset printing which does not require development and is excellent in printing durability, and a plate-making method thereof.

[0002]

2. Description of the Related Art With the widespread use of computers, various plate making methods have been proposed along with plate material construction. From a practical point of view, a method in which a positive or negative film is prepared from an original plate and baked on a lithographic printing original plate is generally used, but an electrophotographic plate or a silver salt photographic plate is prepared directly from the original plate without using the film. , Or electronic typesetting, DTP
Introducing a so-called computer-to-plate (CTP) type lithographic plate that can be printed directly on the plate material with a laser or thermal head without visualizing the printed image information edited and produced by (Desktop Publication). I am trying to do it. Although these have not been put to practical use yet, CTS type plate materials in particular can be streamlined and shortened in the plate making process, and material costs can be reduced, so CTS can be used.
There are great expectations in the fields such as newspaper production, which has been completed.

As such a CTP plate material, a photosensitive type, a heat sensitive type, or a type of plate making with electric energy is known. Plate materials made with photosensitive type or electric energy are not only more expensive than conventional PS plates, but their manufacturing equipment is also large and expensive, so these plate materials and plate making processes are put to practical use. Has not reached. Furthermore, they also have the problem of disposal of the developer.

Several heat-sensitive plate materials have been developed for light printing applications including in-house printing. JP 63-
In Japanese Patent No. 64747 and Japanese Patent Application Laid-Open No. 11-13290, a hot-melt resin and a thermoplastic resin dispersed in a heat-sensitive layer provided on a support are melted by thermal printing, and a heating portion is changed from hydrophilic to lipophilic. The plate materials to be changed to US Patent Nos. 4,034,183 and 4,063,949 are
Each of the plate materials is disclosed in which a hydrophilic polymer provided on a support is irradiated with a laser to eliminate the hydrophilic group and convert to lipophilic. However, these plate materials have a problem that the non-image area is soiled due to the ink reception by the hot-melt substance existing on the plate surface, the printing durability is insufficient, and the degree of freedom in the plate material design is low. was there.

Japanese Unexamined Patent Publication (Kokai) No. 3-108588 and Japanese Unexamined Patent Publication (Kokai) No. 5
Japanese Patent No. 8575 discloses a plate material in which a heat-sensitive recording layer made of a micro-encapsulated heat-melting substance and a binder resin is provided on a support and a heating part is changed to be lipophilic. However, none of the microencapsulated heat-melted substances had reactivity, and printing durability was not satisfactory. On the other hand, JP-A-62-164596 and JP-A-62-164049 disclose a lithographic printing original plate having a recording layer comprising a blocked isocyanate together with a binder polymer containing an active hydrogen on a support having a hydrophilic surface, and its precursor. A method is disclosed. However, this plate material requires a developing process for removing the non-printed portion after printing.

Further, one of the direct type lithographic printing materials is a direct drawing type lithographic printing material in which an image portion is formed on the surface of the hydrophilic layer by an external means such as ink jet or toner transfer.
Japanese Unexamined Patent Publication No. 62-1587 discloses a plate material in which a non-reactive, heat-fusible substance encapsulated in microcapsules is applied and a toner-receiving layer is formed by heating printing. However, the lipophilic toner or the like is fixed to the formed toner receiving layer to form a printing plate, and the image portion is not formed after printing. Thus, the conventional heat-sensitive lithographic printing plate material has poor printing durability or lipophilicity,
It was limited to applications such as light printing. Further, in some of the plate making processes, a developing process was required.

[0007]

SUMMARY OF THE INVENTION As described above, the prior art has problems in carrying out at a commercial level in terms of plate performance, plate making device, plate making workability, or cost of plate material, plate making, and device. . The present invention is intended to solve the above problems of the conventional direct type offset printing plate material. That is, an object of the present invention is to provide a lithographic printing plate precursor that provides a lithographic printing plate with high printing durability and high dimensional accuracy, and that can obtain a printed image with a clear image without background stains at a low price. . Still another object is to provide a lithographic printing plate precursor and a lithographic printing plate precursor for the lithographic printing plate precursor that do not require a developing process such as waste treatment such as a developing solution in the plate making process and can be used for plate making without using a dedicated large-scale and expensive plate making device. That is.

[0008]

That is, the present invention relates to a heat-sensitive material comprising a support and a hydrophilic layer containing a microencapsulated lipophilic component which is converted into an image area by heat and a hydrophilic binder polymer. It is a planographic printing original plate,
The hydrophilic binder polymer is three-dimensionally crosslinked,
And, the lipophilic component in the microcapsule has a functional group that chemically bonds with the capsule after destruction, and the lipophilic component in the microcapsule has a functional group that chemically bonds with the hydrophilic binder polymer after destruction of the capsule. The present invention provides a heat-sensitive lithographic printing plate having.

The present invention also provides a heat-sensitive lithographic printing material comprising a support and a hydrophilic layer containing a microencapsulated lipophilic component which is converted into an image area by heat and a hydrophilic binder polymer. The hydrophilic binder polymer has a functional group capable of three-dimensional cross-linking, a lipophilic component in the microcapsule and a functional group that chemically bonds to the microcapsule after the capsule is destroyed, and the lipophilic component in the microcapsule is a capsule. The present invention provides a heat-sensitive lithographic printing material having a functional group that chemically bonds with the hydrophilic binder polymer after the destruction. Furthermore, the present invention provides the above-mentioned heat-sensitive lithographic printing plate precursor and a method for making a heat-sensitive lithographic printing material, and a printing plate comprising the same.

In the lithographic printing plate precursor of the present invention, the hydrophilic layer made of a hydrophilic binder polymer having a three-dimensional crosslinked structure repels ink and constitutes the main component of the non-image area. By having a three-dimensional crosslinked structure, the hydrophilic layer does not swell with dampening water, maintains the adhesive strength with the support and the mechanical properties of the hydrophilic layer, and exhibits high printing durability.

The three-dimensional crosslinked structure of the hydrophilic binder polymer may be formed simultaneously with printing or after printing. Those in which the hydrophilic binder polymer does not have a three-dimensional crosslinked structure before plate making can also be used as the lithographic printing material in the present invention. From the viewpoint of preventing scratches during handling and preventing the thermally melted hydrophilic layer component from adhering to the thermal head when printing with a thermal head, it is preferable to finish forming the three-dimensional crosslinked structure before plate making. .

The hydrophilic binder polymer having a three-dimensional crosslinked structure in the present invention means poly (meth) acrylate type, polyoxyalkylene type, polyurethane type, epoxy ring-opening addition polymerization type, poly (meth) acrylic acid type, Poly (meth) acrylamide-based, polyester-based, polyamide-based, polyamine-based, polyvinyl-based, polysaccharide-based, or a composite thereof, etc., having a carboxyl group, a phosphoric acid group, a sulfonic acid group, an amino group or a salt thereof in the side chain. , A networked polymer composed of carbon-carbon bonds containing one or more hydrophilic functional groups such as a hydroxyl group, an amide group, and a polyoxyethylene group, and a hetero atom composed of oxygen, nitrogen, sulfur, and phosphorus. A networked polymer composed of carbon atoms or carbon-carbon bonds linked by at least one or more of Carboxyl groups on its side chain,
It is a networked polymer containing one or more kinds of hydrophilic functional groups such as a phosphoric acid group, a sulfonic acid group, an amino group or salts thereof, a hydroxyl group, an amide group and a polyoxyethylene group.

Among them, a hydroxyl group, a carboxyl group or an alkali metal salt thereof, a sulfonic acid group or an amine salt thereof, an alkali metal salt and an alkaline earth metal salt in the side chain,
A hydrophilic binder polymer having a repeating segment of an amino group or its hydrohalide salt, an amide group or a combination thereof, and a polyoxyethylene group as a part of the hydrophilic functional group and the main chain segment. Those having are preferable because they have high hydrophilicity. In addition to these, those having a urethane bond or a urea bond in the main chain or side chain of the hydrophilic binder polymer,
It is more preferable because not only the hydrophilicity but also the printing durability of the non-image area is improved.

The proportion of the hydrophilic functional group in the polymer can be determined experimentally by the method described below for each sample depending on the type of the main chain segment and the type of the hydrophilic functional group used. Go! That is, the hydrophilicity of the hydrophilic binder polymer of the present invention, the printing test described in the examples of the hydrophilic binder polymer cross-linked on the support, the presence or absence of ink adhesion to the printing paper, or before and after printing. Difference in reflection density of paper in non-image area (for example, reflection density meter DM4 manufactured by Dainippon Screen Mfg. Co.
00) or the oil-in-water contact angle measurement method using water-kerosene (for example, contact angle meter manufactured by Kyowa Interface Science, model CA-A) to evaluate whether kerosene adheres to the sample. .

When the former method is used for evaluation, the ink is observed with the naked eye and is allowed if ink stains are not recognized, and if it is recognized, it is not accepted, or the difference in reflection density between the non-image areas of the paper before and after printing is 0.02 or less. Is acceptable, and the case where it exceeds 0.02 is not acceptable. When evaluated by the latter method, for printing plates using low-viscosity inks, such as newspaper printing, the contact angle of the sample needs to be greater than about 150 degrees, and even 16
0 degree or more is preferable. For printing plates using high-viscosity inks that are kneaded before printing, greater than about 135 degrees is required.

