US 11,926,779 B2
Liquid crystal polyester and film comprising the same
Shinji Ohtomo, Ibaraki (JP); Shohei Azami, Ibaraki (JP); Monami Tosa, Ibaraki (JP); and Nozomi Masui, Ibaraki (JP)
Assigned to SUMITOMO CHEMICAL COMPANY, LIMITED, Tokyo (JP)
Filed by SUMITOMO CHEMICAL COMPANY, LIMITED, Tokyo (JP)
Filed on Mar. 9, 2023, as Appl. No. 18/181,297.
Claims priority of application No. 2022-041387 (JP), filed on Mar. 16, 2022; and application No. 2022-122154 (JP), filed on Jul. 29, 2022.
Prior Publication US 2023/0295513 A1, Sep. 21, 2023
Int. Cl. C09K 19/38 (2006.01); C09K 19/52 (2006.01)
CPC C09K 19/3809 (2013.01) [C09K 19/52 (2013.01); C09K 2219/03 (2013.01); C09K 2219/11 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A liquid crystal polyester consisting of a repeating unit (A1) represented by the formula (A1) and a repeating unit (A2) represented by the formula (A2),
—O—Ar11—CO—  (A1)
—O—Ar12—CO—  (A2)
wherein:
a molar ratio between phenolic hydroxyl groups derived from the repeating unit (A1) and phenolic hydroxyl groups derived from the repeating unit (A2) (phenolic hydroxyl groups derived from the repeating unit (A2)/phenolic hydroxyl groups derived from the repeating unit (A1)) is 1 or lower, as calculated by 1H-NMR,
a ratio between the number of the repeating unit (A1) and the number of the repeating unit (A2) [repeating unit (A2)/repeating unit (A1)] is 1.2 or larger,
the number of the repeating unit (A1) is 20% or more based on 100% of a total number of all repeating units of the liquid crystal polyester,
the number of the repeating unit (A2) is 58% or more based on 100% of a total number of all repeating units of the liquid crystal polyester,
a flow starting temperature of the liquid crystal polyester is 250° C. or more,
Ar11 represents a phenylene group, and a hydrogen atom in the phenylene group in Ar11 is optionally substituted by a halogen atom, an alkyl group or an aryl group, and
Ar12 represents a naphthylene group, and a hydrogen atom in the naphthylene group in Ar12 is optionally substituted by a halogen atom, an alkyl group or an aryl group.