KR100398801B1 - A daylight Litho Photographic Film and method of manufacture therof - Google Patents

Abstract

The present invention is a printing plate film having a high resolution dot and high contrast photo characteristic in the developing and fixing process by using a scanner to enable reproducibility of image formation and to be transferred to a printing transfer plate for high quality printing. By increasing the content of silver chloride to 100% to increase the production of fine particles, characterized in that the production of bright green photo emulsion consisting of a fine particle square of the average particle size of 0.05㎛ ~ 0.08㎛.

Description

A daylight litho photographic film and method of manufacture therof}

The present invention is a printing plate film having a high resolution dot and high contrast photo characteristic in the developing and fixing process by using a scanner to enable reproducibility of image formation and to be transferred to a printing transfer plate for high quality printing. It is.

Recently, in order to obtain photographic characteristics that can be exposed by ultraviolet rays, a photo emulsion with low sensitivity has been developed, and a photosensitive material for bright room printing plate which can be used under white light such as a fluorescent lamp which has been removed with ultraviolet rays has been developed. It became. The clear picture characteristics should be lowered so that the contrast value is 4 to 8, the maximum concentration is 3.8 or more, and the sensitivity value (log E) is 1.3 or less. Conventionally, in order to prepare a photo emulsion of a clear printing plate film, the silver halide ratio is 85 to 92 mol% of silver chloride and the average particle size distribution is 0.1 μm to 0.2 μm, so that resolution is lowered and light stability is unstable using silver bromide. In order to reduce the sensitivity of the photographic emulsion prepared as described above, a method of obtaining low-sensitivity and high contrast photographic properties by using a large amount of rhodium salt as an inorganic sensitizer is disclosed in Japanese Patent Application Laid-Open No. 56-125,734 And Japanese Patent Application Laid-open No. 56-149,030, but since light fog is generated under a fluorescent lamp, a compound of an organic sensitizer such as pinacrypt yellow is used in parallel. Examples include US Patent 2,271,229 US Patent 2,541,472, US Patent 3,035,917, US Patent 3,124,458, US Patent 3,671,254, and the like.

Conventional photographic emulsion production method is a method of producing photosensitive silver halide particles in a gelatin solution by a single injection method or a double injection method of a halogen salt solution and a nitric acid solution, US Patent 2,541,472, Photo Chemistry (Kang Tae Seung, Photographic Publishing Co., 1987) It is described in, and it is composed of mixed particles of silver bromide (AgBrCl) and has a problem of stability under high contrast, high resolution and clear light with an average particle size of 0.1 μm to 0.2 μm with a silver chloride ratio of 85 to 92 mol%.

The present invention aims to solve the conventional problem room technology, as described above, and to produce a photo emulsion for clear room printing plate excellent in high resolution, high contrast and stability.

In order to achieve the above object, the present invention increases the content of silver chloride to 100% to increase the production of fine particles, characterized in that the production of clear photo emulsion consisting of fine particles of average particle size of 0.05㎛ ~ 0.08㎛ .

1 is a scanning electron micrograph showing the particle size of the silver chloride contained in the clear printing plate film according to the present invention.

In the preparation of the photographic emulsion of the present invention, in order to form fine particles, magnesium chloride was added to the gelatin solution (A solution) and silver nitrate solution was added by single injection to form nuclei (Seed), followed by silver nitrate solution and sodium chloride solution. Was injected for 20 minutes by co-injection to produce fine particles of silver halide having an average particle size of 0.05 µm to 0.08 µm. Photosensitive emulsion is prepared by adding the excitability and additives. When applying the prepared photo emulsion, the film for printing printing plates for bright room produced by adding and drying the organic compound which is a sunscreen agent to the protective layer solution at the same time is manufactured with a photo emulsion having excellent stability in light in a bright room such as a fluorescent lamp. 1 is a scanning electron microscope (SEM) photograph showing the particle size of silver chloride contained in a clear printing plate for printing according to the present invention. By measuring and comparing with the reference scale it can be seen that the average particle size of silver chloride in the film for printing printing for clear room according to the invention is formed to 0.05 ~ 0.08㎛.

The present invention is described in more detail as follows.

Magnesium chloride was added to gelatin solution (A solution), and silver nitrate was injected to form a nucleus. Then, sodium chloride solution (C solution) and silver nitrate solution (B solution) were added by co-injection to form particles of 100 mol% of silver chloride. To remove the salt, the photographic emulsion is removed by conventional noodles or condensation (see US Patent 2,489,341, US Patent 2,618,556, US Patent 2,565,418, US Patent 3,241,969, US Patent 2,614,928).

After washing with water, the photographic emulsion is susceptible to sulfur sensitization, reduction sensitization and metal sensitization. Chemical sensitization can be used by mixing with sulfur, cerium, tin, hydrazines, gold, platinum and palladium compounds (see US Patent 1,623,499, US Patent 2,399,083, US Patent 2,278,947, US Patent 3,297,447, US Patent 3,297,446). Stabilization of Photographic Silver halide Emulision (Focal Press, 1974), U.S. Patent for the prevention of fog generated during the preparation of the emulsion and the stabilization of photographic properties during storage Stabilizers of organic compounds such as 2,694,716, US Pat. No. 2,886,437, US Pat. No. 2,839,405).