The hydrophilic binder polymer of the present invention may optionally contain various other components described below. Specific examples of the three-dimensionally crosslinked hydrophilic binder polymer of the present invention are shown below.

As the hydrophilic binder polymer, (meth) acrylic acid or its alkali metal salt and amine salt, itaconic acid or its alkali metal salt and amine salt, 2-hydroxyethyl (meth) acrylate,
(Meth) acrylamide, N-monomethylol (meth)
Acrylamide, N-dimethylol (meth) acrylamide, allylamine or its hydrohalide,
3-Vinylpropionic acid or its alkali metal salt and amine salt, vinyl sulfonic acid or its alkali metal salt and amine salt, 2-sulfoethyl (meth) acrylate, polyoxyethylene glycol mono (meth) acrylate, 2-acrylamido-2- Carboxyl group, sulfonic acid group, phosphoric acid group, amino group or salts thereof, hydroxyl group, amide such as methylpropane sulfonic acid, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, allylamine or its hydrohalide A hydrophilic homo- or copolymer is synthesized by using at least one kind selected from hydrophilic monomers having a hydrophilic group such as a group and an ether group.

The hydrophilic binder polymer having a functional group such as a carboxyl group, an amino group or a salt thereof, a hydroxyl group and an epoxy group utilizes these functional groups,
Ethylene addition-polymerizable unsaturated groups such as vinyl group, allyl group, (meth) acrylic group or unsaturated groups introduced with ring forming groups such as cinnamoyl group, cinnamylidene group, cyanocinnamylidene group and p-phenylenediacrylate group. A containing polymer is obtained. If necessary, a monofunctional or polyfunctional monomer that can be copolymerized with the unsaturated group, a polymerization initiator described below, and other components described below are added, and the mixture is dissolved in a suitable solvent to adjust the dope. This is coated on a support, and after three-dimensional drying, or while also reacting with drying, three-dimensional crosslinking is carried out.

The hydrophilic binder polymer containing active hydrogen such as hydroxyl group, amino group and carboxyl group is
The compound is added to the above-mentioned active hydrogen-free solvent together with the isocyanate compound or the blocked polyisocyanate compound and the other components described below to prepare a dope, which is coated on the support and dried or after being combined with the reaction for three-dimensional crosslinking.

A monomer having a glycidyl group such as glycidyl (meth) acrylate or a carboxyl group or amino group such as (meth) acrylic acid can be used as a copolymerization component of the hydrophilic binder polymer.

The hydrophilic binder polymer having a glycidyl group can be used as a cross-linking agent in an α, ω-alkane or alkene dicarboxylic acid such as 1,2-ethanedicarboxylic acid or adipic acid, 1,2,3-propanetricarboxylic acid or tricarboxylic acid. Polycarboxylic acids such as meritic acid, 1,2-ethanediamine, diethylenediamine, diethylenetriamine, polyamine compounds such as α, ω-bis- (3-aminopropyl) -polyethylene glycol ether, ethylene glycol, propylene glycol, diethylene glycol, tetra Using a polyhydroxy compound such as oligoalkylene or polyalkylene glycol such as ethylene glycol, trimethylolpropane, glycerin, pentaerythritol, sorbitol, etc., and utilizing a ring-opening reaction with these, three-dimensional crosslinking That.

The hydrophilic binder polymer having a carboxyl group or an amino group is used as a cross-linking agent for ethylene or propylene glycol diglycidyl ether, polyethylene or polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglyceride. Glycidyl ether,
Three-dimensional crosslinking can be carried out by utilizing an epoxy ring-opening reaction using a polyepoxy compound such as trimethylolpropane triglycidyl ether.

The hydrophilic binder polymer is a polysaccharide such as a cellulose derivative, polyvinyl alcohol or a partially saponified product thereof, glycidol homo or copolymer,
Alternatively, in the case of using these as the base, three-dimensional crosslinking can be carried out by the above-mentioned method by utilizing the hydroxyl group contained therein and introducing the above-mentioned functional group capable of undergoing the crosslinking reaction.

2,4-tolylene diisocyanate, 2,4-tolylene diisocyanate, a polyol having a hydroxyl group at the polymer end such as polyoxyethylene glycol, or a polyamine having an amino group at the polymer end,
By introducing an ethylene addition-polymerizable unsaturated group or a ring-forming group into a hydrophilic polyurethane precursor synthesized from a polyisocyanate such as 1,6-hexamethylene diisocyanate or isophorone diisocyanate to prepare a hydrophilic binder polymer, Can be three-dimensionally crosslinked.

When the synthesized hydrophilic polyurethane precursor has an isocyanate group terminal, glycerol mono (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, N-mono Methylol (meth) acrylamide, N-dimethylol (meth) acrylamide,
React with compounds having active hydrogen such as (meth) acrylic acid, cinnamic acid and cinnamic alcohol. When the hydrophilic polyurethane precursor has a hydroxyl group or an amino group terminal, it is reacted with (meth) acrylic acid, glycidyl (meth) acrylate, 2-isocyanatoethyl (meth) acrylate and the like.

When the hydrophilic binder polymer is a polymer formed from a polybasic acid and a polyol or a polybasic acid and a polyamine, they are three-dimensionally crosslinked by heating after coating them on a support. When the hydrophilic binder polymer is casein, glue, gelatin, or the like, a water-soluble colloid-forming compound thereof may be three-dimensionally crosslinked by heating to form a network structure.

Further, a hydroxyl group-containing monomer such as 2-hydroxyethyl (meth) acrylate and vinyl alcohol, a homo or copolymer synthesized from allylamine, a partially saponified polyvinyl alcohol, a polysaccharide such as a cellulose derivative, a glycidol homo or copolymer, or a hydroxyl group. It is also possible to form a three-dimensionally crosslinked hydrophilic binder polymer by reacting a hydrophilic polymer containing an amino group or a polybasic acid anhydride having two or more acid anhydride groups in one molecule. Examples of the polybasic acid anhydride used in this reaction include ethylene glycol bis-anhydro trimellitate, glycerol tris-anhydro trimellitate, 1,3,3a, 4,5,9b hexahydro-5- (tetrahydro-2,5-dioxo- 3-
Furanyl) -naphtho [1,2-C] furan-1,3-dione, 3,3 ′, 4,4′-diphenylsulfonetetracaric acid dianhydride, 1,2,3,4-butanetetracarboxylic acid Examples thereof include dianhydride.

When the hydrophilic binder polymer is formed from a polyurethane having an isocyanate group at the terminal and an active hydrogen-containing compound such as polyamine or polyol, those compounds and other components described below are dissolved in a solvent. Alternatively, it may be dispersed and applied to a support to remove the solvent, and then cured at a temperature at which the microcapsules are not destroyed to perform three-dimensional crosslinking. In this case, the hydrophilicity may be imparted by introducing a hydrophilic functional group into either or both of the segments of the polyurethane or the active hydrogen-containing compound or the side chain. The segment and functional group exhibiting hydrophilicity may be appropriately selected from the above description.

As the polyisocyanate compound used in the present invention, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, tolidine diisocyanate, 1,4 6
Examples thereof include hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, lysine diisocyanate, triphenylmethane triisocyanate and bicycloheptane triisocyanate.

In some cases, it is sometimes preferable to block (mask) the isocyanate group by a known method for the purpose of preventing the isocyanate group from changing during handling before and after the coating step. For example, Keiji Iwata's "Plastic Materials Course Polyurethane Resin" published by Nikkan Kogyo Shimbun (1974), pages 51-52, Keiji Iwata's "Polyurethane Resin Handbook" published by Nikkan Kogyo Shimbun (198)
7), pages 98, 419, 423, 499, etc., according to the method described in, for example, acidic sodium sulfite, aromatic secondary amine, tertiary alcohol, amide, phenol, lactam,
A heterocyclic compound, a ketoxime or the like can be used for blocking. Among them, those having a low isocyanate regeneration temperature and being hydrophilic, for example, acidic sodium sulfite are preferable. An addition-polymerizable unsaturated group may be introduced into any of the above-mentioned non-blocked or blocked polyisocyanates and used for strengthening crosslinking or for reaction with a lipophilic component.

The degree of cross-linking of the hydrophilic binder polymer of the present invention, that is, the average molecular weight between cross-links varies depending on the type of segment used, the type and amount of associative functional groups, etc.
It may be decided according to the required printing durability. Usually, the average molecular weight between crosslinks is set in the range of 500 to 50,000. 5
If it is less than 00, it tends to be rather brittle, and the printing durability is impaired. If it exceeds 50,000, it may swell with dampening water and impair the printing durability. Considering the balance of both printing durability and hydrophilicity, it is preferably about 800 to 30,000, and more preferably about 1000 to 10,000.

In the above description, the hydrophilic binder polymer is (meth) acrylic acid or its alkali metal salt and amine salt, itaconic acid or its alkali metal salt and amine salt, 2-hydroxyethyl (meth) acrylate, ( (Meth) acrylamide, N-monomethylol (meth) acrylamide, N-dimethylol (meth)
Acrylamide, allylamine or its hydrohalide, 3-vinylpropionic acid or its alkali metal salt and amine salt, vinyl sulfonic acid or its alkali metal salt and amine salt,

2-sulfoethylene (meth) acrylate, polyoxyethylene glycol mono (meth) acrylate, 2-acrylamido-2-methylpropanesulfonic acid, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, allylamine or its halogen. Synthesized using at least one hydrophilic monomer having a hydrophilic group such as carboxylic acid group, sulfonic acid group, phosphoric acid, amino group or salts thereof, hydroxyl group, amide group, ether group, etc. It is preferable that the hydrophilic homo- or copolymer, or a hydrophilic binder polymer composed of polyoxymethylene glycol or polyoxyethylene glycol is three-dimensionally cross-linked by the above-mentioned method.

