SU523381A1 - Photopolymerizable composition - Google Patents

Description

(54) PHOTO-POLYMERIZED COMPOSITION

one

The invention relates to a technology for the manufacture of printing plates for high-grade, type-printing, flexographic and screen printing, and can be used in the printing industry and other branches of the national economy.

A photosensitive composition is known, consisting of oligoester acrylates, acrylic monomers, solvent and photosensitizer.

However, the known composition has a low sensitivity and a large graphic image distortion on the form.

The purpose of the invention is to develop a photosensitive composition that enhances its photosensitivity while achieving high quality photopolymer printing plates and reducing graphic and dimensional distortions.

For this, according to the proposed method, trichloroethyl phosphate or triethylene glycol or triethylene glycol bis (hydroxyethyl) glycol ether di-p-cyanoethyl ether is used as a solvent in the composition in the following ratio of components, wt. am: a, m-methacryl (diethylene glycol) phthalate and / or

a, w-methacryl- (bis-90

80-diethylene glycol) -phthalate 6.5-14 methyl methacrylate trichloroethyl phosphate or di-p-cyanoethyl ether triethylene glycol

2,5-5 or triethylene glycol bis (hydroxyethyl) glycol ether

benzoin 0.5-1

Example 1. Make a composition of the following composition, wt. h .: Oligoether acrylate - a, co-methacryl- (bis-ethylene glycol) -phthalate (type MDF-2) 80-90

Monomer methyl methacrylate 6.5-14 Photosensitizer -

benzoin 0.5-1

Triethylene glycol bis- (hydroxyethyl) glycol ether3-5

After thorough mixing and decontamination, the composition is poured into the cavity of the forming-copying frame formed by two glasses, thickness and spreading limits, and the negative is glued to the inner side of one of the glasses, and exposed on both sides to form the base and the printing elements on it.

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Exposure is carried out with LUF-80 ultraviolet lamps at a distance of 10-12 cm for 2-3 minutes to form the substrate and 6-7 minutes to form the printing elements.

After exposure, the non-photopolymerized liquid is drained, the frame is disassembled and the photopolymer form is purified with an aqueous-acetone (1: 1) solution.

The finished photopolymer printed form is characterized by clear edges of the printing elements, high resolution (more than 160 lines / cm), high evolving ability (less than 50 µm), trapezoidal profile of the printing elements, size distortions of not more than 0.001% on the base 12 5 cm

In the absence of triethylene glycol-bis- (hydroxyethyl) -glycol ether, the necessary quality of photopolymer forms is provided with a base exposure time of 5-6 minutes and a time of formation of the printing elements up to 25 minutes with a large dimensional distortion (+ 0.05-0.09%) .

EXAMPLE 2 A composition is made that is different from the composition of Example 1 by using as an additive trichloroethyl phosphate in the same amount.

With greater sensitivity, dimensional distortions of photopolymer forms do not exceed ± 0.001% on the same base. The exposure time for the formation of smallpox is 3-4 minutes, and for the formation of printing elements is 8-10 minutes.

Example 3. Make a composition of the following composition, wt. h .: Oligoether acrylates: a, (o-methacryl- (didthylene glycol) -phthalate (type MDF-2) 60-67,5

a, sh-methacryl- (bis-ethylene glycol) phthalate (type MDF-1) 22.5-25.0 Monomer - methyl methacrylate7-9

Photosensitizer -

benzoin 0.5-1

Di-p-cyanoethyl ester

triethylene glycol 2,5-5,0

High quality photopolymer form according to such characteristics as the profile of the printing elements, resolution, and highlighting ability, dimensional distortions

523381

(0.0054-0.0008% based on 12.5 cm) is obtained when the formation of the printing elements is 7-8 minutes.

In the absence of triethylene glycol di- (p-cyanoethyl ether), the exposure time of the base is 3.5-4 min, and the formation time of the printing elements reaches 25 min. The dimensional distortions are 0.05-0.007% on the basis of 12.5 cm.

Thus, the introduction of tri-ethylene glycol di-cyanoethyl ether and triethylene glycol-bis (oxyethyl) glycol ether into liquid photopolymerisable compositions based on oligoether acrylates of trichlorophosphate di-p-cyanoethyl ether

leads to increased sensitivity and reduced graphic distortion, which speeds up the manufacturing process of printing plates, reduces power consumption and improves the quality of printed plates or form models.

Claims (1)

1. Auth. St. No. 255773 class G 03c 1/68; 1968