JPS6211851A - Photosensitive composition - Google Patents

Abstract

PURPOSE:To form an image high in printing resistance by incorporating an ethylenically unsaturated additionally polymerizable compound, a specified film-forming polymer, a photopolymerization initiator, a negatively acting diazo resin, and a higher fatty acid amide being liquid at ordinary temperature. CONSTITUTION:The photosensitive composition is prepared by incorporating (1) the ethylenically unsaturated additionally polymerizable compound, (2) a specified film-forming polymer soluble or swellable in an aqueous solution of alkali, (3) the photopolymerization initiator, (4) the negative acting diazo resin, and (5) the higher, fatty acid amide being liquid at ordinary temperature. As the compound (1), a monomer or oligomer having a boiling point of >=100 deg.C, and at least one additionally polymerizable unsaturated group in the molecule, and a molecular weight of <=10,000 can be used. As said polymer (2), acidic vinyl polymers having -COOH, -PO3H2, -SO3H, or the like groups in the molecule and an acid value of 50-200 are enumerated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a photosensitive composition suitable for a photosensitive lithographic printing plate. More specifically, the present invention relates to a novel photopolymerizable composition that reduces the influence of oxygen during plate making.

[Conventional technology]

Attempts have been made to use photopolymerizable compositions as image forming layers suitable for photosensitive lithographic printing plates. For example, a basic composition consisting of an organic solvent soluble combination, an ethylenically unsaturated addition polymerizable compound and a photopolymerization initiator, as described in Japanese Patent Publication Sho≠Bu-3 Core No. 1, Japanese Patent Publication Sho AY-3
Compositions with improved curing efficiency by introducing unsaturated double bonds into organic solvent soluble polymers as described in the aoai publication, Tokko Sho Tie-3TrtoJ No., Tokko Sho J3-
Compositions using novel photopolymerization initiators, such as those described in Japanese Patent No. 2740j and British Patent No. 1,311°l22, are known, and some of them are in practical use. However, when any of the photosensitive compositions is used as a photosensitive layer of a lithographic printing plate, polymerization is significantly inhibited by oxygen during image exposure. It could not be used practically. In order to reduce the effect of oxygen on polymerization inhibition, there has been an attempt to add a negative-acting diazo resin to the above-mentioned photoblind composition. Such an attempt was made, for example, in
F-cootrJj No., JP-A No. 13134, JP-A No. 7R4T4A2, JP-A No. 17-19423
No. 0, and US Pat. Nos. ≠, Jet, and Tag No. 2.

However, the effects of both methods are insufficient.

[Purpose of the invention]

It is therefore an object of the present invention to provide a novel photosensitive composition which improves the above-mentioned drawbacks and which provides high printing durability in lithographic printing plates.

[Structure of the invention]

The present inventor reduced the influence of oxygen without providing an oxygen barrier layer by using a composition in which higher fatty acid amide, which is solid at room temperature, is added to a photopolymerizable composition containing a negative-acting diazo resin. The present invention was completed by discovering that a high printing durability can be obtained in a lithographic printing plate.

The present invention provides (1) an ethylenically unsaturated addition polymerizable compound, (
2) A photosensitive composition containing a polymer that is soluble or swellable in alkaline water and capable of forming a film, (3) a photopolymerization initiator, (4) a negative-acting diazo resin, and (5) a higher fatty acid amide that is solid at room temperature. It is a thing.

A photopolymerizable composition entirely containing a negative-acting diazo resin is less susceptible to polymerization inhibition by oxygen in the air than a photopolymerizable composition containing no diazo resin. This is thought to be because diazo resin generates nitrogen gas that is inert to polymerization during exposure, but as mentioned above, it is difficult to completely eliminate the effect of oxygen just by adding diazo resin. . I
However, when a higher fatty acid amide that is solid at room temperature is added to a photopolymerizable composition containing this diazo resin, the higher fatty acid amide stands out on the surface of the photosensitive layer during coating and drying.
Forms a kind of oxygen barrier layer. A method of forming an oxygen barrier layer by adding a so-called wax agent such as a higher fatty acid to a photopolymerizable composition that does not contain a diazo resin is known, but the oxygen blocking effect is sufficient. do not have. Oxygen barrier layers obtained by adding higher fatty acids tend to deteriorate over time when exposed to conditions such as high temperatures, and their ability cannot be said to be sufficient. However, if a higher fatty acid amide is added to a photosensitive layer made of a photopolymerizable composition containing a diazo resin, it is virtually unaffected by oxygen in the air during exposure, and images with high printing durability can be formed. becomes possible.

