Hybrid cord and high-performance radial tire including the same

Patent metadata

Field	Value
Publication number	US-10035379-B2
Application number	US-201514884218-A
Country	US
Kind code	B2
Filing date	Oct 15, 2015
Priority date	Oct 21, 2014
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

A hybrid cord for a tire, a method of manufacturing the same, and a high-performance environment-friendly radial tire including the same are disclosed herein. The hybrid cord includes a high-modulus fiber ply and a low-modulus fiber ply. The hybrid cord has a stress-strain curve including an initial modulus section, an intermediate modulus section and a final modulus section. The initial modulus of the initial modulus section is higher than the intermediate modulus of the intermediate modulus section, and the final modulus of the final modulus section is higher than the intermediate modulus.

First claim

What is claimed is:

1. A hybrid cord, comprising:
a high-modulus fiber ply, and a low-modulus fiber ply;
wherein the hybrid cord has a stress-strain curve including an initial modulus section, an intermediate modulus section and a final modulus section, and wherein an initial modulus of the initial modulus section is higher than an intermediate modulus of the intermediate modulus section, and a final modulus of the final modulus section is higher than the intermediate modulus,
a ratio of the initial modulus to the intermediate modulus ranges from 1:0.4 to 1:0.85, and
a ratio of the initial modulus to the final modulus ranges from 1:4 to 1:9.

2. The hybrid cord of claim 1 , wherein the stress-strain curve of the hybrid cord includes first and second modulus transition points, the first transition point is present within a strain range from 0.003 to 0.025, and the second transition point is present within a strain range from 0.03 to 0.065.

3. The hybrid cord of claim 1 , wherein the hybrid cord includes a low-modulus fiber ply composed of aliphatic polyamide fiber, and at least one high-modulus fiber ply composed of one selected from the group consisting of aramid yarn, polyketone and wholly aromatic polyester, and combined with and twisted together with the low-modulus fiber ply.

4. The hybrid cord of claim 3 , wherein the hybrid cord includes 20-80% of 500-1600 denier aramid yarn and 80-20% of 400-1300 denier polyamide 66 yarn.

5. The hybrid cord of claim 3 , wherein the aramid yarn is high-strength aramid yarn whose tensile strength is equal to or higher than 16 g/D and whose Young's modulus ranges from 200 g/d to 1200 g/d.

6. The hybrid cord of claim 5 , wherein the hybrid cord has a twist factor α d ranging from 100 to 250, and the twist factor α d is expressed by the following Equation:

α
d

=

T
100

⁢

ρ
d

where α d is a denier-based twist factor, T is twists per meter (TPM), and ρ d is a fineness based on corrected weight of the hybrid cord on a denier basis.

7. A high-performance radial tire, wherein the hybrid cords set forth in claim 1 is used.

8. The high-performance radial tire of claim 7 , wherein the hybrid cord is used in a cap ply.

Assignees

• Hankook Tire Co Ltd

Inventors

• Lee Ji Wan
• Park Il Yong
• Hwang Kum Kang
• Lee Mi Jung
• Kim Sung Tae
• Cho Hyun Ran

Classifications

• B60C9/1821

  comprising discrete fibres or filaments · CPC title

• B60C9/0042

  Reinforcements made of synthetic materials · CPC title

• B60C2009/0035

  Reinforcements made of organic materials, e.g. rayon, cotton or silk · CPC title

• B60C9/005 Primary

  Reinforcements made of different materials, e.g. hybrid or composite cords · CPC title

• B60C2009/0092

  Twist structure · CPC title