JPS5948768A - Lithographic printing plate requiring no dampening water - Google Patents

Abstract

PURPOSE:To increase the printing resistance of a lithographic printing plate requiring no dampening water and having a silicone rubber layer as an ink repelling layer, by incorporating a specified org. titanate into an adhesive layer to improve the adhesive strength between the silicone rubber layer and the photosensitive layer. CONSTITUTION:A photosensitive layer contg. an orthoquinonediazido compound such as a partially esterified product of naphthoquinone-1,2-diazido-5-sulfonic acid of novolak resin is formed on a support of A, Cu or the like. The photosensitive layer is coated with an adhesive layer contg. an org. titanate represented by the formula (where each of R1 and R3is 1-20 C alkyl, aryl, cycloalkyl or alkenyl; R2 is H, 1-20 C alkyl, aryl, cycloalkyl or alkenyl; L is a chelating ligand; and n is 0-3). A silicone rubber layer is then formed on the adhesive layer as an ink repelling layer to obtain the desired lithographic printing plate requiring no dampening water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lithographic printing plate that does not require dampening water and has a silicone rubber layer as an ink repellent layer, and particularly the lithographic printing plate that has improved adhesion between the silicone rubber layer and the photosensitive layer. It is related to.

In order to perform lithographic printing using silicone rubber as an ink repellent layer without using dampening water, printing plates having various 11η compositions have been proposed.

Among these are those lined with a support; '7 on the water source layer;
As a negative working lithographic printing plate coated with a silicone rubber layer and requiring no dampening water 2 For example, JP-A-56-80
No. 046 proposes a presensitized lithographic printing plate comprising a photoreleasable 11 photolayer backed by a support and a silicone rubber layer on the second layer.

Furthermore, JP-A-55-110249 proposes a lithographic printing plate in which a silicone rubber layer containing aminorane is provided on a pre-solubilized photosensitive layer backed by a support.

In such printing plates, for example, the silicone rubber layer in unexposed areas may peel off during development, or the silicone rubber layer may be exposed to light due to surface 1 scratch resistance or printing durability during operations such as development and printing. Strong adhesion between the layers and the silicone rubber layer is of paramount importance.

Japanese Patent Publication No. 49-5790, 49-73202.49-7
7702.41-86103. '49-126407
Both issues discuss the formation of plate grooves to improve the adhesion between the silicone rubber layer and the photosensitive material layer.

There is no particular distinction between negative working and positive working. It's perfect for negative working! There is 1+f Kaisho 55-59466.

However, it is not possible to mix a silane coupling agent or a silicone primer into the silicone layer as described in these documents, or to make the silicone layer a mixture of a one-component room-temperature curing silicone rubber and a 2ak addition type noricone rubber. .

The silicone layer lacks homogeneity and the cohesive force of the silicone rubber is reduced, resulting in a silicone layer with poor scratch resistance, and if the plate surface is scratched during development printing, it will easily cause scumming. The technique of mixing a silane coupling agent or an amine compound into a photosensitive material layer generally tends to cause side reactions with the highly reactive photosensitive material, and also poses problems in terms of storage stability.

In order to eliminate these drawbacks and strengthen the adhesion between the photosensitive layer and the silicone rubber layer, a silicone rubber layer exists between the photosensitive layer and its -4- silicone rubber layer to bond both layers together. It has been proposed to provide an adhesive layer on the substrate (Japanese Unexamined Patent Publication No. 59466/1983). The adhesive layer proposed here uses amino 7 run.

However, aminosilane is generally used when coating.

The disadvantage is that the stability of the coating liquid is poor. Furthermore, when considering the balance of adhesion between the silicone rubber layer and the photosensitive layer (for example, while the adhesion between the silicone rubber layer and the photosensitive layer is strong, the silicone rubber layer must be easily removed during development). The coating conditions are narrow, and it is difficult to select the optimal coating surface according to various conditions.

The present inventors have conducted intensive studies to solve these problems, and as a result, have arrived at the present invention described below.

