JPS60133452A - Photosensitive lithographic printing plate requiring no dampening water - Google Patents

Abstract

PURPOSE:To improve the printing resistance and solvent resistance during printing by successively laminating a photosensitive layer contg. an o-quinonediazido compound and a photosetting compound or composition and a silicone rubber layer on a support by coating. CONSTITUTION:A photosetting compound or composition is incorporated into a photosensitive layer contg. an o-quinonediazido compound, and the photosensitive layer is covered with a silicone rubber layer. The photosetting compound or composition has considerably lower sensitivity than the o-quinonediazido compound. A photosetting compound or composition different from the o-quinonediazido compound in the photosensitive wavelength region may be incorporated. The resulting material is imagewise exposed and developed to form an image, and this image is fixed by exposure to active light which sets the photosetting compound or composition. A condensation product of p-diazodiphenylamine with formaldehyde, a deriv. thereof, ethylene glycol di(meth)acrylate or the like is used as the photosetting compound or composition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photosensitive lithographic printing plate that does not require dampening water and has a silicone rubber layer as an ink repellent layer.

[Prior art]

In conventional planographic printing using the offset method, two types of surfaces with different surface chemical properties configured in an image shape are given functions of an image area (oleophilicity) and a non-image area (hydrophilicity), and the non-image area The ink repellent layer is created by supplying dampening water to form a water film.

This lithographic offset printing plate is currently most widely used because it has the advantage of being relatively easy to make, low cost, and capable of producing high-quality printed matter. However, since it is an unavoidable requirement to use diluted water, there are a number of problems caused by this. For example, ■ Adjusting the balance between water and ink is difficult and requires skill, which poses an obstacle to automation and labor saving of printing work. lol
Js", 65 jin"x -) 'L -k ツ1o
f2F-n J4 is applied and the horizontal paper ratio is high, ■ Paper expands and contracts with water and misregistration is likely to occur, ■ The shape of the halftone dots is distorted due to emulsification of ink, the ink adhesion becomes irregular, and the halftone dots There are problems with reproducibility, etc.

In order to fundamentally solve this problem, research began several years ago on lithographic printing using a silicone rubber layer as an ink-repellent layer without using washing water. Special Public Showa 114t-,2,? No. 041.2 Publication 11) - This is the first document showing the use of silicone rubber as an ink repellent layer, and since then, a mountain of patents have been published regarding photosensitive lithographic printing plates that do not require dampening water and have various configurations. . In such a lithographic printing plate that does not require dampening water, a photosensitive layer and a silicone rubber layer are provided on the support. In order to
It is necessary to choose a solubilized photosensitive substance. An example of a lithographic printing plate with such a structure that does not require dampening water is available at Tokko Akira Otsu-/A.
It is shown in the O'll1 publication. With this plate configuration, the photosensitive layer in the exposed area is photodecomposed, becomes soluble in the developer, and is removed together with the upper silicone rubber layer, so the exposed area becomes the image area and no dampening water is required. It becomes a lithographic printing plate. However, the previously dissolved photosensitive material that retains the silicone rubber layer in the unexposed and non-image areas retains its photosensitivity even after development, and cannot be exposed to bright light or indoor fluorescent lights. Change. On the other hand, printing plates may come into contact with organic solvents similar to developing solvents during plate cleaning or contact with printing ink during the printing process, and in this case, it is difficult to determine how good image reproduction is obtained up to the developing process. However, since the photosensitive layer has been solubilized by re-exposure since then, it is attacked by the active solvent and falls off together with the silicone rubber layer forming the non-image area, resulting in poor IIL+1 image reproducibility on the printing plate. It has a fatal flaw that it cannot be maintained.

In order to solve this problem, a method of exposing, developing, and heat-fixing a negative planographic printing plate that does not require water (0 Kaisho Tata-Otsu 0
9-ri No. 7 and JP-A No. 1983-] 9 Utah, 1&) and a method of base treatment after exposure and development (JP-A No. 1989-7)
-2037G No. 0 public trunk) is disclosed in Kawa-. However, the former method requires a heat treatment device, and the latter method requires a two-bath treatment process since it is wet-processed after development, which complicates the processing equipment.

