JPS6028655A - Developing liquid for lithographic plate using no dampening water - Google Patents

Abstract

PURPOSE:To improve developability and to increase developing speed by using a developing liquid contg. an org. acid. CONSTITUTION:A lithographic printing plate requiring no dampening water prepd. by coating a photosensitive layer contg. o-quinonediazide compd. and a silicone rubber layer on a substrate in this order is exposed and then developed using developing liquid contg. an org. acid. Useful org. acid may be any of carboxylic acid, sulphonic acid, and phosphonic acid, but, formic acid, acetic acid, propionic acid, n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid, methylethyl acetic acid, trimethyl acetic acid, capronic acid, enanthic acid, caprylic acid, 2-ethylhexanoic acid, peralgonic acid, etc. are preferred.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field-1] The present invention relates to an improved developer for lithographic printing plates that does not require dampening water.

[Prior art]

Is the silicone rubber layer an ink-repellent layer? 5ii L water-free lithographic printing plate, which is a negative-working plate (4) For example, on a photosensitive layer provided on a support and containing a l-gynonone azide compound, a preliminary layer is provided. A sensitized version was proposed in JP-A-56-80046.These versions are 11ri 7:'+P.
The plate is made in the same way as the S plate through the exposure and development process, but the developer may be one containing an organic solvent as the main component, as proposed in Japanese Patent Application No. 56-1 Roro 278-Yumi. , it has been proposed that the main component is water.1 Such a developer has the risk of flammability in an organic solvent system, and furthermore, i7J: 'yI! There is a drawback that the silicone in the non-image area may be damaged or damaged during imaging. This tr, (for rc,
In water systems, it is suitable for the working environment (not bamboo shoots,
It is preferable that there is less risk of scratches on non-image lines during development, but the development time is less than 100%. This tendency was remarkable, and there were drawbacks such as poor development.

[Object of the Invention] An object of the present invention is to improve these drawbacks and provide a developing solution that has a high development speed and is stable during development operations.

[Structure of the invention]

In the present invention, a lithographic printing plate that does not require dampening water is prepared by coating a support with a photosensitive layer containing an orthoquinone diazide compound and/or a silicone rubber layer after exposure.

This is a developer for lithographic printing plates that does not require dampening water, and is characterized in that the developer used to develop images contains an organic acid.

In the present invention, there are no restrictions on the method of developing a lithographic printing plate that does not require dampening water and has a latent image formed by exposure to light, but the following methods can be mainly used.

(1) Organic solvent: A method in which a mixture of an organic solvent and water is used as a developer.

(2) A method in which the plate is pretreated by immersion in a 41-organic solvent, and then water or water containing an organic solvent is used as a developer.

(3) A method in which water or water containing a solvent is used as a developer after basic treatment.

In any of these methods, the effect can be achieved by containing an organic acid in the developing solution.
In methods (2) and (3),! Jl! The effect is most noticeable when only water is used as the developing solution, and the ability to remove organic solvents during the developing process, where workers are most likely to be exposed to organic solvents, is advantageous from the perspective of the working environment. be.

Although it is essential that the developer of the present invention contains an organic acid, the following organic solvents such as water/O and O can be used as the developer.

As the organic solvent used as the developer in the present invention, hydrocarbons and rod solvents can be used individually or in combination.

As hydrocarbons, the following are generally used.

Aliphatic hydrocarbons (P/Y/, hexano, hegetane, octane, Aitzva-E, H, M, gasoline/.

kerosene, diesel oil, 1 heavy oil, etc.).

Aromatic hydrocarbons (+-luene, quinlenato).

Halogenated hydrocarbons (triclene, carbon tetrachloride, etc.)
.

As polar solvents, those shown below are generally useful.

Alcohols (methanol, ethanol, n-propanol, ingropanol, 3-7 togisibuknol, 3
-methyl-6-medki/butanol, diacetone alcohol nato).

Ethers (dioxane, tetrahydrofuran.

Methyl cellosolve, ethyl cellosolve, buter cellosolve, ethylene glycol diethyl ether.

Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol diether ether, diethylene glycol monobuter ether, triethylene glycol monomethyl ether,
ethylene glycol dimethyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol dimethyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, tetrahydrofurfurylano, etc.).

Esters (acetochu/acid methyl, aceto 1-ethyl ethyl acetate, methyl cellosolve acetate, ethyl, I+/-hyrosolve acetate, diethylene glycol acetate/1. monomethyl ether noethyl ether, ethylene glycol monobutyl ether acetate, diacetic acid Glycol, egul lactate, methyl propionate, ethyl propionate.

Dinotyl malonate, malonate ether, Kono1ri l'l
2-dimethyl, diethyl phosphate, dimethyl adipate, etc.).

Organic acid r11 weight ii added to these developers: %”-
Although it is effective at J and above, it is preferably at least 5 tons)φ.

In the case of an organic acid having a relatively small number of carbon atoms, good development can be achieved even with just one.