That is, the present invention provides a lithographic printing plate that does not require dampening water and comprises a support, a photosensitive layer containing an orthoquinone diazide compound, an adhesive layer, and a silicone rubber layer in this order, characterized in that the adhesive layer contains an organic titanate. 1: This relates to a waterless lithographic printing plate.

The organic titanate used in the adhesive layer of the present invention is a compound represented by the following formula:

T1(onl)4. Tj, (oR2), (ocoR
3) 4-, Tj(.R2) n ``4'-n Also, the ligand referred to here is β-diketone, glycol, hydroxycarboxylic acid, or ketoester.

Keto alcohol or nitrogen ligand.

Typical examples of the above general formula include:

For example, tetra-iso-propoxy titanium, tetrayu n-
Tetraalkyl titanates such as butoxytitanium and tetrastearoxytitanium.

Di-iso-propoxy bis(acetylacetonato) titanium, di-n-butquinruacetonato) titanium, di-n-butquine bis(triethanolamina].) titanium dihydroxy/.bis(
titanium chelates such as lactato) titanium, te] lactato) titanium, trin
Also included are titanium chelates and polymers such as -butoquinotitanium monostearate and titanium tetrabenzoate.

In addition, isoprobilt (dioctyl phosphate-1,
) titanate, isopropyl tris(nooctyl pyrophosphate) titanate, bis(dioctyl pyrophosphate) oxyacetate titanate, bis(dioctyl pyrophosphate) ethylene titanate, bis(dioctyl phosphate) ethylene titanate, and other phosphorus-containing titanates are also used. It can be done.

These organic titanates contain not only one type but also two or more types.
It is also possible to use them together.

The photosensitive layer containing an orthoquinone diazide compound used in the present invention refers to Japanese Patent Application Laid-Open No. 55-110249 and Japanese Patent Application No.
A photo-solubilizable photosensitive layer and a photo-peelable photosensitive layer as proposed in No. 156871 are common.

Therefore, the photo-solubilizable photosensitive layer includes a photosensitive layer in which the ethanol-soluble component containing the orthoquinonediazide compound is preferably 20% by weight or less, more preferably 15% by weight or less. Orthoquinone diazide compound has 1,
2-quinonediazide or 1,2-naphthoquinonediazide (1/) structure 9 Usually sulfonic acid derivative 2 For example, reaction of orthoquinonediazide sulfonic acid and its derivatives with a compound having a hydroxyl group or an amine group (especially a polymer compound) It is used in the form of esters or amides obtained from

A preferred photosensitive layer for carrying out the present invention is a partial ester of naphthoquinone-1,2-diazido-5-sulfonic acid of a novolac resin with esterification 1f of 65 to 65%.

The novolak resin here refers to phenol or m-
It is a novolac-type phenol obtained by condensing cresol with formaldehyde.

Furthermore, the photoreleasable photosensitive layer is one in which the exposed portion of the photosensitive layer is not substantially removed by development, but the seven lycone rubber layers thereon are removed.

Nondiazides constituting such a photosensitive layer include 9, for example, benzoquinone-1,2-dianthosulfonic acid ester with polyhydroxyphenyl, naphthoquinone-1,2
Examples include esters of -diazide sulfonic acid and pyrogallol acetone resin, and esters of naphthoquinone-1,2-diazide sulfonic acid and phenol formaltech novolak resin.

The known quinonediazide yn is modified by crosslinking with a polyfunctional compound or bonded with a monofunctional compound to make it sparingly soluble or insoluble in the t''Jtf phase frk, thereby producing a photoreleasable photosensitive layer.

For example, as a crosslinking agent used to introduce crosslinking (11η structure), polyfunctional isonoanates are used.

Example Vf, Halaphenylene diisocyaner 1-, 2
．． 4-Dimensions are 2.6-Tolninincyanate, 4.
4-diphenylmethane diisocyanate, hexamethylene diisocyanate, inphorone diisocyanate-1.
or adducts thereof, or polyfunctional Epoquine compounds 1 such as polyethylene glycol diglycidyl ethers, polypropylene glycol diglycidyl ethers, bisphenol A diglycidyl ether,
1) mer-y-ri-propane triglycidyl ether and the like.

These thermal curing processes must be carried out within a temperature range of 150° C. or lower so that the photosensitivity of the photosensitive material is not lost.