[Purpose of the invention]

Therefore, the object of the present invention is to develop a photosensitive printing plate that does not require dampening water and has a structure in which a photosensitive layer and a silicone rubber layer are coated on a supporting body. +
sex,! [Structure of the Invention] As a result of intensive study, the present inventors have found that
In a photosensitive lithographic printing plate that does not require dampening water, the R luminescent layer contains a photocurable compound or composition, and after image exposure and development, it is exposed to actinic light in an amount greater than the image exposure amount, or to the image F layer.
We have now completed the present invention by discovering that the above object can be achieved by exposure to active light Q of a wavelength different from that used for the light used.

This is a water-free photosensitive lithographic printing plate which is formed by coating a photosensitive layer containing a diazide compound, a photocurable compound or composition, and a silicone rubber layer in this order.

The photosensitive lithographic printing plate of the present invention includes a photocurable compound or composition 1 having sufficiently lower sensitivity than the orthoquinonediazide compound in the photosensitive IN containing the orthoquinonediazide compound, or a photosensitive wavelength range of the orthoquinonediazide compound. It is assumed that a photo-Fφ-forming a compound or composition having a photosensitive wavelength range p is added to the foil 8. For this reason, the image can be made uniform by screening the image with sufficient active light μ)1 to cure the photocurable compound or composition after development. It is.

Photocurable compounds or compositions that can be used for Fudou 114 are broadly divided into photocurable 15 ((type) and photocurable compositions. compounds containing, for example, formaldehyde condensates of p-diazodiphenylamine and their derivatives; Koji4keika type, such as vinyl senate, β-cinnamoyloxyethyl methacrylate homopolymer, and copolymer, unsaturated polyester obtained from condensate of p-phenylenenoacrylic acid and diol.

There are those containing a photosensitive 411 polymer having a near ff bond. The sensitive wavelength range of diazo group or azide group is usually 0.
- It is similar to that of quinone cyanide, and the sensitivity cannot be adjusted freely, so it is not very suitable for the present invention, but it can be used by adjusting the ratio of their amounts.

Examples of photopolymerizable types include compositions containing monomers containing double bonds in terminal groups, such as ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxyethyl(meth)acrylate, Hydroxynorovir (meth)acrylate, glycidyl (meth)acrylate, /-ripday-λ-
A series of acrylic acid esters such as hydroxyethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, trimethylol-p-n-tri(meth)acrylate, methacrylic is an ester, methylenebisacrylamide, N-methylolacrylamide, methoxy Acrylamide derivatives such as methylacrylamide are suitable, and those containing two or more double bonds at the terminal -jil are particularly effective.

Of course, these monomers may be useful as crosslinking agents between polymers.

Among these photocurable compounds or compositions, the photocuring speed of crosslinked and polymerized types containing photosensitive double bonds can be freely changed by selecting a sensitizer for them, but if too much Using a sensitizer is ii! ++ This is not a preferred embodiment when considering separating the image forming process and the fixing process.

Therefore, when the photosensitive wavelength range of the orthoquinone diazide compound and the photosensitive wavelength range of the photocurable compound or composition are similar, the sensitivity necessary for the image forming process (i.e., the photosensitive layer becomes soluble in the developer) It is preferable to adjust the photosensitive layer so that the sensitivity (sensitivity) is 70 times or more the sensitivity required for the fixing step.

The amount of the photocurable compound or composition contained in the photosensitive layer of the photosensitive lithographic printing plate of the present invention is desirably smaller than the amount of the orthoquinone cyacyto-9 compound. In general, it is appropriate to use C, 20 to 700% by weight and less than 1'% by weight of the orthoquinonediazide compound.

If it is less than this, the desired effect will not be achieved by HH.
If θ0 weight: t% or more, photocuring of the photocurable compound or composition proceeds, and development with a solvent-based developer becomes extremely slow, which is not preferable.

The orthoquinonediazide compound used in the present invention is
It is a compound having a di-diazo-/-naphthol structure in its molecule, and is usually obtained by reacting a sulfonic acid derivative, such as sulfoctetralide, with a compound having a hydroxyl group or an amine group.

These orthoquinonediazide compounds may have any skeleton structure as long as they are compatible with the photocurable compound or composition to be added.

The amount of the orthoquinonediazide compound in the photosensitive composition may be such that it is present in an amount sufficient for image formation with respect to the imaging solution used. Generally, a value of 0% or more is appropriate.