In the present invention, the i3iJ treatment Jj is performed by dipping the lithographic printing plate that does not require dampening water and on which the image Ii has been formed by exposure.
+! When water containing an organic acid is used on top of a developer, the above-mentioned hydrocarbons and polar solvents can be used alone or in combination as the pre-treatment liquid.

The organic acids used in the present invention are not limited to 1%, but include, for example, carboxylic acids.

Any of sulfoheptacic acid, phosphonic acid, etc. may be used.

Organic acids suitable for in'' are formic acid, acetic acid, and propionic acid.

n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid.

Methyl ethyl acetic acid, trimethyl acetic acid, caproic acid.

Inocabronic acid, α-methylvaleric acid, 2-ethyl-n-
These are alkanoic acids such as acetic acid, enanthic acid, calylic acid, 2-ethylhexyl acid, and pelargonic acid. Organic acids having other functional groups have a small effect on the photosensitive layer in the image area that has been exposed through the silicone layer of the printing plate, and
No effect on JL image quality.

It consists of water alone after base treatment. -1' Even when using a developer containing water as a main component, the above-mentioned organic acid can be added to the developer.

Its developability can be significantly improved.

In the present invention, by using a developer containing an organic acid, 9. The developability is greatly improved and the development speed becomes faster, and the effect r↓ becomes more pronounced as the amount of water in the developer increases.

As a result, one worker is not exposed to solvent vapor for a long period of time, and the risk of ignition can be reduced because water alone or a developer with a high content of water can be used.

The present invention will be described in more detail below with reference to Examples.

In addition, "part" described in the examples is "weight: 1 d part - 1
shows.

Example 1 Phenol formaldehyde resol resin (Sumishi Resin PC-1, manufactured by Sumitomo Duress) was coated on an aluminum plate (manufactured by Sumitomo Light Metal) with a thickness of 0.24 nm to a thickness of 27 r (after curing), and heated at 190°C for a filtration period of λ.・The following photosensitive composition was coated on the nipped substrate as a support, and heat treated at 120° C. for 2 minutes to form a photosensitive layer with a thickness of 2 μm.

(1) Partial ester of naphthoquinone-1,2-diazido-5-sulfonic acid tophenol formaldehyde novolak resin (degree of esterification 47% by IR method) 10
0 parts by weight (214,4'-diphenylmethane diisocyanate-1.
30 parts by weight (3) Dibutyltin dilaurate 02 parts by weight (4)
740 i parts of dioxane Subsequently, a silicone rubber composition having the following composition was spin-coated thereon and cured with moist heat at 120° C. and a dew point of 30° C. for 2 minutes to form a 2 μm silicone rubber layer.

A lithographic printing plate that does not require dampening water was prepared.

(1) Dimethylborisiloxane (molecular weight approximately 25,00
0° terminal hydroxyl group) 100 parts by weight (21 hinyl l-'J (sotyl ether ketoxime)
Nran 8 parts by weight (3) Dibutyltin diacetate 02 parts by weight (4) r
- Aminopropyltrimethquine 1 part by weight (5) Isopar E (manufactured by Exxon Chemical Co., Ltd., aliphatic hydrocarbon-based flame release) 1 soo parts by weight of a metal light lamp (manufactured by Iwasaki Electric Co., Ltd.) on a lithographic printing plate that does not require dampening water 1m using idle fin 2000)
At a distance of
2 with a 6 second full exposure at an illuminance of '.

A gradation negative film having 150 lines and halftone dots from 2 to 98 was vacuum-tightly applied to the wet [-2 water-less lithographic printing plate which had been fully exposed and subjected to HjJ as described above, and the above-mentioned film was passed through it. Using the Metalno Ride Lamp 6-,
A negative type that can form an image by exposing one curved image for 60 seconds from a distance R1F of 1m? ! +ii L water inflexibility・17
A printed version was obtained.

Next, base treatment solution (methylcarbyl)/-1 monoethanolamine = 100 parts/5', iRi
The above-exposed plate was immersed for 1 minute in a flat vat containing /1i7j (if part). After soaking, remove the base treatment solution adhering to the surface of the printing plate with a rubber skein. Next, apply a developer consisting of 5 parts by weight of n-butyric acid and 95 parts by weight of water to the printing plate and developing pad. Applying a pressure of 10 g/m2 and rubbing the plate for about 1 minute, 7 of the exposed area in one image
The silicone rubber layer is removed, and the photosensitive layer is exposed to Sj L to form an image area, and the silicone rubber layer remains firmly in the ζ area, which is exposed only to full surface light and forms a non-image area. , a printing plate was obtained that reproduced an image faithful to the negative film. This printing plate is then offset printed (Hamada Star).
Attached to.

20,000 sheets were printed using Toyo Ink's ``Ulto 70'' without using dampening water.Prints R1 were in very good condition without any stains.Also, no damage was observed to the surface of the printing plate. There wasn't.

Comparative Example 1 A lithographic printing plate that did not require dampening water and had an image-forming ability was produced as described in Example 1 and exposed to light.
0 weight 411 parts 15ffi parts).

