WO1985002210A1

WO1985002210A1 - Steel cord

Info

Publication number: WO1985002210A1
Application number: PCT/JP1983/000410
Authority: WO
Inventors: Nobuhiro Sowa; Ritsuo Nakayasu
Original assignee: Sumitomo Rubber Industries, Ltd.
Priority date: 1983-11-14
Filing date: 1983-11-14
Publication date: 1985-05-23
Also published as: JPS6127519B1

Abstract

The space within a steel cord (10, 17) formed by tightly intertwining a plurality of steel strands is filled with a nonmetallic material (16, 25), such as rubber, plastic or organic fibers, to prevent the inclusion of air within the steel cord when it is embedded in rubber and bonded thereto by vulcanization, thereby preventing any corrosion as well as maintaining the dimensional stability of the cord.

Description

Description Name of Invention

Steal record

Technical field

The present invention relates to a steel cord for a tire, and particularly to a car for a tire.

Used for tire reinforcement such as scum, pelt layers, and bead reinforcement layers

Regarding the steel code used.

Background art

Steel cord has strength, modulus, heat resistance and fatigue resistance

Labor compared to other types of inorganic or organic fibers

It is better than the '

Tire wear resistance when used on scum or belt layers

, Durability, and handling stability. Here

Steel cord that has been used as reinforcement for tires since then

Twists several steel strands (3) as shown in Fig. 1.

A bundle of multiple strands (4)

The teal code (1) is configured. And the reinforcement is

A steel cord is embedded in rubber, and this is vulcanized and bonded.

The space formed between the steel wires

(2) The rubber does not flow sufficiently into the air and air remains.

You. So we can use such reinforcements in tire carcass

When used for the pelt layer,

The residual air inside the steel cord expands, causing local distortion.

Cause the separation of steel cord and rubber,

If the tire is incised and damaged, water will

OMPI

, First officer. ,

ΛΤ There is a problem in that the steel cord diffuses into the inner space of the steel cord and causes the steel cord to shrink. The following proposals have been made to solve this problem. (i) First, steel cord strands are twisted at intervals from each other, making it easier for rubber to penetrate inside the steel cord by forming an open cord (Japanese Patent Laid-Open No. 55-096992). ), But this has the drawback that the cord is easily stretched in the longitudinal direction, the rigidity is insufficient, and the dimensional stability is poor.

(ϋ) Also, as shown in Fig. 2, the inside of the steel cord (5) is filled with a non-metallic core (6), and the strands (7) that surround the steel cord (5) are twisted with a gap between them. There is a composite cord (Japanese Patent Publication No. 58-113) that is easy to stretch in the longitudinal direction and is inferior in dimensional stability like the open cord. In addition, the interface between pit metal and rubber, and the pit metal and steel At the interface between the strands, a gap is formed due to poor adhesion, which forms a capillary tube, and there is a problem that water enters.

(iii) Method of further dipping steel wire with rubber glue (Japanese Patent Application Laid-Open No. 54-909948) Method of coating steel wire in advance with rubber (Japanese Utility Model Application No. 56-70304) In addition, there is disclosed a method of opening the gap between steel wires and filling the inside with rubber (Japanese Patent Publication No. 56-1283884). Not suitable for the manufacturing process of o

Thus, the present invention provides a method for connecting a steel cord to rubber without deteriorating the modulus and dimensional stability of the steel cord. It proposes a steel cord with improved adhesion and prevention of occurrence.

Disclosure of the invention

The present invention relates to a non-metal inside a strand in which a plurality of steel strands are tightly stranded together and / or a cord in which the strands are closely stranded together. The steel cord or the strand is filled with pit metal, so that air remains. No steel protection and improved adhesion between steel cord and rubber.

