Photosensitive composition

Abstract: A photosensitive composition is described, wherein it comoprises a high-molecular compound having sulfonamide group to be insoluble in water, but soluble in an aqueous alkaline solution and a positive working photosensitive compound. The photosensitive composition is excellent in coatability and in developability when the composition is used for photosensitive lithographic printing plate.

Description: This invention relates to a photosensitive composition suitable for use in the production of lithographic plates, IC circuits and photomasks and more particularly to a photosensitive composition comprising a positive working photosensitive compound and a high-molecular material excellent in wear resistance and chemical resistance. Photosensitive compositions comprising an o-naphthoquinone diazide compound and a novolak type phenolic resin have been industrially used as very superior photosensitive compositions in the field of photoresists or in the production of lithographic plates. However, since the novolak type phenolic resins are used as main ingredient in such conventional photosensitive compositions, they have disadvantages in that adhesion to substrates is poor, films formed therefrom are brittle, their coatability is poor and wear resistance is low. Further, they have problems that chemical resistance is low and printing durability is insufficient when used as lithographic plates, and printing durability is extremely poor, particularly when UV ink (a greasy ink for lithographic offset printings which cures upon exposure to ultraviolet light) is used. As a method for improving these performances, a burning-in treatment (a heat treatment after exposure and development) is generally carried out. When the burning-in treatment is conducted, however, there is posed the problem that a low-molecular compound in a photosensitive layer is deposited from an image part on a non-image part and staining is liable to be caused during printing. Various high-molecular materials have been proposed as binders to solve the problem. For example, JP-B-52-41050 (the term "JP-B" as used herein means an "examined Japanese patent publication") discloses polyhydroxystyrene or hydroxystyrene copolymers. The film forming properties are certainly improved by these copolymer. However, the photosensitive composition has still disadvantages in that wear resistance and chemical resistance are poor. Further, JP-A-51-347ll (the term "JP-A" as used herein means as "unexamined published Japanese patent application) discloses the use of high-molecular compounds having a structural unit of an acrylic acid derivative in the molecule as binders. However, such high-molecular compounds have problems that the range of proper developing conditions is narrow and wear resistance is insufficient. EP-A-253219 discloses a positive-working imaging composition comprising a polymeric binder and a quinone sensitizer, wherein the binder may be a polysulfonamide. US-A-4335254 discloses polymerizable acryloyloxyarylenesulfonamides. It is the object of the present invention to provide a photosensitive composition which can be developed by an aqueous alkaline developing solution, has good adhesion to substrates, gives a flexible film and is excellent in solubility in organic solvents and which gives lithographic plates having high printing durability even when printing is conducted by using UV ink without carrying out any burning-in treatment. Said object is achieved by a photosensitive composition comprising a high-molecular compound having at least one sulfonamide group in its side chains insoluble in water, but soluble in an aqueous alkaline solution and a positive working o-naphthoquinone diazide compound, wherein said high-molecular compound is obtained by polymerizing a low-molecular compound selected from the group consisting of compounds represented by formula (I) to (V) wherein X¹ and X² each represent -0- or -NR⁷; R¹ and R⁴ each represent H or CH₃; R² and R⁵ each represent an alkylene group having from 1 to 12 carbon atoms, a cycloalkylene group having from 3 to 12 carbon atoms, an arylene group having from 6 to 12 carbon atoms or an aralkylene group having from 7 to 14 carbon atoms, each of which may have one or more substituent groups; R³ represents a hydrogen atom, an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R⁶ represents an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R⁷ represents a hydrogen atom, an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R⁸, R¹⁰ and R¹⁴ each represent a hydrogen atom, a halogen atom or a methyl group; R⁹ represents an alkylene group having from 1 to 12 carbon atoms, a cycloalkylene group having from 3 to 12 carbon atoms, an arylene group having from 6 to 12 carbon atoms or an aralkylene group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R¹¹ and R¹⁵ each represent a single bond, an alkylene group having from 1 to 12 carbon atoms, a cycloalkylene group having from 3 to 12 carbon atoms, an arylene group having from 6 to 12 carbon atoms or an aralkylene group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R¹² and R¹⁶ each represent an alkylene group having from 1 to 12 carbon atoms, a cycloalkylene group having from 3 to 12 carbon atoms, an arylene group having from 6 to 12 carbon atoms or an aralkylene group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R¹³ represents a hydrogen atom, an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R¹⁷ represents an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; the above mentioned substituents being selected from an alkoxy group having from 1 to 6 carbon atoms, an alkanoyl group having from 1 to 6 carbon atoms, an alkanoyloxy group having from 1 to 6 carbon atoms, an alkoxycarbonyl group having from 1 to 6 carbon atoms, an N-alkylcarbamoyl group having from 1 to 6 carbon atoms, a halogen atom or a cyano group or, in the case of an arylene, aralkylene, aryl or aralkyl group, the above mentioned substituents being additionally selected from an alkyl group having from 1 to 6 carbon atoms; and Y¹ and Y² represent a single bond or The water-insoluble, aqueous alkaline solution-soluble high-molecular compound,has at least one -SO₂-NH- linkage in its side chain and is obtained by polymerizing a low-molecular compound selected from compounds of formula (I) to (V), in the presence of a conventional polymerization initiator in an appropriate solvent. Among the low-molecular compounds represented by the formulas (I)₂ and (II), there are preferred compounds wherein X¹ and X² each represent -NH-, R¹ and R⁴ each represent H or CH₃; R² and R⁵ represent each an alkylene group having from 2 to 6 carbon atoms, a cycloalkylene group having 5 or 6 carbon atoms or an optionally substituted phenylene group or naphthylene group (which may be substituted by an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms or a halogen atom); R³ is H, an alkyl group having from 1 to 6 carbon atoms, a cycloalkyl group having 5 or 6 carbon atoms, or an optionally substituted phenyl group or naphthyl group (which may be substituted by an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms or a halogen atom); R⁶ is an alkyl group having from 1 to 6 carbon atoms, a cycloalkyl group having 5 or 6 carbon atoms or an optionally substituted phenyl group or naphthyl group (which may be substituted by an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms or a halogen atom), The preferable low-molecular compounds include aminosulfonylphenyl methacrylamide, aminosulfonylphenyl acrylamide, suldonylphenyl, methacrylamide, sulfonylaminophenyl acrylamide, aminosulfonylphenyl methacrylate, aminosulfonylphenyl acrylate, sulfonylaminophenyl methacrylate, sulfonylaminophenyl acrylate; aminosulfonylnaphthyl methacrylamide, aminosulfonylnaphthyl acrylamide, sulfonylaminonaphthyl methacrylamide, sulfonylaminonaphthyl acrylamide, aminosulfonylnaphthyl methacrylate, aminosulfonylnaphthyl acrylate, sulfonylaminonaphthyl