Abstract: A photopolymerization sensitizer may not cause problems of dusting or coloring of a cured product due to bleeding of additives such as the photopolymerization sensitizer on the surface, e.g., by blooming at the time of photo-curing or during storage of the cured product, and which provides a practically sufficient photo-curing rate. A 9,10-bis(alkoxycarbonylalkyleneoxy)anthracene compound having ester groups, of formula (I): wherein A is a C1-20 alkylene group, optionally branched by an alkyl group, R is a C1-20 alkyl group, optionally branched by the alkyl group, the C1-20 alkyl group optionally being a cycloalkyl group or a cycloalkylalkyl group, and X and Y are independently a hydrogen, a C1-8 alkyl group, or a halogen.

Abstract: To provide a photopolymerization sensitizer which will not cause problems of dusting or coloring of a cured product by bleeding of additives such as the photopolymerization sensitizer on the surface e.g. by blooming at the time of photo-curing or during storage of the cured product, and which imparts a practically sufficient photo-curing rate. An oligomer of a 9,10-bis(substituted oxy)anthracene compound having repeating units represented by the following formula (1): wherein n represents a repetition number and is from 2 to 50, each of X and Y which may be the same or different, is a hydrogen atom, a C1-8 alkyl group or a halogen atom, and A is a bivalent substituent.

Abstract: A photopolymerization sensitizer may not cause problems of dusting or coloring of a cured product due to bleeding of additives such as the photopolymerization sensitizer on the surface, e.g., by blooming at the time of photo-curing or during storage of the cured product, and which provides a practically sufficient photo-curing rate. A 9,10-bis(alkoxycarbonylalkyleneoxy)anthracene compound having ester groups, of formula (I): wherein A is a C1-20 alkylene group, optionally branched by an alkyl group, R is a C1-20 alkyl group, optionally branched by the alkyl group, the C1-20 alkyl group optionally being a cycloalkyl group or a cycloalkylalkyl group, and X and Y are independently a hydrogen, a C1-8 alkyl group, or a halogen.

Abstract: To provide a photopolymerizable composition which can be quickly cured by light of from 300 nm to 450 nm, and a cured product of which is less colored. A photopolymerization sensitizer composition containing a compound represented by the following formula (1) and a compound, of which the maximum value of an absorption coefficient in a wavelength region ranging from at least 400 nm to at most 500 nm is higher than the maximum value of an absorption coefficient in a wavelength region ranging from at least 400 nm to at most 500 nm of said compound; and a photopolymerizable composition containing the photopolymerization sensitizer composition.

Abstract: To provide a photopolymerization sensitizer which will not cause problems of dusting or coloring of a cured product by bleeding of additives such as the photopolymerization sensitizer on the surface e.g. by blooming at the time of photo-curing or during storage of the cured product, and which imparts a practically sufficient photo-curing rate. An oligomer of a 9,10-bis(substituted oxy)anthracene compound having repeating units represented by the following formula (1): wherein n represents a repetition number and is from 2 to 50, each of X and Y which may be the same or different, is a hydrogen atom, a C1-8 alkyl group or a halogen atom, and A is a bivalent substituent.

Abstract: To provide a photopolymerizable composition which can be quickly cured by light of from 300 nm to 500 nm, and a cured product of which is less colored. A photopolymerizable composition comprising a compound having an anthracene skeleton represented by the following formula (1), a compound having a benzophenone skeleton and a radical polymerizable compound: wherein each of R1 and R2 which may be the same or different, is a C1-20 alkyl group, a C6-20 aryl group, an alkylcarbonyl group having a C1-20 alkyl group, an arylcarbonyl group having a C6-20 aryl group, an alkyloxycarbonyl group having a C1-20 alkyl group, or an aryloxycarbonyl group having a C6-20 aryl group, and each of X and Y which may be the same or different, is a hydrogen atom or a C1-8 alkyl group.

Abstract: To provide a photopolymerizable composition which can be quickly cured by light of from 300 nm to 450 nm, and a cured product of which is less colored. A photopolymerization sensitizer composition containing a compound represented by the following formula (1) and a compound, of which the maximum value of an absorption coefficient in a wavelength region ranging from at least 400 nm to at most 500 nm is higher than the maximum value of an absorption coefficient in a wavelength region ranging from at least 400 nm to at most 500 nm of said compound; and a photopolymerizable composition containing the photopolymerization sensitizer composition.

Abstract: To provide a photopolymerizable composition which can be quickly cured by light of from 300 nm to 500 nm, and a cured product of which is less colored. A photopolymerizable composition comprising a compound having an anthracene skeleton represented by the following formula (1), a compound having a benzophenone skeleton and a radical polymerizable compound: wherein each of R1 and R2 which may be the same or different, is a C1-20 alkyl group, a C6-20 aryl group, an alkylcarbonyl group having a C1-20 alkyl group, an arylcarbonyl group having a C6-20 aryl group, an alkyloxycarbonyl group having a C1-20 alkyl group, or an aryloxycarbonyl group having a C6-20 aryl group, and each of X and Y which may be the same or different, is a hydrogen atom or a C1-8 alkyl group.

