KR101878781B1 - An Excellent Fatigue Resistance Tire Cord using Nylon 6,6 or Nylon 6 and Aramid, and Radial Tires Produced by the Same - Google Patents

Abstract

The present invention relates to a method for producing a hybrid dipped cord using nylon 6.6 yarn and aramid yarn, comprising the steps of adjusting a tension applied to a raw cord, adjusting a heat treatment temperature, and adjusting a heat treatment time, The present invention relates to a method of producing a dipped cord in which nylon 6.6 yarn and aramid yarn are preliminarily formed, and a raw cord made of the same is heat treated while being dipped in an adhesive to further shrink the nylon 6.6 yarn.
Another object of the present invention is to provide a method of manufacturing a cigarette pneumatic radial tire having a certain degree of fatigue resistance such that the raw cord using the nylon 6.6 yarn and the aramid yarn is dipped in a dipping solution and then heat- Or a hybrid dip code for a cap ply layer.
In the present invention, when twisted yarns of aramid yarn and nylon yarn are kept at the same time, the nylon yarn is shrunk by subjecting the nylon yarn to heat treatment after the production of the cord, and the aramid yarn is longer than the nylon yarn per unit length So that fatigue can be increased. According to the present invention, it is possible to overcome the disadvantage of difficulty in deformation in the mold with high modulus when the aramid is used alone, and to improve the low fatigue resistance and adhesion which are problems in using aramid alone, 6.6 alone, it is possible to manufacture high performance tires by improving the low modulus and heat resistance which are problematic.

Description

(An Excellent Fatigue Resistance Tire Cord Using Nylon 6,6 or Nylon 6 and Aramid, and Radial Tires Produced by the Same) having excellent fatigue resistance using nylon 6.6 or nylon 6 yarn and aramid yarn,

The present invention relates to a high-strength tire cord using nylon 6.6 or nylon 6 yarn and an aramid yarn, and a radial pneumatic tire using the same.

In recent years, the performance of tires has been continuously improved according to improvement of the road environment and the performance of the vehicle. Especially, as the weight of the vehicle increases and the limit speed increases, safety is more importantly considered as a quality factor of the tire. The safety standards of tires are also being changed in accordance with the increasing demand for safety of tires. Researches on methods for imparting safety of tires in the tire industry are also being actively conducted.

Polyethylene terephthalate is widely used as an air inlet radial tire, and more particularly, as a carcass ply material of air inlet radial tires having a flatness ratio of 0.65 to 0.82. In addition, a flat flat tire having a low flatness ratio, more specifically, a flatness ratio of less than 0.70 Rayon is used as a carcass ply reinforcement of high-speed air inlet radial tires.

In recent years, some of polyethylene naphthalate has been used for radial tires having a low flatness ratio at high speed. However, polyethylene naphthalate is superior to polyethylene terephthalate in terms of high temperature property and shape stability, but its price is high and its application is restricted. U.S. Patent No. 6,601,378 proposes a hybrid cord made by twisting a wound yarn of polyethylene terephthalate and polyethylene naphthalate, respectively. Polyethylene naphthalate fibers have a significantly higher modulus than polyethylene terephthalate fibers. Due to such differences in physical properties, when one of each of the wound yarns of polyethylene terephthalate and polyethylene naphthalate is twisted, it causes unevenness of tension in the raw cord. Due to such a problem, the strength utilization ratio at the time of twisting and dipping is rapidly deteriorated.

Generally, yarn twisting conditions are the same when twisted yarns are produced by twisting yarns of the same kind, but in the case of hybrid yarns, the twist condition of each yarn can be set differently to control the properties of the raw cord. In the conventional technology, the properties of raw cord are changed by imparting softener to the yarn differently in the production of hybrid cord. In this case, when the former is applied to a yarn having a high modulus and a short yarn, the yarn is given less twist of the yarn, When the yarn having the same modulus as that of the yarn is given to the lower yarn, the yarn having a high modulus after twisting is given a twist in the twisting direction of the yarn, while the yarn having a low modulus is not twisted, It has the effect of increasing fatigue. However, this is applicable only to the spinning machine (DRT, RT) to which the post-spinning is given, and there is a problem that it can not be used in the Direct Cabler spinning machine in which the up and down spinning occurs simultaneously.

