DE2405915A1 - LIGHT-SENSITIVE LITHOGRAPHIC PRINTING PLATE - Google Patents

Description

7th February 1974

_P781o 240S915

FUJI PHOTO S ¹ IIJl CO., LTD.

No. 210, Fakanuma, Minami Ashigara-shi Kanagawa, Japan

Photosensitive lithographic printing plate

The invention relates to a photosensitive photopolymerization type lithographic printing plate, in particular one in which a layer which is impermeable to oxygen on a photopolymerizable (polymerizable by light) layer Protective layer is provided which consists of a water-insoluble and dilute aqueous alkali or dilute aqueous alkali, which is preferably 10 vol .- / l or contains less of a water-soluble organic solvent, soluble linear organic polymer with a ' high molecular weight.

As a photopolymerization type photosensitive material is subject to polymerization inhibition by oxygen, was previously used as an oxygen-impermeable protective layer on a light-sensitive layer one made of a water-soluble organic high molecular weight polymer, such as polyvinyl alcohol or polyvinyl pyrrolidone are used to prevent this polymerization inhibition.

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Such a water-soluble organic high molecular The polymer effectively prevents the inhibition of polymerization by oxygen, however, it has the disadvantage that the surface when left standing under high humidity conditions becomes sticky.

The aim of the invention is therefore to provide an improved photosensitive indicate a lithographic printing plate in which this disadvantage does not occur.

It has now been found that this target with a photosensitive Photopolymerization type lithographic printing plate can be achieved in which on a photopolymerizable Layer a linear organic polymer with high molecular weight that is insoluble in water, but in a dilute aqueous alkali solution or in a dilute aqueous alkali solution, which is preferably 10 vol .- ^ or less a water-soluble organic solvent, is soluble, as a protective layer impermeable to oxygen is provided. That is, it will be one with ammonia neutralized aqueous solution or an emulsified aqueous solution of a linear organic polymer with a high molecular weight, which in a dilute aqueous alkali solution or a dilute aqueous alkali solution, which preferably contains 10% by weight or less of a water-soluble organic solvent, is soluble, in Porm an oxygen-impermeable protective layer on the photosensitive surface of a photosensitive lithographic Pressure plate applied.

The invention relates to a photosensitive lithographic Photopolymerization type printing plate, which thereby is characterized by the fact that it consists of

(a) a carrier with a hydrophilic surface,

(b) a photopolymerizable layer applied thereon,

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Containing an ethylenically unsaturated compound with 2 or more polymerizable vinyl groups of the acrylic or methacrylic type, a photopolymerization initiator in a small amount and, if desired, a linear organic polymer compatible with the above-mentioned ethylenically unsaturated compound with a high molecular weight, the photopolymerizable layer at 20 ⁰ C is a gel or a solid and can be developed with a dilute aqueous alkali solution or a dilute aqueous alkali solution which preferably contains 10% by volume or less of a water-soluble organic solvent, and

(c) a water-insoluble, oxygen-impermeable film with a dry film thickness of 0.2 to 5 Microns on the photosensitive surface of the printing plate, consisting of the dried coating film an aqueous solution neutralized with ammonia or an emulsified aqueous solution one in a dilute aqueous alkali solution or a dilute aqueous, water-soluble organic solvent is preferred linear organic polymer soluble in an amount of alkali solution containing 10% by volume or less with a high molecular weight.

For the preparation of the above-described water-insoluble Film can be a linear organic polymer with a high molecular weight, which has carboxyl groups on the side chains has, is solid at room temperature, has a molecular weight of about 1CGO or higher, in a dilute aqueous alkali solution or in a dilute aqueous alkali solution, which is preferably 10% by volume or less of a water-soluble organic solvent, is soluble and has an acid value of 30 or more.