methacrylate, sulfonylaminonaphthyl acrylate; sminosulfonylethyl methacrylamide, aminosulfonylethyl acrylamide , sulfonylaminoethyl methacrylamide, sulfonylamionethyl acrylamide; aminosulfonylethyl methacrylate, aminosulfonylethyl acrylate, sulfonylaminoethylmethacrylate and sulfonylamionethyl acrylate. Typical examples of the low-molecular compounds include methacrylamides such as N-(o-amino-sulfonylphenyl)methacrylamide, N-(m-aminosulfonylphenyl)methacrylamide, N-(p-aminosulfonylphenyl)methacrylamide, N-(o-methylaminosulfonylphenyl)methacrylamide, N-(m-methylaminosulfonylphenyl)methacrylamide, N-(p-methylaminosulfonylphenyl)methacrylamide, N-(o-ethylaminosulfonylphenyl)methacrylamide, N-(m-ethylaminosulfonylphenyl)methacrylamide, N-(p-ethylaminosulfonylphenyl)methacrylamide, N-(o-n-propylaminosulfonylphenyl)methacrylamide, N-(m-n-propylaminosulfonylphenyl)methacrylamide, N-(p-n-propylaminosulfonylphenyl)methacrylamide, N-(o-isopropylaminosulfonylphenyl)methacrylamide, N-(m-isopropylaminosulfonylphenyl)methacrylamide, N-(p-isopropylaminosulfonylphenyl)methacrylamide, N-(o-n-butylaminosulfonylphenyl)methacrylamide, N-(m-n-butylaminosulfonylphenyl)methacrylamide, N-(p-n-butylaminosulfonylphenyl)methacrylamide, N-(o-isobutylaminosulfonylphenyl)methacrylamide, N-(m-isobutylaminosulfonylphenyl)methacrylamide, N-(p-isobutylaminosulfonylphenyl)methacrylamide, N-(o-sec-butylaminosulfonylphenyl)methacrylamide, N-(m-sec-butylaminosulfonylphenyl)methacrylamide, N-(p-sec-butylaminosulfonylphenyl)methacrylamide, N-(o-t-butylaminosulfonylphenyl)methacrylamide, N-(m-t-butylaminosulfonylphenyl)methacrylamide, N-(p-t-butylaminosulfonylphenyl)methacrylamide, N-(o-phenylaminosulfonylphenyl)methacrylamide, N-(m-phenylaminosulfonylphenyl)methacrylamide, N-(p-phenylaminosulfonylphenyl)methacrylamide, N-(o-(α-naphthylaminosulfonyl)phenyl)methacrylamide, N-(m-(α-naphthylaminosulfonyl)phenyl)methacrylamide, N-(p-(α-naphthylaminosulfonyl)phenyl)methacrylamide, N-(o-(β-naphthylaminosulfonyl)phenyl)methacrylamide, N-(m-(β-naphthylaminosulfonyl)phenyl)methacrylamide, N-(p-(β-naphthylaminosulfonyl)phenyl)methacrylamide, N-(1-(3-aminosulfonyl)naphthyl)methacrylamide, N-(1-(3-methylaminosulfonyl)naphthyl)methacrylamide, N-(1-(3-ethylaminosulfonyl)naphthyl)methacrylamide, N-(o-methylsulfonylaminophenyl)methacrylamide, N-(m-methylsulfonylaminophenyl)methacrylamide, N-(p-methylsulfonylaminophenyl)methacrylamide, N-(o-ethylsulfonylaminophenyl)methacrylamide, N-(m-ethylsulfonylaminophenyl)methacrylamide, N-(p-ethylsulfonylaminophenyl)methacrylamide, N-(o-phenylsulfonylaminophenyl)methacrylamide, N-(m-phenylsulfonylaminophenyl)methacrylamide, N-(p-phenylsulfonylaminophenyl)methacrylamide, N-(o-(p-methylphenylsulfonylamino)phenyl)methacrylamide, N-(m-(p-methylphenylsulfonylamino)phenyl)methacrylamide, N-(p-(p-methylphenylsulfonylamino)phenyl)methacrylamide, N-(p-(α-naphthylsulfonylamino)phenyl)methacrylamide, N-(p-(β-naphthylsulfonylamino)phenyl)methacrylamide, N-(2-methylsulfonylaminoethyl)methacrylamide, N-(2-ethylsulfonylaminoethyl)methacrylamide, N-(2-phenylsulfonylaminoethyl)methacrylamide, N-(2-p-methylphenylsulfonylaminoethyl)methacrylamide, N-(2-α-naphthylsulfonylaminoethyl)methacrylamide, N-(2-β-naphthylsulfonylaminoethyl)methacrylamide; acrylamides having substituent groups corresponding to those of the above-described methacrylamides ; methacrylates such as o-aminosulfonylphenyl methacrylate, m-aminosulfonylphenyl methacrylate, p-aminosulfonylphenyl methacrylate, o-methylaminosulfonylphenyl methacrylate, m-methylaminosulfonylphenyl methacrylate, p-methylaminosulfonylphenyl methacrylate, o-ethylaminosulfonylphenyl methacrylate, m-ethylaminosulfonylphenyl methacrylate, p-ethylaminosulfonylphenyl methacrylate, o-n-propylaminosulfonylphenyl methacrylate, m-n-propylaminosulfonylphenyl methacrylate, p-n-propylaminosulfonylphenyl methacrylate, o-isopropylaminosulfonylphenyl methacrylate, m-isopropylaminosulfonylphenyl methacrylate, u-n-butylaminosulfonylphenyl methacrylate, m-n-butylaminosulfonylphenyl methacrylate, p-n-butylaminosulfonylphenyl methacrylate, m-isobutylaminosulfonylphenyl methacrylate, p-isobutylaminosulfonylphenyl methacrylate, m-sec-butylaminosulfonylphenyl methacrylate, p-sec-butylaminosulfonylphenyl methacrylate, m-t-butylaminosulfonylphenyl methacrylate, p-t-butylaminosulfonylphenyl methacrylate, o-phenylaminosulfonylphenyl methacrylate, m-phenylaminosulfonylphenyl methacrylate, p-phenylaminosulfonylphenyl methacrylate, m-(α-naphthylaminosulfonyl)phenyl methacrylate, p-(α-naphthylaminosulfonyl)phenyl methacrylate, m-(β-naphthylaminosulfonyl)phenyl methacrylate, p-(β-naphthylaminosulfonyl)phenyl methacrylate, 1-(3-aminosulfonyl)naphthyl methacrylamide, 1-(3-methylaminosulfonyl)naphthyl methacrylamide, 1-(3-ethylaminosulfonyl)naphthyl methacrylamide, o-methylsulfonylaminophenyl methacrylate, m-methylsulfonylaminophenyl methacrylate, p-methylsulfonylaminophenyl methacrylate, o-ethylsulfonylaminophenyl methacrylate, m-ethylsulfonylaminophenyl methacrylate, p-ethylsulfonylaminophenyl methacrylate, o-phenylsulfonylaminophenyl methacrylate, m-phenylsulfonylaminophenyl methacrylate, p-phenylsulfonylaminophenyl methacrylate, o-(p-methylphenylsulfonylamino)phenyl methacrylate, m-(p-methylphenylsulfonylamino)phenyl methacrylate, p-(p-methylphenylsulfonylamino)phenyl methacrylate, p-(α-naphthylsulfonylamino)phenyl methacrylate, p-(β-naphthylsulfonylamino)phenyl methacrylate, 2-methylsulfonylaminoethyl methacrylate, 2-ethylsulfonylaminoethyl methacrylate, 2-phenylsulfonylaminoethyl methacrylate, 2-p-methylphenylsulfonylaminoethyl methacrylate, 2-α-naphthylsulfonylaminoethyl methacrylate and 2-β-naphthylsulfonylaminoethyl methacrylate; and acrylates having substituent groups corresponding to those of the above-described methacrylates. In formulae (III) to (V) R⁸, R¹⁰ and R¹⁴ each is preferably a hydrogen atom, R⁹ is preferably a methylene, phenylene or naphthylene group, each of which may have one or more substituent groups which are selected from the groups of an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms and a halogen atom, R¹¹ and R¹⁵ are preferably a simple bond or a methylene group, R¹² and R¹⁶ are preferably an alkylene group having from 1 to 6 carbon atoms, a phenylene group or a naphthylene group. The phenylene and naphthylene groups may be optionally substituted by an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms or a halogen atom. R¹³ is preferably a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms, a cycloalkyl group having 5 or 6 carbon atoms, a phenyl group or a naphthyl group. The phenyl and naphthyl groups may be optionally substituted by an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms or a halogen atom. R¹⁷ is preferably an alkyl group having from 1 to 6 carbon atoms, a cyclalkyl group having 5 or 6 carbon atoms, a phenyl group or a naphthyl group. The phenyl and naphthyl groups may be optionally substituted by an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms and a halogen atom. Examples of the compounds represented by the formulas (III) to (V) include p-aminosulfonylstyrene, p-aminosulfonyl-α-methylstyrene, p-aminosulfonylphenyl allyl ether, p-(N-methylaminosulfonyl)phenyl allyl ether, vinyl methylsulfonylaminoacetate, phenylsulfonylaminovinylacetate, methylsulfonylamino-allylacetate, phenylsulfonylaminc-allylacetate, phenylsulfonylamino-allylacetate and p-methylsulfonylaminophenyl allyl ether. The high-molecular ccmpound having a sulfonamide group which can be used in the present invention may be a homopolymer of the above-described low-molecular compound, or the high-molecular compound may be a copolymer of two or more of said low-molecular compounds. However, there is preferred a copolymer of said low-molecular compound with at least one compound having at least one polymerizable unsaturated bond and no sulfonamide group. Examples of such compounds having at least one polymerizable unsaturated bond and no sulfonamide group are