U.S. Patent No. 6601378

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art described above, and it is an object of the present invention to provide a method of manufacturing a hybrid cord using nylon 6.6 yarn and aramid yarn, a method of controlling tension applied to a raw cord, Nylon 6.6 or nylon 6 yarn and aramid yarn by using at least one method selected from the group consisting of nylon 6.6 or aramid yarn, And to provide a method of producing a dip cord in which nylon 6 yarns are further contracted. Thus, when dip cords are formed, hybrid dipped cords are produced, which are characterized by longer aramid yarns compared to nylon 6.6 yarns.

Another object of the present invention is to provide a method for producing a nylon 6.6 or nylon 6 yarn by dipping a raw cord using the nylon 6.6 or nylon 6 yarn and an aramid yarn in a dipping solution and then heat- To provide a hybrid dip code for a carcass ply or cap ply layer of radial tires.

According to a preferred embodiment of the present invention, the hybrid dipped cord comprises a raw cord having a single nylon 6.6 or nylon 6 yarn and one aramid yarn leading each other and combining them; And the raw cord is dipped in a dipping solution and then heat-treated to heat-shrink the nylon 6.6 or nylon 6 yarn so that the length of the nylon 6.6 yarn is shorter than that of the aramid yarn.

According to another preferred embodiment of the present invention, the hybrid dipped cord is heat-treated so that the length of the nylon 6.6 or nylon 6 yarn is shorter than that of the aramid yarn so that the heat shrinkage can be controlled by controlling the tension applied to the raw cord, And a method of controlling the heat treatment time.

According to another preferred embodiment of the present invention, the hybrid dipped cord is characterized in that the aramid yarn is 5 to 100 mm / m longer than the nylon 6.6 or nylon 6 yarn when the dipped cord is finished.

According to another preferred embodiment of the present invention, the hybrid dipped cord is characterized in that the dipped cord is nylon 6.6 or aramid yarn 10 to 30 mm / m longer than nylon 6 yarn.

According to another preferred embodiment of the present invention, the hybrid dipped cord is characterized by having an internal fatigue of 85% or more.

According to a preferred embodiment of the present invention, a method of manufacturing hybrid dipped cords for radial pneumatic tires is characterized in that a single nylon 6.6 or nylon 6 yarn and a single aramid yarn are twisted by applying a twist of 200 to 500 TPM yarns each, ; Folding the twisted yarn in two, and twisting the twisted yarn in a number of 200 to 500 TPM to produce a cord; And dipping the raw cord in a dipping solution followed by heat treatment to heat-shrink the nylon 6.6 or nylon 6 yarn so that the length of the nylon 6.6 yarn is shorter than that of the aramid yarn.

According to another preferred embodiment of the present invention, the method of manufacturing hybrid dipped cords for radial pneumatic tires further comprises shrinking nylon 6.6 or nylon 6 yarns in the heat treatment step, a method of controlling tension applied to the raw cord, A method of adjusting a heat treatment time, and a method of controlling a heat treatment time.

According to another preferred embodiment of the present invention, a method of manufacturing a hybrid dipped cord for a radial pneumatic tire is characterized in that the tension is controlled through the speed of the feed roller and the winding roller, the heat treatment temperature is 130 to 240 占 폚, Seconds.

According to another preferred embodiment of the present invention, a method of manufacturing a hybrid dipped cord for a radial pneumatic tire is characterized in that the aramid yarn is 5 to 100 mm / m longer than the nylon 6.6 or nylon 6 yarn when the dipped cord is finished.

According to another preferred embodiment of the present invention, a method of manufacturing a hybrid dipped cord for a radial pneumatic tire is characterized in that the dipped cord is nylon 6.6 or aramid yarn 10 to 30 mm / m longer than nylon 6 yarn.

