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US-12624001-B2 - Method for producing thiol compound

US12624001B2US 12624001 B2US12624001 B2US 12624001B2US-12624001-B2

Abstract

A method for producing a thiol compound including a light emission process in which light is emitted to a colored thiol compound or a composition containing the thiol compound. In the light emission process, it is preferable to emit light including light with a wavelength of 250 nm to 600 nm to the composition.

Inventors

  • Yuji Hashimoto

Assignees

  • SHOWA DENKO K.K.

Dates

Publication Date
20260512
Application Date
20210531
Priority Date
20200601

Claims (16)

  1. 1 . A method for producing a thiol compound, comprising a light emission process in which light is emitted to a colored thiol compound or a composition containing the colored thiol compound, wherein the colored thiol compound has a Hazen color number of 10 or more, and the thiol compound includes one or both of 3-mercaptocarboxylic acid and 3-mercaptocarboxylic acid ester.
  2. 2 . The method for producing a thiol compound according to claim 1 , wherein the light includes light with a wavelength of 250 nm to 600 nm.
  3. 3 . The method for producing a thiol compound according to claim 1 , wherein the Hazen color number of the thiol compound or the composition is 100 or more, and wherein the light emission process is performed until the Hazen color number of the thiol compound or the composition is less than 100.
  4. 4 . The method for producing a thiol compound according to claim 1 , wherein the thiol compound includes a thiol having at least one secondary mercapto group.
  5. 5 . The method for producing a thiol compound according to claim 1 , wherein the thiol compound includes one or both of 3-mercaptobutanoic acid and 3-mercaptobutanoic acid ester.
  6. 6 . The method for producing a thiol compound according to claim 5 , wherein the 3-mercaptobutanoic acid ester is any one of compounds represented by the following Formulae (3) and (4): (in Formula (3), R 4 and R 5 each independently represent a hydrogen atom or a group represented by Formula (5)) (in Formula (4), R 6 , R 7 , and R 8 each independently represent a hydrogen atom or a group represented by Formula (5)) (in Formula (5), * indicates bonding positions for compounds represented by Formulae (3) and (4)).
  7. 7 . The method for producing a thiol compound according to claim 5 , wherein the 3-mercaptobutanoic acid ester is a compound represented by the following Formula (9):
  8. 8 . The method for producing a thiol compound according to claim 1 , wherein the composition contains the thiol compound and at least one solvent selected from the group consisting of toluene, xylene, cyclohexane, methylcyclohexane, acetonitrile, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and water.
  9. 9 . The method for producing a thiol compound according to claim 2 , wherein the Hazen color number of the thiol compound or the composition is 100 or more, and wherein the light emission process is performed until the Hazen color number of the thiol compound or the composition is less than 100.
  10. 10 . The method for producing a thiol compound according to claim 2 , wherein the thiol compound includes a thiol having at least one secondary mercapto group.
  11. 11 . The method for producing a thiol compound according to claim 3 , wherein the thiol compound includes a thiol having at least one secondary mercapto group.
  12. 12 . The method for producing a thiol compound according to claim 9 , wherein the thiol compound includes a thiol having at least one secondary mercapto group.
  13. 13 . The method for producing a thiol compound according to claim 2 , wherein the composition contains the thiol compound and at least one solvent selected from the group consisting of toluene, xylene, cyclohexane, methylcyclohexane, acetonitrile, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and water.
  14. 14 . The method for producing a thiol compound according to claim 3 , wherein the composition contains the thiol compound and at least one solvent selected from the group consisting of toluene, xylene, cyclohexane, methylcyclohexane, acetonitrile, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and water.
  15. 15 . The method for producing a thiol compound according to claim 4 , wherein the composition contains the thiol compound and at least one solvent selected from the group consisting of toluene, xylene, cyclohexane, methylcyclohexane, acetonitrile, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and water.