The hydrophilic binder polymer of the present invention may be used in combination with the following monofunctional monomers and polyfunctional monomers. Specifically, Shinzo Yamashita and Tosuke Kaneko, "Handbook of Crosslinking Agents" published by Taiseisha (1981), Kiyomi Kato, "Ultraviolet Curing System", Comprehensive Technology Center (1989), Kiyomi Kato, "UV / EB Curing" Handbook (raw materials) "Polymer Publishing Association (1985), supervised by Akamatsu Kiyoshi" Practical technology of new photosensitive resin "CMC, pp. 102-145, (198)
7) and the like, N, N'-methylenebisacrylamide, (meth) acryloylmorpholine, vinylpyridine, N-methyl (meth) acrylamide, N, N-
Dimethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminoneopentyl ( (Meth) acrylate,

N-vinyl-2-pyrrolidone, diacetone acrylamide, N-methylol (meth) acrylamide, p-styrene sulfonic acid or a salt thereof, methoxytriethylene glycol (meth) acrylate, methoxytetraethylene glycol (meth) acrylate,
Methoxy polyethylene glycol (meth) acrylate (PEG number average molecular weight 400), methoxy polyethylene glycol (meth) acrylate (PEG number average molecular weight 1000), butoxyethyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) ) Acrylate, phenoxy polyethylene glycol (meth) acrylate, nonylphenoxyethyl (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate,

Polyethylene glycol di (meth) acrylate (PEG number average molecular weight 400), polyethylene glycol di (meth) acrylate (PEG number average molecular weight 600), polyethylene glycol di (meth) acrylate (PEG number average molecular weight 1000) , Polypropylene glycol di (meth) acrylate (PPG number average molecular weight 400), 2,2-bis [4- (methacryloxyethoxy) phenyl] propane, 2,2-bis [4-
(Methacryloxy-diethoxy) phenyl] propane,
2,2-bis [4- (methacryloxy-polyethoxy)
Phenyl] propane or its acrylate, β-
(Meth) acryloyloxyethyl hydrogen phthalate, β- (meth) acryloyloxyethyl halide succinate, polyethylene or polypropylene glycol mono (meth) acrylate, 3-chloro-2
-Hydroxypropyl (meth) acrylate, 1,3-
Butylene glycol di (meth) acrylate,

1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate. , Isobornyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate,
Stearyl (meth) acrylate, isodecyl (meth)
Acrylate, cyclohexyl (meth) acrylate,
Tetrafurfuryl (meth) acrylate, benzyl (meth) acrylate, mono (2-acryloyloxyethyl) acid phosphate or its methacrylic compound, glycerin mono- or di (meth) acrylate, tris (2-acryloxyethyl) isocyanurate or its There are methacrylic compounds, N-phenylmaleimide, N- (meth) acryloxysuccinimide, N-vinylcarbazole, divinylethyleneurea, divinylpropyleneurea and the like.

When the three-dimensional crosslinking reaction of the hydrophilic binder polymer is carried out by using the ethylene addition polymerizable unsaturated group,
It is preferable in terms of reaction efficiency to use a known photopolymerization initiator or thermal polymerization initiator.

Examples of the photopolymerization initiator used in the present invention include benzoin, benzoin isobutyl ether, benzoin isopropyl ether, benzophenone, Michler's ketone, xanthone, thioxanthone, chloroxanthone, acetophenone, 2,2-dimethoxy-2-phenylacetophenone and benzyl. , 2,2-dimethyl-2
-Hydroxyacetophenone, (2-acryloyloxyethyl) (4-benzoylbenzyl) dimethyl ammonium bromide, (4-benzoylbenzyl) trimethylammonium chloride, 2- (3-dimethylamino-2-hydroxypropoxy) -3,4- Dimethyl-9H-thioxanthone-9-one mesochloride,

1-phenyl-1,2-propanedione-
2- (O-benzoyl) oxime, thiophenol, 2
-Benzothiazole thiol, 2-benzoxazole thiol, 2-benzimidazole thiol, diphenyl sulfide, decyl phenyl sulfide, di-n-butyl disulfide, dibenzyl sulfide, dibenzoyl disulfide, diacetyl disulfide, dibornyl disulfide dimethoxyxanthogen disulfide, Examples thereof include tetramethylthiuram monosulfide, tetramethylthiuram tetrasulfide, benzyldimethyldithiocarbamate quinoxaline, 1,3-dioxolane and N-laurylpyridinium.

From these, those having absorption in the wavelength region of the light source used in the manufacturing process and dissolved or dispersed in the solvent used for preparing the dope may be appropriately selected.
Usually, a solvent that dissolves in the solvent used is preferable because of high reaction efficiency.

The photocationic polymerization initiator used in the present invention includes aromatic diazonium salts, aromatic iodonium salts, aromatic sulfonium salts and the like. When using this initiator, an epoxy group can also be used in combination as a crosslinking reaction species.
In this case, the aforementioned epoxy group-containing compound may be used as a crosslinking agent or a hydrophilic binder polymer, or an epoxy group may be introduced into the hydrophilic binder polymer. When three-dimensional crosslinking is carried out by a photodimerization reaction, various sensitizers generally well known for the reaction such as 2-nitrofluorene and 5-nitroacenaphthene can be used. In addition to the above, Katsumi Tokumaru et al., "Sensitizer", Chapters 2 and 4, Kodansha (1987), Kiyomi Kato, "Ultraviolet Curing System", Comprehensive Technology Center, pp. 62-147 (1989), Fine Chemicals, Vol. 20 No4, 16 (199
Known polymerization initiators described in 1) can also be used.

The addition amount of the above-mentioned polymerization initiator can be used within the range of 0.01% to 20% by weight based on the active ingredient excluding the solvent in the dope. If the amount is less than 0.01% by weight, the effect of the initiator will not be exhibited, and if it is more than 20% by weight, the self-absorption of the actinic ray by the initiator will prevent the light from reaching the inside and the desired printing durability will be exhibited. You may not be able to do it. Practically, it is preferable to determine in the range of 0.1 to 10% by weight depending on the composition, by the balance between the effect of the initiator and the background stain on the non-image area.

As the irradiation light source, known ones such as a metal halide lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp and a chemical lamp can be used. When the heat from the irradiation light source may destroy the capsule, it is necessary to irradiate while cooling.

Known thermal polymerization initiators used in the present invention include benzoyl peroxide, 2,2-azobisisobutylnitrile, peroxides such as persulfate-sodium hydrogen sulfite, azo compounds, and redox initiators. Things can be used. In use, the reaction must be carried out at a temperature lower than the temperature at which the microcapsules are destroyed. The amount of the thermal polymerization initiator used is based on the components excluding the dope solvent.
The range of 0.01 to 10% by weight is preferable. If it is less than 0.01% by weight, the curing time becomes too long, and if it is more than 10% by weight, gelation may occur due to decomposition of the thermal polymerization initiator generated during the dope preparation. Considering the effect and handleability, it is preferably 0.1 to 5% by weight.

The hydrophilic binder polymer of the present invention must have a functional group that chemically bonds with the lipophilic component in the microcapsules. High printing durability can be obtained by chemically bonding the both. In order to react the lipophilic component in the microcapsule with the three-dimensionally cross-linked hydrophilic binder polymer, a monomer having a functional group which reacts with the reactive functional group of the lipophilic component described below is used to make the hydrophilic property. The target functional group may be introduced into the polymer by synthesizing the binder polymer, or may be introduced after synthesizing the polymer.

The reaction between the hydrophilic binder polymer and the lipophilic component is a reaction with a fast reaction rate, for example, urethanization between the hydrophilic binder polymer having a hydroxyl group or a carboxyl group or an amino group and the lipophilic component having an isocyanate group. Reaction, or ureation reaction, hydroxyl group,
Reaction of a hydrophilic binder polymer having a carboxyl group or an amino group with a hydrophilic component having an epoxy group,
Alternatively, an addition polymerization reaction of unsaturated groups is preferable. It may be a ring-opening addition reaction between a hydrophilic binder polymer having an acid anhydride group and a lipophilic component having a hydroxyl group, an amino group or an imino group, or an addition reaction between an unsaturated group and a thiol. In order to improve printing durability, it is preferable that the chemical bond has a three-dimensional crosslinked structure.

The lipophilic component of the present invention has a functional group that reacts with the hydrophilic binder polymer, appears outside the capsule by thermal printing, and rapidly reacts with the hydrophilic binder polymer to receive the chemically bonded ink. The image area is formed. In order to improve printing durability, it is preferable that the lipophilic component itself also has a crosslinked structure.