According to another preferred embodiment of the present invention, the hybrid dipped cord for producing a radial pneumatic tire is characterized in that the fineness of nylon 6.6 or nylon 6 yarn and aramid yarn is 500 to 3000 denier, respectively.

According to a preferred embodiment of the present invention, there is provided a belt comprising: a pair of parallel bead cores; at least one radial carcass layer wound around the bead cores; a belt layer laminated on the outer circumferential side of the carcass layer; A radial pneumatic tire comprising a belt reinforcing layer in the direction comprises a hybrid dipped cord as shown above for a carcass ply or belt layer, and may be used as one or two layers.

In the present invention, when twisted yarns of aramid yarn and nylon yarn are kept at the same time, the nylon yarn is shrunk by subjecting the nylon yarn to heat treatment after the production of the cord, and the aramid yarn is longer than the nylon yarn per unit length So that fatigue can be increased. In the tensile test, the initial deformation induces low modulus by nylon, and the high modulus can be generated from the section where aramid begins to receive the force. Thus, the operation of inflating the green tires into the bladder in the mold during vulcanization So that the tire can be easily deformed and the tire can be easily manufactured. According to the present invention, it is possible to overcome the disadvantage of difficulty in deformation in the mold with high modulus when the aramid is used alone, and to improve the low fatigue resistance and adhesion which are problems in using aramid alone, It is possible to manufacture a high-performance tire by improving low modulus and heat resistance which are problematic when used alone.

Fig. 1 schematically shows a spinning and drawing process of nylon 6.6 yarn or nylon 6 yarn according to the present invention.
Fig. 2 schematically shows a manufacturing process of an aramid yarn according to the present invention.
Fig. 3 schematically shows a structure of a tire for a passenger car produced by using the hybrid dipped cord according to the present invention in a carcass layer or a cap ply layer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

The aramid yarn and the nylon 6.6 or nylon 6 yarn for the production of the hybrid dipped cord according to the present invention are produced through the following process.

First, a manufacturing method of nylon yarn used in the present invention will be described in detail with reference to the accompanying drawings.

The nylon used in the production of the hybrid tire cord of the present invention contains an amide group having a strong polarity in the main chain and has a stereoregularity and a symmetry and is crystalline. Generally, a polyamide refers to a generic term of a polymer linked by an amide bond (-CONH-), which can be obtained by condensation polymerization of a diamine and a dicarboxylic acid. Polyamides are characterized by amide bonds in the molecular structure, and their physical properties vary depending on the ratio of amide groups. For example, when the ratio of amide groups in the molecule is increased, specific gravity, melting point, absorbency, rigidity and the like are increased.

In addition, polyamide is a material used in a wide range of fields such as clothing, tire cord, carpet, rope, computer ribbon, parachute, plastic and adhesive due to its excellent resistance to corrosion, abrasion resistance, chemical resistance and insulation.

Generally, polyamides are classified into aromatic polyamides and aliphatic polyamides. Representative aliphatic polyamides include nylon. Nylon is originally a trademark of DuPont, Inc., but is now used as a generic name.

Nylon is a hygroscopic polymer and is sensitive to temperature. Representative nylons include nylon 6, nylon 6.6, and nylon 46.

First, nylon 6 is characterized by excellent heat resistance, moldability and chemical resistance, and is produced by ring-opening polymerization of ε-caprolactam in order to produce it. Nylon 6 means that caprolactam has 6 carbon atoms.

(Scheme 1) Nylon 6 polymerization of caprolactam

On the other hand, nylon 6.6 is similar in properties to nylon 6, but is superior in heat resistance to nylon 6 and superior in self-extinguishing and abrasion resistance. Nylon 6.6 is prepared by dehydration condensation polymerization of hexamethylenediamine and adipic acid.

(Scheme 2) Dehydration condensation of hexamethylenediamine with adipic acid Nylon 6.6 polymerization by polymerization

The polyhexamethylene adipamide polymer contains at least 85 mole percent hexamethylene adipamide repeat units, preferably only hexamethylene adipamide units.