Specific examples are acidic cellulose derivatives such as oil

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Loseacetathydrogenphthalat, Hydroxypropylmethylcelluloseehydrogenphthalat and Hydroisypr opylnethylc e 1 IuIοs ehydrogenhexahydrophthalat, acidic polyvinyl alcohol! derivatives, as they are made by the reaction of cyclic acid anhydrides, such as phthalic anhydride, setrahydrophthalic anhydride, setrahydrophthalic anhydride, or with a succinic anhydride anhydride, or with a succinic anhydride and succinic anhydride with a succinic anhydride and sometimes with a succinic anhydride and succinic anhydride with a succinic anhydride or with a succinic anhydride and succinic anhydride with a succinic anhydride and sometimes with a succinic anhydride and succinic anhydride. % can be obtained, such as polyvinyl acetate / polyvinyl alcohol / polyvinyl hydrogen phthalate and polyvinyl alcohol / polyvinyl hydrogen phthalate, acrylic acid copolymers, methacrylic acid copolymers, itaconic acid copolymers, crotonic acid copolymers, crotonic acid copolymers, crotonic acid copolymers to esterified / stric acid copolymers (e.g. ! Copolymers. Examples of suitable liisclipolynerisate that can be used are 2-Hydro: ^ 7-ethyl methacrylate / methacrylic acid (ratio 9 ^ / 5 G-sw .- ^) -, St ^ / rol / ltaconic acid (ratio 90 / 1C wt .-: ^) -, vinyl acetate / -crotonic acid (ratio 93/7 wt .- ^ 'O mixed polyols. Casein and shellac as well as high molecular weight natural substances can also be used.

A film which is insoluble in water but which is insoluble in a dilute aqueous alkali solution or in a dilute aqueous alkali solution which is preferably 10 vol

Alkali solution which is preferably 10 Vol.-f-a or less Contains water-soluble organic solvent, is soluble, can be prepared by applying an acidic linear organic polymer with a high molecular weight and carboxyl groups on the Ssitenketten in the form of a Aqueous solution neutralized with ammonia or an alkaline solution aqueous solution on a photopolymerizable layer Tind subsequent drying. Because this film is insoluble in water its surface does not become sticky, in contrast to the well-known water-soluble pilms, even if it is is left in place under high humidity conditions.

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In addition, the film can be developed with a developer consisting of a dilute aqueous alkali solution or a dilute aqueous alkali solution, preferably 10%. -% or less of a water-soluble organic solvent, can be completely removed from the photopolymerizable layer. The water-insoluble protective film used here should preferably be immiscible with the photopolymerizable layer to which it is applied. If a protective film that is miscible with the photopolymerizable layer is used, (Peil of the photopolymerizable layer migrates into the protective film when the protective film is dried.

When the water-insoluble protective film on the surface the photopolymerizable layer in the form of an aqueous solution neutralized with ammonia or an emulsified aqueous solution Solution is applied, the coating can also be formed with the addition of a surfactant. A suitable one Concentration of the coating solution can be within the Range of about 5 *> is about 60% by weight and a suitable one Surfactant is an anionic surfactant which is present in an amount from about 0.01 to about 1% by weight is used. A suitable amount of coating for the photopolymerizable layer and the water-insoluble, the oxygen impermeable layer may be within the range of from about 0.2 to about 10, preferably from 1 to 3 g / m or from about 0.1 to about 5, preferably from 1 up to 2 g / m.

For a photosensitive lithographic printing plate with a hydrophilic surface, aluminum is best suited. The surface of the aluminum can either be untreated or treated or coated to maintain a hydrophilic surface. In addition, the surface be mechanically, chemically or electrochemically roughened in order to ensure the adhesion of a layer applied to it as well as the

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To improve retention of their hydrophilic properties. Examples of further suitable carriers with a hydrophilic Surface are 'tin plated steels, with phosphate treated steels, stainless steels, coated with aluminum Steels, polyethylene terephthalate films laminated with aluminum, Zinc with a roughened surface, papers coated with a hydrophilic inorganic colloid and Plastic films as well as with a hydrophilic organic polymer Papers coated with a high weight of ilolelnilar and plastic films.