In addition, the oxygen barrier layer shows little deterioration over time and has excellent long-term storage stability.

The ethylenically unsaturated addition-polymerizable compound used in the present invention is a molecule @io having at least one addition-polymerizable unsaturated group in one molecule and having a boiling point of 1oo0c or more at normal pressure.
It is a monomer or oligomer of ooo or less. Such monomers or oligomers include monofunctional acrylates and methacrylates such as polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, and phenoxyethyl(meth)acrylate: polyprolene glycol di(meth)acrylate; Polypropylene di(meth)acrylate, trimethylolethane tri(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, metaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate , hexanediol di(meth)acrylate, tri(acryloyloxyethyl)isocyanurate, polyhydric alcohols such as glycerin and trimethylolethane added with ethylene oxide or propylene oxide and then converted into (meth)acrylates, Special Public Showa 4Ar-'I/70
No. 1, Special Publication No. 10-40311, Japanese Patent Publication No. Shoj/-37/
Urethane acrylates as described in 3 Aromatic Publications, JP-A No. 4 TR-A No. 113, JP-A No. 7-4
Polyfunctional acrylates and methacrylates such as polyester acrylates, epoxy acrylates made by reacting epoxy resin and (meth)acrylic acid, which are described in t3/ri No. 1 and Tokuko Shoyo-30112O publications. I can give it to you. Furthermore, Japan Adhesive Association Journal Vol. λ0
．． 11;, 7. For 300-3or, those introduced as photocurable monomers and oligomers in -di can also be used.

The alkaline water-soluble or swellable film-forming polymer used in the present invention includes -C00H in the polymer.
1-POaHz, -8O3H, -8O2NH2 maku have 18O2NHCO- groups and can include acidic vinyl copolymers with an acid value of 10 to 000.

Examples of such copolymers include benzyl (meth)acrylate/(meth)acrylic acid/other addition-polymerizable copolymers as required, as described in Japanese Patent Publication No. Vinyl monomer copolymer; Tokkosho!
methacrylic acid/methyl methacrylate or ethyl/alkyl methacrylate copolymer as described in Goo, No. 341327; and other Japanese Patent Publications No. 31-/2677, Japanese Patent Publication No. 12J/7 of 1983, Japanese Patent Publication No. j4t-ta λ7
(meth)acrylic acid copolymer as described in each publication No. 23; Allyl (meth)acrylate/(meth)acrylic acid/ Other addition-polymerizable vinyl monomer copolymers as required: JP-A-Kokai Shoj Turf 10 Hiro, which is obtained by adding pentaerythritol triacrylate to the maleic anhydride copolymer described in the publication by half-esterification. etc. can be mentioned.

In particular, benzyl (meth)acrylate/(meth)acrylic acid/other addition-polymerizable vinyl monomer copolymers and allyl (meth)acrylate/as required
A meth(acrylic acid)/other addition-polymerizable vinyl heptamer copolymer is suitable.

The composition ratio of these ethylenically unsaturated addition polymerizable compounds and the film-formable polymer is O8j: ri, j-j
The range of :t is preferable, and the more preferable range is /:ri~3
It's near.