Examples of the lipophilic component of the present invention include phenyl isocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 3,3'-dimethylbiphenyl-4, 4'-diisocyanate, 1,5-naphthalene diisocyanate, tolidine diisocyanate, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, lysine diisocyanate, triphenylmethane triisocyanate, bicycloheptane triisocyanate, tridene diisocyanate, Isocyanates such as polymethylene polyphenyl isocyanate and polymeric polyisocyanate; trimethylolpropane and 1,6-hexane diisocyanate There is a pair of the above diisocyanates such as 2,4-tolylene diisocyanate 3
Polyisocyanates such as molar adducts,

Isocyanate compounds such as oligomers or polymers of 2-isocyanatoethyl (meth) acrylate; N, N'-methylenebisacrylamide, (meth) acryloylmorpholine, vinylpyridine, N-methyl (meth) acrylamide, N, N '-Dimethyl (meth) acrylamide, N, N'-dimethylaminopropyl (meth) acrylamide, N, N'-dimethylaminoethyl (meth) acrylate, N, N'-diethylaminoethyl (meth) acrylate, N, N' -Dimethylamino neopentyl (meth) acrylate, N-vinyl-
2 pyrrolidone, diacetone acrylamide, N-methylol (meth) acryl amide, parastyrene sulfonic acid or its salt,

Methoxytriethylene glycol (meth)
Acrylate, methoxytetraethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate (PEG number average molecular weight 40
0), methoxy polyethylene glycol (meth) acrylate (PEG number average molecular weight 1000), butoxyethyl (meth) acrylate, phenoxyethyl (meth).
Acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxyethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, nonylphenoxyethyl (meth) acrylate, dimethyloltricyclodecane di (meth) acrylate, diethylene glycol di (meth) acrylate , Tetraethylene glycol di (meth) acrylate,

Polyethylene glycol di (meth) acrylate (PEG number average molecular weight 400), polyethylene glycol di (meth) acrylate (PEG number average molecular weight 600), polyethylene glycol di (meth) acrylate (PEG number average molecular weight 1000) , Polypropylene glycol di (meth) acrylate (PPG number average molecular weight 400), 2,2-bis [4- (methacryloxyethoxy) phenyl] propane, 2,2-bis [4-
(Methacryloxy-diethoxy) phenyl] propane,
2,2-bis [4- (methacryloxy-polyethoxy)
Phenyl] propane or its acrylate, β-
(Meth) acryloyloxyethyl hydrogen phthalate, β- (meth) acryloyloxyethyl hydrogen succinate, polyethylene or polypropylene glycol mono (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate,

1,3-butylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri ( (Meth) acrylate, tetramethylolmethanetetra (meth) acrylate, isobornyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate,
Stearyl (meth) acrylate, isodecyl (meth)
Acrylate, cyclohexyl (meth) acrylate,
Tetrafurfuryl (meth) acrylate, benzyl (meth) acrylate, mono (2-acryloyloxyethyl) acid phosphate or its methacrylic compound, glycerin mono- or di (meth) acrylate, tris (2-acryloxyethyl) isocyanurate or its Methacrylic compounds, polyfunctional (meth) acrylic monomers such as 2-isocyanatoethyl (meth) acrylate or combinations of these with monofunctional (meth) acrylates,

Further, a combination with the above-mentioned (meth) acrylate monomer containing a hydrophilic group; N-phenylmaleimide, N- (meth) acryloxysuccinimide, N-vinylcarbazole, divinylethyleneurea,
A polyfunctional allyl compound such as divinylpropyleneurea or triallyl isocyanurate or a combination of these with a monofunctional allyl compound; further, a hydroxyl group, a carboxyl group,
Liquid rubbers containing 1,2-polybutadiene, 1,4-polybutadiene, water-added 1,2-polybutadiene, isoprene, etc. containing reactive groups such as amino groups, vinyl groups, thiol groups and epoxy groups at both ends of the polymer molecule; Various telechelic polymers such as urethane (meth) acrylate;
Reactive wax containing carbon-carbon unsaturated group, hydroxyl group, carboxyl group, amino group, epoxy group; propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, trimethylol Polyfunctional epoxy compounds such as propane triglycidyl ether and hydrogenated bisphenol A diglycidyl ether can be used.
Further, known (meth) acrylic copolymers, urethane acrylates, and diazo resins, which have been used as image components of existing PS plates before crosslinking, can also be used.

The lipophilic component may be solid or liquid at room temperature. Examples of polyisocyanate compounds that are solid at room temperature include tridene diisocyanate, 4,4′-diphenylmethane diisocyanate, naphthalene diisocyanate, polymethylene polyphenyl isocyanate, and polymer polyisocyanate.

Utilizing the double bond reaction of the ethylene addition-polymerizable monomer and oligomer contained in the lipophilic component, the lipophilic component and the hydrophilic binder polymer are chemically reacted or the lipophilic component itself is reacted. In this case, the following thermal polymerization initiators can be used. It is preferable that the thermal polymerization initiator is stable even when stored at 50 ° C. or lower, and further preferable if it is stable at 60 ° C. or lower.

For example, methyl ethyl ketone peroxide, cyclohexanone peroxide, n-butyl 4,4-bis (t-butylperoxy) valerate,
1,1-bis (t-butylperoxy) cyclododecane, 2,2-bis (t-butylperoxy) butane, cumene hydroperoxide, p-menthane hydroperoxide, di-t-butylperoxide, t -Butyl cumyl peroxide, dicumyl peroxide,
t-butyl peroxylaurate, t-butyl peroxyisopropyl carbonate, t-hexyl peroxybenzoate, t-butyl peroxybenzoate, t
-Peroxides such as butyl peroxyacetate.

As a method of adding the thermal polymerization initiator, this may be microencapsulated and used in the form of capsule-in-capsule in the microcapsules of the lipophilic component,
It may be dispersed as it is in the hydrophilic layer. The curing of the lipophilic component can use not only the polymerization reaction but also the reaction at the time of chemical bonding between the lipophilic component and the hydrophilic binder polymer.

From the viewpoint of improving printing durability of the image area, the image area of the present invention preferably has a urethane or urea structure. Either the lipophilic component is converted into a urethane or urea structure by a thermal reaction by printing, or the urethane or urea structure is introduced into the segment of the lipophilic component or the hydrophilic binder polymer in advance.

The lipophilic component is encapsulated according to a known method described in, for example, "New Technology of Microencapsulation and Development and Application Examples of Its Use" edited by Management Education Center, Management Development Center, published by Management Development Center Publishing (1978). For example, at the interface between two liquids that do not dissolve in each other, polycondensation of the reactant that has been added to each liquid in advance, and an unnecessary polymer film is formed in both solvents. The in-situ method in which the reactant is supplied only from the inside or outside of the polymer to form a polymer wall around the core substance, the hydrophilic polymer is applied to the surface of the hydrophobic substance dispersed in the hydrophilic polymer solution. It can be carried out by a complex coacervate method of phase-separating to form a capsule membrane, a phase separation method from an organic solution system, or the like. Among them, the interfacial polymerization method and the in-situ method are preferable because they facilitate the encapsulation of a relatively large number of core substances. It may be encapsulated with a material different from the lipophilic component.

The encapsulation referred to in the present invention also includes a method in which a polyisocyanate compound which is solid at room temperature is made into fine powder and the surface of the fine particles is blocked with the blocking agent so that it cannot react with ambient active hydrogen at room temperature. Including. In any case, it is necessary that the lipophilic component inside the capsule is released to the outside of the capsule by the heat during printing, and the morphology of the initial capsule is destroyed. For example, the lipophilic component is released due to expansion, compression, melting, and chemical decomposition of the capsule wall, and the expansion of the wall material of the capsule reduces the density, and the lipophilic component is released through the wall material layer. There are cases where

The surface of the outer shell of the capsule is not particularly limited as long as the background of the non-image area does not occur when the microcapsules are printed in the hydrophilic layer.
It is preferably hydrophilic. The average size of microcapsules is 10 μm or less, and 5 μm on average for high-resolution applications.
m or less is preferable. If the ratio of the lipophilic component relative to the entire capsule is too low, the image forming efficiency will be reduced, so that the average of 0.
It is preferably at least 01 μm.

The amount of the microencapsulated lipophilic component used may be determined according to the printing durability required for each printing application. Usually, it is preferable to use the microcapsule / hydrophilic binder polymer weight ratio in the range of 1/20 to 10/1, and in the range of 1/15 to 5/1 from the viewpoint of sensitivity and printing durability. .

In the hydrophilic layer of the present invention, as other components, promotion of thermal destruction of capsules, promotion of reaction between lipophilic component and a reactant having a functional group which reacts with the component, lipophilic component and hydrophilic binder polymer A sensitizer can be further added for the purpose of accelerating the reaction with. Addition makes it possible to increase printing sensitivity, improve printing durability, and perform high-speed plate making. Examples of such sensitizers include auto-oxidizing substances such as nitrocellulose, substituted cyclopropane, and high strain compounds such as cubane.

A polymerization reaction catalyst of a lipophilic component can also be used as a sensitizer. For example, if the reaction of the lipophilic component is the reaction of an isocyanate group, a urethane-forming catalyst such as dibutyltin dilaurate, stannic chloride, an amine compound, etc., and if the ring-opening reaction of an epoxy group is a quaternary ammonium salt, etc. A ring catalyst can be exemplified. The sensitizer can be added at the time of preparing the dope, at the same time as being included in the microencapsulation of the lipophilic component, or at a position between the support and the hydrophilic layer together with the binder resin. The amount used may be determined from the viewpoints of the effect of the sensitizer used and the printing durability of the non-image area.