By the way, in the case of conventional photosensitive lithographic printing plates for offset printing, a similar idea has been adopted, that is, by mixing a photocurable compound or composition with an orthoquinone diazide compound j, a high printability of a positive photosensitive lithographic printing plate can be achieved. The targeted technology is disclosed in the Special Publication Showa Z-λ Otsu θ/Ko-No. In this method, a photosensitive printing plate equipped with a photosensitive layer containing a photocurable composition and an orthoquinone cyasito compound is imagewise exposed, developed, and the entire surface of the formed image trap is exposed to light to expose the photocurable composition. The purpose of this method is to produce a printing plate that is sufficiently cured and has excellent printing durability, and is at first glance similar to the present invention. However, the invention described in Japanese Patent Publication No. 3-2607 (hereinafter referred to as "known example") and the present invention are significantly different in the following points. First, the developer is different. The present invention is a photosensitive lithographic printing plate that does not require dampening water, and the outermost surface layer is served by a silicone rubber layer. On the other hand, a known example is a conventional photosensitive lithographic printing press using dampening water as a backing, and is not provided with a silicone rubber layer. By the way, the silicone rubber layer is actually a
Since it is essentially water-impermeable, it is extremely difficult to develop the lithographic printing plate of the present invention in an alkaline aqueous solution.Therefore, in the present invention, a solvent-based developer is used. In known examples for 1C, it is said that it is preferable to use a developer consisting of an alkaline aqueous solution, and in those examples,
In practice, a developer consisting of an alkaline aqueous solution is used. [lambda]th, the proportions of the photocurable compounds or compositions are different. In the present invention, as described above, only solvent-based developers can be used. For this reason, if the amount of photocurable compound or composition in the photosensitive layer is larger than that of the orthoquinonediazide compound, the photocured product will be formed in many layers, so it cannot be developed with a solvent-based developer. Therefore, in the present invention, it is preferable that the amount of the photocurable compound or composition is smaller than the amount of the photocurable compound or composition that is used for orthoquinonediazide.On the other hand, in the known examples,
Since an alkaline aqueous solution is used as a developer, it is not necessary to control Se1 of the photocurable composition so strictly. In this regard, the conventional claims of known examples include:
It is described that an orthoquinonediazide compound is used in an amount of 0.0 S-part by weight based on part by weight of the photocurable composition. Furthermore, in the examples of known examples, photocurable composition/
Orthoquinonediazide compound 0.0% based on weight part. ．． 25
~0.50 parts by weight is used, and the optimum value of the orthoquinone diazide compound is 0.
λ~0. It is stated as 1 part by weight. In this manner, the known examples positively state, contrary to the present invention, that it is desirable to use more photocurable compositions than orthoquinone diazide.

From the above, it is understood that the present invention and the present invention are clearly different in purpose, structure, and effect.

The silicone rubber layer used in the present invention includes -liquid room-temperature curing silicone rubber, two-component foil silicone, and in some cases, two-component addition reaction silicone rubber or Tokko Sho S-7.2g60. It may be a mixture of a room-temperature curing silicone rubber and a two-component addition reaction silicone rubber described in the publication, and any silicone rubber composition that forms an ink-repellent layer can be used.

The layer structure of the dampening water-neutral negative photosensitive lithographic printing plate of the present invention includes a support, a primer layer, a photosensitive layer, an adhesive layer, and a silicone rubber layer, which are stacked in this order. The adhesive layer can be omitted. The thickness of the layer is
The photosensitive layer is almost O1 left ~ 3φ? The silicone rubber layer can have a thickness of 80 to 'I f/yri', but from the viewpoint of tone reproducibility, the thinner the silicone rubber layer, the better, and from the point of view of printing and staining, a certain thickness is required. Yes, usually 2.0
~2.3 f/rrj is preferred. The thinner the primer layer and the adhesive layer, the better, as long as they are sufficient to exhibit their functions.

The developer for the negative-working photosensitive lithographic printing plate that does not require dampening water according to the present invention includes alcohols such as ethanol, isopropyl alcohol, n-propyl alcohol, methyl glycol, ethyl glycol, n-propyl glycol, n-butyl glycol, Aqueous solutions containing diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monozorobyl ether, diethylene glycol monobutyl ether, benzyl alcohol, etc. are preferred, and petroleum solvents that swell the silicone rubber layer, such as hexane, hezotane, isoparaffin hydrocarbons A mixture of a solvent and an alcohol may also be used.