As the photopolymerization initiator used in the present invention, US Pat.
．． 3 Otsu 7. Bubu No. 7, the α-carbonyl compounds described in U.S. Patent No. 2.347.470, and U.S. Pat. ++ Aromatic acyloin compounds in which r, r, and 2 are substituted with asylloin ethers as described in the specification of US Pat. Polynuclear quinone compounds described in Patent No. J, 0≠t, /27, U.S. Patent No. 1, Fil, No. 7j1, U.S. Patent No. j, jl? , 347
The combination of triarylimidazole dimer/p-aminophenyl ketone described in US Patent No. 3,7
61. ．． Acridine and phenazine compounds described in US Patent No. 2J, 2/2. P7
Examples include oxadiazole compounds described in the specification of No. 0. Its usage amount is approximately 0,j based on the total composition.
A suitable weight ratio is r~/j, more preferably 2-10% by weight.

Examples of higher fatty acid amides that are solid at room temperature used in the present invention include lauric acid amide, tridecylic acid amide, myristic acid amide, pentadecylic acid amide, palmitic acid amide, heptadecylic acid amide, stearic acid amide, nonadecanic acid amide, Arachinic acid amide, behenic acid amide, lignoceric acid amide, cerotinic acid amide, heptacosonic acid amide, montanic acid amide, melisic acid amide, lafcelic acid amide, etc. e6 can be obtained.

Preferably, higher fatty acid amides having carbon number/7 or more are preferred, especially those having a melting point of 1000C or more. The amount of these higher fatty acid amides added to the entire composition is 0. j-IOi layer %, preferably /-7% by weight is suitable.

In addition to these higher fatty acid amides, higher fatty acids such as behenic acid and stearic acid can also be used in combination.

The negative-acting diazo resin L7 used in the present invention is suitably one that is substantially water-insoluble and soluble in an organic solvent aJ. Such diazo resins include ≠-diazodiphenylamine, /-diazo-μ-N.

N-dimethylaminobenzene, l-diazo-≠-N, N
-diethylaminobenzene, /-diazo-≠-N-ethyl-N-hydroxyethylaminobenzene, /-diazo-≠-N-methyl-N-hydroxyethylaminobenzene, l-diazo-λ.

j-jethoxy-≠-benzoylaminobenzene, /-
siaxi≠-N--<ndylaminobenzene, l-diazo-4'-N, N-dimethylaminobenzene, /-diazo-l-morpholinobenzene, l-diazo-1,! −
Dimethoxy (1-p-tolylmercaptobenzene, l
-Diazo-λ-ethoxy/O- -4-N,N-dimethylaminebenzene, p-diazo-
Dimethylaniline, /-diazo-λ, 1-dibutoxy-gumorpholinobenzene, /-diazo-λ, j-
Jetoxy-7-morpholinobenzene, l-diazo-
λ, j-dimethoxy≠-morpholinobenzene, l-
Diazo-J, t-jetoxy-glymorpholinobenzene, l-diazo-λ, j-jetoxy-11-p-tolylmercaptobenzene, l-diazo-3-ethoxy-hiro--N-methyl-N/<ndyl aminobenzene, /
-Dilcy 3-chloro-4A-N,N-diethylaminobenzene,/-diazo-3-methyl-≠-pyrrolidinobenzene, l-diazo-λ-chloro≠-N,N-dimethylamino-j-methoxy Benzene, l-diazo-3-methoxy-V-pyrrolidinobenzene, 3-methoxy-Hiro-
Diazo monomers such as diazodiphenylamine, 3-ethoxy-gudiazodiphenylamine, 3-(n-propoxy)-Koichidiazodiphenylamine, 3-(isopropoxy)-≠-diazodiphenylamine, formaldehyde, acetaldehyde, propionaldehyde , butyraldehyde, isobutyraldehyde, or benzaldehyde, respectively in molar ratios /:/-
/", 0.j, preferably /:0.I to /:0.t by a usual method [7] The reaction product of the condensate obtained by condensation with an anion can be mentioned. As an anion, , tetrafluoroboric acid, hexafluorophosphoric acid, triisopropylnaphthalenesulfonic acid, !-nitroorthotoluenesulfonic acid, !-
Sulfosalicylic acid, J, t-dimethylbenzenesulfonic acid, 2. ≠, j−) dimethylbenzenesulfonic acid, λ
-Nitrobenzenesulfonic acid, 3-chlorobenzenesulfone m, 3--10mobenzenesulfonic acid, 2-fluorocafrylnaphthalenesulfonic acid, dodecylbenzenesulfonic acid, /-naphthol-j-sulfonic acid, twomethoxy≠-hydroxy! Examples include -benzoyl-benzenesulfonic acid and -radluenesulfonic acid. Among these, alkyl aromatic sulfonic acids such as hexafluorophosphoric acid, triinpropylnaphthalenesulfonic acid and λ,j-dimethylbenzenesulfonic acid are particularly suitable.

