Abstract: This invention relates to a new class of pH sensitive indicator dyes useful as optical filter agents in photographic processes to protect a selectively exposed photosensitive material from further exposure during processing in the presence of incident light. Such dyes contain a phenolate group as the ring-closing moiety and are represented by the compounds ##SPC1##Wherein R is hydrogen, alkyl, aryl, aralkyl or alkaryl, R.sup.1 and R.sup.2 the same are hydrogen, chloro or nitro, and R.sup.3 is hydrogen, carboxy, sulfonamido, sulfamoyl, or alkoxy.

Abstract: Novel bis type heterocyclic quaternary salts are provided which are useful in the preparation of various linked cyanine dyes and related compounds.BACKGROUND OF THE INVENTION1. Field of the InventionThis invention relates to chemistry and, more particularly, to novel double or "bis-type" quaternary salts of heterocyclic bases and processes useful in the synthesis of various linked cyanine dyes and related compounds.2. Description of the Prior ArtMost of the reactions leading to cyanine dyes and those compounds related to them are of the condensation type wherein two active dye intermediates react under suitable conditions with the elimination of some simple molecule, such as mineral acid, mercaptan, alcohol, water, aniline or acetanilide.

Abstract: Spectral sensitivity is imparted to a photosensitive material by novel linked sensitizing dye compounds having an alkylene-amide linking moiety.

Abstract: This application is directed to compounds of the formula ##EQU1## wherein R.sup.1 and R.sup.2 each represent lower alkyl and m is a whole number 2 to 5, preferably 2 or 3. These compounds are useful as silver halide solvents in photography.

Abstract: This invention relates to protonated compounds of the formula: ##SPC1##Wherein A is a radical selected from ##SPC2##X represents the atoms necessary to complete a ring-closing moiety selected from phthalide and naphthalide; and Z is an anion derived from a protic acid. These compounds are useful as intermediates in the preparation of phthalide and naphthalide indicator dyes.

Abstract: This invention relates to a process of preparing phthalein indicator dyes including phthalides and naphthalides derived from certain hydroxy-substituted carbocyclic aryl compounds, such as phenols, and from certain N-heterocyclic aryl compounds, such as indoles, and to a process of preparing novel intermediates useful therein. According to the present invention, the selected carbocyclic compound or the selected N-heterocyclic compound is reacted with phthalaldehydic or naphthalaldehydic acid to form the corresponding (na)phthalidyl adduct which is treated with an oxidizing agent to yield the subject intermediates. To prepare the indicator dye, the intermediate, i.e., the oxidation product thus obtained is then reacted with a carbocyclic or heterocyclic aryl compound to yield the corresponding indicator dye. The oxidation products comprising the novel intermediates of the present invention may be dehydro or hydrated (na)phthalidyl adducts.

Abstract: Improved green-sensitivity is imparted to a photosensitive silver halide emulsion by a benzimidazolothiacarbocyanine dye of the formula: ##SPC1##Wherein R.sup.1 and R.sup.2 are lower alkyl; R.sup.3 is sulfoalkyl or carboxyalkyl each having an alkylene chain of from 1 to 4 carbon atoms inclusive; R.sup.4 is hydrogen, halogen, lower alkyl, lower carbalkoxy, lower alkoxy or acetamido; R.sup.5 is halogen, cyano or carbalkoxy; R.sup.6 is hydrogen or halogen; Y is an anion customary in the cyanine dye art; and n is 0 or 1.

Abstract: This invention relates to a process of preparing phthalein indicator dyes including phthalides and naphthalides derived from certain hydroxy-substituted carbocyclic aryl compounds, such as phenols, and from certain N-heterocyclic aryl compounds, such as indoles, and to a process of preparing novel intermediates useful therein. According to the present invention, the selected carbocyclic compound or the selected N-heterocyclic compound is reacted with phthalaldehydic or naphthalaldehydic acid to form the corresponding (na)phthalidyl adduct which is treated with an oxidizing agent to yield the subject intermediates. To prepare the indicator dye, the intermediate, i.e., the oxidation product thus obtained is then reacted with a carbocyclic or heterocyclic aryl compound to yield the corresponding indicator dye. The oxidation products comprising the novel intermediates of the present invention may be dehydro or hydrated (na)phthalidyl adducts.

Abstract: This invention relates to a new class of phthalein dyes useful as the color-forming material in either pressure sensitive or heat sensitive mark-forming systems. Such dyes comprise 3,3-disubstituted phthalides and 3,3-disubstituted naphthalides wherein the 3,3 substituents are indolin-5-yl radicals.