A lacquer composition is provided, comprising 20%-79.9% by weight, based on the total weight of the composition, of a thiol compound having two or more thiol groups, 20%-79.9% by weight, based on the total weight of the composition, of a compound having two or more carbon-carbon double bonds and 0.1%-10% by weight, based on the total weight of the composition, of a separating agent having an alkyl radical having 4-20 carbon atoms, where the alkyl radical is unsubstituted or fluorine-substituted and the alkyl radical is bonded to a functional group. Also provided are the use of this lacquer composition as a protective lacquer on an optical surface of an optical element in the production of the optical element, and an optical element comprising the protective lacquer.

Aspects of the present disclosure relate to Schiff base oligomers and uses thereof. In at least one aspect, an oligomer is represented by Formula (IV) wherein each instance of R.sup.9 is independently selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, and ether. Each instance of R.sup.28 and R.sup.29 of Formula (IV) is independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, and aryl. Each instance of R.sup.33 of Formula (IV) is independently selected from the group consisting of alkyl, cycloalkyl, aryl, heterocyclyl, and a bond. Each instance of R.sup.41 of Formula (IV) is independently —NH— or a bond and each instance of R.sup.40 is independently —NH— or —NH—NH—. Each instance of R.sup.42 of Formula (IV) is independently —NH— or a bond and each instance of R.sup.43 is independently —NH— or —NH—NH—.

An iso(thio)cyanate compound that is a reaction product between an amine compound (A) including at least one selected from a compound (a1) represented by general formula (1) or a compound (a2) represented by general formula (2) and a bi- or higher-functional iso(thio)cyanate compound (B), the iso(thio)cyanate compound having a value of Mw/Mn of 1.31 or less, the value of Mw/Mn being a weight average molecular weight (Mw) divided by a number average molecular weight (Mn).

Aspects of the present disclosure relate to Schiff base oligomers and uses thereof. In at least one aspect, an oligomer is represented by Formula (IV) wherein each instance of R.sup.9 is independently selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, and ether. Each instance of R.sup.28 and R.sup.29 of Formula (IV) is independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, and aryl. Each instance of R.sup.33 of Formula (IV) is independently selected from the group consisting of alkyl, cycloalkyl, aryl, heterocyclyl, and a bond. Each instance of R.sup.41 of Formula (IV) is independently —NH— or a bond and each instance of R.sup.40 is independently —NH— or —NH—NH—. Each instance of R.sup.42 of Formula (IV) is independently —NH— or a bond and each instance of R.sup.43 is independently —NH— or —NH—NH—.

A method for producing an organic mercapto compound or an intermediate thereof according to the present invention has a reaction step of reacting an alcohol compound including a sulfur atom with a thioamide compound having a structure in which an organic group is bonded to at least one bonding hand of a thioamide group, under acidic conditions.

A method for producing a polythiol compound includes reacting a polyol compound with thiourea in which a content of ammonium thiocyanate is 0.05% by mass or less to obtain an isothiuronium salt.

Aspects of the present disclosure relate to Schiff base oligomers and uses thereof In at least one aspect, an oligomer is represented by Formula (IV) wherein each instance of R.sup.9 is independently selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, and ether. Each instance of R.sup.28 and R.sup.29 of Formula (IV) is independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, and aryl. Each instance of R.sup.33 of Formula (IV) is independently selected from the group consisting of alkyl, cycloalkyl, aryl, heterocyclyl, and a bond. Each instance of R.sup.41 of Formula (IV) is independently NH or a bond and each instance of R.sup.40 is independently NH or NHNH. Each instance of R.sup.42 of Formula (IV) is independently NH or a bond and each instance of R.sup.43 is independently NH or NHNH.

A method for producing an organic mercapto compound or an intermediate thereof according to the present invention has a reaction step of reacting an alcohol compound including a sulfur atom with a thioamide compound having a structure in which an organic group is bonded to at least one bonding hand of a thioamide group, under acidic conditions.

A lacquer composition is provided, comprising 20%-79.9% by weight, based on the total weight of the composition, of a thiol compound having two or more thiol groups, 20%-79.9% by weight, based on the total weight of the composition, of a compound having two or more carbon-carbon double bonds and 0.1%-10% by weight, based on the total weight of the composition, of a separating agent having an alkyl radical having 4-20 carbon atoms, where the alkyl radical is unsubstituted or fluorine-substituted and the alkyl radical is bonded to a functional group. Also provided are the use of this lacquer composition as a protective lacquer on an optical surface of an optical element in the production of the optical element, and an optical element comprising the protective lacquer.

Crosslinked polydithiocarbamates based on 1,3,5-triazinane cores linked to pyrrole-dithiocarbamates via alkyl chains. A process for preparing these crosslinked polydithiocarbamates via a Mannich-type polycondensation of diaminoalkane, paraformaldehyde and a pyrrole compound, which is followed by additional modification of the pyrrole moiety to a pyrrole-dithiocarbamate. A method for removing heavy metals, such as Cd(II) from an aqueous solution or an industrial wastewater sample with these crosslinked polydithiocarbamates is also described.