Alternatively, optional polyamide homopolymers and copolymers may be used in place of polyhexamethylene adipamide. Such polyamides can be predominantly aliphatic. Poly (hexamethylene adipamide) (nylon 6.6); Poly (epsilon -caproamide) (nylon 6); And nylon 6.6 are most preferred, although widely used nylon polymers such as their copolymers can be used.

In order to improve the thermal stability during the production of the polyhexamethylene adipamide chip, the residual amount of the copper metal in the final polymer may be 20 to 50 ppm. If this amount is less than 20 ppm, the thermal stability is lowered during the spinning and pyrolysis occurs. If it exceeds 50 ppm, more than necessary copper metal acts as a foreign substance, which may be a problem in spinning. The polyhexamethylene adipamide chips prepared are made of fibers by the apparatus shown in Fig.

1, a polyhexamethylene adipamide chip is packaged through a pack 1 and a nozzle 2, preferably at a spinning temperature of 270 to 310 DEG C, preferably a radiation draft ratio of 20 to 200 The linear velocity on the roller / the linear velocity on the nozzle). This process is intended to prevent a decrease in the viscosity of the polymer due to thermal decomposition. If the spinning draft ratio is less than 20, the uniformity of the filament cross section may be deteriorated to deteriorate the drawability. If it exceeds 200, filament breakage may occur during spinning, thereby making it difficult to produce normal yarns.

The filtration residence time in the pack of chips in the melt spinning process should be adjusted to 3 to 30 seconds. If the filtration retention time in the pack is less than 3 seconds, the filtering effect of the foreign substance is insufficient, and if it exceeds 30 seconds, the excessive packing pressure may increase the pyrolysis. It is also preferred that the L / D (length / diameter) of the extruder screw in the melt spinning process is from 10 to 40. If the L / D of the screw is less than 10, uniform melting is difficult. If the screw has an L / D of more than 40, the molecular weight may be lowered due to excessive shear stress.

The produced melt discharge yarn 4 is quenched and solidified by passing through the cooling zone 3. The quenching and solidifying process is classified into an open quenching method, a circular closed quenching method and a radial outflow quenching method according to a method of blowing cooling air in the cooling zone 3, Of these methods, an open quenching method is preferred. Thereafter, the discharged yarn 4 which has passed through the cooling zone 3 and solidified is oiled to 0.5 to 1.0% by the emulsion applying device 5 and becomes unstretched.

The preferred spinning speed of the prepared non-drawn yarn is 200 to 1,000 m / min. The yarn passed through the first stretching roller 6 is stretched by a spin draw method while passing through a series of stretching rollers 7, 8, 9 and 10 so that the total yarn ratio is 4.0 times or more, preferably 4.5 to 6.5 To obtain the final drawn yarn 11.

It is advantageous that the value of the dry heat shrinkage (160 DEG C, 30 minutes) of the produced fiber is 3 to 6%. The low shrinkage ratio of such fibers can be obtained by stabilizing the crystal structure of the drawn yarn in the heat treatment step after the two-stage stretching process. The multi-stage drawing process in the fiber manufacturing process includes a primary drawing process which proceeds at a high drawing magnification at a low drawing temperature and a secondary drawing process which proceeds at a relatively low drawing magnification at a high temperature. In the primary drawing step, crystallization mainly proceeds by orientation. Crystallization by this orientation is a factor that determines the heat shrinkage of the cord. The preferred stretching temperature in the primary stretching step is 20 to 50 DEG C and the stretching ratio is 3.0 times or more. If an additional cooling device is not provided in the drawing roller in the process, it is difficult to control the drawing temperature to be less than 20 캜, which is economically disadvantageous. On the other hand, if the drawing temperature exceeds 50 캜, crystallization by heat may proceed. Further, if the draw ratio is less than 3.0 times, sufficient orientation crystallization hardly occurs.