The photopolymerizable layer of the invention contains an ethylenically unsaturated compound nit 2 or more polymerisierb _a ren vinyl groups from the acrylic or methacrylic type in "a molecule, a small Henge a photopolymerization initiator in a narrow !! of etr; a 0.05 to about 10, preferably from 0.5 to 2% by weight and, if necessary, a linear organic polymer compatible with the ethylenically unsaturated compound described above and having a high molecular weight. At 20 ° C., the photopolymerizable layer is in the form of a gel or a solid it can be developed with a dilute aqueous alkali solution or a dilute aqueous alkali solution preferably containing 10% by volume or less of a water-soluble organic solvent.

Examples of the ethylenically unsaturated ones described above Compounds are divalent or trivalent acrylates or Listhacrylate, such as Ji ^ hylenglykoldiacrylat, Diethyleneglykoldiacrylat, Triethylene glycol diacrylate, ethylene glycol dimethacrylate, Trimethylolpropane triacrylate, pentaerythritol triacrylate and trinethylolpropane trimethacrylate, Bisacrylamides, de NjH-Methylenbisacrylamid, Xylylenbisacrylamid and phenylenebisacrylamide, as well as vinyl urethane compounds, the 2 or more polymerizable vinyl groups in contain a molecule, which by adding a hydroxyl

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group-containing vinyl monomers of the general formula Ch ₂ = C (E ₁ ) OOOGH ₂ OH (R ₂ ) OH, where B ₁ and E _{2 are} H and CH ₅ , to a polyisocyanate compound with 2 or more isocyanate groups in one molecule «,

Examples of linear organic polymers with a high molecular weight, those with an ethylenically unsaturated Compound compatible with carboxylic acid groups with an acid number of 30 or more, e.g. up to about 4-00, on the side chains, which in a dilute aqueous alkali solution or in a dilute aqueous alkali solution, the preferably 10% by volume or less of a water-soluble one organic solvents are acrylic acid copolymers, Methacrylsauremi3cb.polymeri3a.te, itaconic acid copolymers, partially esterified maleic anhydride / styrene copolymers, acidic cellulose derivatives such as cellulose acetate phthalate, Hydro ^ iypropylmethylcellulose phthalate and Hydrosypropyl methyl cellulose hexahydrophthalate, and acidic Polyvinyl aiko ho lderi vat e, such as porvvi ^ rl alcohol polyvinyl hydrogen phthalate and polyvinyl acetate / polyvinyl alcohol / polyvinyl hydrogen phthalate.

Examples of photopolymerization initiators that can be used are benzoin, benzoin alkyl ethers, such as benzoin ethyl ether and benzoin isopropyl ether, bicarbony compounds such as biacetyl and dibenzyl, aromatic sulfonyl chlorides such as 1-ITaphthalenesulfonyl chloride and 2-l-taphthalenesulfonyl chloride, such as benzoin isopylbenzone compounds, such as michleret'sopylbenzone compounds, such as antiacethronyl chloride, and 2-chloroanthraquinone and 2-t-butylanthraquinone, and ITaphthothiazole compounds such as 3-methyl-2-bensoylmethylene naphtho (1,2-a) -thiazole and 3-ethyl-2-benzoylmethyleinaphtho (1,2-a) thiazole. In addition, acridine and 4,5-diphenyl-2- (o-chlorophenyl) imidazole can be used. Further examples are S-phenylacridine, Michler's ketone / ^z i-, 5-diphenyl-2- (o-chlorophenyl) imidazole, Michler's ketone / 2-chloroanthraquinone and Michler's ketone /

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Benzoin ethyl ether.

