SU742859A1 - Form light-sensitive material - Google Patents

Description

(54) LIGHT-SENSITIVE FORM MATERIAL

one

This invention relates to ultra-sensitive mold materials for the manufacture of offset printing plates without moistening, which are used in the printing industry.

A photosensitive form material for the manufacture of offset printing plates without wetting is known, consisting of an aluminum substrate with a green surface, a photosensitive diazo resin, or p-diazodiphenylamine and a layer of high molecular weight polysiloxane without adhesion to a special ink of f 1J.

The disadvantage of such a material is the complexity of its design and manufacturing technology. Silicone As an anti-adhesive coating, the elastomer does not have sufficient mechanical strength, making it difficult to manufacture and store the printing form. The high electrification of the coating contributes to the contamination of the form with paper dust during printing,

The closest to the proposed is a light-sensitive plate material for the manufacture of offset printing plates without moisture,

consisting of a granulated aluminum substrate and a photosensitive hydrophobic layer based on chain polymers, for example butyl rubber or ethylene-propylene copolymer, and an aromatic diazide, for example 2,6-bis (azidobenzylidene) g-4methylcyclohexanone 2.

The disadvantage of this plate material is the complexity of its success, since the metal (aluminum) plates used in the manufacturing technology of the plate are prefixed by labor-consuming

15 by mechanical methods or with the use of gsshvaniki. In addition, the use of granulated aluminum does not provide a high resolution of the material and does not allow it to be used for printing on role machines. The process of applying and forming on the material of the photosensitive hydrophobic layer is of low technology: duration

25 drying is several hours, and the application of the layer cannot be carried out on a continuous tape basis using high-performance rotary machines. In addition to

However, butyl rubber, used as a hydrophobic polymer, imparting a single-layer photosensitive composition of anti-geoionic properties with respect to a special printing ink. In the printing process, the solvents that make up the printing ink swell and lose mechanical strength.

; The purpose of the invention is to simplify the technology of manufacturing the material and to obtain printed-technical properties of the printing forms.

; The goal is achieved by ijeM that the substrate of the forma material is made of polyester resin, for example polyethylene terephthalate, and Between the substrate and the photosensitive hydrophobic layer, the material additionally has an adhesive layer including a vinyl chloride copolymer with vinylplate, silicon dioxide with a particle size of 0.1-0.5 microns solvents, for example dibutyl phthalate, ethyl acetate, butyl acetate in the following ratio of components, wt.%:

Vinyl chloride copolymer

with vinyl acetate 0.5-5.0

Silicon dioxide with

particle size

0.1-0.5 μm0.4-4.0

SolventsEther

The proposed forma material. it is much simpler to manufacture, since it does not require granulation of the substrate, and the printing forms obtained from it possess improved printing and technical properties.

And e REM 1. An adhesive layer of the following composition is applied to the oriented polyethylene-phthalate film, wt%:

Vinyl chloride copolymer

5.0 Vinyl Acetate Silicon Dioxide

.4, O, 1-0.5 microns

Solvents (1: 1: 1 ratio): dibutyl ostaphthalate, ethyl acetate and butyl acetate

A desensitizing layer of the next remaining, wt.%, Is applied to the adhesive layer:

5,0 Butyl rubber 2,6-bis (4-azidobenzylidene) -4-methylcyclo, 15 hexenone Gasoline BR-1 Rest

The photosensitive solution is applied to the adhesive layer, dried at a temperature not exceeding 100 ° C. A layer with a thickness of 1.5-3.5 μm is exposed through positive mounting under mercury, etal-halogen lamps. After exposure, the material is developed in an organic solvent, dried, fixed on a form cylinder, and the print run is printed with a special ink without moistening the forms.

Example 2. Differs from Example 1 in that the composition of the polymer photosensitive composition as a polymer base instead of butyl rubber uses an ethylene-propylene copolymer containing up to 3% of any cyclic diene (for example, ethylidene norbornene) SKEPT-E (Mooney viscosity 70 ). . While the adhesive layer has the following composition, wt.%:

Vinyl chloride copolymer

0.5, with vinyl acetate Silicon dioxide with a particle size

0.4 0.1-0.5 μm Else Solvents The table shows the properties of ma-. material and printing plates made according to examples 1 and 2 and the known material.

Claims (2)

It follows from the presented data that the proposed mold material has the same circulation capacity as the known one, while the resolution and optical density of the line image is more high than the high tensile strength of the polyethylene terephthalate film (like aluminum), can be produced on based on role offset printing plates. The transparency of the polyethylene tape and the entire composition of the material as a whole allows the use of printed forms as positives or negatives - duplicates from the originals. Duplicates made can be used for contact photocopying. By combining duplicates from a dissected original of rolled-up paints of different colors, you can check the combination of inks of multicolor printing and color reproduction. This eliminates the need for a colorful sample. The invention of a photosensitive form material for the manufacture of offset printing plates without moistening, consisting of a substrate and a photosensitive hydrophobic layer based on chain-chain polymers and an aromatic diazide, characterized in that, in order to simplify the manufacturing technology and improve the printing-technical properties of printing forms, the substrate material made of polyester resin, and between the substrate and the photosensitive hydrophobic layer, the material additionally has an adhesive layer, including copolymer p vinyl chloride with vinyl acetate, silicon dioxide with a particle size of 0.1-0.5 μm and solvents with the following ratio of components, wt.%: Copolymer of vinyl chloride with vinyl acetate 0.5-5.0 Silicon dioxide with a particle size of 0.1-0 , 5 µm0,4-4,0 Solvents The Other Sources of information taken into account during the examination 1.Patent of France 1560414, cl. G 03 C, published 1969. 2. Authors certificate of the USSR 481016, cl. G 03 F 7/00, published 1975 (prototype).