BRIEF DESCRIPTION OF THE FIGURES

1 and 2 are cross-sectional views of a conventional steel cord, FIGS. 3 and 4 are cross-sectional views of the steel cord of the present invention, FIG. 5 is a test piece for measuring the air permeability of the cord, FIG. Fig. 6 is a schematic diagram of the measurement method, and Fig. 7 is a graph showing the relationship between cord stress and elongation.

BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the present invention will be described below with reference to the attached documents.

In FIG. 3 showing a sectional view of the steel cord of the present invention, the steel cord (10) has five steel strands (11) (12) (13) (14) (15) ). The steel strands are in close contact with each other, forming a lumen (16) which is almost closed from the outside, and this lumen is filled with a non-metallic core material. Here the non-metallic core material Rubber, plastic, organic fiber, etc. are used. For example, rubber includes natural rubber, polysoprene rubber, styrene-butadiene copolymer, butyl rubber, ethylene-propylene rubber, chloroprene rubber, butadiene rubber, and the like. Propylene, vinyl chloride, etc., and organic fibers such as nylon, polyester, rayon, and aramide. In particular, when a material that melts in the temperature range of 100 T: to 180 T of these core materials, for example, polyethylene or polypropylene, the steel cord is vulcanized in the embedded rubber. In the process of bonding, the material melts and penetrates the entire inner space of the steel cord to prevent air from remaining. Here, the melting points of organic fibers are as shown in Table 1.

When organic fibers are used for the S material, it is difficult to completely fill the entire lumen because the melting points of many materials are 180 t: or more. Therefore, it is preferable to coat the surface of the organic fiber with rubber, rubber paste or plastic having high fluidity under heating. In addition, organic fibers are generally hygroscopic, and this moisture diffuses into the steel cord, causing the steel cord to ripen. Therefore, it is desirable that the moisture content (JISL-107) of the organic fiber cord be 0.2% or less.

Next, the steel cord (10) of the invention has the closest packing of the steel elements (1 1), (1 2), (1 3), (1 4), and (15). And the elongation in the longitudinal direction is extremely small. So this When steel cord is used as a reinforcing material for a tire, a tire having excellent dimensional stability and excellent uniformity can be obtained without the cord being stretched in the tire manufacturing process. Table 1

2 0

Material Melting, 6 5 1. At RH

Moisture percentage

Polyethylene 1 25 to 1 3 5 0.0%

Polypropylene 16 5 to 17 3 0.0%

Vinylidene 16 5 to 18 5 0.0%

Polyvinyl chloride 0,0% at 200 to 210

Polyester 25 to 26 0 0.4%

Nylon 6 21 5 to 22 0. C 4.5% FIG. 4 shows a sectional view of another embodiment of the steel cord of the present invention. In the figure, the steel cord (17) is composed of six strands (19) consisting of three steel wires (18).

(20) (21) (22) (23) (24), and adjacent strands are arranged so as to be in contact with each other. And into the lumen in a lumen that is formed by the _c Note steel filaments each be sampled run-de inner core of non-metallic (2 5) are Takashi塡formed by these be sampled run-de The core can be filled.

The steel cord of the present invention usually has a twist pitch of 3 to 3.

It is in the range of 20 と, but if it is less than 3 nun, the strength and productivity of the cord will be significantly reduced, while exceeding 20 recitations

OTvfPI This is because the bending fatigue and convergence of the cord are reduced.

Strands with a diameter of 0.10 to 0.40 ram, 2 to 5 strands

It is manufactured by combining. In addition, the code of the present invention has a

Twist multiple strands of wire, or

Multiple strands of twisted strands are further burned

They can be configured together.

Radialta for passenger cars with tire size 1 6 5 S R 13

The five filaments shown in Table 3 (1

Steel with X5 structure and filament diameter 0.25 ram)

With cords of various intermediate elongation, twisted pitch 9.5 mm

A rubber buried in rubber with a 300% modulus of 100 kg / crf

Two rye were used and the carcass layer is shown in Table 3.