In the case of laser printing, a light-heat converting substance having an absorption band in the emission wavelength region of the laser used can be further used. Examples of such substances include, for example, Ken Matsuoka, “JOEM Handbook 2, Absorption Spectrum of Diodes for Diode Lasers,” Bushin Publishing (1990), CMC Editorial Department, “Development and Market Trends of 90's Functional Dyes” CMC ( 1990) Polymethine dyes (cyanine dyes), phthalocyanine dyes, dithiol metal complex salt dyes, naphthoquinones, anthraquinone dyes, triphenylmethane dyes, aminium, diimmonium dyes, azo described in Chapter 2, 2.3. There are dyes, pigments and dyes such as a system disperse dye, an indoaniline metal complex dye and an intermolecular CT dye.

Specifically, N- [4- [5- (4-dimethylamino-2-methylphenyl) -2,4-pentadienylidene] -3-methyl-2,5-cyclohexadiene-1 -Ylidene] -N, N-dimethylammonium acetate, N- [4- [5- (4-dimethylaminophenyl) -3-phenyl-2-pentene-4-yn-1-
Ylidene] -2,5-cyclohexadiene-1-ylidene] -N, N-dimethylammonium perchlorate, N, N-bis (4-dibutylaminophenyl) -N
-[4- [N, N-Bis (4-dibutylaminophenyl) amino] phenyl] -aminium hexafluoroantimonate, 5-amino-2,3-dicyano-8-
(4-ethoxyphenylamino) -1,4-naphthoquinone,

N'-cyano-N- (4-diethylamino-2-methylphenyl) -1,4-naphthoquinonediimine, 4,11-diamino-2- (3-methoxybutyl)
-1-oxo-3-thioxopyrrolo [3,4-b] anthracene-5,10-dione, 5,16 (5H, 16
H) -Diaza-2-butylamino-10,11-dithiadinaphtho [2,3-a: 2'3'-c] -naphthalene-
1,4-dione, bis (dichlorobenzene-1,2-dithiol) nickel (2: 1) tetrabutylammonium, tetrachlorophthalocyanine aluminum chloride, polyvinylcarbazole-2,3-dicyano-5
Examples thereof include -nitro-1,4-naphthoquinone complex.

For the purpose of promoting the thermal destruction of the microcapsules, a substance which easily vaporizes or expands in volume when heated together with the lipophilic component can be included in the capsule together with the lipophilic component. For example, cyclohexane, diisopropyl ether, ethyl acetate, ethyl methyl ketone, tetrahydrofuran, t-butanol, isopropanol, 1,1,1-trichloroethane having a boiling point sufficiently higher than room temperature, a hydrocarbon around 60 to 100 ° C., a halogenated compound. There are hydrocarbon, alcohol, ether, ester and ketone compounds.

It is preferable to use a known heat-sensitive dye that develops color only in the printed area in combination with a lipophilic component so that the printed area can be visualized because the plate inspection is easy. For example, 3-diethylamino-
Examples include combinations of 6-methyl-7-anilinofluorane and leuco dyes such as bisphenol A and ground developer. Shin Okawara et al. "Dye Handbook" Kodansha (1
The heat-sensitive dyes disclosed in the publications such as 986) can be used.

In addition to the hydrophilic binder polymer, a reactive substance having a functional group that reacts with the lipophilic component can be used in order to increase the degree of crosslinking of the lipophilic component. The addition amount is an amount that does not cause scumming depending on the degree of ink repellency and hydrophilicity of the hydrophilic binder polymer. Examples of such reactive substances include compounds having a plurality of hydroxyl groups, amino groups, and carboxyl groups, such as polyvinyl alcohol, polyamine, polyacrylic acid, and trimethylolpropane, if the crosslinking reaction of the lipophilic component produces urethane. For the purpose of adjusting hydrophilicity, a hydrophilic binder polymer used and a non-reactive hydrophilic polymer that does not react with the lipophilic component may be added to the hydrophilic layer within a range that does not impair the printing durability.

In the case of printing with a thermal head, calcium carbonate, silica, zinc oxide, titanium oxide, kaolin, calcined kaolin, etc. are used as an absorbent of the melt for the purpose of preventing the melt generated by heating from adhering to the thermal head.
Known compounds such as hydrolyzed halloysite, alumina sol, diatomaceous earth, and talc can be added. Furthermore, it also improves the slipperiness of the plates and prevents the plates from sticking to each other.
A small amount of normal temperature solid lubricants such as stearic acid, myristic acid, dilauryl thiodipropionate, stearic acid amide, and zinc stearate can be added to the hydrophilic layer.

The support used in the present invention may be selected from known materials in consideration of the performance and cost required in the printing field. When high dimensional accuracy such as multicolor printing is required, and when it is used in a printing machine in which the mounting method on the plate cylinder is completed in accordance with the metal support, a metal support made of aluminum, steel or the like is preferable. When high printing durability is required without multicolor printing, a plastic support such as polyester can be used, and in the field where low cost is required, paper, synthetic paper, waterproof resin laminate or coated paper support can be used. In order to improve the adhesiveness between the support and the material in contact therewith, the support itself may be surface-treated. Examples of such surface treatments include various polishing treatments and anodic oxidation treatments for aluminum sheets, and corona discharge treatments and blast treatments for plastic sheets.

If necessary, such as printing durability, an adhesive layer can be provided on the support. Generally, when high printing durability is required, an adhesive layer is provided. The adhesive must be selected and designed according to the hydrophilic layer component and the support used. Acrylic, Urethane, Cellulose, Epoxy, etc. described in "Encyclopedia of Adhesion and Adhesion", published by Asakura Shoten (1986) by Shozaburo Yamada, "Adhesion Handbook", edited by Japan Adhesion Association, published by Nihon Kogyo Shimbun (1980), etc. Adhesives can be used.

The heat-sensitive lithographic printing plate precursor of the present invention can be manufactured by the following method. The above components are well dispersed with a solvent selected according to the crosslinking method of the hydrophilic binder polymer, a paint shaker, a ball mill, an ultrasonic homogenizer, etc., and the obtained coating liquid (dope) is a doctor blade method, a bar coating method, A heat-sensitive lithographic printing material is obtained by coating on a support and drying by a known method such as a roll coating method.

As the solvent, water, alcohols such as ethanol, isopropanol and n-butanol, ketones such as acetone and methyl ethyl ketone, ethers such as diethylene glycol diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, diethylene glycol, ethyl acetate and butyl acetate. And the like, aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as n-hexane and decalin, dimethylformamide, dimethylsulfoxide, acetonitrile, or a mixed solvent thereof can be used.

Further, if necessary, additional heating or ultraviolet irradiation is performed at a temperature lower than the temperature at which the microcapsules are destroyed in order to three-dimensionally crosslink the hydrophilic binder polymer.
The thickness of the coating film may be arbitrarily set between several μm and 100 μm. Usually, a thickness of 1 to 10 μm is preferable in terms of performance and cost. If it is necessary to enhance the surface smoothness, calendering may be performed after coating and drying or after the three-dimensional crosslinking reaction of the hydrophilic binder polymer. Especially when a high degree of smoothness is required, it is preferable to carry out after coating and drying.

In order to make the heat-sensitive lithographic printing plate precursor of the present invention, a document / image prepared / edited by an electronic typesetting machine, a DTP, a word processor, a personal computer or the like is simply drawn / printed by a thermal head or a heat mode laser. The development process is completed without any process. After printing, the crosslinking degree in the image area can be increased by heating (post cure) at a temperature at which the capsules are not destroyed or by irradiating the entire surface of the plate with actinic rays. When carrying out the latter method, the above-mentioned photopolymerization initiator or photocationic polymerization initiator in the hydrophilic layer and a compound having a functional group by which the reaction proceeds are used in combination or the functional group is introduced into a lipophilic component. It is necessary. The initiator and the compound having a functional group are not limited to the above-mentioned compounds. For example, “UV / EB curing handbook (raw material)” polymer by Kiyomi Kato, “Ultraviolet curing system”, Comprehensive Technology Center (1989), edited by Kiyomi Kato Known materials described in publications such as the publication society (1985) can be used.

The printing plate obtained as described above can be set in a commercially available offset printing machine and printed by a usual method. When printing, if necessary, the printing plate can be subjected to usual etching treatment before printing.

[0080]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. In the text, parts are parts by weight unless otherwise specified. Further, the average amount between crosslinks is shown as a calculated value on the assumption that the reaction has proceeded 100%.

Production Example of Hydrophilic Binder Polymer P-1 5.8 g of 2-hydroxyethyl acrylate, 16.2 g of acrylic acid, 16.0 g of acrylamide, 0.2 g of dodecyl mercaptan as a chain transfer agent, water / isopropyl alcohol (1 / (1 weight ratio) 100 g of the mixed solution was heated to 70 ° C. with stirring. 0.38 g of 2,2-azobis (isobutyronitrile) (hereinafter, AIBN) was added to this solution as a thermal polymerization initiator, and the reaction was carried out for 4 hours. Subsequently, 6.4 g of glycidyl methacrylate, 0.5 g of t-butylhydroquinone as a polymerization inhibitor and benzyltrimethylammonium chloride (hereinafter referred to as BTM
AC) (1 g) was added, and the mixture was reacted at 130 ° C for 6 hours. Then, acetone is added to precipitate the polymer, and the polymer is thoroughly washed and purified to obtain a hydrophilic binder polymer P-1 (number average molecular weight by GPC: 1.5 × 10 ⁴ , average molecular weight between crosslinks: 0.8).
× 10 ³ , water-kerosene-based oil-in-water method contact angle: 160
Got more than °).

