Abstract: Disclosed herein are a color filter wherein an organic pigment is comprised of primary particles having an average particle size of 20 to 200 nm and a particle size distribution within .+-.35 nm and said organic pigment has a color difference of 5 or less when it is subjected to exposure at an illuminance of 100,000 lux or more for 100 hours or more under the condition of a surface temperature at 50.degree. C.; a color filter wherein the film of coloring matter in green has a ratio (T.sub.485 /T.sub.610) of the transmittance of 485 nm (T.sub.485) to that of 610 nm (T.sub.610 ) of 3.5 or less, the maximum transmittance of the film of coloring matter in green is 60% or more and said maximum transmittance is assigned a wavelength of 540 to 550 nm; and a color filter using a specific organic pigment as each of red, green and blue pigments.

Abstract: A process for producing an organic thin film comprising solubilizing a hydrophobic organic substance with a surfactant containing a ferrocene compound in an aqueous medium to form a micelle solution, and electrolyzing the micelle solution to form a thin film of the hydrophobic organic substance on an electrode. The ferrocene compound has the formula: ##STR1## G is hydrogen, methyl or ethyl, R.sup.4 is hydrogen, methyl or ethyl,m is a positive integer satisfying the expression0.ltoreq.k+m.ltoreq.10,Z is --O-- or ##STR2## R.sup.1 and R.sup.2 are identical or different and each is H, NH.sub.2, N(CH.sub.3).sub.2, CH.sub.3, CH.sub.3 O, OH or halogen,R.sup.3 is hydrogen or methyl,k is a positive integer satisfying the expression 0.ltoreq.k+m.ltoreq.10,n is a real number of 2 to 70, a is an integer of 1 to 4, andb is an integer of 1 to 5.

Abstract: Disclosed is a process for producing a ferrocenoyl derivative comprising the reaction of ferrocene derivative with monocarboxylic acid or dicarboxylic acid in the presence of a catalyst.The ferrocenoyl derivative obtained by said process is very useful as the intermediate product for various functional materials, among all, for the micelle forming agents (surfactants) in so-called Micellar Disruption Method or the intermediate product of it.

Abstract: Ferrocene compounds represented by the formula: ##STR1## wherein A indicates ##STR2## wherein X is --CH.sub.2 --, --O--, ##STR3## G is a hydrogen atom, a methyl group, or an ethyl group, R.sup.4 is a hydrogen atom, a methyl group or an ethyl group, and m is a positive integer satisfying the expression 0.ltoreq.k+m.ltoreq.10, Z is --O-- or ##STR4## and R.sup.1 and R.sup.2 are identical or different and each is H, NH.sub.2, N(CH.sub.3).sub.2, CH.sub.3, CH.sub.3 O, OH or a halogen atom, and R.sup.3 is a hydrogen atom or a methyl group, k is a positive integer satisfying the expression 0.ltoreq.k+m.ltoreq.10, and n is a real number of 2 to 70, a is an integer of 1 to 4, and b is an integer of 1 to 5. Also provided by the invention are surfactants containing said ferrocene compounds.