1500 d / 2 polyester ester with various physical properties

It is composed of a monoply using

Prototype tires under conditions and PCI conditions and evaluate their performance

The results are shown in Table 2. Examples of the present invention are all tires.

Characteristics, durability, generation of salt water, etc.

It is recognized that the properties are excellent overall. The bell

Intermediate elongation (PEL) of each brie used for the air layer and air

Table 3 shows the measurement results of the transmission amount. In addition, each steel coat

FIG. 7 shows the relationship between stress and elongation of the alloy.

(I) Unifo My tea

Load a tire filled with a rim and filled with an internal pressure of 2.0 kg / crf.

3 5 7 kg, press against the drum and rotate the tire and drum

Measure the change in stress in the horizontal and vertical directions with respect to the axle-

OMPI This was indexed as a relative value to Comparative Example 1. The smaller the index, the better.

(π) Degree of code generation after running salt water drum (%)

Drill holes with a diameter of 3 mm from the inner surface of the tire at four places in the tire circumferential direction and three places in the radial direction of the tread part at each position, a total of 12 places, and penetrate the tread surface. Assemble the tire into a rim and add 50% Occ of 10% salt water to the inside of the tire to fill the tire to the specified internal pressure. After running the tire for 20,000 kra under the conditions of the endurance test of US D0T standard FMVSS109, remove the tire tread from the breaker.

The average value obtained by dividing the length of って generated along the steel cord centering on the drill hole by the total length of the cord is defined as the steel code occurrence rate.

(NO) Breaker edge separation resistance

The tire after the running test with the saltwater drum was dismantled at the edge of the breaker before measuring the degree of occurrence of steel cord, and the length of the rubber crack growing from the breaker edge was measured.The value was relative to Comparative Example 1. Is indicated by an index. The larger the index, the smaller the crack length and the better. '

(2) Air permeability of code

A steel cord ply is cut out from the belt layer or the case of the prototype tire and molded and vulcanized into a test piece (28) having the shape shown in Fig. 5. In the figure, 26 is a vulcanized rubber plate and (27) is a steel cord ply. Therefore, the test piece (28) was inserted into the air injection hole (29) and the exhaust hole as shown in Fig. 6.

It is arranged in a measuring machine (31) having (30). Therefore When a back pressure of 2 kg / cnT is applied, 1 from the exhaust hole (30)

The volume of air coming out per minute was measured.

oim

, No Table 2 Comparative Example 1 Comparative Example Comparative Example j 3 Example 1 Example 2 Code Not 1 2 3 5 6 Pelt material 15 / 0.25 1 X 5 / 0.25 1 X 5/0 2 5 1 X 5 / 0.25 1 X 5 / 0.25

3 5 End 5 End 3 5 End 3 5 End 3 5 End Standard Medium Medium elongation Polyester mono-polyethylene Mono-monopolyethylene

(PEL 0.6%) Impartment Filament

ø 0.25 with Φ 0.18 with 2 0 0 d

Rubber glue Dip O n code Open code

.1 0 0 1 1 0 1 0 5 1 0 0 1 0 0 Driving stability

(5-point method, 5.0 is good) 3.0 2.5 2. 8 3.0 3.0 After running salt water drum

Occurrence rate (%) 8 0 7 4 0 2 4 1 0 Breaker resistance

Senorin a 1 0 0 i 4 0 1 3 0 1 0 0 9 5

Table 3

Note 1) Permeates between polyester and rubber and K of polyester filament.

Claims

The scope of the claims

1. A core in which multiple steel strands are twisted closely together

Strand or strands of multiple strands of steel

Inside the twisted code, which is substantially close to each other

Steel cord filled with non-metallic material.

2. The non-metallic core material is an organic fiber.

The steel cord shown.

3. The melting temperature of organic fiber is lower than the vulcanization temperature of the reinforced rubber product.

3. The steel cord according to claim 2, which is below.

4. The non-metallic core material is coated with unvulcanized rubber.

The steel cord according to item 1 in the range.

WIPO r