SU591797A1 - Photosensitive material - Google Patents

Description

(54) LIGHT-SENSITIVE MATERIAL

one

This invention relates to photosensitive. materials that can be used to record information, as well as photographs in UV rays,

A photosensitive material is known that is a heterogeneous system, including a cellulose base and a photosensitive compound - a derivative of pyridine (nctroeneol-arbitrary, and fSK is also unsubstituted or mixed pyridonic or pyrimidium salts) fl

Lime photosensitive material has a number of significant drawbacks: the resolving power of these materials is limited by the heterogeneity of the entire system as a whole, their photosensitivity in the UV spectrum is small.

In addition, the image image on these photosensitive materials is low, for visualization of the image in some cases additional chemical and photographic processing is required, the materials are difficult to manufacture (in particular, photographic darkness is required), expensive and scarce materials are required.

reagents (organic dyes, nitrobenzylproduct).

The aim of the invention is to increase the photosensitivity in the ultraviolet spectrum and. increase the resolution of the photosensitive material.

Goal v is achieved by using a base and photosensitive compound, pyridine or a pyridine derivative, in the form of a homogeneous system.

The image on the photosensitive material based on the complex compound of cellulose with pyridine or its derivatives remains for a long time and does not disappear soon after exposure as is known for many materials forming the visible image during the exposure process (in particular, photochromic ones). The recording is chemically and thermally stable — erasing the recorded information until it was completely destroyed. It was not possible to carry out either thermal (experiments were carried out up to 2OO s) or chemical treatment (treatment with acids and alkalis). An important feature of the material is that the processing of the cellulose base with pyridine or its derivatives can be carried out not only in solutions, but also in vapors of these substances. Therefore, in a continuous recording process, for example, in recording devices, the treatment with pyridine vapor (or its derivatives) of conventional paper (to give it sensitivity) can easily be carried out directly by exposure. Thus, a photosensitive material based on the complex compound cellulose with pyridine (or its product) has several advantages over the known ones: it is a photosensitive material that is homogeneous, which provides a higher resolution (simple, easy to use, can be obtained in any desired physical form (film, paper, tissue) is a more practical material, apparently the image obtained on such material remains for a long time, and does not disappear shortly after exposure. The chromatographic paper is treated with pyridine for 30 minutes, washed with distilled water for 2–3 minutes and dried, the exposure is made with a PRK-4 mercury-quartz lamp (at a distance of 29 cm from the source) with an intensity of 7 5x10 4i). With exposures of 10 seconds and more, a yellow color appears on the exposed areas, the optical density of which increases with increasing exposure time. The processing time of paper pyridine can vary widely. Depending on the processing conditions of pyridine (processing time and concentration of pyridine), characteristic curves were constructed, on the basis of which the photographic properties of the material were determined. Data are given 3 tab. 1. As follows from the table. 1, a change in the processing time of pyridine from 1 minute to 16 hours does not significantly change the photosensitivity and other photographic properties of the material. Dilution of the pyridine solution (1: 3) leads to a decrease in sensitivity, contrast ratio, useful exposure interval. For practical use, treatment with pyridine can be recommended from 1 to 30 minutes. Anopogical results were obtained when exposing the pyridine pyramid and writing paper, as well as MajKibix cotton fabrics, washed from finishing agent in mildew soda solution, for 40 min. Since the shelf life of recorded information is an important property of photosensitive materials, the change in photographic characteristics of the visible image from the shelf life for materials (in paper form) based on cellulose and pyridine complex compounds has been determined. The data presented in Table. 2. Photographic properties of the material obtained on the day of exposure (storage period of days) are taken as initial. Thus, from example 1 it follows that the complex combination of cellulose with pyridine can be used as a photographic material. By varying the processing conditions and, accordingly, the concentration of sorbed pyridine, the photographic properties of the material can be somewhat changed. EXAMPLE 2. In order to clarify the possibility of obtaining film types of materials by this method, the photosensitivity of cellulose triacetate + pyridine complexes was studied. Cellulose + pyridine (based on cellophane). For this, the triacetate film (in the form of a 35 mm OT-14 base coating) and cellophane were treated with pyridine for 16 hours, washed with water for 2-3 minutes, dried and exposed to the full spectrum of the PRK-4 lamp. Based on the experimental data, characteristic curves were constructed and photographic properties were determined, which are listed in Table. 3. As follows from the table. Pencil materials have a lower light sensitivity than materials based on paper, however, if necessary, the use of film materials can be used by readers. PRI me R 3. To clarify the possibility of using the complex compound as a photographic material: Cellulose with coi-picoline Chromatographic paper was processed for pro-. aqueous pyridine - 3s-picolin. The treatment is carried out in the light at a komiata temperature. After processing, the paper is washed with a min water and dried. The processing time and the concentration of picolin were varied in order to study the effect of sorptive C-picoline amounts on the photographic properties of the material. The dried material is exposed under the conditions specified in Example 1 - As a result of exposure to the irradiated areas of the material, a yellow coloration appears, the optical quality of which increases with exposure; Optical density of unexposed materials is zero. According to the results of exponents of samples with different conditions of treatment with at-picopin, characteristic curves were constructed, on the basis of which the photographic characteristics of the cellulose material, β-picolin, were determined. In tab. 4 shows these characteristics, depending on the processing conditions of the Cyclosex chain with oi-picoline.

As follows from the comparison of the data table. I. and tab. 4, photosensitivity in materi al ale treated with oh ‑ picolin is significantly higher, but higher than when processing the same paper with pyridine.

Change in the photographic characteristics of the visible image from; its storage time for the material, cellulose + oi-picolin 20

(treatment In gf, nickeline 1 min) are given in table. 5. Notes

(30 min treatment with pyridine)

The data indicate tioo the possibility of using the complex compound of cellulose with a pyridine derivative-C C-picoline as a photosensitive material.

Thus, from examples 1–3 it is said that the ком -complex compounds of tsepupozy with pyridine (or its functional) can be used in various physical forms (paper, film) as a photo-material that is sensitive to the UV spectrum. The method of obtaining them is simple, economical and convenient to operate. The material is homogeneous, does not require a step, which ensures high resolution. By varying the traction end of sorbed pyridine (or its derivatives), one can change the photographic properties of the material. The visible image on the resulting photosensitive complexes / is preserved for a long time, and does not disappear immediately after exposure.

Table

and c a 2

1.5

0.22

1.10 Jjx - useful interval of exposures. U is the average gradient, otA is the relative photosensitivity, t is the exposure time needed to reach D 0.2 +1.

Table 3