Preformed yarn useful for forming composite articles and process for producing same

• US 5,206,085 A
• Filed: 05/13/1991
• Issued: 04/27/1993
• Est. Priority Date: 08/13/1987
• Status: Expired due to Term

• Current Assignee: Across Co., Ltd. (JMACS Japan Co. Ltd.)
• Original Assignee: Across Co., Ltd. (JMACS Japan Co. Ltd.)
• Inventors: Nakagawa, Takao, Ueda, Takuya, Tachibana, Masaharu, Namba, Shoko, Yamashita, Mihoko
• Primary Examiner(s): Ryan, Patrick J.
• Assistant Examiner(s): EDWARDS, NEWTON
• Application Number:
  US07/700,897
• Time in Patent Office: 715 Days
• Field of Search: 428/372, 428/373, 428/374, 428/375, 57/258, 57/401, 264/131, 264/136
• US Class Current: 428/372
• CPC Class Codes: B29B 15/12 of reinforcements of indefinite length
• CPC Class Codes: B29B 9/14 fibre-reinforced
• CPC Class Codes: B29C 48/04 Particle-shaped making granules B29B9/00
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/06 Rod-shaped
• CPC Class Codes: B29C 48/156 Coating two or more articles simultaneously
• CPC Class Codes: B29C 70/025 with particular filler
• CPC Class Codes: B29C 70/20 oriented in a single direction, e.g. roofing or other parallel fibres B29C70/083, B29C70/226 take precedence
• CPC Class Codes: B29C 70/542 Placing or positioning the reinforcement in a covering or packaging element before or during moulding, e.g. drawing in a sleeve
• CPC Class Codes: B29K 2105/251 Particles, powder or granules expandable particles B29K2105/046
• CPC Class Codes: D02G 3/40 Yarns in which fibres are united by adhesives; Impregnated yarns or threads
• CPC Class Codes: D02G 3/447 Yarns or threads for specific use in general industrial applications, e.g. as filters or reinforcement
• CPC Class Codes: D10B 2505/02 Reinforcing materials; Prepregs
• CPC Class Codes: Y10T 428/2927 including structurally defined particulate matter
• CPC Class Codes: Y10T 428/2929 Bicomponent, conjugate, composite or collateral fibers or filaments [i.e., coextruded sheath-core or side-by-side type]
• CPC Class Codes: Y10T 428/2931 Fibers or filaments nonconcentric [e.g., side-by-side or eccentric, etc.]
• CPC Class Codes: Y10T 428/2933 Coated or with bond, impregnation or core

Abstract

A preformed yarn useful for forming composite articles is disclosed which includes a core of a multiplicity of fibers, fine powder provided in the interstices between the fibers, and a flexible sleeve formed of a thermoplastic resin and surrounding the core. The fine powder is formed of a material which neither melts nor reacts with the thermoplastic resin at a temperature up to 450° C. and at a temperature up to the melting point of the thermoplastic resin. The incorporation of the fine powder between the fibers is effected by injecting fine powder-containing air from a jet nozzle and blowing the air against a bundle of the fibers.

Claims

1. A preformed yarn consisting essentially of:

a core of multiplicity of fibers, said core being 30-70% of the total volume of the preformed yarn;

a fine powder of carbon, metal or metal compound provided in the interstices between said fibers; and

a flexible sleeve formed of a thermoplastic resin and surroundings said core;

said fine powder being present in an amount constituting about 0.01 to about 10% based on the volume of said fibers and being formed of a material which neither melts nor reacts with said thermoplastic resin neither at a temperature up to 450°

C. nor at a temperature up to the melting point of said thermoplastic resin.

2. A preformed yarn according to claim 1, wherein said flexible sleeve has a thickness of about 5 to 1000 μ

m.

3. A preformed yarn according to claim 1, wherein said powder is graphite powder, carbon black powder, alumina powder, silica powder, calcium carbonate powder, calcium silicate powder, molybdenum dioxide powder, molybdenum disulfide powder, quartz powder, glass powder, hollow glass powder or tetrafluoroethylene powder.

4. A preformed yarn according to claim 1, wherein said fibers are formed of a material which does not melt at a temperature up to the melting point of said thermoplastic resin.

5. A preformed yarn according to claim 4, wherein said fibers are reinforcing fibers selected from carbon fibers, glass fibers, aramide fibers, boron fibers, ceramic fibers and metal fibers.

6. A preformed yarn according to claim 4, wherein said powder has an average specific surface area diameter of not greater than one third of the diameter of said fibers.

7. A preformed yarn according to claim 6, wherein said powder has an average specific surface area diameter of 15 μ

m or less.

8. A preformed yarn according to claim 1, wherein said powder is graphite powder, carbon black powder, alumina powder, silica powder, calcium carbonate powder, calcium silicate powder, molybdenum dioxide powder, molybdenum disulfide powder, quartz powder, glass powder or hollow glass powder.