The amount of these diazo resins added to the total composition is 1 to 3
0 weight ratio, more preferably 3 to 1j weight ratio.

In addition to the above, it is preferable to further add a thermal polymerization inhibitor to the photosensitive layer, such as hydroquinone, p-methoxyphenol, di-1-butyl-p-cresol, pyrogallol, 1-butylcatechol, benzoquinone, μ, 4t
'-thiobis(J-methyl-A-t-butylphenol), co,2'-methylenebis(4t-methyl-7-j
-7' tylphenol), tumerkabutobenzimidazole, etc. are useful, and in some cases, dyes or pigments, and pH indicators as printing agents may be added for the purpose of coloring the photosensitive layer.

Furthermore, as stabilizers for diazo resin, cynic acid, sinorous acid,
l 3 − can be obtained by adding tartaric acid, citric acid, malic acid, dipicolinic acid, polynuclear aromatic sulfonic acid and its salts, sulfosalicylic acid, etc. as necessary.

The photosensitive composition as described above is dissolved in a suitable solvent such as, for example, two-methoxyethanol, 2-methoxyethyl acetate, propylene gellicol monomethyl ether, 3-methoxypropanol, 3-methoxypropyl acetate, methyl ethyl ketone, ethylene dichloride, etc. Each of these is dissolved in an appropriate mixed solvent and coated on a support. It is preferable to use an ultrasonic dispersion machine during dissolution, as this will speed up the dissolution. The amount of coverage is approximately 0.0% by weight after drying. A range of /f/m2 to about IOt/m2 is suitable, and more preferably o,j-tr/m2.

Supports suitable for applying the photosensitive composition of the present invention include:
It is a dimensionally stable plate-like object. Such dimensionally stable plate-like materials include those conventionally used as supports for printing plates, and they can be suitably used in the present invention. Such supports include paper, paper laminated with plastics (e.g. polyethylene, polypropylene, polystyrene, etc.), plates of metals such as aluminum (including aluminum alloys), zinc, copper, etc. Cellulose acetate, cellulose triacetate, cellulose propionate, cellulose butyrate, vinegar@cellulose butyrate, cellulose nitrate,
Examples include films of plastics such as polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc., and paper or plastic films laminated or vapor-deposited with metals, such as those made of metal. Among these supports, aluminum plates are particularly preferred because they are extremely dimensionally stable and inexpensive. Furthermore, a composite sheet in which an aluminum sheet is bonded to a polyethylene terephthalate film as described in Japanese Patent Publication No. Sho≠I/1327 is also preferred.

In addition, in the case of a support having a metal surface, especially aluminum, surface treatments such as graining treatment, immersion treatment in an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate, etc., or anodization treatment are performed. Preferably. Also, U.S. Patent No. λ, 7111. As described in the Ott specification, an aluminum plate grained and then immersed in a sodium silicate aqueous solution, Special Publication Show≠7
-! As described in Japanese Patent Publication No. 2003/2009, an aluminum plate is anodized and then immersed in an aqueous solution of an alkali metal silicate. The above anodizing treatment can be carried out using, for example, an inorganic acid such as phosphoric acid, chromic acid, sulfuric acid, or boric acid, or an organic acid such as oxalic acid or sulfamino acid, or an aqueous or non-aqueous solution of these salts alone or in combination. The method is also carried out by applying an electric current to an aluminum plate in an itwI solution as an anode.