Next, pour water on the plate and the current fS Kobanodo and apply a pressure of 10g between the two surfaces.
The plate surface was rubbed with /Cm2 for about a minute, but the silicone rubber layer in the exposed areas could not be removed.

It became a printed version that was impossible to print.

Example 2 The dampening process produced in Example 1 and the lithographic printing plate required 150
Image forming ability was obtained by exposing a gradation film having halftone dots from 2% to 98% of the line for 60 seconds at a distance of 1 m using the metal halide lamp used in Example 1 in a vacuum-tight Xi l- according to a conventional method. A negative type dampening 7 water-absorbent lithographic printing plate with ! I was. Next, the above-mentioned exposed foil plate was immersed for 1 minute in a vertical vat into which a pretreatment liquid (methylcarpitol) was poured at a rate of /1j71. After immersion, the plate and back were covered with a rubber siege and the ζ pretreatment liquid was removed using a sifter, and then a developer consisting of 5 parts by weight of propionic acid and 95 parts of water and 11:,':'dl was poured onto the plate and the JJI image vat. , When the surface bar 1 [J (applying ψII2 and rubbing the printing plate for about 1 minute, 1iJj image-wise exposure 7N) with a developing vat, the /1 cone rubber layer on the upper part is removed, and the image line M produced by the photosensitive layer. A printing plate was obtained which reproduced the completed image on the negative film L. Next, when this printing plate was printed under the same conditions as in Example 1, extremely good printed matter was obtained. .

Comparative Example 2 The dampening water-free lithographic printing plate produced in Example 1 was exposed in the same manner as in Example 2. 1 in the mold bat
Soak for minutes. After dipping, the pre-treatment liquid adhering to the plate surface and back surface was removed using a rubber squeegee, and then water was poured onto the plate surface and the development throat.The plate surface was rubbed for about 6 minutes at a surface pressure of 7 m2, but the exposed area The silicone rubber layer could not be removed, resulting in a printing plate that could not be printed.

Example To the lithographic printing plate that does not require dampening water and was produced in Example 1.

A gradation film having halftone dots of 98% from the 2nd line of 150 lines was vacuum-adhered according to a conventional method.

1m using the metalno-ride lamp used in Example 1
By exposing the plate to light at a distance of 60 seconds at an illuminance of 60 seconds, an I-Ga type lithographic printing plate that did not require dampening water and had an image-forming ability was obtained.

Next, pour Hyosei 1 acid onto the developing pad and apply a surface pressure of 10
When rubbed for 1 minute at a pressure of g/m2, the resin rubber layer in the exposed area was removed and the surface of the photosensitive layer was exposed (forming an image trading area). When this printing plate was printed with the same stripes fl as in Example 1 (11<), the printed matter had a halftone reproduction range of 5 to 95%, and was free of minute defects and defects caused by scratches caused by the development bat. Obtained.

Example 4 A lithographic printing plate that does not require dampening water produced in Example 1 was coated with a 150-line duplex film with halftone dots ranging from 2% to 98%, and vacuum 1L*1L was applied in accordance with a conventional method. Exposure was carried out for 60 seconds at a distance of 11 nm using the metal compound used in Example 1.A negative type lithographic printing plate that does not require dampening water and has the ability to form an image f'? C(!f k-
Next, this original plate was developed,
10 parts, butylcarpitol 40 ll'tl:
, place a developer solution consisting of "il, - + 40 parts of dithylcalhitol, 1 part of 2-ethyl-\.
When rubbing with m2 for 1 minute, the exposure γXt+ paste ml -7
The ml layer was removed to expose the surface of the photosensitive layer and form 7 image areas. When this printing plate was printed under the same conditions as in Example 1, a printed matter with a dot reproduction range of 2 to 98% and no minute defects or defects such as scratches caused by the development pad was obtained.

The dampening water-less lithographic printing plate produced in Example 1 was treated in the same manner as the actual M12 example to obtain a negative-working dampening water-less lithographic printing plate having image-forming ability. Next, this printed version.

20 parts by weight of Isopar H and Petyl Calhi l on the developing pad.
By pouring a developing solution consisting of 40 parts by weight of ethyl carpitol and 40 parts by weight of ethyl carpitol, the silicone comb layer in the exposed area was completely removed and the photosensitive layer was exposed to form an image area. When this printing plate was printed under the same conditions as in Example 1, a printed matter with a halftone dot reproduction area of 5 to 95% was not obtained. The scar that seems to be 8.U is merare.

Claims (3)

[Claims] (1) After exposing a lithographic printing plate that does not require dampening water, which is prepared by coating a photosensitive layer containing an orthoquinonediazide compound and a silicone rubber layer on a support in this order, in a developer for developing one image. A developer for lithographic printing plates that does not require dampening water and is characterized by containing no organic acid. (2) A developer for a lithographic printing plate that does not require dampening water as set forth in claim 1, wherein the content of organic acid is 1 to 100% by weight. (3) A developer for a lithographic printing plate that does not require dampening water according to claim 1, wherein the organic acid is an alkali/acid.