compounds having a polymerizable unsaturated bond selected from the group consisting of acrylic acid, methacrylic acid, acrylates, acrylamides, methacrylates, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, styrenes and crotonates. Typical examples of such compounds include acrylates such as alkyl acrylates (the alkyl moiety thereof having preferably from 1 to 10 carbon atoms) (e.g., methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, ethylhexyl acrylate, octyl acrylate, t-octyl acrylate, chloroethyl acrylate, 2,2-dimethylhydroxypropyl acrylate, 5-hydroxypentyl acrylate, trimethylolpropane monoacrylate, pentaerythritol monoacrylate, glycidyl acrylate, benzyl acrylate, methoxybenzyl acrylate, furfuryl acrylate and tetrahydrofurfuryl acrylate) and aryl acrylates (e.g. phenyl acrylate); methacrylates such as alkyl methacrylates (the alkyl moiety thereof having preferably from 1 to 10 carbon atoms) (e.g., methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, chlorobenzyl methacrylate, octyl methacrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, glycidyl methacrylate, furfuryl methacrylate and tetrahydrofurfuryl methacrylate) and aryl methacrylates (e.g., phenyl methacrylate, cresyl methacrylate and naphthyl methacrylate); acrylamides such as acrylamide, N-alkylacrylamides (the alkylmoiety thereof having preferably from 1 to 10 carbon atoms, such as methyl, ethyl, propyl, butyl, t-butyl, heptyl, octyl, cyclohexyl, hydroxyethyl and benzyl), N-arylacrylamides (examples of the aryl group being phenyl, tolyl, nitrophenyl, naphthyl and hydroxyphenyl), N,N-dialkylacrylamides (the alkyl moiety thereof having preferably from 1 to 10 carbon atoms, such as methyl, ethyl, butyl, isobutyl, ethylhexyl and cyclohexyl), N,N-arylacrylamides (an example of the aryl group being phenyl), N-methyl-N-phenylacrylamide, N-hydroxyethyl-N-methylacrylamide and N-2-acetamidoethyl-N-acetylacrylamide; methacrylamides such as methacrylamide, N-alkylmethacrylamides (the alkyl moiety thereof having preferably from 1 to 10 carbon atoms, such as methyl, ethyl, t-butyl, ethylhexyl, hydroxyethyl and cyclohexyl), N-arylmethacrylamides (an example of the aryl group being phenyl), N,N-dialkylmethacrylamides (examples of the alkyl group being ethyl, propyl and butyl), N,N-diarylmethacrylamides (an example of the aryl group being phenyl), N-hydroxyethyl-N-methylmethacrylamide; N-methyl-N-phenylmethacrylamide and N-ethyl-N-phenylmethacrylamide; allyl compounds such as allyl esters (e.g., allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate and allyl lactate) and allyloxyethanol; vinyl ethers such as alkylvinyl ethers (e.g., hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethylhexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2,2-dimethylpropyl vinyl ether, 2-ethylbutyl vinyl ether, hydroxyethyl vinyl ether, diethylene glycol vinyl ether, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether and tetrahydrofurfuryl vinyl ether) and vinyl aryl ethers (e.g., vinyl phenyl ether, vinyl tolyl ether, vinyl chlorophenyl ether, vinyl 2,4-dichlorophenyl ether, vinyl naphthyl ether and vinyl anthranyl ether); vinyl esters such as vinyl butyrate, vinyl isobutyrate, vinyl trimethylacetate, vinyl diethylacetate, vinyl pivalate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxyacetate, vinyl butoxyacetate, vinyl phenylacetate, vinyl acetoacetate, vinyl lactate, vinyl β-phenylbutyrate, vinyl cyclohexylcarboxylate, vinyl benzoate, vinly salicylate, vinyl chlorobenzoate, vinyl tetrachlorobenzoate and vinyl naphthoate; styrenes such as styrene, alkylstyrenes (e.g., methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, isopropylstyrene, butylstyrene, hexylstyrene, cyclohexylstyrene, decylstyrene, benzylstyrene, chloromethylstyrene, trifluoromethylstyrene, ethoxymethylstyrene and acetoxymethylstyrene), alkoxystyrenes (e.g., methoxystyrene, 4-methoxy-3-methylstyrene and dimethoxystyrene) and halogenated styrenes (e.g., chlorostyrene, dichlorostyrene, trichlorostyrene, tetrachlorostyrene, pentachlorostyrene, bromostyrene, dibromostyrene, iodostyrene, fluorostyrene, trifluorostyrene, 2-bromo-4-trifluoromethylstyrene and 4-fluoro-3-trifluoromethylstyrene); crotonates such as alkyl crotonates (e.g., butyl crotonate, hexyl crotonate and glycerol monocrotonate); dialkyl itaconates (e.g., dimethyl itaconate, diethyl itaconate and dibutyl itaconate); dialkyl maleates or fumarates (e.g., dimethyl maleate and dibutyl fumarate); and acrylonitrile and methacrylonitrile. Among these compounds having a polymerizable unsaturated bond, there are preferred acrylates, methacrylates, methacrylamides, acrylamides, acrylonitrile, methacrylonitrile, methacrylic acid and acrylic acid. The copolymers of at least one member of these compounds having a polymerizable unsaturated bond with at least one member of the compounds having a sulfonamide group and a polymerizable unsaturated bond can be used in any form of block, random and graft copolymers. The amount of the structural unit having a sulfonamide group in the copolymer is preferably at least 5 mol %, more preferably 10 to 90 mol % based on the total amount of the structural units constituting the copolymer. Examples of solvents which can be used in the synthesis of these copolymers include ethylene dichloride, cyclohexanone, methyl ethyl ketone, acetone, methanol, ethanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, toluene, ethyl acetate, methyl lactate and ethyl lactate. These solvents may be used either alone or as a mixture of two or more of them. For the purpose of the present invention, it is desirable that the high-molecular compounds have a weight-average molecular weight of preferably 2,000 or higher, more preferably from 5,000 to 300,000 and a number-average molecular weight of preferably 1,000 or higher, more preferably from 2,000 to 250,000 and a polydisperse degree (weight-average molecular weight/number-average molecular weight) of preferably not lower than 1, more preferably from 1.1 to 10. Unreacted monomers mav be left behind in the high-molecular compounds used in the present invention. However, it is desirable that the content of the unreacted monomers in the high-molecular compounds is not more than 15% by weight. The high-molecular compounds of the present invention may be used either alone or as a mixture of two or more of then. The amount of the high-molecular compound to be incorporated into the photosensitive composition is from 5 to 95% by weight, preferably from 10 to 85% by weight. As positive working photosensitive compound o-naphthoquinone diazide compounds are used in the present invention. As the o-naphthoquinone diazide compounds which can be used in the present invention, esters derived from 1,2-diazonaphthoquinonesulfonic acid chloride and a pyrogallol-acetone resin disclosed in U.S.Patent 3,635,709 are preferred. Other suitable examples of o-quinone diazide compounds include esters derived from 1,2-diazonaphthoquinonesulfonic acid chloride and a phenol-formaldehyde resin disclosed in U.S. Patents 3,046,120 and 3,188,210. Other useful o-naphthoquinone diazide compounds have been reported in many patent specifications. For example, they are disclosed in JP-A-47-5303, JP-A-48-63802, JP-A-48-63803, JP-A-48-96575, JP-A-49-38701, JP-A-48-13354, JP-B-37-18015, JP-B-41-11222, JP-B-45-9610, JP-B-49-17481, U.S. Patents 2,797,213, 3,454,400, 3,544,323, 3,573,917, 3,674,495 and 3,785,825, U.K. Patents 1,227,602, 1,251,345, 1,267,005, 1,329,888 and 1,330,932 and German Patent 854,890. Particularly preferred o-naphthoquinone dizazide compounds which are used in the present invention are compounds obtained by the reaction of a polyhydroxy compound having a molecular weight of not higher than 1,000 with 1,2-diazonaphthoquinonesulfonic acid chloride. Specific examples of such compounds include those disclosed in JP-A-51-139402, JP-A-58-150948, JP-A-58-203434, JP-A-59-165053, JP-A-60-121445, JP-A-60-134235, JP-A-60-163043, JP-A-61-118744, JP-A-62-10645, JP-A-62-10646, JP-A-62-153950 