Production Example of Hydrophilic Binder Polymer P-2 2-hydroxyethyl acrylate 5.8 g, acrylic acid 16.2 g, acrylamide 16.0 g, dodecyl mercaptan 0.2 g, isopropyl alcohol / toluene (1/1 weight ratio). 100 g of the mixed solution was heated to 70 ° C. with stirring. 0.3 g of AIBN was added to this solution, and the mixture was reacted for 4 hours. Then, acetone is added to precipitate the polymer, which is thoroughly washed and purified to obtain hydrophilic binder polymer P-2 (number average molecular weight by GPC: 1.7 × 10 ⁴ ,
Water-kerosene oil-in-water method contact angle: 160 ° or more) was obtained.

Production Example of Hydrophilic Binder Polymer P-3 52.2 g of 2-hydroxyethyl acrylate, 35.5 g of acrylamide, 3.6 g of acrylic acid, 0.9 g of dodecyl mercaptan, water / isopropyl alcohol (1
(1 / weight ratio) 100 g of the mixed solution was heated to 70 ° C. in the reactor. AIBN (1 g) was added thereto and reacted for 5 hours. Subsequently, 7.2 g of glycidyl methacrylate, t-
Butylhydroquinone (0.5 g) and BTMAC (1 g) were added, and the mixture was reacted at 130 ° C. for 6 hours. Then, acetone is added to precipitate and wash the polymer, and the hydrophilic binder polymer P-
3 (number average molecular weight by GPC: 1.5 × 10 ⁴ , average molecular weight between crosslinks: 1.8 × 10 ³ , oil-in-water contact angle of water-kerosene system: 160 ° or more) were obtained.

P-4 Production Example of Hydrophilic Binder Polymer 2-hydroxyethyl acrylate 58 g, acrylamide 35.5 g, dodecyl mercaptan 0.9, water 10
0 g of the mixed solution was heated to 70 ° C. in a reactor, to which A
1 g of IBN was added and reacted for 5 hours. Then, acetone is added to precipitate and wash the polymer for purification, and hydrophilic binder polymer P-4 (number average molecular weight by GPC: 1.
5 × 10 ⁴ , water-kerosene-based oil drop in water contact angle: 160
Got more than °).

Production Example of Hydrophilic Binder Polymer P-5: 33.8 g of acrylamide, 1.8 g of acrylic acid, 2-
11.6 g of hydroxy acrylate and 320 g of ethyl acetate / toluene (80/20 weight ratio) were dissolved. Nitrogen gas was introduced into the reaction solution, and the temperature was raised to 45 ° C with stirring,
After adding 0.41 g of AIBN dissolved in 20 g of the same mixed solvent, the mixture was reacted at 55 ° C. for 6 hours. The resulting slurry polymer was purified by repeating filtration and washing. Then, 20 g of the polymer was dissolved in 270 g of water, and the temperature was raised to 80 ° C. while introducing air. Polymerization inhibitor 2,6-tert-butyl paracresol (hereinafter, BHT) 0.4 g, trimethylbenzylammonium hydroxide (hereinafter, TMB) dissolved in isopropyl alcohol
AHO) 4.8 g, glycidyl methacrylate 16.2
and g were added and reacted for 4 hours until the acid value became zero.
This polymer is vacuum dried to obtain a hydrophilic binder polymer P.
-5 (number average molecular weight by GPC: 1.9 × 10 ⁵ , average molecular weight between crosslinks: 1.8 × 10 ³ , water-kerosene oil drop contact angle in water: 160 ° or more) was obtained.

Production Example of Hydrophilic Binder Polymer P-6 Polyoxyethylene glycol (number average molecular weight: 1 × 1
0 ³ ) and 100 g of 1,6-hexamethylene diisocyanate were stirred at 80 ° C. to synthesize a chain-extended polymer having isocyanate groups at both ends. Then, the temperature was raised to 85 ° C., dry air was introduced, and 32 g of glycerin monomethacrylate and 0.1 g of BHT were added. The hydrophilic binder polymer P- reacts until the isocyanate characteristic absorption is no longer recognized by an infrared spectrophotometer.
6 was obtained (number average molecular weight: 2.8 × 10 ³ , inter-crosslinking average molecular weight: 2.8 × 10 ³ , water-kerosene oil drop in water contact angle: 160 ° or more).

Production Example of Microencapsulated Lipophilic Component M-1 Coronate L desolventized into solid form (manufactured by Nippon Polyurethane, a 1: 3 mole addition product of trimethylolpropane and 2,4-tolylene diisocyanate) 10 g, 8 g of ethyl alcohol, 2 g of purified water, and a 5% aqueous solution of polyacrylamide were placed in a container and shaken with a paint shaker at room temperature for 1 hour to prepare microcapsules M-1 of isocyanate having the surface of fine particles blocked. The average size of the primary dispersed particles was 1.0 μm.

Production Example of Microencapsulated Lipophilic Component M-2 50 g of diglycidyl ether of bisphenol A was dissolved by heating and added to 200 g of a 5% acid-treated gelatin aqueous solution at 60 ° C. for emulsion dispersion. When the average size of the oil droplets reached 3 μm, 5% aqueous carboxymethyl cellulose solution (etherification degree: 0.6, average polymerization degree: 160) was added to adjust the pH.
After adjusting to 5.5, it was cooled to 10 ° C. 12 g of 10% formalin was added and the pH was adjusted to 10 with 10% caustic soda to obtain a microencapsulated lipophilic component M-2.

Production Example of Microencapsulated Lipophilic Component M-3: 3,3′-Dimethylbiphenyl-4,4′-diisocyanate 13.2 g, 2-hydroxyethyl acrylate 5.9 g and catalyst dibutyltin dilaurate 0.1. 05 g
Was dissolved in 80 g of ethyl acetate, stirred at 50 ° C. for 15 minutes, and then reacted at 70 ° C. for 2 hours to synthesize a compound having an acrylic group and an isocyanate group in the same molecule. After that, the solvent was distilled off and the residue was vacuum dried. The obtained solidified product was crushed in a mortar, and a 5% water / ethanol (5.5 / 2.5 weight ratio) solution of polyvinyl alcohol in approximately the same amount as the solidified product and an alumina ball were added thereto, and a paint shaker was added. A lipophilic component M-3 which was shaken for 1 hour, pulverized and microencapsulated was prepared. The average size of the primary dispersed particles was 0.9 μm.

Production Example of Microencapsulated Lipophilic Component M-4 Nonylphenol ethylene oxide adduct (HLB
15) 3 g, partially saponified polyvinyl alcohol 3 g, polyoxyethylene glycol (number average molecular weight: 2 × 1)
0 ³ ) 5 g was dissolved and dispersed in 150 g of water to prepare an emulsifier aqueous solution. Place this solution in the homogenizer and
5 g of trimethylolpropane triacrylate, 10 g of tetraethylene glycol dimethacrylate, 5 g of lauryl acrylate and 0.44 g of 1,6-hexamethylene diisocyanate, which had been mixed at 60 ° C. in advance, were added at 8,000 rpm. Stir for hours. In this way, a microencapsulated lipophilic component M-4 having an average particle size of 2.4 μm was obtained.

Example 1 On a 180 μm thick polyester support coated with a urethane adhesive, a dope of the following composition, which had been well dispersed in a paint shaker at room temperature for 30 minutes and then defoamed, was coated with a blade coater. did. Hydrophilic binder polymer P-1 (15% solid content): 12.0 parts Microencapsulated lipophilic component M-1 (20% solid content): 6.0 parts AIBN: 1.0 part Calcium carbonate (absorbent ): 0.8 part Zinc stearate (lubricant): 0.5 part Water: 18.7 parts

Then, it was air-dried for 30 minutes, dried in a vacuum dryer at 30 ° C. for 3 hours, and then calendered to obtain a lithographic printing material. Further, this was dried at 40 ° C. for 4 hours in combination with reaction to obtain a lithographic printing original plate having an average coating thickness of 4.5 μm. This original plate was connected to an electronic typesetting machine, and a plate-making apparatus equipped with a thermal head (TPH-293R7 manufactured by Toshiba) was used to print the printed image and make the plate without developing it to obtain a printing plate. This plate is trimmed to a predetermined size and offset printing machine (HAMADA 611 manufactured by Hamada Printing Machinery Co., Ltd.)
It was mounted on XL, using a hard blanket, and printed on high-quality paper (the ink used is BSD offset ink).
New rubber black gold, with etch treatment, dampening water was diluted 50 times with water). Even after 20,000 copies, there were no background stains and the image area could be printed clearly. The paper reflection density of the non-image area before and after printing was measured by a reflection densitometer (DM400, manufactured by Dainippon Screen Mfg. Co., Ltd.), and the difference between the two was 0.01 or less.

