Plastic and nonmetallic article shaping or treating: processes – Forming continuous or indefinite length work – Shaping by extrusion
Reexamination Certificate
2000-05-16
2002-06-11
Tentoni, Leo B. (Department: 1732)
Plastic and nonmetallic article shaping or treating: processes
Forming continuous or indefinite length work
Shaping by extrusion
C264S211150, C264S211170, C264S237000
Reexamination Certificate
active
06403006
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to polyester multifilament yarn with high modulus and low shrinkage particularly useful for the textile reinforcement of tires. The yarn of the invention provides high treated cord tenacity while maintaining or increasing treated cord dimensional stability when compared to prior art yarns. A process for,production of the multifilament polyester yarn is an aspect of the invention.
2. Description of the Prior Art
Polyethylene terephthalate filaments of high strength are well known in the art and are commonly utilized in industrial applications including tire cord for rubber reinforcement, conveyor belts, seat belts, V-belts and hosing.
Continued improvement in high strength industrial yarns particularly suited for use as fibrous reinforcement in rubber tires is an ongoing need in the industry. In particular, the improvement of treated cord tenacity and dimensional stability are desired objectives. U.S. Pat. No. 4,101,525 to Davis et al. provides an industrial strength multifilament polyester earn with high initial modulus and low shrinkage. Although Davis et al. does not provide treated cord data, it is commonly known that compared to conventional tire cords such yarn provides a reduced tenacity when the yarn is converted to the treated tire cord. Additionally, rapid cooling of the filament immediately after emerging from the spinneret can result in excessive filament breakage and thus yield yarn with poor mechanical quality. U.S. Pat. No. 4,491,657 to Saito et al. discloses high modulus, low shrinkage polyester yarn, but requires a low terminal modulus to achieve good yarn to treated cord conversion efficiency for such dimensionally stable yarns. The low terminal modulus is carried over into the treated cord and results in a lower tenacity than the high terminal modulus cords of the present invention. Also, as shown in
FIG. 8
, the process of Saito et al. requires high spinning speeds, which makes it difficult to process on-panel, i.e. a continuous spin-draw process.
SUMMARY OF THE INVENTION
Polyethylene terephthaleate yarn can be prepared by spinning under high stress conditions in the transition region between oriented-amorphous and oriented-crystalline undrawn yarns. The invention is accomplished by selection of process parameters to form an undrawn yarn that is a crystalline, partially oriented yarn with a crystallinity of 3 to 15 percent and a melting point elevation of 2 to 10° C. The spun yarn is then hot drawn to a total draw ratio between 1.5/1 and 2.5/1 with the resulting unique combination of properties: (A) a terminal modulus of at least 20 g/d, (B) a dimensional stability defined by E
4.5
+FS<13.5 percent, (C) a tenacity of at least 7 grams per denier, (D) a melting point elevation of 9 to 14° C., and (E) an amorphous orientation function of less than 0.75. The drawn yarn is twisted and plied to produce tire-cord and then treated with resorcinol-formaldehyde-latex. The resulting treated tire cord unexpectedly provides high tenacity in combination with improved dimensional stability.
REFERENCES:
patent: 3690362 (1972-09-01), Mago et al.
patent: 4101525 (1978-07-01), Davis et al.
patent: 4195052 (1980-03-01), Davis et al.
patent: 4251481 (1981-02-01), Hamlyn
patent: 4414169 (1983-11-01), McClary
patent: 4491657 (1985-01-01), Saito et al.
patent: 4690866 (1987-09-01), Kumakawa et al.
patent: 4827999 (1989-05-01), Yabuki et al.
patent: 4867936 (1989-09-01), Buyalos et al.
patent: 4975326 (1990-12-01), Buyalos et al.
patent: 5132067 (1992-07-01), Nelson et al.
patent: 5350632 (1994-09-01), Lang
patent: 0 080 906 (1983-06-01), None
patent: 0 089 912 (1983-09-01), None
patent: 169415 (1988-10-01), None
patent: 35-3104 (1960-04-01), None
patent: 46-28979 (1971-08-01), None
patent: 51-96521 (1976-08-01), None
patent: 58-203112 (1983-11-01), None
patent: S58-203112 (1983-11-01), None
patent: 59-116414 (1984-07-01), None
patent: 59-19812 (1986-01-01), None
Korean Patent Invalidation Trial Brief filed Oct. 8, 1998 by Korean Chemical Fiber Association.
Measurements and Analyses of Fibers by Ro-Soo Kim et al. dated 1990.
Korea Science Promotion Foundation Translation Series 53 Physical Polymer Science dated Mar. 1996.
Korean Industry Property Tribunal Decision dated Nov. 30, 1999.
After Appeal, First Korean Brief filed Apr. 21, 2000 by AlliedSignal Inc.
J. Shimizu et al., “High Speed (Melt) Spinning of Polyethylene Terephthalate Fibers and The Effect of Molecular Weight”, Seni Gakkaishi V 34 (1978).
G.W.Davis et al., “Polyester Fibers: Variants”, Fiber Producer, pp. 45-62 (Jun. 1984).
A. Roos, “Melt Spinning of PET Industrial Fibers”, Fiber Formation Symposium, ACS Meeting, Toronto, Canada (Jun. 5-10, 1988).
Richard Dean, “New Polyester Tire Cord Developments”, Polyester Textiles, Shirley Pub S51 (1988).
Opposition Statement by Rhone-Poulenc dated Feb. 22, 1993.
Opposition Statement by Hoechst dated Feb. 26, 1993.
Minutes of European Oral Proceedings dated Apr. 19, 1995.
Minutes of European Technical Board of Appeal Maintaining Patent dated Sep. 23, 1999.
Japanese Opposition Statement filed by Korean Synthetic Fiber Association dated Dec. 27, 1999.
Japanese Patent Office Decision on aforementioned Opposition dated Nov. 9, 2000.
H.H. George et al., “A Study of Structural Development in the High Speed Spinning of Poly(Ethylene Terephthalate)”, Polymer Engineering and Science, vol. 23 (2), 95 (1983).
“A Study of Structural Development in the High Speed Spinning of Poly(Ethylene Terephthalate)” by H.H. George, A. Holt, and A. Buckley; Polymer Engineering & Science Mid-Feb. 1983, vol. 23 No. 2, pp. 95-99.
“High Speed Spinning of Polyethylene Terephthalate (PETP) by Pneumatic Take-up. Physical and Mechanical Properties of Filaments” by G. Perez and C. Lecluse, International Chemifasertagung in Dornbirn Conference, Jun. 20-22, 1979, conference pp. 1-37.
International Search Report for PCT/US 89/02781 (Oct. 23, 1989).
Bheda Jayendra Hiralal
Nelson Charles Jay
Rim Peter Bryan
Turner James Michael
Allied-Signal Inc.
Andrews Virginia Szigeti
Brown Melanie L.
Criss Roger H.
Tentoni Leo B.
LandOfFree
Process of making dimensionally stable polyester yarn for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process of making dimensionally stable polyester yarn for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process of making dimensionally stable polyester yarn for... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2936592