As the developer, for the above-described photopolymerizable layer, a "dilute aqueous alkali or dilute aqueous alkali solution having a concentration within the range of about 0.05 to about 5 wt .-%, preferably 10 Yoi -.% Or less of a water-soluble organic Examples of alkaline compounds that can be used to prepare the same are inorganic compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium silicate, sodium bicarbonate, ammonium hydroxide, di- and trisodium phosphate and di- and triammonium phosphate, and organic compounds Examples of suitable water-soluble organic solvents are n-propyl alcohol, isopropyl alcohol, benzyl alcohol, ethyl cellosolve, butyl cellosolve, ethylene glycol 1-monoethyl ether, ethylene glycol monobutyl ether and diacetone alcohol active agent (e.g., an anionic surfactant such as isopropylnaphthalene sodium sulfate, lauryl sodium sulfate and the like, in an amount of about 0.1 to about 5% by weight), a dye (e.g., a basic dye such as crystal violet, methylene blue, in an amount from 0.5 to 5% by weight), a salt for preventing swelling and a salt for etching the base metal, such as FeCl, KF and the like, can be added in an amount of 0.001 to 0.1% by weight .

In addition, the above-described photopolymerizable A dye, a pigment, a filler, a thermopolymerization inhibitor and a plasticizer are added to the layer will.

The following examples are intended to explain the invention in more detail without, however, restricting it thereto. The ones specified therein Parts, percentages, ratios and the like relate to

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unless otherwise stated, by weight. example 1

(A) To 174 g (1.0 mol) of 2,4-tolylene diisocyanate were 14-3 g (1.1 mol) of 2 ~ hydroxyethyl methacrylate was added and the materials were reacted for 2 hours at 6O ⁰ C to each other. Then 4-0.2 g (0.3 mol) of trimethylolpropane and 90 g of ethyl acetate were added as a solvent and the materials were reacted with one another for 7 hours while passing air through the mixture at 80 ° G, with an 80% strength Solution of a vinyl urethane compound (I) in ethyl acetate was obtained.

(B) 1000 g (1.0 mol) of polyethylene glycol became 4-00 g (2.12 Mol) xylylene diisocyanate was added and the materials were reacted with one another at 14-0 ° 0 for 30 minutes. Then were 260 g (2.0 mol) of 2-hydroxyethyl methacrylate were added and the. Materials were reacted with each other for 5 hours while bubbling air through the mixture at 80.degree. C., with a Vinyl urethane compound (II) was obtained.

On an aluminum plate grained with a nylon brush and which had been surface-treated with a 1% sodium polyacrylate solution and then with a 1% phosphoric acid solution, using a coating rod, Hr. 8 a coating compound of the composition given below is applied in the form of a layer and then dried ^{at 100 ° C. for 2 minutes:}

80% solution of the vinyl urethane compound

(I) (molecular weight about 1000) in

Ethyl acetate. 75 g

' ^: Vinyl urethane compound (II)
(Molecular weight about 17ΟΟ) 40 g

Michler's ketone. '2g

2-chloroxanthone '2g

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240 591 5 0.1 S. 0.2 S. 400 S. S.

2,6-di-t-butyl cresol Oil Blue

Isopropyl alcohol methyl ethyl ketone

0.1 % of the surfactant Monogen Y-100 (trade name for sodium lauryl sulfate by Pirma Daiichi Eogyo Takuhin Co.) was added to a 10% ammonia-neutralized aqueous solution (pH = 7.0) of a vinyl acetate / crotonic acid copolymer with a Crotonic acid content of about 7 w / v% was added, and the solution was applied to the dried coated aluminum plate using a No. 8 coating rod and then dried at normal temperature. A negative film containing letter images was brought into contact with this photosensitive plate and exposed for 60 seconds to a carbon arc lamp of 3 kW at a distance of 70 cm. After the exposure, the photosensitive plate was developed with the following developer to obtain a lithographic printing plate with a sharp relief image:

Water 950 g

Butyl cellosolve 50 g

Monogen Y-100; 10 g.

Diethanolamine 5 g

A vinyl acetate / crotonic acid copolymer in the form of a Protective layer applied, which prevents the inhibition of polymerization by oxygen.