  16. 16 . The method for producing a thiol compound according to claim 7 , wherein the composition contains the thiol compound and at least one solvent selected from the group consisting of toluene, xylene, cyclohexane, methylcyclohexane, acetonitrile, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and water.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a National Stage of International Application No. PCT/JP2021/020600 filed May 31, 2021, claiming priority based on Japanese Patent Application No. 2020-095577 filed Jun. 1, 2020, the content of which is incorporated herein by reference. TECHNICAL FIELD The present invention relates to a method for producing a thiol compound. BACKGROUND ART In recent years, in order to save energy and improve productivity, there has been a demand for a curable resin with favorable curability that cures quickly with little energy. As such a curable resin, a curable resin containing thiols is being focused on. For example, Patent Document 1 and Patent Document 2 describe photocurable resin compositions containing a thiol compound. Patent Document 3 describes that a resin composition containing a thiol compound is photocured and then thermally cured. Patent Document 4 to Patent Document 7 describe resin compositions containing a thiol compound and having excellent low-temperature curability. In addition, Patent Document 8 describes a production method for producing a mercaptocarboxylic acid polyhydric alcohol ester according to an esterification reaction of mercaptocarboxylic acid or mercaptocarboxylic acid ester and a polyhydric alcohol. Patent Document 8 describes that the produced tetrakis(3-mercaptobutanoic acid) pentaerythritol ester is a light yellow liquid. CITATION LIST Patent Document [Patent Document 1] Japanese Patent No. 5801556 [Patent Document 2] Japanese Patent No. 6468315 [Patent Document 3] Japanese Patent No. 6184003 [Patent Document 4] Japanese Unexamined Patent Application, First Publication No. 2015-93887 [Patent Document 5] Japanese Unexamined Patent Application, First Publication No. 2017-43721 [Patent Document 6] Japanese Unexamined Patent Application, First Publication No. 2016-12131 [Patent Document 7] Japanese Unexamined Patent Application, First Publication No. 2016-104875 [Patent Document 8] Japanese Unexamined Patent Application, First Publication No. 2011-084479 [Patent Document 9] Japanese Patent No. 5713886 SUMMARY OF INVENTION Technical Problem In the related art, curable resins used for specific applications have been required to have little coloring and excellent transparency. Specific applications are, for example, optical materials, and the outer surfaces of final products. In recent years, it has been required to improve curability of curable resins used for such specific applications. However, thiol compounds are typically colored yellow, orange, brown, red or the like in some cases. It is difficult for a curable resin that requires transparency to contain a colored thiol compound in order to improve curability. Therefore, there is a need for a technique for reducing coloring of thiol compounds. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for producing a thiol compound by which it is possible to reduce coloring of the thiol compound. Solution to Problem [1] A method for producing a thiol compound, including a light emission process in which light is emitted to a colored thiol compound or a composition containing the thiol compound.[2] The method for producing a thiol compound according to [1], wherein the light includes light with a wavelength of 250 nm to 600 nm.[3] The method for producing a thiol compound according to [1] or [2], wherein the Hazen color number of the thiol compound or the composition is 100 or more, andwherein the light emission process is performed until the Hazen color number of the thiol compound or the composition is less than 100. [4] The method for producing a thiol compound according to any one of [1] to [3], wherein the thiol compound includes a thiol having at least one secondary mercapto group. [5] The method for producing a thiol compound according to any one of [1] to [3], wherein the thiol compound includes one or both of 3-mercaptocarboxylic acid and 3-mercaptocarboxylic acid ester. [6] The method for producing a thiol compound according to [5], wherein the thiol compound includes one or both of 3-mercaptobutanoic acid and 3-mercaptobutanoic acid ester. [7] The method for producing a thiol compound according to [6], wherein the 3-mercaptobutanoic acid ester is any one of compounds represented by the following Formulae (1) to (4): (in Formula (1), R1 represents a hydrogen atom or a group represented by Formula (5)) (in Formula (2), R2 and R3 each independently represent a hydrogen atom or a group represented by Formula (5))(in Formula (3), R4 and R5 each independently represent a hydrogen atom or a group represented by Formula (5))(in Formula (4), R6, R7, and R8 each independently represent a hydrogen atom or a group represented by Formula (5))(in Formula (5), * indicates bonding positions for compounds represented by Formulae (1