For this purpose, a catalyst or the like is used in combination.

That's sweet, f17. Examples of the method for introducing a poorly soluble or insoluble component onto the image plane include esterifying, amidating, or urethanizing the active group of the photosensitive compound. The compound to be reacted with the active group of the photosensitive compound may be a low-molecular compound or a relatively high-molecular compound, or a monomer may be graft-polymerized to the photosensitive compound.

The photoremovable photosensitive layer used in the present invention includes:

Particularly preferred is a structure in which a partially esterified product of 7-tokyno-1,2-/7-dido-5-sulfonic acid tophenol polyaltechnovolac resin is cross-linked with polyfunctional or monofunctional iso/anate. Obtained by denaturation.

The thickness of the photosensitive layer of the present invention is approximately 01 to 100 μm, preferably approximately 05 to 10 μm; however, if it is too thin, defects such as pinholes are likely to occur during coating.

If it is too thick, it is disadvantageous from an economic point of view.

In fact, other components may be added to the photosensitive layer for purposes such as improving coating film formation or adhesion to the support within a range that does not impair the effects of the present invention. It is possible to add dyes to make it visible.

The silicone rubber layer used in the present invention is mainly composed of polysiloxane having a molecular weight of several thousand to several hundreds of thousands and having repeating units such as primary repeating units.

+S i-0± ■ (where n is an integer of 1 or more, R is an alkyl group, alkenyl group, or phenyl group having 1 to 10 carbon atoms, and 60% or more of R is preferably a methyl group. 1 to 1.) Such linear organic polysiloxanes can be crosslinked into a silicone rubber by adding an organic peroxide and subjecting them to heat treatment or the like.

A crosslinking agent is also added to the linear organopolysiloxane. As a crosslinking agent, acetoxy 7 is used in so-called room temperature (low l crystal) curing silicone rubber.
Ran, ketoxime silane, alkoxy silane, aminosilane, amidosilane, etc. 2 Usually, they are combined with linear organic polysiloxanes with hydroxyl groups at the end, and are of the acetic acid type, deoxime type, and dealcohol type, respectively. , deamined type, deamidated type silicone rubber. Generally, a small amount of an organic tin compound or the like is further added to the silicone rubber as a catalyst.

The thickness of the silicone rubber layer is approximately 0.5-100 mm.

Preferably, it is about 05 to 1071, and if it is too thin, problems may arise in terms of printing durability.

On the other hand, if the thickness is too thick, it is not only economically disadvantageous, but also makes it difficult to remove the silicone rubber layer during development, resulting in a decrease in image reproducibility.

In the lithographic printing plate of the present invention, adhesion between the support and the photosensitive layer is very important for basic plate performance such as image quality, reproducibility, and printing durability. adhesion-improving components can be added to each layer.

The support must be flexible enough to be set in a normal lithographic printing machine and capable of withstanding the load applied during printing. As a typical example.

Examples include metal plates such as aluminum, copper, and steel, plastic films such as polyethylene terephthalate, paper, and rubber. The support may be composite. These sheets' second ha.

Prevention of rations 1) - It is also possible to further coat the substrate for other purposes.

Furthermore, for the purpose of protecting the silicone rubber layer forming the surface of the lithographic printing plate that does not require dampening water, a thin protective film may be laminated on the surface of the silicone rubber layer.

As explained above, the lithographic printing plate which does not require dampening water and which is used in the present invention is manufactured as follows.

i A photosensitive layer is coated on the base support using a conventional coater such as a reverse roll coater, an air knife coater, or a Meyer bar coater, or a rotary coater such as a Whaler. After drying and heat curing if necessary, an adhesive layer is applied on the photosensitive layer in the same manner, and after drying, a silicone rubber solution is applied on the adhesive layer in the same manner.
A heat treatment is performed for several minutes at a temperature of 0.degree. C. to fully cure and form a silicone rubber layer.

If necessary, cover the silicone rubber layer with a protective film using a laminator or the like.

The lithographic printing plate manufactured in this way that does not require dampening water is 9
For example, it is exposed to actinic light through a vacuum-adhesive film. The light source used in this exposure process is one that generates a lot of ultraviolet rays, such as a mercury lamp, a carbon arc lamp, or a xenon lamp.

