A method for manufacturing an isocyanate compound represented by formula (2) (2) wherein R1 represents a methyl group, an ethyl group, a cyclopropyl group, a chlorine atom, a bromine atom, or a methoxy group; and R2 represents an alkyl group having 1 to 6 carbon atoms, comprising reacting an aniline compound represented by formula (1) (1) wherein R1 and R2 are defined as above with a phosgene compound at a temperature of from 40° C. to the boiling point of the inert solvent in at least one kind of inert solvent.

##STR00001##

A method for manufacturing an isocyanate compound represented by formula (2) (2) wherein R1 represents a methyl group, an ethyl group, a cyclopropyl group, a chlorine atom, a bromine atom, or a methoxy group; and R2 represents an alkyl group having 1 to 6 carbon atoms, comprising reacting an aniline compound represented by formula (1) (1) wherein R1 and R2 are defined as above with a phosgene compound at a temperature of from 40° C. to the boiling point of the inert solvent in at least one kind of inert solvent.

##STR00001##

The objective of the present invention is to provide a method for producing an isocyanate compound safely and efficiently. The method for producing an isocyanate compound according to the present invention is characterized in comprising the steps of irradiating a high energy light to a halogenated methane at a temperature of 15° C. or lower in the presence of oxygen, and further adding a primary amine compound to be reacted without irradiating a high energy light.

The objective of the present invention is to provide a method for producing an isocyanate compound safely and efficiently. The method for producing an isocyanate compound according to the present invention is characterized in comprising the steps of irradiating a high energy light to a halogenated methane at a temperature of 15° C. or lower in the presence of oxygen, and further adding a primary amine compound to be reacted without irradiating a high energy light.

Disclosed is a preparation method for preparing diphenylmethane diisocyanate. The preparation method comprises: under a catalyst condition, performing a pyrolysis reaction on diphenylmethane dicarbamate in an inert solvent having a boiling point lower than that of diphenylmethane diisocyanate to obtain diphenylmethane diisocyanate.

Disclosed is a preparation method for preparing diphenylmethane diisocyanate. The preparation method comprises: under a catalyst condition, performing a pyrolysis reaction on diphenylmethane dicarbamate in an inert solvent having a boiling point lower than that of diphenylmethane diisocyanate to obtain diphenylmethane diisocyanate.

The present specification discloses a method for producing an isocyanate compound. The invention relates to a method for producing the compound represented by formula (2),

##STR00001## wherein the compound represented by formula (1)

##STR00002##

or a salt thereof is mixed with phosgene(s) under a condition such that the pH of the aqueous layer is 1 or less, in the presence of a water-immiscible solvent and water.

The present specification discloses a method for producing an isocyanate compound. The invention relates to a method for producing the compound represented by formula (2),

##STR00001## wherein the compound represented by formula (1)

##STR00002##

or a salt thereof is mixed with phosgene(s) under a condition such that the pH of the aqueous layer is 1 or less, in the presence of a water-immiscible solvent and water.

A difunctional biphenyl compounds corresponding to formula (I) ##STR00001##
wherein Alk, Alk′ and R are as defined in the description. These compounds are suitable as hardeners for thermosetting resins, especially epoxy resins.

A difunctional biphenyl compounds corresponding to formula (I) ##STR00001##
wherein Alk, Alk′ and R are as defined in the description. These compounds are suitable as hardeners for thermosetting resins, especially epoxy resins.