Reinforcing cord for rubber reinforcement and rubber product including the same
A reinforcing cord of the present invention is a reinforcing cord for rubber reinforcement. The reinforcing cord includes a carbon fiber strand ( 11 ) and a plurality of glass fiber strands ( 12 ) arranged around the carbon fiber strand ( 11 ). The present invention makes it possible to obtain a reinforcing cord having sufficient tensile strength for reinforcing rubber products as well as high dimensional stability and bending fatigue resistance.
1. A rubber belt comprising a rubber part and a reinforcing cord embedded in the rubber part, wherein the reinforcing cord comprises a carbon fiber strand and a plurality of glass fiber strands arranged around the carbon fiber strand, and
a coating layer containing a rubber is formed on the carbon fiber strand.
2. The rubber belt according to claim 1 , wherein the total cross section of the carbon fiber strand is in a range of 20% to 80% of the total of the total cross section of the carbon fiber strand and the total cross section of the glass fiber strands.
3. The rubber belt according to claim 1 , wherein the carbon fiber strand has a twist number of 5.0 times/25 mm or less.
4. The rubber belt according to claim 1 , wherein surfaces of the glass fiber strands have been treated with a treatment solution containing, as its main components, a rubber latex and a condensate of resorcinol and formalin.
5. The rubber belt according to claim 1 , wherein the glass fiber strands have been primarily twisted at a twist number in a range of 0.25 to 5.0 times/25 mm.
6. The rubber belt according to claim 5 , wherein the reinforcing cord has been finally twisted in an opposite direction to a direction in which the glass fiber strands have been primarily twisted.
7. The rubber belt according to claim 1 , wherein the carbon fiber strand and the glass fiber strands have been primarily twisted in the same direction.
8. The rubber belt according to claim 1 , wherein a final twist number of the reinforcing cord is in a range of 0.5 to 10 times/25 mm.
9. The rubber belt according to claim 1 , wherein a surface of the reinforcing cord is covered with rubber.
10. The rubber belt according to claim 1 , wherein the coating layer is formed using a treatment solution containing a rubber latex and a mixture of an initial condensate of resorcinol and formalin.