Metal halide lamps, fluorescent lamps, etc. will be used.

Next, when the printing plate is levered with a developing vat containing a TJl developer, the silicone comb layer or photosensitive layer in the exposed area is removed, exposing the photosensitive layer surface or the substrate surface, and the ink receiving layer 4 is removed.
Becomes a department.

The printing plate of the present invention not only has strong adhesion between the photosensitive layer and the silicone comb layer, but also has the following properties:
The areas to be removed are those from which the silicone rubber layer can be selectively and easily peeled off.

Therefore, it is a well-balanced printed edition.

It is still possible to employ a wide range of conditions when applying the adhesive layer.

Furthermore, the stability of the adhesive layer coating solution as a stock solution is very good, and when an alcohol such as n-butanol is added as a coating solvent, it does not become cloudy and retains its performance even when left in the air for a long time.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 On a 0.3 mm thick aluminum plate, 0.3 mm thick,
A phenol novolak resin (manufactured by Sumitomo Bakelite: Sumirenn PR50) with a degree of esterification of 44% was applied on a composite substrate with a chloroprene rubber layer with a rubber hardness of 60 (Shore A).
A 10iffi% dioxane solution of naphthoquinone-1,2-diazide-5-sulfonic acid ester (235) was applied and dried in hot air at 60°C.

A photosensitive layer with a thickness of 3/1 was provided.

This 2 Il'CQ-n-phytoki/-hys(acetylacetonato) titanium 04 heavy area (Esso Chemical (l
'l) Manufactured by: aliphatic hydrocarbon solvent) "Iso-E"
The solution was applied and dried at 120° C. to form an adhesive layer with a thickness of 01 μm.

Furthermore, a 10% by weight n-hexane solution of a silicone rubber composition having the following composition was applied thereon.

A silicone rubber layer having a thickness of 25/l was provided by heating and curing in hot air at 120° C. for 4 minutes.

(a) 100 parts of dimethylpolyroxane (
Molecular weight 30,000 terminal hydroxyl group) (b) Methyltriacetoquinonerane 6 parts (
C) Dibutyltin acetate 02 parts The printing original plate obtained as described above was passed through a vacuum-adhesive negative film and passed through an ultra-high pressure water 1R lamp (Jet Light 2K).
W) and was exposed for 90 seconds from a distance of 1 m. The exposed plate was viewed with a developer consisting of 65 parts of ethanol/65 parts of Isopar F, and when rubbed lightly with a development band, the exposed area was easily removed and the rubber layer was exposed;
A strong silicone rubber layer remains in the unexposed areas,
A printing plate that faithfully reproduces the negative film was obtained.

Attach this printing plate to an ordinary flatbed letterpress printing machine,
When direct printing was performed on coated paper using a waterless lithographic ink [Albo GJ (manufactured by Toka Shiki Kagaku Kogyo Co., Ltd.)], a printed matter with good ink coverage overall and a sharp image was obtained.

Example 2 Esterification degree of 44 on chemical conversion treated aluminum plate (manufactured by Sumitomo Light Metals)
% of naphthoquinone-1,2- of phenol novolac resin (Sumitomo Teurez: Sumirenon PR50235);
A triple dioxane solution of azido-5-sulfonic acid ester (ethanol-soluble component: 97% by weight) was spin-coated using a Whaler and dried to form a 1.21+ photosensitive layer.

(7)-'2 VC/-n-Fil/Xyce/Vice (Ace5-/Rare Upper Tonner-) 02 weight ratio of titanium (manufactured by Esso Chemical (Pl): aliphatic hydrocarbon solvent) 'Isopar F, '/n-butanol-80F20 weight ratio solution was spin-coated with a Whaler and dried to a thickness of 0.05μ.
An adhesive layer was formed.

A 7thiaisopar E solution of a silicone rubber composition having the following composition was spin-coated onto this using a Whaler. After drying, 1
Heat cured at 20°C for 4 minutes to obtain a 22μ silicone rubber layer.