and JP-A-62-178562, U.S. Patent Application Serial No. 245,190 filed September 16, 1988 or European Patent Application No. 88115250.8, and U.S. Patents 3,102,809, 3,126,281, 3,130,047, 3,148,983, 3,184,310, 3,188,210 and 4,639,406. In the synthesis of these o-naphthoquinone diazide compounds, it is preferred that 0.2 to 1.2 equivalent, particularly 0.3 to 1.0 equivalent of 1,2-diazonaphthoquinonesulfonic acid chloride per one equivalent of hydroxyl group in the polyhydroxy compound is reacted. The resulting o-naphthoquinone diazide compounds are in the form of a mixture composed of various amounts of compounds where the amounts of introduced 1,2-diazonaphthoquinonesulfonic ester group and the introduced positions thereof are different. It is preferred that the ratio of the compounds where all of the hydroxyl groups are converted by l,2-diazonaphthoquinonesulfonic ester (the content of the compounds which are fully esterified) is at least 5 mol %, particularly 20 to 99 mol %. The amount of the positive working photosentive compound in the photosensitive composition of the present invention is preferably from 10 to 50% by weight, more preferably from 15 to 40% by weight. In addition to the high-molecular compound having a sulfonamide group, the photosensitive composition of the present invention may optionally contain known alkali-soluble high-molecular compounds such as a phenol-formaldehyde resin, a cresol-formaldehyde resin (e.g., a m-cresol-formaldehyde resin, a p-cresol-formaldehyde resin, a m-/p-mixed cresol-formaldehyde resin or a phenol/cresol (m-, p- or m-/p-mixed) mixture-formaldehyde resin), a phenol-modified xylene resin, a poly hydroxystyrene and a polyhalogenated hydroxystyrene. For the purpose of the present invention, it is desirable that these alkali-soluble high-molecular compounds have a weight-average molecular weight of from 500 to 20,000 and a number-average molecular weight of from 200 to 60,000. The amount of the alkali-soluble high-molecular compound to be added is not more than 70% by weight based on the total amount of the composition. Further, it is preferred from the viewpoint of an improvement in ink-receptivity of image that there is used a condensate of a phenol having an alkyl group having from 3 to 8 carbon atoms as a substituent group with formaldehyde such as a t-butylphenol-formaldehyde resin or an octylphenol-formaldehyde resin disclosed in U.S. Patent 4,123,279. A cyclic acid anhydride for increasing sensitivity, a printing-out agent for obtaining a visible image immediately after exposure, a dye as an image coloring agent, another filler, etc. may be added to the composition of the present invention. Examples of the cyclic acid anhydride include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, 3,6-endoxy-Δ4-tetrahydrophthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride, α-phenylmaleic anhydride, succinic anhydride and pyromellitic anhydride disclosed in U.S. Patent 4,115,128 as well as those described in U.S. Patent 4,442,195. When 1 to 15% by weight (based on the amount of the composition) of the cyclic acid anhydride is incorporated in the composition, sensitivity can be increased about three times at maximum. As the printing-out agent for obtaining a visible image immediately after exposure, there can be used combinations of a photosensitive compound releasing an acid by exposure with an organic dye capable of forming a salt. Typical examples of the combinations include the combinations of an o-naphthoquinonediazido-4-sulfonic acid halogenide with a salt-forming organic dye disclosed in U.S. Patent 3,969,118 and the combinations of a trihalomethyl compound with a salt-forming organic dye disclosed in JP-A-53-36223, U.S. Patent 4,232,106, JP-A-60-3626, JP-A-61-143748, JP-A-61-151644 and EP-A-262788. As the image coloring agent, other dyes in addition to said salt-forming organic dyes can be used. Dyes suitable for use in the present invention include oil-soluble dyes and basic dyes including said salt-forming organic dyes. Typical examples of the dyes include Oil Yellow #101, Oil Yellow #130, Oil Pink #312, Oil Green BG, Oil Blue BOS, Oil Blue #603, Oil Black BY, Oil Black BS and Oil Black T505 (products of Orient Kagaku Kogyo KK) and Victoria Pure Blue, Crystal Violet (CI42555), Methyl Violet (CI42535), Rhodamine B (CI45170B), Malachite Green (CI142000) and Methylene Blue. Dyes described in GB-A-3192729 are particularly preferred. When the photosensitive composition of the present invention is used for a lithograihic plate, an addition of organic acid having a pKa of 3.0 or less, preferably 1.0 or less at 25°C to the photosensitive composition results in an increase of deletion-speed at areas having unwanted images using a deletion liquid which is disclosed in, for example, U.S. Patent 4,396,703. As the organic acids which can be used in the present invention, sulfonic acids, sulfinic acids, alkylsulfates, phosphonic acids, and phosphinic acids are preferred. Of them, sulfonic acids and sulfinic acids are more preferred. Typical examples of the organic acids include naphthalene-2-sulfonic acid, naphthalene-l-sulfonic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, mesitylenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, m-benzene-disulfonic acid, cyclohexylsulfamic acid, p-toluidine-2-sulfonic acid, pyridine-3-sulfonic acid, phenyl-J-acid (7-anilino-4-hydroxy-2-naphthalenesulfonic acid), p-toluene-sulfinic acid, benzylsulfinic acid, methanesulfinic acid, phenylphosphonic acid, methylphosphonic acid, chloromethylphosphonic acid, dimethylphosphinic acid, diphenylphosphate, diphenyl phosphite and ethyl sulfate. In addition, carboxylic acids and phenols having a small pKa value, such as trifluoroacetic acid, trichloroacetic acid, 2,6-dichlorobenzoic acid or picric acid, can be used in the present invention. The organic acid used in the present invention may have two or more functional groups providing acidic property per molecule, as long as the organic acid contains at least one functional group having a pKa of 3 or less in a molecule. Examples of the organic acids are shown below. The organic acids used in the present invention include also a compound which is not an organic acid before being incorporated into the photosensitive solution, but is decomposed in a photosensitive solution comprising a photosensitive composition dissolved in an organic solvent after being incorporated into the photosensitive solution, with a high decomposition speed, preferably 50% or more of decomposition ratio in 24 hours, to form an organic acid. As the organic acids, sulfonyl halide or sulfonate are preferably used. Examples of the organic acids are illustrated below. Sulfonyl halides described above are decomposed acceleratingly by using a protic polar solvent such as N,N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone or N,N-dimethylacetamide, as a part of coating solvent to form a sulfonic acid. Therefore, in many cases, sulfonic halides act in the same manner as sulfonic acid. The amount of the organic acid used in the present invention is preferably from 0.05 to 5 wt%, more preferably from 0.2 to 2 wt% based on the total weight of the photosensitive composition, and a mixture of organic acids may be used. The composition of the present invention is dissolved in an appropriate solvent capable of dissolving the above-described ingredients and the resulting solution is coated on a support. Typical examples of the solvent include ethylene dichloride, cyclohexanone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, dimethyl sulfoxide, dimethylacetamide, dimethylformamide, water, N-methyl-pyrrolidone, tetrahydrofurfuryl alcohol, acetone, diacetone aclohol, methanol, ethanol, isopropanol and diethylene glycol dimethyl ether. These solvents may be used either alone or as a mixture of two or more of them. The concentration, on a solid basis, of the composition