Through the second elongation process, crystallization proceeds by heat at a high temperature. At these high temperatures, heat-induced crystals affect the heat shrinkage of the cord. In the secondary drawing step of the present invention, the drawing temperature is preferably 200 to 250 ° C and the drawing magnification is 2.0 times or less. When the drawing temperature is less than 200 ° C, sufficient crystallization does not proceed by heat. When the drawing temperature exceeds 250 ° C Causing damage to the product. Also, when the draw ratio exceeds 2.0 times, the elongation of the yarn decreases sharply. The relaxation temperature is adjusted to 200 to 250 ° C and the relaxation rate is adjusted to 3 to 7% in order to stabilize the crystal structure of the drawn yarn. The low shrinkage characteristics of such fibers can be prevented from rapidly shrinking in the treatment process for a tire cord, and thus they are represented by a high strength utilization ratio.

(2) a strength of 9.0 g / d or more; (3) an elongation of 10% or more; (4) a shrinkage of 10% or more; ) 500 to 3000 denier.

Hereinafter, a method for producing the aramid yarn used in the present invention will be described in detail with reference to the accompanying drawings.

The apparatus for producing an aramid fiber comprises a dope supply unit; Spinning detention; As a solidifying portion; Wherein the solidifying portion comprises: a coagulation bath located at a lower portion of the spinneret and containing a coagulating solution; A first coagulation tube positioned below the coagulation bath to provide a discharge passage for the coagulation liquid; An injection port attached to one side of the first coagulation tube at an angle of 20 to 40 degrees to inject a second coagulating solution; A second solidification tube attached to a lower end portion of the injection port; And the second solidification tube has a concavo-convex shape.

The dope containing the aromatic polyamide supplied from the dope supply portion is extruded through the spinneret and then solidified while passing through the solidifying portion to form the multifilament. The aromatic polyamide is a para-aramid having a high strength and a high modulus of elasticity, and is a polyparaphenylene terephthalamide (PPD-T), a poly (4,4'-benzanilide terephthalamide), a poly , 4'-biphenylene-dicarboxylic acid amide), poly (paraphenylene-2,6-naphthalene dicarboxylic acid amide), or a mixture of two or more thereof. The aromatic polyamide can be produced by the following method. First, an inorganic salt is added to an organic solvent to prepare a polymerization solvent. Examples of the organic solvent include N-methyl-2-pyrrolidone (NMP), N, N'-dimethylacetamide (DMAc), hexamethylphosphoramide (HMPA) Methyl urea (TMU), N, N-dimethylformamide (DMF) or mixtures thereof may be used. As the inorganic salt, CaCl2, LiCl, NaCl, KCl, LiBr, KBr, or a mixture thereof may be used. The inorganic salt is added in order to increase the polymerization degree of the aromatic polyamide. However, since the inorganic salt which is not dissolved when the inorganic salt is added in an excess amount may be present in the polymerization solvent, the content of the inorganic salt in the polymerization solvent is preferably 10% by weight or less. Since the solubility of the inorganic salt in the organic solvent is poor, water is added to completely dissolve the inorganic salt, and then the water is removed through a dehydration process, whereby a final polymerization solvent can be prepared.

Next, the aromatic diamine is dissolved in the polymerization solvent to prepare a mixed solution. The aromatic diamine may be para-phenylenediamine, 4,4'-diaminobiphenyl, 2,6-naphthalenediamine, 1,5-naphthalenediamine, or 4,4'-diaminobenzanilide. Then, a primary polymerization is carried out by adding a predetermined amount of aromatic diacid halide to the mixed solution while stirring the mixed solution. The aromatic diacid halide may be terephthaloyl dichloride, 4,4'-benzoyl dichloride, 2,6-naphthalene dicarboxylic acid dichloride, or 1,5-naphthalene dicarboxylic acid dichloride. Through the primary polymerization, a prepolymer is formed in the polymerization solvent. Subsequently, an aromatic diacid halide is further added to the above polymerization solvent to carry out a secondary polymerization, and through this secondary polymerization, an aromatic polyamide is finally obtained. The aromatic polyamide may be selected from the group consisting of polyparaphenylene terephthalamide (PPD-T), poly (4,4'-benzanilide terephthalamide), poly (paraphenylene- 4,4'-biphenylene-dicarboxylic acid amide), or poly (paraphenylene-2,6-naphthalene dicarboxylic acid amide).

