Liquid crystal polyester resin composition for camera module

• US 8,142,683 B2
• Filed: 03/24/2009
• Issued: 03/27/2012
• Est. Priority Date: 03/28/2008
• Status: Active Grant

• Current Assignee: ENEOS Corporation (ENEOS Holdings, Inc.)
• Original Assignee: JX Nippon Oil & Energy Corporation (ENEOS Holdings, Inc.)
• Inventors: Kitai, Toru, Murouchi, Satoshi, Nakayama, Toshio
• Primary Examiner(s): WU, SHEAN CHIU
• Application Number:
  US12/933,808
• Publication Number:
  US 20110114883A1
• Time in Patent Office: 1,099 Days
• Field of Search: 252/299.01, 252/299.5, 252/299.67, 524/424, 524/451, 524/493, 524/494, 524/495, 524/496
• US Class Current: 252/299.01
• CPC Class Codes: C08K 3/04 Carbon
• CPC Class Codes: C08K 7/14 Glass
• CPC Class Codes: C08K 7/26 Silicon- containing compounds
• CPC Class Codes: C08K 7/28 Glass
• 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: G03B 9/08 Shutters

Abstract

A liquid crystal polyester resin composition includes, based on 100 parts by mass of a liquid crystal polyester, 15 to 60 parts by mass of talc having a number average particle size of 10 to 50 μm, 25 to 50 parts by mass of a glass fiber having a number average fiber length of 100 to 200 μm and a number average fiber diameter of 4 to 8 μm, and 2 to 10 parts by mass of carbon black, wherein a melt viscosity as determined at a shear rate of 100 sec⁻¹ at 370° C. is 10 to 100 Pa·S and a deflection temperature under load is 220° C. or more. The liquid crystal polyester resin composition is used to provide a liquid crystal polyester resin composition for a camera module, having good heat resistance, rigidity, strength, and moldability, and also an excellent surface exfoliation property in a well balanced manner and being capable of being surface mounted (SMT).

Claims

1. A liquid crystal polyester resin composition for a camera module, characterized by comprising, based on 100 parts by mass of a liquid crystal polyester, 15 to 60 parts by mass of talc having a number average particle size of 10 to 50 μ

m, 25 to 50 parts by mass of a glass fiber having a number average fiber length of 100 to 200 μ

m and a number average fiber diameter of 4 to 8 μ

m, and 2 to 10 parts by mass of carbon black, wherein a deflection temperature under load is 220°

C. or more and a melt viscosity at a shear rate of 100 sec<sup>−

1</sup> at 370°

C. is 10 to 100 Pa·

S.

2. The liquid crystal polyester resin composition according to claim 1, characterized in that a number of exfoliations from a surface of a molded article by injection molding according to the following definition is 250 or less,

number of exfoliations=number of particles in 10 mL of pure water having a maximum diameter in the range of 2 μ

m or more after subjecting 2 cylindrical injection molded articles having a threaded structure with a 0.3 mm pitch and a 0.2 mm groove depth on an inner side of the article with 7 mm (outer diameter)×

6 mm (inner diameter)×

4 mm (height) to ultrasonic cleaning for 30 seconds at a power of 40 kHz and 480 W in 266 mL of pure water.

3. The liquid crystal polyester resin composition according to claim 1, characterized in that a weld strength of a molded article by injection molding is 30 MPa or more.

4. A part for a camera module produced from the liquid crystal polyester resin composition according to claim 1, by injection molding.

5. The liquid crystal polyester resin composition according to claim 2, characterized in that a weld strength of a molded article by injection molding is 30 MPa or more.

6. A part for a camera module produced from the liquid crystal polyester resin composition according to claim 2, by injection molding.

7. A part for a camera module produced from the liquid crystal polyester resin composition according to claim 3, by injection molding.