Polyplastics Co., Ltd.

Other

Kazufumi Watanabe

Hiroki Fukatsu

Hirokazu Ohshiba

Raita Nishikawa

Masayuki Sakai

Takayuki Ishikawa

Hiroyuki Wakabayashi

Tomohiro Monma

Toru Katsumata

Akihide Shimoda

Toshio Shiwaku

Seiji Kayukawa

Kei Aoki

Tetsuya Hirose

Kenichi Yasusaka

A polyoxymethylene resin composition from which formaldehyde is generated in a reduced amount upon molding, without carrying out a stabilization treatment for stabilizing an unstable terminal group in a crude oxymethylene copolymer. A hindered phenol-type antioxidant agent and an ethylene-(methacrylic acid) copolymer resin or an ethylene-(acrylic acid) copolymer resin or a salt thereof are melted and kneaded together to produce a polyoxymethylene resin composition without carrying out a stabilization treatment for stabilizing an unstable terminal group in a crude oxymethylene copolymer for which a polymerization catalyst is deactivated after the completion of copolymerization, and in which the unstable terminal group is not yet stabilized. When the polyoxymethylene resin composition is extrusion-molded, the discoloration of a molded product or the deterioration in properties of the molded product can be prevented for a long period of time. The resulting polyoxymethylene resin composition is suitable for forming an extrusion-molded article.

Method for producing polyoxymethylene resin composition

The present invention provides a planar connector having excellent performances including flatness, warp-deformation resistance, and heat resistance, being capable of responding to shape changes in recent planar connectors. Specifically, the planar connector is composed of a composite resin composition comprises (A) a liquid crystalline polymer containing 55% by mole or less of p-hydroxy benzoic acid residue and having a melting point of 330&#xb0; C. or higher, (B) a plate-like inorganic filler, and (C) a fibrous filler having a weight average fiber length within a range of 250 to 600 &#x3bc;m, the amount of (B) component being 25 to 35% by weight to the total composition, the amount of (C) component being 10 to 25% by weight to the total composition, the sum in total of (B) component and (C) component being 40 to 50% by weight to the total composition, wherein the connector has a lattice structure inside an outer frame, and has an opening inside the lattice area, and wherein the pitch interval of the lattice area is 1.5 mm or less, and the ratio of the thickness of the thickness of the lattice area to the outer frame area is 0.8 or less.

Planar connector

The present invention provides a liquid crystalline polyester resin composition which imparts a good mold-releasability during molding and further is improved in heat resistance. Specifically, with 100 parts by weight of a liquid crystalline polyester resin is added 0.001 to 1 part by weight of a fatty acid ester which is a tetraester of pentaerythritol and a C10 to C32 higher fatty acid and has an acid value ranging from 0.01 to 0.5 and a hydroxyl value ranging from 0.01 to 5.

Liquid crystalline polyester resin composition

The object is to provide a method for manufacturing liquid crystalline resin composition having a hollow filler and a fibrous filler using a common melting-kneading extruder to maintain well-balanced relation between the residual percentages of hollow filler and the fiber length, which balance could not be attained in the prior art. A liquid crystalline resin composition having 5 to 30% by weight of hollow filler and 5 to 30% by weight of fibrous filler is manufactured using a melting-kneading extruder provided with a screw. (1) The liquid crystalline resin is fed from a main feed port located at upstream side in the extruding direction, while a hollow filler and a fibrous filler are fed from a side feed port located at downstream side in the extruding direction. The manufacture is conducted under the specific conditions between (2) Las the ratio L/D in which D is the screw diameter and L is the distance between the position of the side feed port and the position where the internal pressure of the extruder reaches 0.1 MPa; (3) Las the ratio L/D in which D is the screw diameter and L is the length of maintaining the internal pressure of the extruder at or above 0.1 MPa after feeding the hollow filler and the fibrous filler; and (4) La as the ratio L/D in which D is the screw diameter and L is the length of the resin plasticizing zone.

Method for manufacturing liquid crystalline resin composition of reduced density

The present invention provides a very thin planar connector having 2 mm or smaller pitch interval at the lattice area and 0.5 mm or smaller thickness of the lattice area, giving excellent performance in the whole performances such as moldability, flatness, warp-deformation, and heat resistance. A planar connector having a lattice structure within an outer frame is molded by using (C) a resin composition prepared by compounding (A) a liquid-crystalline polymer with (B) a fibrous filler, while the relation between the compounding quantity and the weight-average length of (B) the fibrous filler is controlled to a specified range.

An object of the present invention is to economically produce a resin composition pellet with the degradation of resin suppressed, by using an ordinary extruder, the resin composition pellet being filled with a desired filling amount of a uniformly compounded fibrous filler, and having a required weight average fiber length, in particular, to produce a resin composition pellet used for a socket of a planar socket pin in which the pitch interval of a lattice area of a semiconductor device is 2.0 mm or less, the thickness of the lattice area is 0.5 mm or less, and the height of the socket is 5.0 mm or less. To achieve the object, in supplying 80 to 55% by weight of resin and 20 to 45% by weight of the fibrous filler with a weight average fiber length of 1 mm or more to an extruder to produce a resin composition pellet in which a weight average fiber length of a fibrous filler is 180 to 360 &#x3bc;m, a part of an amount (x) of the resin is supplied through a main feed port of the extruder, and the fibrous filler and a remaining amount (1&#x2212;x) of the resin are supplied through a side-feed port so that x/(1&#x2212;x) becomes 50/50 to 10/90% by weight.

Method for producing a pellet from a fiber-filled resin composition and injection-molded products thereof

To provide a thermoplastic polyester resin composition which has a very good durability to alkaline solutions for a long period of time. That is, a thermoplastic polyester resin composition, wherein a thermoplastic polyester resin (A) is compounded with 1-25% by weight (in the total composition) of impact resistance rendering materials (B), 0.1-15% by weight (in the total composition) of a silicone compound and/or a fluorine compound (C), 1-50% by weight (in the total composition) of an inorganic filler (D), and 0.1-10% by weight of at least one polyfunctional compound (E) selected from the group consisting of an epoxy compound, an isocyanate compound and a carboxylic acid dianhydride. A molded article of the present invention has anti-stress properties even in a weld part thereof.

Growing community of inventors

Fuji, Japan

Kazufumi Watanabe