Treatment agent for carbon fiber precursor, aqueous solution of treatment agent for carbon fiber precursor, carbon fiber precursor, and method for producing carbon fibers

Patent metadata

Field	Value
Publication number	US-11879205-B2
Application number	US-202117905118-A
Country	US
Kind code	B2
Filing date	Jun 2, 2021
Priority date	Jun 9, 2020
Publication date	Jan 23, 2024
Grant date	Jan 23, 2024

Abstract

The present invention addresses the problem of suitably improving a treatment agent for a carbon fiber precursor in terms of the heat resistance and the effect of suppressing fusion between fibers during the step of flame-resisting treatment. This treatment agent for a carbon fiber precursor is characterized by containing a lubricant, the lubricant comprising a specific sulfur-containing diester compound and a specific sulfur-containing monoester compound.

First claim

The invention claimed is:

1. A carbon fiber precursor treatment agent comprising
a lubricant, wherein the lubricant contains a modified silicone having a modified group that includes a nitrogen atom, a sulfur-containing diester compound represented by Formula I shown below:
R 1 —OOC—(CH 2 ) a —S—(CH 2 ) b —COO—R 2   [1]

wherein a and b are each an integer from 1 to 10, and R 1 and R 2 are each a residue obtained by removing a hydroxy group from a saturated alcohol with 17 to 32 carbon atoms or a residue obtained by removing a hydroxy group from an alkylene oxide adduct of a saturated alcohol with 17 to 32 carbon atoms, and
a sulfur-containing monoester compound represented by Formula 2 Formula II shown below:
R 1 —OOC—(CH 2 ) a —S—(CH 2 ) b —COO—R 2   [2]

wherein c and d are each an integer from 1 to 10, and R 3 is a residue obtained by removing a hydroxy group from a saturated alcohol with 17 to 32 carbon atoms or a residue obtained by removing a hydroxy group from an alkylene oxide adduct of a saturated alcohol with 17 to 32 carbon atoms.

2. The carbon fiber precursor treatment agent according to claim 1 , wherein a mass ratio of a content of the sulfur-containing diester compound of Formula I and a content of the sulfur-containing monoester compound of Formula II is 99.999/0.001 to 80/20.

3. The carbon fiber precursor treatment agent according to claim 1 , wherein at least one selected from among R 1 in the Formula I, the R 2 in the Formula I, and the R 3 in the Formula II is a residue obtained by removing a hydroxy group from a saturated alcohol with 17 to 32 carbon atoms having a branched chain or a residue obtained by removing a hydroxy group from an alkylene oxide adduct of a saturated alcohol with 17 to 32 carbon atoms having a branched chain.

4. The carbon fiber precursor treatment agent according to claim 1 , wherein at least one selected from among R 1 in the Formula I, R 2 in the Formula I, and R 3 in the Formula 2Formula II is a residue obtained by removing a hydroxy group from a saturated Guerbet alcohol with 17 to 32 carbon atoms or a residue obtained by removing a hydroxy group from an alkylene oxide adduct of a saturated Guerbet alcohol with 17 to 32 carbon atoms.

5. The carbon fiber precursor treatment agent according to claim 1 , wherein at least one selected from among R 1 in the Formula I, R 2 in the Formula I, and R 3 in the Formula II has 24 to 32 carbon atoms.

6. The carbon fiber precursor treatment agent according to claim 1 , wherein
if a total content of the sulfur-containing diester compound, the sulfur-containing monoester compound, and the modified silicone is taken as 100% by mass, the sulfur-containing diester compound and the sulfur-containing monoester compound are contained at a ratio of 30% to 95% by mass in total.

7. The carbon fiber precursor treatment agent according to claim 1 , further containing a surfactant.

8. The carbon fiber precursor treatment agent according to claim 1 , further containing a surfactant, and wherein
the lubricant further contains a modified silicone having a modified group that includes a nitrogen atom, and
if a total content of the sulfur-containing diester compound, the sulfur-containing monoester compound, the modified silicone, and the surfactant is taken as 100% by mass, the sulfur-containing diester compound and the sulfur-containing monoester compound are contained at a ratio of 20% to 75% by mass in total.

9. An aqueous liquid of a carbon fiber precursor treatment agent, comprising the carbon fiber precursor treatment agent according to claim 1 and water.

10. A carbon fiber precursor to which the carbon fiber precursor treatment agent according to claim 1 is adhered.

11. A method for producing a carbon fiber, comprising adhering the carbon fiber precursor treatment agent according to claim 1 to a carbon fiber precursor.

12. A method for producing a carbon fiber, comprising making a yarn by adhering the carbon fiber precursor treatment agent according to claim 1 to a carbon fiber precursor;
converting the carbon fiber precursor to a flame-resistant fiber in an oxidizing atmosphere of 200° C. to 300° C.; and
carbonizing the flame-resistant fiber in an inert atmosphere of 300° C. to 2,000° C.

Assignees

• Takemoto Oil & Fat Co Ltd

Inventors

• Oda Kohei
• Honda Hiroki

Classifications

• D06M13/252 Primary

  Mercaptans, thiophenols, sulfides or polysulfides, e.g. mercapto acetic acid; Sulfonium compounds · CPC title

• D01F9/21

  from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• D06M15/6436

  containing amino groups · CPC title

• D06M2101/26

  Polymers or copolymers of unsaturated carboxylic acids or derivatives thereof · CPC title

• D06M2200/40

  Reduced friction resistance, lubricant properties; Sizing compositions · CPC title