Polybutylene terephthalate resin composition and thin molded article

Abstract

The present invention provides a polybutylene terephthalate resin composition which is free from bleeding and other problems, and improves the flowability (melt-flowability) while maintaining the characteristics such as mechanical strength or toughness. To 100 parts by weight of a composition composed of 50 to 90% by weight of (A) a polybutylene terephthalate resin and 10 to 50% by weight of (B) inorganic filler, is blended 0.05 to 5 parts by weight of (C) a glycerin fatty acid ester being composed of glycerin and/or a dehydrated condensate thereof and a fatty acid having 12 or more carbon atoms and having 200 or more hydroxyl value determined by the method specified in the description.

1 . A polybutylene terephthalate resin composition, obtained by blending 100 parts by weight of a composition composed of 50 to 90% by weight of (A) a polybutylene terephthalate resin and 10 to 50% by weight of (B) inorganic filler with 0.05 to 5 parts by weight of (C) a glycerin fatty acid ester being composed of glycerin and/or a dehydrated condensate thereof and a fatty acid having 12 or more carbon atoms having 200 or more hydroxyl value determined in accordance with the Japan Oil Chemists' Society Standard 2.4.9.2-71. 
   
   
       2 . The polybutylene terephthalate resin composition according to  claim 1 , wherein the fatty acid structuring said (C) glycerin fatty acid ester is selected from the group consisting of lauric acid, stearic acid, or behenic acid. 
   
   
       3 . The polybutylene terephthalate resin composition according to  claim 1 , wherein said (B) inorganic filler is glass fiber. 
   
   
       4 . The polybutylene terephthalate resin composition according to  claim 1 , having a determined melt viscosity of 130 Pa·s or less at a shear rate of 1000 sec −1  at a temperature of 260° C. 
   
   
       5 . A thin-walled molded article comprising the polybutylene terephthalate resin composition according to  claim 1 , having a flow length of 40 mm or more at a thickness of 0.5 mm following injection molding a cylinder temperature of 260° C. and at a mold temperature of 65° C. 
   
   
       6 . The thin-walled molded article according to  claim 5 , having a position with a thickness of 0.5 mm or less at a part of said molded article. 
   
   
       7 . The thin-walled molded article according to  claim 6 , being a switch, a capacitor, a connector, an integrated circuit (IC), a relay, a resister, a light-emitting diode (LED), a coil bobbin, and a peripheral device thereof or a housing thereof. 
   
   
       8 . The polybutylene terephthalate resin composition according to  claim 2 , having a determined melt viscosity of 130 Pa·s or less at a shear rate of 1000 sec −1  at a temperature of 260° C. 
   
   
       9 . The polybutylene terephthalate resin composition according to  claim 3 , having a determined melt viscosity of 130 Pa·s or less at a shear rate of 1000 sec −1  at a temperature of 260° C. 
   
   
       10 . A thin-walled molded article comprising the polybutylene terephthalate resin composition according to  claim 2 , having a flow length of 40 mm or more at a thickness of 0.5 mm following injection molding a cylinder temperature of 260° C. and at a mold temperature of 65° C. 
   
   
       11 . A thin-walled molded article comprising the polybutylene terephthalate resin composition according to  claim 3 , having a flow length of 40 mm or more at a thickness of 0.5 mm following injection molding a cylinder temperature of 260° C. and at a mold temperature of 65° C. 
   
   
       12 . A thin-walled molded article comprising the polybutylene terephthalate resin composition according to  claim 4 , having a flow length of 40 mm or more at a thickness of 0.5 mm following injection molding a cylinder temperature of 260° C. and at a mold temperature of 65° C. 
   
   
       13 . A thin-walled molded article comprising the polybutylene terephthalate resin composition according to  claim 8 , having a flow length of 40 mm or more at a thickness of 0.5 mm following injection molding a cylinder temperature of 260° C. and at a mold temperature of 65° C. 
   
   
       14 . A thin-walled molded article comprising the polybutylene terephthalate resin composition according to  claim 9 , having a flow length of 40 mm or more at a thickness of 0.5 mm following injection molding a cylinder temperature of 260° C. and at a mold temperature of 65° C. 
   
   
       15 . The thin-walled molded article according to  claim 10 , having a position with a thickness of 0.5 mm or less at a part of said molded article. 
   
   
       16 . The thin-walled molded article according to  claim 11 , having a position with a thickness of 0.5 mm or less at a part of said molded article. 
   
   
       17 . The thin-walled molded article according to  claim 12 , having a position with a thickness of 0.5 mm or less at a part of said molded article. 
   
   
       18 . The thin-walled molded article according to  claim 15 , being a switch, a capacitor, a connector, an integrated circuit (IC), a relay, a resister, a light-emitting diode (LED), a coil bobbin, and a peripheral device thereof or a housing thereof. 
   
   
       19 . The thin-walled molded article according to  claim 16 , being a switch, a capacitor, a connector, an integrated circuit (IC), a relay, a resister, a light-emitting diode (LED), a coil bobbin, and a peripheral device thereof or a housing thereof. 
   
   
       20 . The thin-walled molded article according to  claim 17 , being a switch, a capacitor, a connector, an integrated circuit (IC), a relay, a resister, a light-emitting diode (LED), a coil bobbin, and a peripheral device thereof or a housing thereof.