Liquid crystalline polyester resin composition for a connector

• US 6,680,002 B2
• Filed: 02/04/2003
• Issued: 01/20/2004
• Est. Priority Date: 02/25/2002
• Status: Active Grant

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Sumitomo Chemical Company Limited
• Inventors: Nagano, Satoshi, Okamoto, Satoshi, Yamauchi, Hiroyasu
• Primary Examiner(s): Huff, Mark F.
• Assistant Examiner(s): Sadula, Jennifer R.
• Application Number:
  US10/357,334
• Publication Number:
  US 20030168634A1
• Time in Patent Office: 350 Days
• Field of Search: 252/299.01, 252/299.6, 252/299.61, 252/299.62, 252/299.63, 252/299.64, 252/299.68, 428/1.2, 523/1, 523/500, 523/522, 523/526, 525/7, 525/7.1, 525/11, 525/25, 525/26
• US Class Current: 252/299.01
• CPC Class Codes: C08K 3/013 Fillers, pigments or reinforcing additives
• CPC Class Codes: C08L 2666/18 Polyesters or polycarbonates according to C08L67/00 - C08L69/00; Derivatives thereof
• CPC Class Codes: C08L 67/00 Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain of polyester-amides C08L77/12; of polyester-imides C08L79/08; Compositions of derivatives of such polymers
• CPC Class Codes: H01R 13/46 Bases; Cases

Abstract

The object of the present invention is to provide a liquid crystalline polyester resin composition for connectors that is excellent in fluidity at the time of molding and is therefore capable of producing connectors with further suppressed degree of warpage. The object is achieved by providing a liquid crystalline polyester resin composition for connectors comprising a liquid crystalline polyester resin mixture which comprises a liquid crystalline polyester (A) having a specific flow beginning temperature and a liquid crystalline polyester resin (B) having a specific flow beginning temperature and the flow beginning temperature between the liquid crystalline polyester resin (A) and the liquid crystalline polyester resin (B) is from 20° C. to 60° C., and from 15 to 180 parts by weight of a fibrous and/or plate-shaped inorganic filler; wherein both of the liquid crystalline polyester resin (A) and the liquid crystalline polyester resin (B) are produced by the specific method.

Claims

1. A liquid crystalline polyester resin composition for connector comprising 100 parts by weight of a liquid crystalline polyester resin mixture which comprises 100 parts by weight of a liquid crystalline polyester (A) having a flow beginning temperature of from 300°

C. to 400°

C. and from 10 to 150 parts by weight of a liquid crystalline polyester resin (B) having a flow beginning temperature of 260°

C. to 350°

C. and the difference between the flow beginning temperature of the liquid crystalline polyester resin (A) and the flow beginning temperature of the liquid crystalline polyester resin (B) is from 20°

C. to 60°

C., and from 15 to 180 parts by weight of a fibrous and/or plate-shaped inorganic filler;

wherein both of the liquid crystalline polyester resin (A) and the liquid crystalline polyester resin (B) are produced by ester exchange reaction between at least one selected from a group consisting of aromatic dicarboxylic acids and aromatic hydroxycarboxylic acids, and an acylated compound obtained by acylation of phenolic hydroxyl group of at least one selected from a group consisting of aromatic diols and aromatic hydroxycarboxylic acids with a fatty acid anhydride, and at least one of the acylation and the ester exchange reaction is carried out in the presence of a heterocyclic organic basic compound having two or more nitrogen atoms.

2. The liquid crystalline polyester resin composition according to claim 1, wherein the heterocyclic organic basic compound having two or more nitrogen atoms is imidazole compound represented by the formula (1),

wherein, R₁ to R₄ independently represent hydrogen atom, an alkyl with 1 to 4 carbons, hydroxymethyl, cyano, a cyanoalkyl with 2 to 5 carbons, a cyanoalkoxyl with 2 to 5 carbons, carboxyl, amino, an aminoalkyl with 1 to 4 carbons, an aminoalkoxy with 1 to 4 carbons, phenyl, benzyl, phenyipropyl or formyl.

3. The liquid crystalline polyester resin composition according to claim 1, wherein the aromatic diols is 4,4′

-dihydroxybiphenyl, aromatic hydroxycarboxylic acid is p-hydroxy benzoinc acid and the aromatic dicarboxylic acid is terephthalic acid, isophthalic acid, or a mixture of terephthalic acid and isophthalic acid.

4. The liquid crystalline polyester resin composition according to claim 3, wherein both of the liquid crystalline polyester resin (A) and the liquid crystalline polyester resin (B) comprise a structural repeating unit (I) derived from p-hydroxybenzoic acid, a structural repeating unit (II) derived from 4,4′

-dihydroxybiphenyl, a structural repeating unit (III) derived from terephthalic acid, and a structural repeating unit (IV) derived from isophthalic acid.

5. The liquid crystalline polyester resin composition according to claim 4, wherein a mole ratio of II/I is in a range of 0.2 to 1.0, a mole ratio of (III+IV)/II is in a range of 0.9 to 1.1, and a mole ratio of IV/III is in a range not lower than 0 to not higher than 1.

6. The liquid crystalline polyester resin composition according to claim 5, wherein a ratio of the mole ratio of IV/III (α

) of liquid crystalline polyester resin (A) to the mole ratio of IV/III (β

) of liquid crystalline polyester resin (B) (α

/β

) is in the range of 0.1 to 0.6.

7. The liquid crystalline polyester resin composition according to claim 1, wherein the fibrous inorganic filler is at least one selected from the group consisting of glass fiber, carbon fiber, wallastonite, aluminum borate, potassium titanate whisker.

8. The liquid crystalline polyester resin composition according to claim 1, wherein the plate-shaped inorganic filler is at least one selected from the group consisting of talc, mica and mixture of talc and mica.

9. A connector obtained by using the liquid crystalline polyester resin composition according to any one of claims 1 to 8.