Process for tinting a resin having a large refractivity index and optical material tinted by the process

A process for tinting a resin comprising dipping a resin into a liquid containing at least one polar compound selected from the group consisting of polar inorganic compounds and polar organic compounds and subsequently tinting the resin, wherein the resin is obtained by curing by polymerization of a sulfur-containing compound alone or a composition comprising the sulfur-containing compound, the sulfur-containing compound having in the molecule thereof one or more structures represented by the following formula (2):

• wherein R1 represents a hydrocarbon group having 1 to 10 carbon atoms, R2, R3 and R4 each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms and Y represents S or O.

A process for tinting a resin comprising dipping a resin into a liquid containing at least one polar compound selected from the group consisting of polar inorganic compounds and polar organic compounds and subsequently tinting the resin, wherein the resin is obtained by curing by polymerization of a sulfur-containing compound alone or a composition comprising the sulfur-containing compound, the sulfur-containing compound having in the molecule thereof one or more structures represented by the following formula (3):

• wherein R1 represents a hydrocarbon group having 1 to 10 carbon atoms and R2, R3 and R4 each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms.

A process for tinting a resin comprising dipping a resin into a liquid containing at least one polar compound selected from the group consisting of polar inorganic compounds and polar organic compounds and subsequently tinting the resin, wherein the resin is obtained by curing by polymerization of a sulfur-containing compound alone or a composition comprising the sulfur-containing compound, the compound being represented by the following formula (4):

• wherein R5 to R10 each represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, X represents S or O, an average number of S represented by X is 50% or more of a total number of S and O constituting the three-membered rings, m represents 1 to 6 and n represents 0 to 4.