is from 2 to 50% by weight. The amount to be coated varies depending on the use of the composition, but is preferably from 0.5 to 3.0 g/m² on a solid basis, with regard to photosensitive lithographic plates. With a decrease in the amount to be coated, photosensitivity is increased, but the physical properties of the photosensitive films are lowered. In order to improve coatability, a surfactant such as a fluorine-containing surfactant disclosed in EP-A-230995 may be added to the composition of the present invention. The amount of the surfactant to be added is preferably from 0.01 to 1% by weight, more preferably from 0.05 to 0.5% by weight based on the total amount of the photosensitive composition. When lithographic plates are prepared by using the photosensitive composition of the present invention, an aluminum sheet is preferred as a support. As the aluminum sheet, any of a pure aluminum sheet and an aluminum alloy sheet can be used. As the aluminum alloy, various alloys such as alloys of aluminum with silicon, copper, manganese, magnesium, chromium, zinc, lead, bismuth or nickel, can be used. These composition may contain neglectable amounts of impurities in addition to some iron and titanium. If desired, the surface of the aluminum sheet may be treated. For example, the surface treatment is preferably conducted by a graining treatment, an immersion treatment in an aqueous solution of sodium silicate, potassium fluorozirconate or a phosphate or an anodic oxidation treatment. Preferred examples of the aluminum sheet include an aluminum sheet obtained by graining an aluminum sheet and then immersing it in an aqueous solution of sodium silicate according to the method described in British Patent 851,819 and an aluminum sheet obtained by treating an aluminum sheet by anodic oxidation and then immersing it in an aqueous solution of an alkali metal silicate as described in U.S. Patent 3,181,461. The anodic oxidation treatment is carried out by using the aluminum sheet as an anode and allowing electric current to flow therethrough in an electrolytic solution composed of one or a combination of two or more of aqueous solutions or non-aqueous solutions of inorganic acids such as phosphoric acid, chromic acid, sulfuric acid or boric acid, or organic acids such as oxalic acid, sulfamic acid or salts thereof. Silicate electrodeposition disclosed in U.S. Patent 3,658,662 can be effectively used. These hydrophilization treatments are made for the purpose of preventing undesirable reactions of the support with the photosensitive composition provided thereon and of improving the adhesion of the support to the photosensitive layer in addition to making the surface of the support hydrophilic. If desired, pretreatments for removing rolling mill oil from the surface of the support and cleaning the surface thereof may be conducted prior to graining of the aluminum sheet. For the former, solvents such as trichloroethylene or surfactants, are used, while for the latter, there are widely carried out methods wherein alkali etching agents such as sodium hydroxide or potassium hydroxide, are used. As the graining method, any of mechanical, chemical and electrochemical methods is effective. Examples of the mechanical method include a ball polishing method, a blast polishing method and a brush polishing method wherein the surface of the support is rubbed with an aqueous slurry of an abrasive such as pumice by using a nylon brush. As the chemical method, there is preferred a method described in U.S. Patent 4,201,836 wherein the support is immersed in a saturated aqueous solution of an aluminum salt of a mineral acid. As the electrochemical method, there is preferred a method wherein AC electrolysis is carried out in an acidic electrolytic solution such as hydrochloric acid, nitric acid or a mixture thereof. Among these roughening methods, there is particularly preferred a roughening method composed of a combination of mechanical roughening with electrochemical roughening as disclosed in U.S. Patent 4,476,006, because the adhesion of the fat-sensitive image to the support is firmly. It is desirable that the above-described sand dressing methods are conducted to such an extent that the center line surface roughness (Ha) on the surface of the aluminum sheet becomes 0.3 to 1.0 µm, The thus grained aluminum sheet may be optionally washed with water or chemically etched. The etching solution is generally chosen from aqueous solutions of acids or bases capable of dissolving aluminum. However, etching agents must be those which can form a film on the etched surface, said film being composed of a component which originates from the etching solution and is different from aluminum. Preferred examples of the etching agents include basic materials such as sodium hydroxide, potassium hydroxide, trisodium phosphate, disodium hydrogenphosphate, tripotassium phosphate or dipotassium hydrogenphosphate, and acidic materials such as sulfuric acid, persulfuric acid, phosphoric acid, hydrochloric acid and salts thereof. However, salts of metals having an ionization tendency smaller than that of aluminum are not preferred, because an undesirable film is formed on the surface to be etched. For example, zinc, chromium, cobalt, nickel and copper salts are not preferred. It is most preferred that the concentrations and temperatures of these etching agents are set so that the aluminum or its alloy is etched at a solution velocity of 0.3 to 40 g/m² per minute of immersion time. However, setting may be made so as to give lower or higher solution velocity. The etching is conducted, for example, by immersing the aluminum sheet in the etching solution or coating it with the etching solution. It is preferred that the aluminum sheet is treated to such an extent that the etched rate is in the range of 0.5 to 10 g/m². As the etching agent, aqueous solutions of bases are preferred, because their etching velocity is high. However, since smut is formed, a desmut treatment is usually carried out. An acid such as nitric acid, sulfuric acid, phophoric acid, chromic acid, hydrofluoric acid or borofluoric acid is used for the desmut treatment. If desired, the etched aluminum sheet is washed with water and anodized. The anodic oxidation can be carried out by any conventional process. In one embodiment, an anodized film can be formed on the surface of the aluminum sheet by allowing direct current or alternating current to flow through the aluminum sheet in an aqueous solution or non-aqueous solution of sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid or benzenesulfonic acid or a mixture of two or more of them. The treating conditions of the anodic oxidation vary depending on the electrolytic solutions to be used and can not be generally determined. However, the anodizing conditions are usually such that the concentration of the electrolytic solution is in the range of 1 to 80% by weight, the temperature of the solution is from 5 to 70°C, the current density is from 0.5 to 60 A/dm², the voltage is from 1 to 100 V and the electrolytic time is from 30 seconds to 50 minutes. Among the anodic oxidation treatments, there are preferred a process wherein the anodic oxidation is conducted with a high current density in sulfuric acid as disclosed in U.K. Patent 1,412,768, a process wherein the anodic oxidation is conducted in low-concentration sulfuric acid as described in U.S. Patent 4,211,619 and a process wherein the anodic oxidation is conducted by using phosphoric acid as an electrolytic bath as described in U.S. Patent 3,511,661. If desired, the thus-roughed, anodized aluminum sheet may be hydrophilized. Preferred examples of the hydropholizing treatment are a method using an aqueous solution of an alkali metal silicate such as sodium silicate disclosed in U.S. Patents 2,714,066 and 3,181,461, a method using potassium fluorozirconate disclosed in JP-B-36-22063 and a method using polyvinylsulfonic acid disclosed in U.S. Patent 4,153,461. An