〔Effect of the invention〕

According to the present invention, a negative-working photosensitive lithographic printing plate that does not require water and has excellent printing durability and solvent resistance during printing can be obtained.

〔Example〕

The present invention will be explained in more detail with reference to one example below. "%" in the examples indicates "M amount %".

Example/λ liquid type epoxy adhesive (Super Cemedine) A, B
Parts of λ and s of the combined solution were taken and dissolved in 93 parts of methyl ethyl ketone. The following adhesive solution was applied and dried on an aluminum plate that had been previously degreased in a conventional manner to produce an aluminum plate coated with a single layer of primer. The aluminum plate coated with a single layer of primer prepared in (1) in this way does not dissolve even when immersed in a developer or photosensitive J(q coating solvent mixture (methyl cellosolve acetate dimethyl ethyl ketone = 2:/mixture)). There was no.

On the aluminum support coated with a single layer of the primer obtained as described above, a photosensitive solution having the following composition was applied with drying oil:! i
It was coated to a thickness of t: / 097 m and dried.

Polyhydroxyphenyl 1-diazo/-naphthol-5-sulfonic acid ester obtained by condensation of acetone and pyrogallol (US 1 Ei% W 1 3 Otsu 3!
; Compound described in specification contract No. 709) B, 3 parts by weight p-phenylene diacrylic m varnish and l11. - dihydroxyethyloxycyclohexanone/:/η1 condensation polyester 3J parts by weight Victoria Pure Blue BOH (Odugaya Chemical) 0.7 parts by weight Methyl cellosolve acetate /, 20 *, fa part Methyl ethyl ketone Otsu θ Jutobe Next Shin-Etsu Chemical A solution of BM-Otsu 03 (N-β(aminoethyl)-γ-aminoprobyltrimethoxysilane)/3P' dissolved in 1 part of n-hebutane SOθl was added to Silane Cassilling Chii 11 manufactured by Co., Ltd. Coating on the above photosensitive layer
After drying, apply E4/T (-smooth type RT) to Shin-Etsu silicone.
70 parts by weight of Isopar G (EXXON)
750 (manufactured by Chemica 1) was coated with a dry stone so that two rings were formed. λ at 100℃
It was left to dry in a dark place overnight to complete curing. A negative film is closely attached to this photosensitive lithographic printing plate that does not require dampening water,
``After 30 counts of exposure using a Nuar printer, the photosensitive layer in the foggy light area and the silicone rubber layer on top of it were revealed by rubbing it lightly with an image pad for 7 minutes using a sandpaper impregnated with ethylene glycol ether. After removal, the unexposed areas, ie, the non-image areas, were left unaffected by any change and the Noricone Rubbers 1 to 4 remained as they were. A -third part of the waterless lithographic plate developed by the above method (300 counts of A+ on the glass surface of the above printer) [lR light was applied, and another -third part (B) was At the same 30 counts as Exposure 14, 1D:' is illuminated and the remaining - third part (C
) were completely exposed to no light. When the sample treated as described above was subjected to the same process as F4 and development, parts (A) and (C) did not change at all, but the photosensitive layer and silicone in part (B) did not change at all. It was found that the rubber layer was removed and part (A) was completely photofixed by exposure to 0θ counts.

EXAMPLE 1 An aluminum plate coated with a single layer of primer similar to Example 1 was prepared, and a photosensitive solution having the following composition was applied to the plate to a coating thickness of 7.0, and allowed to dry.

Polyhydroxyphenyl 1-diazo/-naphthol cinnamoyloxyethyl methacrylate 9:/copolymer of acrylic acid obtained by condensation of acetone and pyrogallol 11.3 Oki Aabe Victoria Pure Blue BOH (Odugaya Chemical) θ/ ]1-tailed methyl cellosolve acetate 720-tailed methyl ethyl ketone
1 part of θ weight Next, a silane coupling agent was applied to the same 45゛9 as in Example, followed by a silicone layer to obtain a photosensitive lithographic printing original plate that did not require water. Apply negative film to this,
After 30 counts of exposure using the printer described in Examples/Description, development was carried out with ethylene glycol motsubutyl ether. A pad was used for development in the same manner as in Example. A third of the obtained plate (A) was exposed to light for 500 counts on the glass surface of the printer, and another third of the plate (B) was exposed for 30 counts, the same as the exposure amount. , the remaining -third part (C) was kept completely out of the light.