The photopolymerizable layer used here was subject to, in comparison to other photopolymerizable layers, for example those that contain an acrylic acid mixture or contained a trimethylolpropane triacrylate, hardly (only with difficulty) a polymerization inhibition by oxygen,

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However, if no, impermeable to oxygen protective film was present ₉ irapde the sensitivity by the strength of vacuum in a Yakuumexpozd-erirngsvorrichtting up to a certain degree "affected. In a reduced pressure of 60 mm Hg in a Yakuumexponierungsvorrichtung the seventh step was, for example, completely cured as a poIge of 60 seconds exposure using a continuous step wedge, while at 0 mm Hg with an exposure of 60 seconds the second step was fully cured Layer the vinyl acetate / crotonic acid mixed polymer was intended as a protective layer.

Example 2

(A) 370 g (2.12 mol) of 2,4-tolylene diisocyanate were added to 850 g (1.0 mol) and the mixture was Polytetramethylenoxyglykol react for 30 minutes at 14-0 ⁰ C allowed, then 260 g of (2 , 0 mol) of 2-hydroxyethyl methacrylate added 'and the mixture was reacted for 7 hours at 80 C while air was passed through, whereby a vinyl urethane compound (III) was obtained. 100 g.Hydroxypropylmethylcellulosehydrogenphthalat with a phthalate content of 32%, 20 g of glycidyl methacrylate, 3.2 g of triethylamine as a catalyst and 200 g of acetone was added and the mixture was allowed to react for 1 week- at 50 ⁰ C. After the reaction, the reaction mixture was diluted with methanol and poured into a large amount of water to precipitate a polymer. The precipitated polymer was dried at room temperature under reduced pressure, and glycidyl methacrylate-modified hydroxypropylmethyl cellulose hydrogen phthalate was obtained in a yield (reaction ratio) of 68%.

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Granulated using a nylon brush Aluminum plate subjected to anodic oxidation in dilute sulfuric acid and a surface treatment with sodium silicate was subjected to ITr. 8 a coating compound the following composition in the form of a Layer applied and then dried for 2 minutes at 100 ° C;

Hydroxypropyl methacrylate modified with glycidyl methacrylate (viscosity at 20 ° G in an acetone / methanol (7/3, based on weight) mixture = 150 cPj. 20 g methyl methacrylate / methacrylic acid (35/15? Based on weight) copolymer { [ ^] in methyl ethyl ketone at 30 ⁰ G = 0.15) '. 10 g

Trimethylolpropane triacrylate 30 g

80% solution of the vinyl urethane compound (I)

of Example 1 in ethyl acetate "25 g

Vinyl urethane compound (III) of Example 2 (molecular weight about 1500)

Michler's ketone Benzoin ethyl ether p-Hethoxyphenol Oil Blue

Isopropyl alcohol methyl ethyl ketone

After drying, a 10% ammonia-neutralized aqueous solution of a vinyl acetate / crotonic acid copolymer which contained 1 % of the surface-active agent of Example 1 was prepared using a coating rod Hr. 8 applied and then dried at normal temperature. A negative photographic film containing letter images was brought into contact with this photosensitive plate and then exposed for 30 seconds with a carbon arc lamp of 3 kW at a distance of? 0 cm. After the exposure, the developer

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20th S. O 2 e S. 2 e S. 0.1 ε 0.3 4-00 4-95

of Example 1 and a lithographic printing plate having a sharp relief image was obtained. These lithographic printing plate showed excellent printing resistance on.

Example 3

The procedure of Example 2 was repeated, but this time instead of the 10% "neutralizing" with ammonia th aqueous solution of the vinyl acetate / crotonic acid polymeric polymer a 10% emulsified aqueous solution of the 'vinyl' acetate / crotonic acid copolymer Cebian A 50123 (trade name from Daicel Co.) was used to obtain a good protective film. This photosensitive plate was exposed and developed in the same manner as in Example 2 to obtain a lithographic printing plate became.

Example 4-

A 10% aqueous solution of neutralized with ammonia milk casein (pH = 7 »2) was dissolved in Form.einer layer as a protective film instead of the 10% _v of Example 2 is applied with ammonia-neutralized aqueous solution of the vinyl acetate / crotonic acid copolymer.

