Claims
- 1. A wholly aromatic polyester which exhibits optical anisotropy in a molten state and which comprises, as essential constituents, the constitutional unit (I) in an amount of 40 to 75 mol %, the constitutional unit (II) in an amount of 8.5 to 30 mol %, the constitutional unit (III) in an amount of 8.5 to 30 mol % and the constitutional unit (IV) in an amount of 0.1 to 8 mol % based on the total of all constitutional units, the constitutional units (I) to (IV) being represented by the following formulas: wherein Ar1 is 2,6-naphthalene; Ar2 is at least one selected from the group consisting of 1,2-phenylene, 1,3-phenylene and 1,4-phenylene; Ar3 is at least one selected from the group consisting of 1,3-phenylene, 1,4-phenylene and the residue of a compound having at least two phenylene groups connected with each other at the para position; and Ar4 is 1,4-phenylene.
- 2. The polyester of claim 1, which contains the constitutional unit (I) in an amount of 40 to 60 mol %, the constitutional unit (II) in an amount of 17.5 to 30 mol %, the constitutional unit (III) in an amount of 17.5 to 30 mol % and the constitutional unit (IV) in an amount of 1 to 6 mol % based on the total of all constitutional units.
- 3. The polyester of claim 1, wherein the ratio (I)/(IV) of the constitutional unit (I) to the constitutional unit (IV) is 6 to 150.
- 4. The polyester of claim 1, which has a melt viscosity of not higher than 1×105 Pa·s at temperatures higher than its melting point by 10 to 40° C. and a shear rate of 1,000 sec−1.
- 5. The polyester of claim 1, which has a melting point of 340 to 380° C. and a difference between its melting point and its softening temperature of not higher than 50° C.
- 6. A polyester resin composition comprising a wholly aromatic polyester of claim 1, and an inorganic or organic filler in an amount of between 100 parts by weight to 120 parts by weight of the wholly aromatic polyester.
- 7. A polyester article molded from the wholly aromatic polyester of claim 1.
- 8. The article of claim 7, which is a relay switch part, a bobbin, an actuator, a noise reduction filter case or a hot fixing roller for OA equipment.
- 9. A polyester article molded from the polyester resin composition of claim 6.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2000-288413 |
Sep 2000 |
JP |
|
Parent Case Info
This application is the US national phase of international application PCT/JP01/08056 filed 17 Sep. 2001 which designated the U.S.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/JP01/08056 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO02/24783 |
3/28/2002 |
WO |
A |
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4219461 |
Calundann |
Aug 1980 |
A |
4256624 |
Calundann |
Mar 1981 |
A |
Foreign Referenced Citations (5)
Number |
Date |
Country |
426481 |
May 1991 |
EP |
462481 |
May 1991 |
EP |
56-10526 |
Feb 1981 |
JP |
5117374 |
May 1993 |
JP |
8143653 |
Jun 1996 |
JP |