When the sample prepared as described above was again subjected to the same process as development, parts (A) and (C) did not change at all, while the photosensitive layer in part (B) became soluble in the developer. The silicone rubber layer was removed. From this 1
．． ! It is recognized that the part (A) exposed to light for a long time was completely photofixed.

Example 3 Thickness 0. ．． The surface of a 2'l nm aluminum plate was grained using a nylon brush and a q00 mesh pumice stone-water suspension, and then washed.

Etching by immersing in 70% sodium hydroxide at 70°C for 60 seconds, washing with running water, neutralization washing with 1.20% nitric acid aqueous solution, and washing with water, followed by electrochemistry as described in JP-A-33-1.7307. surface roughening treatment, i.e. VA=/J, 7V,
VC=9. Electrolytic surface roughening was carried out using a sinusoidal alternating current of /V in a /% nitric acid aqueous solution with an anode special electricity amount of /20 coulomb/d, 1. Continued immersion in 30% sulfuric acid aqueous solution 1. After dismuting for 2 minutes at t and t'C, 7
% sulfuric acid aqueous solution to a thickness of 2.797 m.

The following photosensitive composition was applied to the substrate obtained in the above manner under dry conditions. ; It was coated and dried so that it became t/rrj.

Sudiazo/-naphthol-3-sulfonic acid ester of polyhydroxyphenyl obtained by condensation polymerization of acetone and pyrogallol (compound described in the specification of U.S. Pat. No. 3, No. 3, No. 709) '70 parts by weight p-phenylene diacrylic acid ester /:/Oki condensation polyester of and l Kudihydroxyethyloxycyclohexanone 3. 60 parts by weight of θNN methyl cellosolve acetate/20' TiC methyl ethyl ketone Next, a silane cassilling agent and a silicone rubber layer were applied in the same manner as in Example to obtain a photosensitive lithographic printing original plate that did not require dampening water. A negative film was brought into close contact with the film, and after 30 counts of AN light was applied to the film using the printer described in Examples/Description, development was performed using a development pad impregnated with ethanol. The obtained waterless lithographic plate was further heated in the above printer for S minutes.
It was exposed to light on the surface. This plate was treated with an ethanol solution, but no change occurred, confirming that it was sufficiently fixed.

Comparative Example The photosensitive lithographic printing plate described in Example/(Photocurable composition/orthoquinonediazide compound=/10.3) of Publication of Special Publication SHOTAM-ΩOtsu0/U was treated in the same manner as in Example/. A silane coupling agent and a silicone rubber layer were subsequently applied to obtain a photosensitive lithographic printing original plate that did not require dampening water. A negative film was attached to this, and after exposure was performed for 30 counts using the printer described in Examples/Description, development was performed using a development pad impregnated with ethanol. However, the expected image could not be obtained, and due to the curing of the photocurable composition, only an inverted printing plate was obtained, with the image area of the negative film becoming a non-image area that retained the silicone rubber layer.0 Procedure Appendix 1E Book 1, Indication of the Case 1981 Patent Temple No. 242896 2
, Title of the invention: Photosensitive lithographic printing plate that does not require dampening water 3, Relationship with the Ministry case requiring amendment: Name of applicant: (520) Fuji Photo Film Co., Ltd. 4, Agent: 5, Date of amendment order: Self Filing specification On page 4, line 7, ``exposed to fluorescent light'' was corrected by 1 to ``1-exposed to light from fluorescent light''.

Claims (3)

[Claims] (1) A photosensitive lithographic printing plate that does not require dampening water and is prepared by coating a support with a photosensitive layer containing an orthoquinonediazide compound, a photocurable compound or composition, and a silicone rubber layer in this order. (2) The photosensitive lithographic printing plate that does not require washing water according to claim 1, wherein the photocurable compound or composition is a photosensitive resin. (3) Fountain water-free photosensitivity according to claim 1 or 2, characterized in that the content of the photocurable compound or composition is less than the content of the orthoquinone diazide compound. XF version printing version.