Example 2 In the dope composition of Example 1, the hydrophilic binder polymer P-1 was changed to P-3, 2.0 parts of trimethylolpropane as a crosslinking agent, and 3-diethylamino-6- as a coloring agent. 2.0 parts of methyl-7-anilinofluorane (solid content 40%, average particle size 2.5 μm) and bisphenol A dispersion (solid content 30%, average particle size 2.5 μ)
m) In the same manner as in Example 1 except that 10.0 parts were added, a lithographic printing original plate having an average coating thickness of 3 μm was obtained, and plate making and printing were performed. The image portion of the printing plate made without any development after printing was colored black, and plate inspection was easy.
As a result of printing, even after 30,000 copies, clear printing was possible without scumming. The difference in the paper reflection density of the non-image area before and after printing is 0.0
It was 1 or less.

Example 3 A dope having the following composition was applied in the same manner as in Example 1 on an aluminum support which had been electropolished in place of the polyester support (average molecular weight between crosslinks of hydrophilic binder polymer: 2. 5 × 10 ³ ). After air-drying for 30 minutes, dry in a vacuum dryer at 30 ° C for 3 hours, then calendering
A lithographic printing material was obtained. Further, this was dried at 60 ° C. for 8 hours in combination with reaction to prepare a lithographic printing original plate having an average coating thickness of 2.5 μm, which was then subjected to plate making and printing in the same manner as in Example 1.

Hydrophilic binder polymer P-2 (20% solids): 12.5 parts Glycerol tris-anhydrotrimellitate: 0.2 parts Microencapsulated lipophilic component M-2 (20% solids) : 7.0 parts Hydrolyzed halloysite (absorbent): 1.0 part Stearic acid amide (lubricant): 1.0 part 3-diethylamino-6-methyl-7-anilinofluorane (solid content 40% average particle size 2 .5 μm): 2.0 parts Bisphenol A dispersion liquid (solid content 30%, average particle size 2.5 μm): 10.0 parts Water: 18.5 parts The printing plate obtained without the development step was examined for image areas. Printing was easy, and clear printed matter was obtained without scumming even after 10,000 copies. The difference in the paper reflection density of the non-image area before and after printing is 0.0
It was 1 or less.

Example 4 A dope having the following composition was coated on an electrolytically polished aluminum support using a blade coater (average molecular weight between crosslinks of hydrophilic binder polymer: 1.3 × 10 ³ ). 15% toluene solution of hydrophilic binder polymer P-4: 12.0 parts Hexamethylene diisocyanate derivative masked with sodium acid sulfite: 0.25 parts Microencapsulated lipophilic component M-1 (solid content 99%) : 1.2 parts Kaolin (absorbent): 5.0 parts Toluene: 18.0 parts

Then, it was air-dried for 30 minutes to obtain a lithographic printing material. This was dried in a vacuum dryer at 55 ° C. for 4 hours, and then calendered to obtain a lithographic printing original plate having an average coating thickness of 3 μm. When plate making and printing were carried out in the same manner as in Example 1, a printed matter with clear images was obtained without scumming even after 20,000 copies. The difference in the paper reflection density of the non-image area before and after printing is
It was 0.01 or less.

Example 5 A lithographic printing original plate having an average coating thickness of 3 μm was obtained in the same manner except that 0.5 part of nitrocellulose (nitrification degree: 1.8) was added as a sensitizer to the dope of Example 2. When plate making and printing were carried out in the same manner as in Example 2, a printed matter of the same level as in Example 2 was obtained with an applied energy of 70% as compared with Example 2. Before printing, the difference in paper reflection density of this non-image area is 0.01
It was below.

Example 6 γ-acryloxypropyltrimethoxysilane was applied to one side of an aluminum sheet having a thickness of 200 μm and degreased with alkali, and the support was cured at 50 ° C. for 1 hour, and a dope having the following composition was applied by a blade coater. . Hydrophilic binder polymer P-5 (15% solid content): 5.0 parts Microencapsulated lipophilic component M-3 (15% solid content): 25.0 parts (2-acryloyloxyethyl) (4-benzoyl) Benzyl) dimethyl ammonium bromide (photopolymerization initiator): 0.01 part KIP-103 (Mitsui Toatsu Chemicals, phthalocyanine dye): 0.03 part partially saponified polyvinyl alcohol (5% solid content): 10.0 Part water: 16.0 parts

Then, after air-drying for 30 minutes, it was dried at 40 ° C. for 3 hours to obtain a lithographic printing material. Further, this was irradiated with a chemical lamp at 6 J / cm ² to obtain a lithographic printing original plate having an average coating thickness of 4 μm. A printing image was thermally printed by a printing device equipped with a 1W semiconductor laser element, which was connected to an electronic typesetting device, and then the entire plate surface was irradiated with a high-pressure mercury lamp for 1 minute without a developing step to obtain a printing plate. Trim this plate,
When printed in the same manner as in Example 1, a clear printed matter was obtained without scumming even after 50,000 copies. The paper reflection density of the non-image area before and after printing was 0.01 or less.

Example 7 The support used in Example 6 was coated with a dope having the following composition by a blade coater. Hydrophilic binder polymer P-6 (15% solid content): 5.0 parts Microencapsulated lipophilic component M-1 (20% solid content): 20.0 parts (2-acryloyloxyethyl) (4- Benzoylbenzyl) dimethyl ammonium bromide (photopolymerization initiator): 0.01 part KIP-101 (Mitsui Toatsu Chemicals, anthraquinone dye): 0.01 part partially saponified polyvinyl alcohol (5% solid content): 10. 0 copy Water: 16.0 copy

Then, after air-drying for 30 minutes, it was dried in a vacuum dryer at 30 ° C. for 3 hours to obtain a lithographic printing original plate. further,
This was irradiated with a chemical lamp at 6 J / cm ² to obtain a lithographic printing original plate having an average coating thickness of 3.5 μm. A printing plate was obtained from this original plate by the printing apparatus of Example 6 without going through a developing process. When this plate was trimmed and printed as in Example 1, 2
Even if the number of copies exceeded 10,000, clear prints were obtained without scumming.
The reflection density of the paper in the non-image area before and after printing was 0.01 or less.

Example 8 A dope having the following composition prepared at 5 to 10 ° C. was quickly applied to a 200 μm-thick polyester film subjected to corona discharge treatment with a blade coater. Polyallylamine (hydrophilic binder polymer, manufactured by Nitto Boseki Co., Ltd., product PA A-H, 20% aqueous solution): 12.0 parts Polyethylene glycol diglycidyl ether (number of repeating oxyethylene groups: 23): 1.0 part Microcapsules Lipophilic component M-3 (15% solid content): 6.5 parts Microencapsulated lipophilic component M-4 (15% solid content): 3.0 parts Silica: 0.5 part 3-diethylamino- 6-Methyl-7-anilinofluorane (solid content 40%, average particle size 2.5 μm): 0.5 part Bisphenol A dispersion (solid content 30%, average particle size 2.5 μm): 0.5 part Water: 18.0 parts

Next, while gradually raising the degree of vacuum so that foaming does not occur, it is dried in a vacuum dryer at 20 ° C. for 3 hours and then at 40 ° C.
The reaction was repeated for 1 hour and dried. Then 10% HCl
After soaking in an aqueous solution, taking out and washing with water,
It was dried at ° C for 1 hour. Then, calendering was performed to obtain a lithographic printing original plate having an average coating thickness of 3 μm. When plate making and printing were carried out in the same manner as in Example 1, clear printing was possible without scumming even after 20,000 copies. The difference in paper reflection density between the non-image areas before and after printing was 0.01 or less. In addition, the water-kerosene oil-in-water method contact angle of a film obtained by crosslinking the polyamine with the diglycidyl ether on the support was 160.
It was over °.

Comparative Example 1 Instead of the lipophilic component M-1 microencapsulated in Example 1, an average particle size of 1.0 μm having no reactive group was used.
A dope having the same composition was prepared except that the same amount of the wax of m was added, and coating, plate making and printing were carried out in the same manner as in Example 1. As a result, the image area of the printed material began to fade from around 600 copies.

Comparative Example 2 Instead of the microencapsulated lipophilic component M-1,
Methyl methacrylate-styrene-diethylene glycol dimethacrylate microgel (average particle size 0.5μ
m, a reactive functional group-free type) was encapsulated with acidic gelatin by a coacervation method in the same amount except that the same amount of microcapsules was used to prepare a lithographic printing plate precursor in the same manner as in Example 1. It was prepared, and plate-making and printing were performed. As a result, the image area of the printed matter began to fade around 2,000 copies. When the printing was interrupted, the plate ink was carefully wiped off, and the scraped portion was observed by SEM, a dent equivalent to the capsule size was found. No such phenomenon was observed where there was no blur.

Comparative Example 3 A lithographic printing original plate was obtained by applying and drying a dope having the same composition as in Example 3 except that glycerol tris-anhydrotrimellitate was not used. When plate making and printing were carried out in the same manner as in Example 1, from 4 to 500 parts, the background was stained and part of the area corresponding to the non-image area of the plate began to peel.

[0108]

In the heat-sensitive lithographic printing plate precursor of the present invention, the hydrophilic binder polymer is three-dimensionally crosslinked, and the lipophilic component exposed from the microcapsules by printing is chemically bonded to the binder polymer. The image area is formed. Therefore, the lithographic printing plate thus obtained has a markedly excellent printing durability, and a printed image having a clear image without background stain can be obtained. As a result, it can be put to practical use not only as light printing mainly for in-house printing but also as a plate material for full-scale printing such as newspaper rotary printing and form printing. Further, in the heat-sensitive lithographic printing plate precursor of the present invention, since the lipophilic component is microencapsulated, it can be reacted with the lipophilic component and the hydrophilic binder polymer for the first time at the time of printing, and the background stain of the non-image area is considered. It is less necessary and has high storage stability.

