The method of producing monoblastic on steel base

 

(57) Abstract:

Use: in the production of offset printing plates. The inventive surface of the steel plate is subjected to electrolytic degreasing. Then activate sequentially 5.0% solution of sulfuric acid and 0.2% solution of oxalic acid. Carry out electrochemical plating. Dried and put photosensitive layer.

The invention relates to the printing industry, namely, the method of obtaining monometallic plates on the basis of carbon steel for offset printing.

A known method of producing monoblastic for offset printing, comprising a steel strip degreasing, washing, electrochemical plating, rinsing, application of the copy layer and drying in a high-frequency electric field [1]

The disadvantage of this method is the use of a steel tape and a high-frequency electric field. The closest analogue is the way to get monoblastic for offset printing, comprising degreasing the steel plate in the alkali solution, the chromium in the electrolyte to the thickness of the chromium layer is 1.0 μm and the copy application layer [2]

Weeks is a result of the proposed method is to increase the shelf life of the plates, the decrease in the dissolution rate of the steel base and increase adhesion with the photosensitive layer.

This technical result is achieved in that in the method of producing monoblastic on a steel framework, including degreasing in alkaline solution, electrochemical plating, and coating the photosensitive layer according to the invention, before application of the photosensitive layer, the surface of the steel plate are sequentially subjected to electrolytic degreasing, chemical activation of 5.0% solution of sulfuric acid, and then in 0.2% solution of oxalic acid for 30 to 35 seconds, and electrochemical plating with washing the plates after each treatment, followed by drying over 172 min at a temperature 90-91oC.

Holding dual decamerone (sulfuric acid solution, and then with a solution of oxalic acid) can reduce the speed of the solution and to get more active surface for adhesion of the metal from the photosensitive layer.

Example.

According to the claimed method of monoblastic produced from carbon steel sheet, on the existing galvanoni, which greatly simplifies the process.

After activation of the surface is performed chromium plating to thickness n 1 μm, conducted after each stage is provided by rinsing plates in cold water, then hold the drying plates for 172 min 90-91oC and applied to the surface of the photosensitive layer.

The proposed method allows to obtain monoblastic where whitespace element is the very basis, and printing zagubiony the photosensitive layer.

The advantage of this method compared to known is that upon receipt of bi - and tri-metal offset plates to protect steel from corrosion and for good adhesion with copper coating, but when going to the proposed method, such as copper plating, Nickel plating is missing, which gives significant savings in non-ferrous metals, energy, chemicals, makes the process environmentally friendly, does not require additional process equipment.

The method allows the use of sheet material. The resolution obtained monoblastic not less than 200 l/see

Plate obtained the claimed method meets all the requirements monoplotting on a steel base.

The method of producing monoblastic on a steel framework, including degreasing in alkaline solution, electrochemical plating, and coating the photosensitive layer, characterized in that before applying the photosensitive layer surface of the steel plate are sequentially subjected to electrolytic degreasing, chemical activation of a 5% solution of sulfuric acid, and then in 0.2% solution of oxalic acid for 30 to 35 seconds and electrochemical plating with washing the plates after each treatment, followed by drying for 17 2 min at 90 91oC.

 

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