Bath liquid for black-and-white negative film ultrafine particle development and developing method

Abstract

The present invention relates to a bath solution and a developing method for black-and-white negative film ultrafine particle development. In order to solve the problem of poor development stability of existing ultrafine particles and reduced sensitivity, the bath solution is A solution prepared from the following raw materials in weight ratio: Sodium sulfite crystal 240-300, o-phenylenediamine 2-10, potassium metabisulfite 30-35, appropriate amount of water. The raw material of liquid A also includes 1-4 parts by weight of mitole, and the consumption of potassium metabisulfite is increased by 5-10 parts by weight. The water is 1000 parts by weight of normal temperature water after boiling for 2-7 minutes. The developing method is to first immerse the negative film in liquid A for 5-8 seconds, and then immerse it in the developing solution; for the negative film that needs to increase the sensitivity to a greater extent, first immerse it in the liquid A described in claim 2, and then immerse it in the developing solution. The bath solution and developing method of the present invention can not only maintain and improve the sensitivity in the development of ultrafine particles, but also produce better effects in high-quality development, and have good stability, and can significantly improve the effect of ultrafine particle development .

Description

technical field [0001] The invention relates to a negative film developing agent, in particular to a bath liquid for black and white negative film ultrafine particle development and a developing method. Background technique [0002] Leica photographer Luis Castaneda once said: "People often ask me why I still shoot black and white photos when the color market is popular. My answer is that when color pictures can help you make money, it is just a coin in your pocket. , and black and white pictures are the spiritual food for your creation." [0003] Black-and-white photography has been with people for a century and a half. Today, the digital color photography that floods the market and is considered fashionable still cannot replace black-and-white photography. For a color work, the beholder often sees benevolence and the wise see wisdom, because consumers with certain artistic accomplishments have their own unique views on color and its application. But in front of a high-qu...

AI Technical Summary

Problems solved by technology

The commonly used formula for ultrafine particles is DK-20. Although it is widely recommended, it is rarely used, because although it can obtain the effect of ultrafine particles, there are still several difficult problems: 1. During the development process, the negative film will produce two-color gray Fog; 2. It will reduce the sensitivity of the negative film by 30%, what's more, it can't develop the underexposed negative film and below 20 degrees, and the stability is difficult to control