undercoating layer composed of a water-soluble compound can be provided on the surface of the aluminum sheet which has been roughened, anodized and optionally hydrophilized. Examples of the water-soluble compound include combinations of a water-soluble metal salt with hydrophilic cellulose (e.g., a combination of zinc chloride with carboxymethyl cellulose, a combination of magnesium chloride with hydroxyethylcellulose) disclosed in U.S. Patent 3,860,426, polyacrylamide disclosed in U.S. Patent 3,511,661, polyvinylphosphonic acid disclosed in U.S. Patent 4,153,461, amino acids and salts thereof (e.g., alkali metal salts such as Na salt and K salt, ammonium salt, hydrochloride, oxalate, acetate or phosphate) disclosed in U.S. Patent 4,801,527 and amines having a hydroxyl group and salts thereof (e.g., hydrochloride, oxalat or phosphate) disclosed in U.S. Patent 4,801,527. Among them, amino acids and salts thereof, amines having hydroxyl group and salts thereof are particularly preferred. It is preferred that the undercoating layer composed of the water-soluble compound is provided in the range of from 1 mg/m² to 80 mg/m² on a solid basis. Suitable developing solutions for the photosensitive compositions of the present invention include aqueous solutions of inorganic alkaline agents such as sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium tertiary phosphate, sodium secondary phosphate, ammonium tertiary phosphate, ammonium secondary phosphate, sodium metasilicate, sodium bicarbonate and ammonia water. Such developing solutions are added in such an amount as to give a concentration of 0.1 to 10% by weight, preferably 0.5 to 5% by weight. If desired, a surfactant or an organic solvent such as an alcohol may be added to said aqueous alkaline solution. Detailed compositions of the developing solutions appear in U.S. Patents 4,259,434; 4,469,776; 4,606,995 and 4,452,880. Examples of light sources to be used for exposure include a carbon arc lamp, a mercury vapor lamp, a xenon lamp, a tungsten lamp and a metal halide lamp. The photosensitive compositions of the present invention are excellent in coatability when coated on the support and are excellent in developability when the exposed area is developed by using the aqueous alkaline developing solution after coating, drying and image exposure. The resulting relief image has a good wear resistance and a good adhesion to the support. When they are used as printing plates, many sheets of prints of good quality can be obtained. Many sheets of prints of good quality can also be obtained even when printing is made by using UV ink. The present invention is now illustrated in more detail by reference to the following examples and synthesis examples. Synthesis Example 1 170.2 g (1.0 mole) of p-aminobenzenesulfonamide and 700 mℓ of tetrahydrofuran were placed in a 1ℓ three-necked flask equipped with a stirrer, a cooling coil and a dropping funnel and stirred in an ice-water bath. 52.3 g (0.5 mole) of methacrylic acid chloride was added dropwise from the dropping funnel to the mixture over a period of about one hour. After the completion of dropping, the ice-water bath was removed and the mixture was stirred at room temperature for 30 minutes and then stirred further for one hour while heating it in an oil bath at 60°C. After the completion of the reaction, the reaction mixture was introduced into 3 ℓ of water with stirring, stirred for 30 minutes and filtered to obtain N-(p-aminosulfonylphenyl)methacrylamide as a white solid. The white solid was purified by recrystallizing it from a mixed solvent of water-acetone (yield: 39.3 g). 9.72 g (0.0408 mole) of the thus-obtained N-(p-aminosulfonylphenyl)methacrylamide, 7.93 g (0.0792 mole) of methyl methacrylate and 50 mℓ of N,N-dimethylformamide were placed in a 200 mℓ three-necked flask equipped with a stirrer and a cooling coil and stirred while heating them in a water bath at 64°C. 0.246 g of α,α′-azobisisobutyronitrile was added to the mixture and the resulting mixture was stirred in a nitrogen atmosphere for five hours while keeping the temperature at 64°C. After the completion of the reaction, the reaction mixture was introduced into 2 ℓ of water with stirring and then stirred for 30 minutes. The product was recovered by filtration and dried to obtain 16 g of a white solid. The molecular weight of the white solid was measured by gel permeation chromatography. The product (the high-molecular compound (a) of the present invention) was found to have a weight-average molecular weight of 49,000 (in terms of polystyrene). Synthesis Example 2 31.0 g (0.36 mole) of methacrylic acid, 39.1 g (0.36 mole) of ethyl chloroformate and 200 mℓ of acetonitrile were placed in a 500 mℓ three-necked flask equipped with a stirrer, a cooling coil and a dropping funnel and stirred in an ice-water bath. 36.4 g (0.36 mole) of triethylamine was added dropwise from the dropping funnel to the mixture over a period of about one hour. After the completion of dropping, the ice-water bath was removed and the mixture was stirred at room temperature for 30 minutes and placed in an oil bath. 51.7 g (0.30 mole) of p-aminobenzenesulfonamide was added to the reaction mixture and the resulting mixture was stirred for one hour while heating it in the oil bath at 70°C. After the completion of the reaction, the reaction mixture was poured into 1 ℓ of water with stirring and then stirred for 30 minutes. The resulting solid was recovered by filtration and slurried in 500 mℓ of water. The slurry was filtered and the product was dried to give N-(p-aminosulfonylphenyl)-methacrylamide as a white solid (yield: 46.9 g). 4.61 g (0.0192 mole) of N-(p-aminosulfonylphenyl)methacrylamide, 2.94 g (0.0258 mole) of ethyl methacrylate, 0.80 g (0.015 mole) of acrylonitrile and 20 g of N,N-dimethylacetamide were placed in a 200 mℓ three-necked flask equipped with a stirrer, a cooling coil and a dropping funnel and stirred while heating it in a water bath at 65°C. 0.15 g of V-65 (a product of Wako Junyaku Co; 2,2'-azobis(2,4-dimethylvaleronitrile)) was added to the mixture and the resulting mixture was stirred in a nitrogen atmosphere for two hours while keeping the temperature at 65°C. A mixture consisting of 4.61 g of N-(p-aminosulfonylphenyl)methacrylamide, 2.94 g of ethyl methacrylate, 0.80 g of acrylonitrile, N,N-dimethylacetamide and 0.15 g of V-65 was added dropwise from the dropping funnel to the above reaction mixture over a period of two hours. After the completion of dropping, the mixture was stirred at 65°C for additional two hours. After the completion of the reaction, 40 g of methanol was added thereto to cool it and introduced into 2 ℓ of water with stirring. After the mixture was stirred for 30 minutes, the product was recovered by filtration and dried to give 15 g of a white solid. The molecular weight of the white solid was measured by gel permeation chromatography. The product (the high-molecular compound (b) of the present invention) was found to have a weight-average molecular weight of 53,000 (in terms of polystyrene). Synthesis Examples 3 to 5 In the same way as in Synthesis Example 1 or 2, high-molecular compounds (c) to (e) given in Table 1 were synthesized. These high-molecular compounds were found to have a weight-average molecular weight of 9,000 to 80,000 (in terms of polystyrene). Examples 1 to 5 and Comparative Example 1 The surface of an aluminum sheet was grained by using a nylon brush and an aqueous suspension of pumice stone having a particle size of 37 µm (400 mesh) and thoroughly washed with water. The aluminum sheet was etched by immersing it in a 10% sodium hydroxide at 70°C for 60 seconds, washed with running water, neutralized and washed with 20% HNO₃ and then washed with water. The resulting aluminum sheet was subjected to an electrolytic roughening treatment with a quantity of electricity of 160 Cb/dm² in an aqueous solution of 1% nitric acid by using a sine wave alternating current under a condition