Abstract: An industrially advantageous process is presented whereby a high purity anthracene diether can be produced in good yield. An aqueous medium containing an alkali salt of 9,10-anthracenediol is added to an organic solvent containing an etherifying agent in the presence or absence of a quaternary ammonium compound or a quaternary phosphonium compound, to carry out the etherifying reaction to produce the anthracene diether.

Abstract: An industrially advantageous process is presented whereby a high purity anthracene diether can be produced in good yield. An aqueous medium containing an alkali salt of 9,10-anthracenediol is added to an organic solvent containing an etherifying agent in the presence or absence of a quaternary ammonium compound or a quaternary phosphonium compound, to carry out the etherifying reaction to produce the anthracene diether.

Abstract: A method for the treatment of waste water, which comprises treating waste water containing at least a sulfide-type malodorous substance, in the presence of a transition metal compound and hydrogen peroxide or a hydrogen peroxide-forming compound, wherein at least an iron family element compound and a vanadium family element compound are used as the transition metal compound.

Abstract: A process for oxidizing an organic compound by ceric sulfate dissolved in an aqueous sulfuric acid solution, wherein the organic compound is oxidized (1) by means of a ceric sulfate-aqueous sulfuric acid solution or a cerous sulfate-containing ceric sulfate-aqueous sulfuric acid solution in which the molar concentration (mol/liter) of ceric sulfate is at least the molar concentration of cerium (ions) contained in the molecules of cerous sulfate at the maximum solubility of cerous sulfate in an aqueous sulfuric acid solution at the final sulfuric acid concentration (exclusive of ceric sulfate and cerous sulfate) and at the temperature under the oxidation reaction conditions and at most the saturated molar concentration of ceric sulfate in said aqueous sulfuric acid solution, (2) under a condition such that at the end of the oxidation reaction, the concentration of ceric sulfate is maintained at a level capable of dissolving cerous sulfate which is present at a concentration of at least the maximum solubility o

Abstract: A process for preparing a quinone, which comprises reacting a polynuclear aromatic hydrocarbon and a ceric salt in an aqueous acid solution in the presence of an organic solvent selected from the group consisting of chlorobenzene and an alkylbenzene represented by the general formula: ##STR1## where each of R.sub.1, R.sub.2 and R.sub.3 is an alkyl group and the total carbon number of the alkyl groups is from 3 to 6.

Abstract: A method for electrolyzing cerous sulfate in the electrolytic oxidation of cerous sulfate to ceric sulfate in an aqueous sulfuric acid solution, characterized in that the concentration of the cerous sulfate in the electrolyte to be supplied to the electrolytic cell is maintained, by the presence of ceric sulfate, at a level of at least the saturated concentration of cerous sulfate in the aqueous sulfuric acid solution (exclusive of the cerous sulfate and ceric sulfate) at the initial sulfuric acid concentration and at the temperature of electrolysis, and at most the saturated concentration of cerous sulfate in the presence of the ceric sulfate in the aqueous sulfuric acid solution at the initial sulfuric acid concentration and at the temperature of electrolysis, and the concentration of the ceric sulfate in the electrolyte is maintained at a level of at most the saturated concentration of ceric sulfate in the aqueous sulfuric acid solution at the initial sulfuric acid concentration and at the temperature of e

Abstract: In a process for purifying crude anthraquinone obtained by the oxidation, by molecular oxygen in an aqueous alkali metal hydroxide solution, of an adduct obtained by the Diels-Alder reaction of butadiene with 1,4-naphthoquinone obtained by a catalytic vapor phase oxidation reaction of naphthalene, an improvement characterized in that said crude anthraquinone is subjected to oxidation treatment in an aqueous medium in the presence of a hypochlorite.

Abstract: A hydroanthraquinone is produced from a reaction mixture obtained by the Diels-Alder reaction of naphthoquinone with a conjugated diolefin in an inert organic solvent. The reaction mixture in an inert organic solvent is oxidized with an oxidizing agent to decompose quinhydrone or quinhydrone derivative produced by said Diels-Alder reaction and the crystallized hydroanthraquinones are separated from said inert organic solvent.

Abstract: Electric blower assembly wherein air expelled by centrifugal force from impellers passes through volute chambers disposed peripherally with respect to said impellers and each defining a space which is increasingly larger as the distance from the impellers increases, whereby smooth air flow is produced in the volute chambers since the speed of air flow therethrough is lessened and pressure therein becomes static pressure. From the volute chambers air passes along inclined channels and then around a drive motor, whereby the drive motor is cooled. In entering at least part of each volute chamber air from the impellers comes into contact with a volute chamber wall extension which becomes gradually lower in a direction opposing that of impeller rotation whereby noise due to contact of a volute chamber wall by all portions of the air from the impeller does not occur simultaneously and a quieter blower assembly is provided.