JPS6123960B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a protective coating film cleaning agent,
In particular, the object is to provide a cleaning agent that can easily and completely remove a protective coating film provided on the surface of a lens. Lenses such as optical lenses are attached and removed during processing, but in order to avoid scratches on the lens surface, a protective coating is usually applied to the lens surface. As this protective coating, synthetic resin coatings such as vinyl chloride resin coatings and butyral resin coatings, paraffin wax, etc. are mainly used. After finishing work such as processing, it is necessary to wash and remove the protective coating film, and conventional cleaning agents for this purpose include methylene chloride, trichlorotrifluoroethane, 1,1,1-trichloroethane, trichloroethylene, and tetrachloride. Attempts have been made to use halogenated hydrocarbons such as ethylene. Among these, methylene chloride in particular has the features of strong dissolving power, low toxicity, non-flammability, and extremely high chemical stability, but these halogenated hydrocarbons alone do not have the expected cleaning effect. (easy and complete removal of the protective coating) is difficult to achieve. In order to solve this problem, various attempts have been made to add certain additives, but no fully satisfactory results have been obtained. In view of the above points, the present inventors have discovered that the inherent performance of halogenated hydrocarbons, particularly methylene chloride,
As a result of extensive research with the aim of achieving better cleaning effects by adding relatively small amounts of other substances without interfering with its properties, we have developed a hydrophobic surfactant for halogenated hydrocarbons. The present invention was completed based on the discovery that the above object can be achieved by adding . The present invention will be explained in detail below. The halogenated hydrocarbon used as the main ingredient in the present invention includes methylene chloride, trichlorofluoroethane, 1,1,1-trichloroethane, trichlorethylene, tetrachlorethylene, etc. Among these, chlorinated hydrocarbon Methylene is particularly preferred. Hydrophobic surfactants added to the above halogenated hydrocarbons include mono- or polyoxyalkylene alkyls such as mono- or dioxyethylene palmitylamine, mono- or dioxyethylene laurylamine, and mono- or dioxypropylene laurylamine. Amine, mono- or dioctyl phosphate ester/2-ethylhexylamine neutralized product, monooxyethylene laurylethylamine/
Examples include neutralized products of saturated aliphatic amines and organic acids, such as neutralized caprylic acid and neutralized monooxyethylene laurylamine/2-ethylhexylic acid. Furthermore, in the present invention, excellent effects can be obtained by adding monocarboxylic acid esters such as ethyl formate, methyl acetate, ethyl acetate, n-butyl acetate, methyl propionate, and ethyl butyrate to the hydrophobic surfactant. I can do it. The blending ratio of the above additives to the halogenated hydrocarbon is 0.01 to 10% by weight in the case of hydrophobic surfactants.
(preferably 0.1 to 5% by weight), in the case of monocarboxylic acid esters 1 to 50% by weight (preferably 10% by weight)
~30% by weight), and if the amount of these additional components added is too small, sufficient cleaning effect will not be obtained. Not only is this effect ineffective, but it is also economically disadvantageous and flammable. In addition, it is desirable to add a stabilizer to the protective coating film cleaning agent obtained in this way, if necessary, and the stabilizer includes epoxides such as propylene oxide and butylene oxide, and amines such as diisopropylamine and isopropylamine. Examples include nitroalkanes such as nitromethane and nitroethane, and alcohols such as methanol and ethanol. By using the cleaning agent of the present invention, the protective coating film (synthetic resin paint, paraffin wax, etc.) on the lens surface can be completely removed with a relatively simple cleaning process, reducing cleaning costs. It has the advantage of being low and economical. Next, specific examples will be given. Examples (Experiment Nos. 1 to 16) A vinyl chloride resin protective paint (white) was applied to 50 photographic concave and convex lenses (30 mmφ) and left for 1 hour.
The 50 lenses with the protective coating were placed in a cleaning basket, and then the cleaning basket was sequentially placed in a four-tank ultrasonic cleaner for cleaning, and the quality of the finish was visually judged to determine the pass rate. The cleaning time was 1 minute for each tank, and the cleaning agent listed in the table was used for the first tank, and methylene chloride containing stabilizer was used for the second, third, and fourth tanks. The results were as shown in the table. However, Experiment Nos. 1 to 6 show the present invention, and Experiments No. 7 to 11 show comparative examples.

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Claims (1)

[Claims] 1 A hydrophobic surfactant, which is a neutralization product of a saturated aliphatic amine and an organic acid, is added to a halogenated hydrocarbon.
A protective coating cleaning agent for lens surfaces containing 0.01 to 10% by weight.