As an additive used in the photo-emulsion completed by the above process, the inorganic compound of the film-making agent uses a chromium salt, and the organic compound includes only formarin, glyoxal, 2.4-dichrod-6-hydrooxy-S-triazine, etc. Or mixed use (see US Pat. No. 3,288,775) and plasticizers include polyalcohol, glycerin, fatty acids and silicone resins (US Pat. No. 2,960,404, US Pat. No. 2,588,765, UK Pat. 955,061). Zinc and polymethyl methacrylate are used (see US Patent No. 2,992,101, US Patent No. 2,701,245), and the surfactant is polyethylene glycol, polystyrene glycol ester, polyoxymethylene oxide, or the like (US Patent No. 2,600,831, copper). 3,133,816, U.S. Patent 3,068,101) The antistatic agent is referred to as thymol-based polymer, etc. (U.S. Patent 2,861,056, U.S. Patent 3,206,317, U.S. Patent 3,428,451) The thickener is completed by adding various additives such as polyalkyl acrylate type, cellulose sulfide, etc. to the photo emulsion.

Since the printing plate for bright room uses ultraviolet light as a light source, ultraviolet light is scattered when exposed to a clear polyester base film, and in order to absorb it, a dye that absorbs ultraviolet scattering such as tatrazine is used. 3,533,794, US Patent 3,314,794, US Patent 3,705,805, US Patent 3,700,455 and the like.

The present invention is a throat coating method for a protective layer solution prepared by adding a dye capable of absorbing wavelengths of 340 μm to 430 μm to a photographic emulsion layer and a water-soluble gelatin solution, as described above, on a back film coated with anti-hay rayon. (Modern coating and drying technology (VCH plate, 1993), U.S. Patent 4,001,024) by coating and drying the two layers at the same time to produce a film for printing high contrast, high resolution, light fog safety and low-light clear printing.

<Example 1>

Manufacturing method of clear photo emulsion

A solution

1,020 ml of distilled water

9 g of bone gelatin

Magnesium chloride 0.34 g

3.6 g citric acid

Rhodium chloride 0.01% 6.7 ml

Solution B is made by dissolving 170 g of silver nitrate in 350 ml of distilled water and 52.6 g of sodium chloride in 340 ml of distilled water.

One minute after adding 2 ml of solution B into solution A while maintaining solution A at 37 ° C, inject B solution and solution C for 20 minutes while maintaining PAg 7.6 by co-injection method, and add 25 ml of 1 wt% benzotriazole for 10 minutes. Terminate after stirring.

After the temperature was lowered to 30 ° C. and washed with the above-described water washing method, 2,400 ml of distilled water and 171 g of bone gelatin were added, and 10% 20 ml of sodium chloride and 1wt% of sodium thiosulfate were adjusted to PAg 8.2 to the required photographic characteristics at 48 ° C. Mature.

Add the following additives to the finished photographic emulsion:

80 ml of sensitizer 0.1% pinaglift eldo

Stabilizer 1% 1-phenyl-5-mercaptotetrazole 30ml

25 ml of surfactant 1% polyoxyethylene oxide (2)

20 ml of 3% saponin

20 ml of matt 2% silica (particle size 2㎛)

5% polymethyl methacrylate (particle size 2.5㎛) 10ml

Softener 20% Glycerin 20ml

And the temperature was lowered to 35 ℃ to prepare a photographic emulsion.

The photo emulsion is applied and dried simultaneously with the protective layer solution so as to have a silver content of 2.5 g / m 2 on the back of the polyester film coated with anti-hareshon to prepare a photosensitive material for clear printing plate film.

<Example 2>

A protective layer solution was prepared by dissolving 35 g of bone gelatin in 1,000 ml of distilled water and adding UV absorbing dye tarrazine dye to each concentration of 0.4, 0.5, 0.6, 0.7, and 0.8%. 10 ml of oxal and 15 ml of 3% saponin were obtained, completed, and dried.

The sample was 1.3m high in fluorescent lamp, and after 5 minutes, 10 minutes, 15 minutes and 25 minutes exposure, it was developed, fixed and washed with water at 35 ° C. for 90 seconds in a developer for printing and printing of Korean Photo Chemicals.

Table 1 and Table 2 below show the photographic characteristics of the present invention by the above method.

<Table 1> Ultraviolet Shenshi Hermitory

<Table 2> Fluorescent Lamp Exposure Test

By adding a 100% silver chloride photosensitive fine particle photographic emulsion to the protective layer, a UV absorbing dye can be prepared to produce a high contrast and high resolution clear room photo film without light fog in the clear room.

Claims (3)

A clear printing plate film, characterized in that the nucleus is formed of magnesium chloride, and 100% of silver chloride is formed in a mean particle size of 0.05 µm to 0.08 µm by co-injection using a sodium chloride solution and a silver nitrate solution. High contrast, high resolution, and maximum particle size by the photoemulsion containing 100% of silver chloride, which is made of magnesium chloride and formed into average particle size of 0.05㎛ ~ 0.08㎛ by co-injection using sodium chloride solution and silver nitrate solution Method for producing a printing plate for bright room, characterized in that it has a concentration. The method according to claim 2, wherein the prepared emulsion is applied to the film to form a photo emulsion layer and to the protective layer is applied to the protective layer is applied a solution containing a concentration of 0.4 ~ 0.8% of the tarrazine dye in order to excel Method for manufacturing a printing plate for bright room.