of V A = 12.7 V. The surface roughness was measured and found to have a roughness (Ra) of 0.6 µm, The aluminum sheet was then subjected to a desmut treatment at 55°C for two minutes by immersing it in an aqueous solution of 30% H₂SO₄. The resulting aluminum sheet was then anodized at a current density of 2A/dm² in an aqueous solution of 20% H₂SO₄ to give a film of 2.7 g/m² in thickness. The following five photosensitive solutions [A]-1 to [A]-5 with variation in the kinds of the high-molecular compounds in the photosensitive solutions [A] were prepared. The anodized aluminum sheet was coated with each of these photosensitive solutions and then dried at 100°C for two minutes to prepare each of photosensitive lithographic plates [A]-1 to [A]-5. The coating weight was 2.5 g/m² on a dry basis. The high-molecular compounds which were used in the photosensitive solutions, [A]-1 to [A]-5, are given in Table 2. Photosensitive solution [A] Ester of naphthoquinone-1,2-diazide-5-sulfonyl chloride with pyrogallolacetone resin (described in Example 1 of U.S. Patent 3,635,709) 0.45 g High-molecular compound of the present invention (Table 2) 1.10 g 2-(p-Methoxyphenyl)-4,6-bis (trichloromethyl)-s-triazine 0.02 g Oil Blue ≠603 (a product of Orient Kagaku Kogyo KK) 0.01 g Methyl ethyl ketone 10 g Methyl cellosolve 10 g As comparative Example, the aluminum sheet was coated with the photosensitive solution (C) in the same way as in the Photosensitive solutions [A] to prepared a photosensitive lithographic plate [C]. The coating weight was 2.5 g/m² on a dry basis. Photosensitive solution [C] Ester of naphthoquinone-1,2-diazide-5-sulfonyl chloride with pyrogallolacetone resin (described in Example 1 of U.S.Patent 3,635, 709) 0.45 g Cresol-formaldehyde novolak resin 1.10 g 2-(p-Methoxyphenyl)-4,6-bis (trichloromethyl)-s-triazine 0.02 g Oil Blue #603 (a product of Orient Kagaku Kogyo KK) 0.01 g Ethylene chloride 10 g Methyl cellosolve 10 g A positive transparent original image of line drawing and halftone image was closely contacted with the surface of the photosensitive layer to each of the photosensitive lithographic plates [A]-1 to [A]-5 and [C] and exposure was conducted at a distance of 70 cm by using a 30 A carbon arc lamp. The exposed photosensitive lithographic plates [A]-1 to [A]-5 and [C] were developed by immersing them in an 8-fold diluted aqueous solution of DP-4 (Trade name, manufactured by Fuji Photo Film Co., Ltd.) at 25°C for 60 seconds. Printing was made on the best quality paper by using the resulting lithographic plates [A]-1 to [A]-5 and [C], commercially available normal ink and UV ink on a KOR type printer (manufactured by Heidelberg). The final number of sheets of paper printed by the lithographic plates [A]-1 to [A]-5 and [C] was examined. The results are shown in Table 2. Lithographic plate (Ex No.) High-molecular compound used The number of sheets of printed paper by normal ink The number of sheets of printed paper by UV ink [A] - 1 EX. 1 compound (a) of the invention 60,000 30,000 [A] - 2 EX. 2 compound (b) of the invention 65,000 35,000 [A] - 3 EX. 3 compound (c) of the invention 55,000 25,000 [A] - 4 EX. 4 compound (b) of the invention 65,000 40,000 [A] - 5 EX. 5 compound (e) of the invention 60,000 35,000 [C] Comp. Ex. 1 cresol-formaldehyde novolak resin 50,000 8,000 It is apparent from Table 2 that the lithographic plates [A]-1 to [A]-5 (Examples 1 to 5) obtained by using the high-molecular compounds are superior to the plate [C] of Comparative Example in the number of sheets of printed paper as well as the printing durability even when any of a normal ink and a UV ink is used. Examples 6 to 8 and Comparative Example 2 The surface of an aluminum sheet of 0.24 mm in thickness was grained by using a nylon brush and an aqueous suspension of pumice stone having a particle size of 37 µm (400 mesh) and thoroughly washed with water to prepare a substrate [I]. The substrate [I] was etched by immersing it in a 10% sodium hydroxide solution at 70°C, washed with running water, neutralized and washed with 20% HNO₃ and washed with water. The resulting substrate was subjected to an electrolytic roughening treatment with a quantity of electricity of 400 Cb/dm² in an aqueous solution of 0.7% nitric acid by using a sine wave alternating current under a condition of 12.7 V, and then washed with water to prepare a substrate [II]. The substrate [II] was treated to such an extent that the dissolved amount of the surface thereof in an aqueous solution of 10% sodium hydroxide reaches 0.9 g/m². The substrate was washed with water, subjected to a desmut treatment by neutralizing it with a 20% nitric acid solution and washing it and then anodized in an aqueous solution of 18% sulfuric acid to give an oxide film of 3 g/m². The resulting aluminum sheet was coated with each of booth photosensitive solutions [D]-1 to [D]-2 with variation in the kinds of the high-molecular compounds in the following photosensitive solution [D]. The coated sheet was dried at 100°C for two minutes and photosensitive lithographic plates [D]-1 to [D]-2 were prepared. Further, the following photosensitive solutions [E] and [F] were prepared and the aluminum sheet was coated with each of them in the same way as in [D]-1 to [D]-2 to prepare photosensitive lithographic plates [E] and [F]. The coating weight was 2.5 g/m² on a dry basis. The high-molecular compounds which were used for the photosensitive solutions, [D]-1 to [D]-2 and [E], are given in Table 3. Photosensitive solution [D] Photosensitive solution [E] Photosensitive solution [F] A photosensitive solution wherein 1.1 g of a cresol (m-isomer 60%, o-isomer 40%)-formaldehyde resin (weight-average molecular weight: 4,000) was used in place of the high-molecular compound in the photosensitive solution (D). The evaluation of photosensitive lithographic plates [D]-1 to [D]-2, [E] and [F] was made in the same way as in Examples 1 to 5 and Comparative Example 1. The results are shown in Table 3. It is apparent from Table 3 that the lithographic plates [D]-1 to [D]-2 and [E] (Examples 6 to 8) obtained by using the high-molecular compounds are superior to the plate [F] of Comparative Example in their printing durability, even when any of a normal ink and a UV ink is used. Lithographic plate (Example No.) High-molecular compound used The number of sheets of printed paper by normal ink The number of sheets of printed paper by UV ink [D] - 1 EX. 6 compound (b) of the invention 65,000 33,000 [D] - 2 EX. 7 compound (d) of the invention 65,000 38,000 [E] EX. 8 compound (b) of the invention 65,000 33,000 [F] Comp. Ex. 2 cresol-formaldehyde resin 50,000 8,000 Examples 9 to 24 Photosensitive lithographic plates were prepared in the same manner as in Example 6, except for using the high-molecular compounds shown in Table 4, and using a photosensitive solution containing 0.007 g of organic acids having different pKa values. A positive transparent original image of line drawing and halftone image was closely contacted with the surface of the photosensitive layer to each of the photosensitive lithographic plates and exposure was conducted at a distance of lm by using a 2kW metal halide lamp. The exposed photosensitive lithographic plates were developed by immersing them in an 8-fold diluted aqueous solution of DP-4 (Trade name, manufactured by Fuji Photo Film Co., Ltd.) at 25°C for 60 seconds. A deletion-speed of the lithographic plates thus obtained was measured as is shown below. A deletion liquid disclosed in Example 7 of U.S. Patent 4,396,703 was coated on the images and the coating time sufficient to have no stain on the images when the lithographic plate was subjected to printing was measured. The coating time means the time after coating of the deletion liquid on the images until completion of washing-out the deletion liquid by water. As is apparent from the results of Table 4, the deletion-speed becomes higher when an organic acid having a pKa value of 3 or less was used.