Also effective is silicate electrodeposition as described in US Pat. No. I,4J1,462.

Furthermore, JP-A No. 44J-27≠TRI, JP-A-FJ
It is also useful to use a surface treatment that combines a support coated with electrolytic grains with the above-mentioned anodic oxidation treatment and sodium silicate treatment as disclosed in JP-A-11402 and JP-A-11402-0103.

Further, it is also preferable to use brush grain, electrolytic grain, anodic oxidation treatment, and sodium silicate treatment as disclosed in Japanese Patent Application Laid-Open No. 2003-29003. Furthermore, after these treatments, it is also suitable to apply an undercoat with a water-soluble resin such as polyvinylphosphonic acid, a polymer or copolymer having a sulfonic acid group in the side chain, polyacrylic acid, or the like.

These hydrophilic treatments are performed not only to make the surface of the support hydrophilic, but also to prevent harmful reactions with the photosensitive composition provided thereon, and to improve the adhesion with the photosensitive layer. This is done for the purpose of improving the quality of life.

On the layer of the photosensitive composition provided on the support, a material with excellent oxygen barrier properties such as polyvinyl alcohol, acidic cellulose, etc. is used to completely prevent the polymerization inhibition effect caused by oxygen in the air. A protective layer made of a polymer may also be provided. The method of applying such a protective layer is described in detail in, for example, US Pat.

A photosensitive plate having the photosensitive composition of the present invention provided on a support is imagewise exposed using a light source rich in ultraviolet rays such as a metal halide lamp or a high pressure mercury lamp, and then treated with a developer to leave the photosensitive layer unexposed. A lithographic printing plate is prepared by removing the portion and finally applying a gum liquid. Preferred examples of the developer are benzyl alcohol and two-phenoxyethanol.

An alkaline aqueous solution containing a small amount of an organic solvent such as two-butoxyethanol, e.g.
No. 71 and No. 3.41, and those described in No. 4A10 can be mentioned. Furthermore, JP-A-Shoto-,
zttoi issue, special public show j4-j ≠ reference, same it-+
The developers described in the publications of λrto are also excellent as developers for photosensitive printing plates using the photosensitive composition of the present invention.

〔Example〕

Hereinafter, it will be explained in more detail based on examples.

Note that "excellent" indicates weight %.

-/l'- Example/ A substrate was prepared by the method disclosed in Japanese Unexamined Patent Publication No. 21-23, J-6-6. That is, the thickness is 0,30. .

The surface of the aluminum plate was grained using a nylon brush and a water suspension of Nomise Stone made by San〇〇Mesh, and then thoroughly washed with water. 70 to io4 sodium hydroxide
After being etched by immersion at °C for up to seconds, it was washed with running water, neutralized with 20% NOx, and washed with water. This was subjected to electrolytic surface roughening treatment using an alternating sinusoidal waveform current under the condition of 2.7 V and an anode special electricity amount of /40 coulombs/4 m2 in a /% nitric acid aqueous solution. When the surface roughness was measured, it was θ, tμ (expressed as Ra). 1.20 qb H2SO4
Current density in aqueous solution, 2A/dff! No. 2 was anodized for 2 minutes to a thickness of 2°7 f/m2.

Thereafter, it was immersed in a 700C sodium silicate lambda, rq6 aqueous solution for 7 minutes, washed with water, and dried.

The following photosensitive solution m was prepared.

Photosensitive liquid (1) 0 trimethylol protontri, 2oy acrylate Q poly(allyl methacrylate/methacrylic acid) copolymerization molar ratio 10/20 copoly02, ≠-trichloromethyl-co1(v'-
methoxynaphthyl) ≦-triadi1 0p-diazodiphenylamine, 2f condensate with formaldehyde, hexafluorophosphate O-behenic acid amide /VO propylene glycol ester /00f thyl ether op -/77 (Dainippon Ink @ Made /,
If Fluorinated Surfactant) After filtering this photosensitive solution (1), use a spin coater on the substrate and apply 1 to 2.0% of the dried baking soda. /m2. Drying was carried out for λ minutes at tθ0C, and this was designated as sample A.