The heat-sensitive lithographic printing original plate of the present invention has a high degree of freedom in designing the plate because each constituent part takes charge of its function. Further, the heat-sensitive lithographic printing plate precursor of the present invention, even when the thermal head printing of the contact printing method, the adhesion to the thermal head is suppressed to a minimum, the frequency of cleaning the thermal head during plate making is drastically reduced and plate making workability is improved. Greatly improved. The heat-sensitive lithographic printing plate precursor of the present invention does not require development in the plate-making process of the present invention because the non-image area is mainly formed of a three-dimensionally crosslinked hydrophilic polymer. Work efficiency and cost reduction can be achieved because work such as developer management and waste liquid treatment is not required. The plate-making device is also compact, and although the accuracy is required, the device price can be designed low.

Claims (24)

[Claims] 1. A heat-sensitive lithographic printing plate precursor comprising a hydrophilic layer containing a microencapsulated lipophilic component which is converted into an image area by heat and a hydrophilic binder polymer, and the hydrophilic layer. The binder polymer is three-dimensionally crosslinked, and has a functional group that chemically bonds with the lipophilic component in the microcapsule after destruction of the capsule, and the lipophilic component in the microcapsule contains the functional group after the destruction of the capsule. A heat-sensitive lithographic printing original plate having a functional group chemically bonded to a hydrophilic binder polymer. 2. The hydrophilic binder polymer is a poly (meth) acrylate type, polyoxyalkylene type, polyurethane type, epoxy ring-opening addition polymerization type, poly (meth) acrylic acid type, poly (meth) acrylamide type polyester type, Polyamide-based, polyamine-based, polyvinyl-based, polysaccharide-based, or composite-based thereof, etc., having a carboxyl group, a phosphoric acid group, a sulfonic acid group, an amino group or a salt thereof in a side chain, a hydroxyl group, an amide group, a polyoxyethylene group A polymer composed of one or more hydrophilic functional groups such as a carbon-carbon bond, a carbon atom or a carbon-carbon bond bonded with at least one hetero atom consisting of oxygen, nitrogen, sulfur and phosphorus. A polymer composed of or a carboxyl group, phosphoric acid group, sulfonic acid group, or amino group on its side chain The heat-sensitive lithographic printing plate precursor according to claim 1, which is a polymer containing at least one hydrophilic functional group consisting of a salt, a hydroxyl group, an amide group and a polyoxyethylene group. 3. The hydrophilic binder polymer comprises a hydroxyl group, a carboxyl group or an alkali metal salt thereof, an amino group or a hydrohalide salt thereof, a sulfonic acid group or an amine salt thereof, an alkali metal salt and an alkaline earth metal in the side chain. 2. The heat-sensitive lithographic printing plate precursor according to claim 1, which has repeating segments of any one of a salt and an amide group or a combination thereof. 4. The heat-sensitive lithographic printing plate precursor as claimed in claim 1, wherein the hydrophilic binder polymer has a polyoxyethylene group in the main chain segment. 5. The heat-sensitive lithographic printing plate precursor as claimed in claim 1, wherein the hydrophilic binder polymer has a urethane bond or a urea bond in a main chain segment or a side chain. 6. The hydrophilic binder polymer is 0.02.
The heat-sensitive lithographic printing original plate according to claim 1, which has a difference in reflection density between the non-image areas of the paper before and after printing. 7. The hydrophilic binder polymer is (meth)
Acrylic acid or its alkali metal salts and amine salts, itaconic acid or its alkali metal salts and amine salts, 2-hydroxyethyl (meth) acrylate,
(Meth) acrylamide, N-monomethylol (meth)
Acrylamide, N-dimethylol (meth) acrylamide, allylamine or its hydrohalide,
3-Vinyl propionic acid or its alkali metal salt and amine salt, vinyl sulfonic acid or its alkali metal salt and amine salt, 2-sulfoethyl (meth) acrylate, polyoxyethylene glycol mono (meth)
Carboxyl group, sulfonic acid group, phosphoric acid, amino group of acrylate, 2-acrylamido-2-methylpropanesulfonic acid, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, allylamine or its hydrohalide, etc. Alternatively, the heat-sensitive lithographic printing according to claim 1, which is composed of a hydrophilic homo- or copolymer synthesized by using at least one kind selected from hydrophilic monomers having hydrophilic groups such as salts, hydroxyl groups, amide groups and ether groups thereof. Original version. 8. The heat-sensitive lithographic printing plate precursor according to claim 1, wherein the hydrophilic binder polymer is composed of polyoxymethylene glycol or polyoxyethylene glycol. 9. The lipophilic component is an isocyanate compound,
A polyfunctional (meth) acrylic monomer or a combination thereof with a monofunctional (meth) acrylate or a hydrophilic group-containing (meth) acrylate monomer, a polyfunctional allyl compound or a combination thereof with a monofunctional (meth) acrylate compound, or (meth ) A combination with an acrylate compound, a telechelic polymer, a reactive wax containing a reactive group consisting of a carbon-carbon unsaturated bond group, a hydroxyl group, a carboxy group, an amino group and an epoxy group, a polyfunctional epoxy compound, a diazo resin. The heat-sensitive lithographic printing original plate according to claim 1, which is composed of at least one selected from the group consisting of, (meth) acrylic copolymers and urethane acrylates. 10. The heat-sensitive lithographic printing original plate according to claim 1, wherein the lipophilic component has a urethane or urea structure. 11. The heat-sensitive lithographic printing original plate according to claim 1, wherein the lipophilic component can have a crosslinked structure. 12. The lipophilic component has an average of 10 μm or less.
The heat-sensitive lithographic printing original plate according to claim 1, which is a microcapsule having a particle diameter of 01 μm or more. 13. The heat-sensitive lithographic printing original plate according to claim 1, wherein the lipophilic component is 1/20 to 10/1 (weight ratio) with respect to the hydrophilic binder polymer. 14. The chemical bond is a bond formed by addition polymerization of an unsaturated group, a urethane reaction or a urea reaction of an isocyanate group with active hydrogen, or a reaction of a carboxyl group, a hydroxyl group or an amino group with an epoxy group. Heat sensitive planographic printing original plate described. 15. The heat-sensitive lithographic printing plate precursor as claimed in claim 1, wherein the chemical bond has a three-dimensional crosslinked structure. 16. The heat-sensitive lithographic printing original plate according to claim 1, wherein the hydrophilic layer contains a reactive substance which chemically bonds to the lipophilic component. 17. The hydrophilic layer comprises calcium carbonate, silica,
The heat-sensitive lithographic printing plate precursor as claimed in claim 1, which contains at least one absorbent selected from zinc oxide, titanium oxide, kaolin, calcined kaolin, hydrohalosite, alumina sol, diatomaceous earth and talc. 18. The heat-sensitive lithographic printing plate precursor as claimed in claim 1, wherein the hydrophilic layer contains a lubricant which is solid at room temperature. 19. The heat-sensitive lithographic printing original plate according to claim 1, wherein the lipophilic component contains a heat-sensitive dye capable of developing color only in the printed portion. 20. The heat-sensitive lithographic printing original plate according to claim 1, further comprising an adhesive layer provided on the support. 21. A heat-sensitive lithographic printing material comprising a support and a hydrophilic layer containing a microencapsulated lipophilic component which is converted into an image area by heat and a hydrophilic binder polymer, and the hydrophilic binder. The polymer has a functional group capable of three-dimensional crosslinking and a functional group that chemically bonds with the lipophilic component in the microcapsule after the destruction of the capsule, and the lipophilic component in the microcapsule is hydrophilic after the destruction of the capsule. A heat-sensitive lithographic printing material having a functional group chemically bonded to a binder polymer. 22. A heat-sensitive lithographic printing original plate comprising a support and a hydrophilic layer containing a hydrophilic binder polymer and a microencapsulated lipophilic component which is converted into an image area by heat, and said hydrophilicity The binder polymer is three-dimensionally crosslinked, and has a functional group that chemically bonds with the lipophilic component in the microcapsule after the capsule is broken, and the lipophilic component in the microcapsule is a binder after the capsule is broken. A lithographic printing plate obtained by printing with a thermal recording means a heat-sensitive lithographic printing plate precursor having a functional group that chemically bonds to a polymer. 23. A heat-sensitive lithographic printing original plate comprising a hydrophilic layer containing a microencapsulated lipophilic component which is converted into an image area by heat and a hydrophilic binder polymer, and the support, The binder polymer is three-dimensionally cross-linked, and has a functional group that chemically bonds with the lipophilic component in the microcapsule after destruction of the capsule, and the lipophilic component in the microcapsule contains the functional group after the destruction of the capsule. A method for making a heat-sensitive lithographic printing plate precursor, in which a heat-sensitive lithographic printing plate precursor having a functional group chemically bonded to a hydrophilic binder polymer is printed by a thermal recording means. 24. The method of making a heat-sensitive lithographic printing plate precursor according to claim 23, wherein after printing, the entire surface of the plate is heated at a temperature lower than the breaking temperature of the microcapsules.