Claims: A photosensitive composition comprising a high-molecular compound having at least one sulfonamide group in its side chains insoluble in water, but soluble in an aqueous alkaline solution and a positive working o-naphthoquinone diazide compound, wherein said high-molecular compound is obtained by polymerizing a low-molecular compound selected from the group consisting of compounds represented by formula (I) to (V) wherein X¹ and X² each represent -0- or -NR⁷; R¹ and R⁴ each represent H or CH₃; R² and R⁵ each represent an alkylene group having from 1 to 12 carbon atoms, a cycloalkylene group having from 3 to 12 carbon atoms, an arylene group having from 6 to 12 carbon atoms or an aralkylene group having from 7 to 14 carbon atoms, each of which may have one or more substituent groups; R³ represents a hydrogen atom, an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R⁶ represents an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R⁷ represents a hydrogen atom, an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R⁸, R¹⁰ and R¹⁴ each represent a hydrogen atom, a halogen atom or a methyl group; R⁹ represents an alkylene group having from 1 to 12 carbon atoms, a cycloalkylene group having from 3 to 12 carbon atoms, an arylene group having from 6 to 12 carbon atoms or an aralkylene group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R¹¹ and R¹⁵ each represent a single bond, an alkylene group having from 1 to 12 carbon atoms, a cycloalkylene group having from 3 to 12 carbon atoms, an arylene group having from 6 to 12 carbon atoms or an aralkylene group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R¹² and R¹⁶ each represent an alkylene group having from 1 to 12 carbon atoms, a cycloalkylene group having from 3 to 12 carbon atoms, an arylene group having from 6 to 12 carbon atoms or an aralkylene group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R¹³ represents a hydrogen atom, an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; R¹⁷ represents an alkyl group having from 1 to 12 carbon atoms, a cycloalkyl group having from 3 to 12 carbon atoms, an aryl group having from 6 to 12 carbon atoms or an aralkyl group having from 7 to 14 carbon atoms, each of which may have one or more substituents; the above mentioned substituents being selected from an alkoxy group having from 1 to 6 carbon atoms, an alkanoyl group having from 1 to 6 carbon atoms, an alkanoyloxy group having from 1 to 6 carbon atoms, an alkoxycarbonyl group having from 1 to 6 carbon atoms, an N-alkylcarbamoyl group having from 1 to 6 carbon atoms, a halogen atom or a cyano group or, in the case of an arylene, aralkylene, aryl or aralkyl group, the above mentioned substituents being additionally selected from an alkyl group having from 1 to 6 carbon atoms; and Y¹ and Y² represent a single bond or The photosensitive composition of claim 1, wherein said high-molecular compound has a weight-average molecular weight of from 5,000 to 300,000. The photosensitive composition of claim 1, wherein the amount of said high-molecular compound to be incorporated into the photosensitive composition is from 5 to 95% by weight. The photosensitive composition of claim 1, wherein the amount of the positive working photosensitive compound in the photosensitive composition is from 10 to 50% by weight. The photosensitive composition of claim 1, wherein said composition further comprises an alkali-soluble high-molecular-weight compound selected from the group consisting of a phenol-formaldehyde resin, a cresol-formaldehyde resin, a phenol-modified xylene resin, a poly(hydroxystyrene), and a poly(halogenated hydroxy styrene). The photosensitive composition of claim 5, wherein said alkali-soluble high-molecular-weight compound has a weight-average molecular weight of from 500 to 20,000 and a number-average molecular weight of from 200 to 60,000. The photosensitive composition of claim 5, wherein the amount of said alkali-soluble high-molecular-weight compound in the photosensitive composition is not more than 70% by weight. The photosensitive composition of claim 1, wherein said composition further comprises an organic acid having a pKa of at most 3.0. The photosensitive composition of claim 8, wherein said organic acid is selected from an organic sulfonic acid or an organic sulfinic acid. The photosensitive composition of claim 9, wherein said organic acid is selected from the group consisting of naphthalene-2-sulfonic acid, naphthalene-l-sulfonic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, mesitylenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, m-benzene-di-sulfonic acid, cyclohexylsulfamic acid, p-toluidine-2-sulfonic acid, pyridine-3-sulfonic acid, phenyl J-acid (7-anilino-4-hydroxy-2-naphthalenesulfonic acid), p-toluene sulfinic acid, benzylsulfinic acid, and methanesulfinic acid. The photosensitive composition of claim 9, wherein the amount of the organic acid is in the range of from 0.05 to 5% by weight based on the total weight of the composition. The photosensitive composition of claim 1, wherein in formula (I) and (II) X¹ and X² each represent -NH-; R¹ and R⁴ each represent H or CH₃; R² and R⁵ each represent an alkylene group having from 2 to 6 carbon atoms, a cycloalkylene group having 5 or 6 carbon atoms, or an optionally substituted phenylene or naphthylene group; R³ represents H, an alkyl group having from 1 to 6 carbon atoms, a cycloalkyl group having 5 or 6 carbon atoms, or an optionally substituted phenyl or naphthyl group; and R⁶ represents an alkyl group having from 1 to 6 carbon atoms, a cycloalkyl group having 5 or 6 carbon atoms, or an optionally substituted phenyl or naphthyl group. The photosensitive composition of claim 1, wherein said high-molecular compound is obtained by copolymerizing the low-molecular compound with at least one compound selected from the group consisting of a methacrylate, an acrylate, a methacrylamide, an acrylamide, acrylonitrile, methacrylonitrile, methacrylic acid and acrylic acid. The photosensitive composition of claim 13, wherein 10 to 90 mole% of said low-molecular weight compound based on the copolymer, is copolymerized.

Inventors: AOSHIMA KAITARO, NAGASHIMA AKIRA, AOSHIMA, KAITARO, NAGASHIMA, AKIRA, AOSHIMA, KAITARO FUJI PHOTO FILM CO., LTD., NAGASHIMA, AKIRA FUJI PHOTO FILM CO., LTD.
Applicants: FUJI PHOTO FILM CO LTD, FUJI PHOTO FILM CO., LTD.
Application year: 1989
Main classification: G03F7
IPC codes: G03F7