The solution for the manifestation of monometallic offset printing plates

 

(57) Abstract:

The inventive solution for the manifestation contains a hydroxide of an alkali metal of 0.5 - 1.0%, salt of carboxylic acid - oxytrichloride or discoverphoto 0.1 to 5.0% and the water - the rest. As a salt of carboxylic acid solution contains, for example, salt doxycyclinebuy or oxytrichloride acid. table 1.

The invention relates to printing production, namely the technology of offset printing plates, and more specifically to a solution for the manifestation of monometallic aluminum printing plates with a positive photosensitive layer on the basis of ordinationand (ONHD).

For the manifestation of printed forms on the basis of ONHD use an aqueous-alkaline solutions. The most effective of these are solutions translesanas phosphate Na3PO4the solutions of sodium hydroxide (caustic lye) NaOH and the solution of acid sodium (sodium silicate) Na2SiO3[1].

Manifest solutions for modern pre-chuvstvennyh plates must meet certain requirements: to ensure the required accuracy of tonal image transfer, the hydrophilicity privatecustomer layer to the solution, to have a high buffer capacity, to comply with environmental standards. The above solutions in varying degrees satisfy these conditions.

The disadvantages of developing solutions based on translesanas phosphate are low buffer capacity, high wetting angle space form elements (poor hydrophilicity) and the need for long exposures in the copy process to ensure the required gradation image transmission. In practice, to reduce the time of exposure in phosphate solutions are often injected with sodium hydroxide. However, the corrosion rate of aluminium in such developers increases in 25-30 times.

Aqueous solutions of acid sodium as a developer unlike phosphate provide good hydrophilic properties of the surface and practically do not cause corrosion of aluminum (provided there is no free alkali). But at the same time, they have a low buffer capacity, require large displays and, furthermore, formed during operation of the developer silica gel complicates the treatment of wastewater.

Solutions of sodium hydroxide in comparison with the above are large in the developer depending on the concentration of the hydroxide of an alkali metal.

The disadvantage of developing solutions based on the hydroxide of alkaline metal (sodium or potassium) is a low hydrophilicity white-space form elements and corrosive effect on aluminum. Negative role of corrosion processes is the destruction of the anodic film on space stations form, the leakage of small image elements.

The invention aims to remedy these disadvantages, namely improving the quality of the solution for improving the physico-chemical properties of the printing form.

The problem is solved in that the solution for the manifestation of monometallic offset printing plates, mostly with the photosensitive layer on the basis of ONHD containing alkali metal hydroxide and water, according to the invention further comprises a salt of carboxylic acid - oxytrichloride or doxycyclinebuy in the following ratio, wt.%:

The hydroxide of the alkali metal of 0.5-1.0

Salt of carboxylic acid is 0.1 to 5.0

Water the Rest

P R I m e R 1. Take pre-chuvstvennuyu plate with a photosensitive layer on the basis of ONHD, combine slide and exhibit in the copy device metallised playback control scales.

Taxpayerfunded plate is placed in a processing unit in which it passes successively operation manifestations, washing, applying preservative coating and drying. Made thus printed form suitable for use in the printing machine.

The composition of the developing solution, wt.%:

Sodium hydroxide 0.5 to

Sodium citrate

trehzameshchenny 1,0

Water 98,5

Characteristics of the solution are presented in table (solution 4).

This solution can be used for the display of pre-chuvstvennyh plate-type UPA-1 and UPA-2 (TU 15-0463801-11-91). It provides sufficient hydrophilicity gap elements, which does not require additional hydrophilicity form any other solutions (the value of the wetting angle is 2 times lower compared to solution 3) and has a low rate of corrosion rate (4 times less than in the solution 3). The high stability of the photosensitive layer to this developer allows you to use it for both automated and manual (in a ditch) ways of manifestation (the latter is preferable). The accuracy tonal transfer raster and stihovi what I printed forms, as in example 1.

The composition of the developing solution, wt.%:

Sodium hydroxide 0,7

Sodium citrate

trehzameshchenny 1,5

Water of 97.8

Characteristics of the solution are presented in table (solution 5).

This solution can be used for the display of pre-chuvstvennyh plate-type UPA-1". "The UPA-2" and "Azazel". It has a high buffer capacity, provides good hydrophilicity white-space form elements and low corrosion rate, is designed for automated and manual methods of manifestation.

P R I m e R 3. The procedure for manufacturing the printing plate as in example 1.

The composition of the developing solution, wt.%:

Sodium hydroxide 0,7

Potassium-sodium tartrate 1,5

Water of 97.8

Characteristics of the solution are presented in table (solution 6). The purpose of the solution, as in example 2.

P R I m e R 4. The procedure for manufacturing the printing plate as in example 1.

The composition of the developing solution, wt.%:

Potassium hydroxide 0,7

Sodium citrate

trehzameshchenny 2,0

Water 97,3

Characteristics of the solution are presented in table (solution 7). The purpose of the solution, as in example 2. It is recommended to use dust, as in example 1.

The composition of the developing solution, wt.%:

Potassium hydroxide 0,8

Sodium citrate

trehzameshchenny 0,1

Water 99,1

Characteristics of the solution are presented in table (solution 8).

This solution can be used for the display of plate-type Azazel" in automated and manual methods of making forms. It ensures the preservation of existing on the surface of these plates under the photosensitive layer of hydrophilic film (the value of the wetting angle is 15about), economical from the point of view of consumption of chemicals (salt concentration is 10-20 times lower than in other compositions).

P R I m e R 6. The procedure for manufacturing the printing plate as in example 1.

The composition of the developing solution, wt.%:

Sodium hydroxide 1,0

Potassium-sodium tartrate 5,0

Water 94,0

Characteristics of the solution are presented in table (solution 9).

This solution can be used for the display of plate-type UPA-1 and UPA-2". It has a high buffer capacity, creates a strong hydrophilic film on space stations form (the value of the wetting angle is 15aboutrequires low exposures (avannah installations.

These manifesting solutions (table, solutions 4-9) have a high pH the pH, the greater the buffer capacity, create a hydrophilic film on a whitespace areas of the printing form, have little corrosive effect on aluminum (3-12 times less than 0.5% solution of sodium hydroxide) and provide the required accuracy of the gradation image transmission at low exposures. The stability of the photosensitive layer to these solutions is lower than that of the prototype, however, this value provides a sufficient safety signs (6-20 times during the duration of the manifestation forms 15-60).

The SOLUTION FOR the manifestation of MONOMETALLIC OFFSET PRINTING plates mainly with the photosensitive layer on the basis of ordinationand containing alkali metal hydroxide and water, wherein the solution further comprises a salt of carboxylic acid - oxytrichloride or doxycyclinebuy, in the following ratio, wt.%:

The hydroxide of an alkali metal - 0,5 - 1,0

Salt of carboxylic acid is 0.1 to 5.0

Water - The Rest

 

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