Example 5

On the aluminum plate used in Example 2, a photosensitive solution of 4 g of a methyl methacrylate A was applied Methacrylic acid (9/1, based on the weight) copolymer (intrinsic viscosity at 30 ° C in methyl ethyl ketone as solvent = 0.115), 6 g of di - '(2'-acryloxyethyl) -2,4-tolj-lendiurethane, 0.1 g 3-methyl-2-benzoylmethylene naphtho (1,2-a) thiazole, 0.1 g triphenylarsine, 0.01 g p-methoxyphenol and 90 g of a methyl cellosolve acetate / gyclo-.

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Hexanone (1/1 by weight) solvent mixture was applied and dried at 100 ° C for 2 minutes. A 10 / aige ^ Am with m oniak neutralized aqueous solution (pH = 7 »2) of Hydror ^^ ropylmethylacetylcellulosehydrogenphthalat on the thus obtained photosensitive plate (degree of substitution: 0.27 hydroxypropyl group, methoxy group 1.88, acetyl 0.55) phthalyl 0.19) using an ITr coating rod. 12 applied and then dried ^{at 100 0 G for one minute.} This photosensitive plate was exposed and developed as in Example 2 to obtain a lithographic printing plate having a sharp relief image. The oxygen-impermeable protective film from the gallows aqueous solution neutralized with ammonia was not dissolved in 7 / water, but it did dissolve in a developer, ie a weak aqueous alkali solution.

Although the invention has been preferred with reference to FIG Embodiments explained in more detail, but it is clear to the person skilled in the art that they are in no way limited thereto and that these can be changed and modified in many ways without thereby falling outside the scope of the present Invention is abandoned.

Patent claims:

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Claims (1)

Claims .J A photosensitive lithographic printing plate of the photopolymerization type characterized in that it is composed of (a) a carrier with a hydrophilic surface, (b) a photopolymerizable layer applied thereon, containing an ethylenically unsaturated compound having 2 or more polymerizable vinyl groups of the acrylic or methacrylic type and a photopolymerization initiator, the photopolymerizable layer at 20 ° C is a gel or a pesticide and with a dilute aqueous alkali solution or a dilute aqueous alkali solution containing a water-soluble organic solvent is developable, and (c) a water-insoluble, oxygen-impermeable PiIm with a dry layer thickness of. 0.2 to 5 Microns on the photosensitive surface of the printing plate, consisting of the dried coating film of an aqueous solution neutralized with ammonia or an emulsified aqueous solution, a dilute aqueous alkali solution or a dilute one aqueous alkali solution containing a water-soluble organic solvent soluble linear organic Polymer with a high molecular weight. - 2. Printing plate according to claim 1, characterized in that the water-insoluble, oxygen-impermeable PiIm a PiIm from an acidic cellulose derivative, an acidic polyvinyl alcohol derivative, an acidic polyvinyl acetate, an acrylic acid copolymer, a methacrylic acid copolymer, a 409832/0900 Itaconic acid copolymer, a crotonic acid copolymer • a partially esterified maleic anhydride / - Styrene copolymer, casein or shellac is. 3. Printing plate according to claim 1 and / or 2, characterized in that that the water-insoluble, oxygen-impermeable PiIm is a linear organic polymer with a high molecular weight and an acid number of at least 30. 4-, printing plate according to at least one of claims 1 to 3j characterized in that the thickness of the water-insoluble, oxygen-impermeable film within the Range from 0.1 to 5 g / m. lies" 5 printing plate according to at least one of claims 1 to 4-, characterized in that the support is made of aluminum, a tin-plated steel, and a phosphate-treated one Steel, a stainless steel, an aluminum-coated steel, an aluminum-laminated polyethylene terephthalate film, surface-grained zinc, a paper coated with a hydrophilic inorganic eolloid or Plastic film or one coated with a hydrophilic organic polymer having a high molecular weight Made of paper or plastic film. 6. Printing plate according to at least one of claims 1 to 5, characterized in that it is a divalent or trivalent acrylate or as the ethylenically unsaturated compound Contains methacrylate, a bisacrylamide or a vinyl urethane. 409832/0900