(a) 100 parts of dimethylpolysiloxane (
Molecular weight approximately 80,000 terminal hydroxyl group) (b) Vinyl tri(methyl ethyl 1.6
part oxime) silane (C) dibutyltin diacetate - 0.2 parts Aitorphine 2000) was used for 60 seconds of illumination from a distance of 1 m. The exposed version is
8 parts ethanol.

Using a developer consisting of 82 parts of Isopar and passing through an automatic developing machine at a transport speed of 30 αn/min, the exposed areas were easily removed and the surface of the chemically treated aluminum was exposed, while the unexposed areas were The silicone rubber layer remained strong, and an image that faithfully reproduced the negative film was obtained.

This printing plate was attached to an offset printing machine (Komori Sprint 2 color) and
When printing was carried out using the same without using dampening water, a printed matter with an extremely good image in which 5 to 95% of the 150-line halftone dots were reproduced was obtained. Even after printing 10,000 copies, no scumming or damage to the plate surface was observed, and printing could continue.

Example (A) A 0.24 mm thick aluminum plate (Sumitomo Light Metals) was coated with resol resin (Sumilight Resin PC!-1.Sumitomo Decorez) to a thickness of 1.7μ, and cured at 180°C for a minute. and used as a support. The following photosensitive layer composition was spin-coated onto this support and cured by heating at 120° C. for 2 minutes to provide a photosensitive layer having a thickness of 23 μm.

(a) Ester fl [48% phenol - 100 parts]
Naphthoquinone-1,2-diazide-5-sulfonic acid ester (b) of Lunovolac J6J resin (Sumilight Resinya R50235, manufactured by Sumitomo Decores) 4,4'-diphenylmethane diiso 3
0 parts cyanate (C) dibutyltin dilaure-1.02 parts (d) dioxane 2. OO'0
Part (B) Then, on top of this, tetra-iso-prophoki/
After applying a titanium 5 weight Isopar E solution using a Meyer bar coater, it was heated at 120° C. for 1 minute to form an adhesive layer with a thickness of 02 μm.

(C) Subsequently, a silicone rubber composition having the following composition was applied to this layer using a Meyer bar coater.

Heat cured at 120℃, DP 30℃ for 4 minutes to a thickness of 23μ
A silicone rubber layer was provided.

(a) 100 parts of dimethylpolyroxane (
Molecule mouse approximately 25, ooo terminal hydroxyl) (1)) Ethyl triacetoxysilane 6 wholesale (C) Dibutyltin acetate 02 parts On the printing original plate obtained as above, a 150-line halftone image was created. The negative film is vacuum-adhered according to a conventional method,
Image exposure was performed using a metalno-ride lamp. Next, this plate is immersed in an ethyl cellosolve/Isopar E (Esso Kagaku m) (5,,/95) developer and rubbed lightly with a development pad, which removes the silicone rubber layer in the exposed areas and exposes the surface of the photosensitive layer. However, images faithful to the original film were obtained.

The unexposed silicone rubber layer of this plate is not attacked by the developer, and the surface of the silicone rubber layer is not scratched during development. Moreover, the printing plate obtained in this way does not have any scratches on the plate surface due to paper dust etc. even during printing, and excellent printed matter can be obtained.

Patent Applicant Toshi Co., Ltd. - ``Hakusei Ichiyama If I!F Special Edition Agency Appearance Yasugi River'', Tono 11i! (If!'+ 7 <'l + Ii'l meditation submitted on September 13 + 1 A. 1) (1) 2. Name of defense ('11 Moisture 4z not ") ν) ゛&Printing 1'J2 generation, 141? lI Mi III +i I. Chang Island 1. N I
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Claims (2)

[Claims] (1) A dampening water-free lithographic printing plate comprising a support, a photosensitive layer containing an orthoquinone diazide compound, an adhesive layer and a silicone rubber layer in this order. A lithographic printing plate that does not require dampening water, wherein the adhesive layer contains Iso titanate. (2) The dampening water-free lithographic printing plate according to claim (1), wherein the organic titanate is at least one compound represented by the following formula. Ti(OR1)4. Ti(OR2), (OCORf
) 4-,, Ti(OR2). L4-.