As a comparative example, a photosensitive liquid containing no behenic acid amide was prepared from the photosensitive liquid i11, and was coated and dried in the same manner as Sample B.

In order to compare the degree of influence of oxygen on these plates, a PS step guide (△D = 0./, gray scale in which the transmission density changes discontinuously at t) manufactured by Fuji Photo Film ■ was placed on top of the sample. A printer manufactured by Nuark in the United States (
Exposure was performed using a light source (2KW metal halide lamp). At this time, change the vacuum of the printing frame of the printer and use Fuji Photo Film's PS plate negative developer DN-3C.
was diluted with water to remove unlighted areas.

The number of step guides on the plate after development is shown in Table 1. Sample A was not affected by vacuum and had high sensitivity.

1+2/- Table 7 Effect of degree of vacuum regardless of sensitivity (gray scale stamp guide solid plate number) When this sample A=z was printed on a z printing machine Heidelberg KOR-D, more than 100,000 prints were obtained. . In sample B, printing defects occurred on the J-way.

In addition, samples A were left under conditions of 3 days under the conditions of ``C, 7j section 1'' (, H), and then printed after printing in the same manner as above. A printed matter was obtained.

EXAMPLE A play if sample C was obtained by applying and drying the following photosensitive liquid (2) in place of the photosensitive liquid of Example 1 in the same manner.

-,2,2- Photosensitive liquid (2) Copolymerization of 0 dipentaerythritol hexa 209 acrylate 0 poly(allyl methacrylate/10t benzyl methacrylate/methacrylic acid) molar ratio 70//j//j Coalescence 0 Photopolymerization initiator with the following structure 2vop-Hexafluorophosphate of condensate of diazodiphenylamine and 3t formaldehyde 0 Behenic acid amide /, jlO Propylene glycol monomethythyl θOt L ether 0 Methyl alcohol 300fO Methyl ethyl ketone joofop-/77 ( (manufactured by Dainippon Ink ■, / If fluorine-based surfactant) As a comparative example, a photosensitive solution was prepared by removing the ihenic acid amide from the photosensitive solution (2), and coated and dried in the same manner. The plate was designated as sample D.

These samples C1D were treated in the same manner as in Example 1, and the influence of evacuation was investigated. As shown in Table 2, Sample C was less affected by vacuum and had higher sensitivity than Sample D.

Table 2. Effect of vacuum degree regardless of sensitivity (PS step/guide solid step number) Sample C exposed after vacuuming and without vacuuming, and Sample D exposed after vacuuming, printed after development processing. Machine Heidelberg KOR-D
Sample C produced over 100,000 prints in all cases, but sample D... There was a printing defect due to the cursor.

Example 3 Instead of the photosensitive liquid of Example (1), the following photosensitive liquid (3) was applied and dried in the same manner to prepare a plate.

Photosensitive liquid (3) O tri(acryloyloxyethyl) 30f isocyanurate O poly(benzyl methacrylate/jOf methacrylic acid) copolymerization molar ratio 7! /11 copolymer O Behenic acid amide /-0fO behe7
Acid /, of-λ! -O propylene glycol mono/! 00f/methyl ether A transparent negative film 't-ff1 was exposed and developed on the obtained plate to obtain a printing plate. Example (1) of this version
10, which was printed using the same printing machine KOR-D.
It was possible to print 10,000 copies.

〔Effect of the invention〕

The photosensitive composition of the present invention is not easily affected by oxygen during exposure, and therefore can form images with high printing durability. Therefore, a printing plate obtained from a photosensitive printing plate using this has excellent printing durability.

Patent applicant: Fuji Photo Film Co., Ltd. -Co4-

Claims (1)

[Claims] (1) ethylenically unsaturated addition polymerizable compound, (2) alkaline water soluble or swellable polymer capable of forming a film, (3) photopolymerization initiator, (4) negative working diazo resin, and (5) ) A photosensitive composition containing a higher fatty acid amide that is solid at room temperature.