Claims
- 1. A fluorine-containing polyhydroxyamide represented by the general formula (2): where X is a tetravalent organic group containing an aromatic ring, and two sets of N and O are each bonded to the ortho positions of said aromatic ring of X such that two five-membered rings are formed next to said aromatic ring of X.
- 2. A polyhydroxyamide according to claim 1, which has a reduced viscosity of 0.01 dl/g or more, when a solution is prepared by dissolving said polyhydroxyamide in dimethyl acetamide to have a concentration of 0.1 g/dl and when viscosity of said solution is measured with an Ostwald viscosimeter at 30° C.
- 3. A method for producing a fluorine-containing polybenzoxazole comprising a structural unit represented by the general formula (1): said method comprising cyclizing a fluorine-containing polyhydroxyamide represented by the general formula (2): where, in each of the general formulas (1) and (2), X is a tetravalent organic group containing an aromatic ring, and two sets of N and O are each bonded to the ortho positions of said aromatic ring of X such that two five-membered rings are formed next to said aromatic ring of X.
- 4. A method according to claim 3, wherein said polyhydroxyamide is prepared by reacting a dicarboxylic acid with a bis(aminophenol) compound represented by the general formula (3): where each of R1, R2, R3 and R4 is independently hydrogen atom or trialkylsilyl group, and X is the same as that defined in the general formula (1), andwherein said dicarboxylic acid comprises an acid component that is at least one of 2,2′-bis(trifluoromethyl)-4,4′-biphenyldicarboxylic acid, which is represented by the formula (4), and an amide-forming derivative of said 2,2′-bis(trifluoromethyl)-4,4′-biphenyldicarboxylic acid.
- 5. A method according to claim 4, wherein said amide forming derivative is an acid halide of said 2,2′-bis(trifluoromethyl)-4,4′-biphenyldicarboxylic acid or a dialkylester of said 2,2′-bis(trifluoromethyl)-4,4′-biphenyldicarboxylic acid.
- 6. A method according to claim 4, wherein said dicarboxylic acid comprises 5-100% of said acid component.
- 7. A method according to claim 4, wherein X is an organic group represented by one of the general formulas (5) and (6): where, in each of the general formulas (5) and (6), unfixed bond lines are located at the ortho position on each benzene ring, and a hydrogen atom of each aromatic ring is optionally replaced with a halogen selected from the group consisting of fluorine, chlorine, bromine and iodine.
- 8. A method according to claim 3, wherein said cyclizing is conducted at a temperature of not lower than 100° C.
- 9. A method according to claim 4, wherein said reacting is conducted between substantially equimolar amounts of said dicarboxylic acid and said bis(aminophenol) compound.
Priority Claims (1)
Number |
Date |
Country |
Kind |
11-102482 |
Apr 1999 |
JP |
|
Parent Case Info
This application is a division of application Ser. No. 09/544,502, filed Apr. 7, 2000 now U.S. Pat. No. 6,291,635.
US Referenced Citations (7)
Foreign Referenced Citations (3)
Number |
Date |
Country |
42-19271 |
Sep 1942 |
JP |
62-207332 |
Sep 1987 |
JP |
3-290434 |
Dec 1991 |
JP |
Non-Patent Literature Citations (1)
Entry |
Maruyama et al., “Macromolecules”, American Chemical Society, vol. 21, No. 8, Aug. 1988, pp. 2305-2309. |