Next, an alkaline compound such as NaOH, Li2CO3, CaCO3, LiH, CaH2, LiOH, Ca (OH) 2, Li2O, CaO or the like is added to the polymerization solution to neutralize the hydrochloric acid generated during the polymerization reaction. On the other hand, it may be advantageous to carry out the subsequent processes by adding water to the polymerization solution obtained through the primary and secondary polymerization processes to prepare a slurry state to improve its flowability. At this time, the neutralization step and the slurry production step may be performed simultaneously by adding water in which the alkali compound is dissolved to the polymerization solution.

Subsequently, the polymerization solvent is extracted from the polymerization solution. Such an extraction process is most effective and economical to perform using water. For example, a filter may be installed in a bath equipped with an outlet, and the polymer may be placed on the filter, and then water may be poured to discharge the polymerization solvent contained in the polymer together with water to the outlet. On the other hand, if the particle size of the aromatic polyamide present in the polymerization solution is too large, it takes a long time to extract the polymerization solvent and the productivity may be lowered. Therefore, the step of pulverizing the aromatic polyamide may be performed before the polymerization solvent extraction step.

Then, the water remaining in the aromatic polyamide is removed through dehydration and drying processes. The dope prepared by the above method is supplied to the spinneret through the dope supplying section and then extruded. The spinneret has a plurality of capillaries having a diameter of 0.1 mm or less. If the diameter of the capillary formed in the spinneret exceeds 0.1 mm, the molecular orientation of the resulting monofilament is deteriorated, resulting in a decrease in the strength of the multifilament. The concavo-convex shape is formed to promote the generation of turbulence, and the second coagulation tube has a cross-sectional area of 8 to 11 mm and a concavo-convex radius of 0.5 to 1.5 mm. The sum of the lengths of the first and second coagulation tubes is preferably 100 to 150 mm. If the sum of the lengths is less than 100 mm, the effect of irregularities is insufficient and uniform coagulation is not achieved. For example, if the length exceeds 150 mm, the pumping ability of the coagulation solution stored in the coagulation bath It can fall. The injection port is attached to one side of the first solidification tube, preferably at an angle of 20 to 40 degrees, preferably at an angle of 30 degrees. If it is attached outside the above-mentioned angle, that is, 20 to 40 degrees, the pumping ability to the coagulating solution becomes too slow, and high-speed spinning becomes impossible. The secondary coagulation solution injected through the injection port is manufactured so that the composition and temperature of the primary coagulation solution and the solvent are different. This is also intended to promote the generation of turbulence as in the case of the second coagulation tube of concavo-convex shape. The promotion of the generation of the turbulent flow can improve the extraction of the residual solvent, particularly sulfuric acid, and prevent the deterioration of the properties of the finally produced aramid fiber.

The properties of the aramid fiber may include elongation and tensile strength. Needless to say, however, the present invention is not limited thereto and includes all physical properties that can be measured by a person skilled in the art.

The hybrid dipped cord according to the present invention is obtained by dipping one raw nylon 6.6 or nylon 6 yarn and one aramid yarn into a dipping solution and then heat-treating the raw cord so that the length of nylon 6.6 or nylon 6 yarn Wherein the aramid yarn is thermally shrunk so as to be shorter than the aramid yarn, and the aramid yarn is 5 to 100 mm / m longer than the nylon 6.6 yarn or the nylon yarn 6 when the thus prepared dip cord is formed.

In the production of hybrid cords using nylon 6.6 or nylon 6 and aramid yarns manufactured. And a step of giving a cord to the cord as a pre-stage of dip code production (a twisting process).

The nylon 6.6 yarn or the nylon yarn 6 produced by the above method and the aramid yarn manufactured by the above method can be obtained by twisting one yarn of each wound yarn with a direct twisted yarn in which both the twisted yarns and the twin yarns are simultaneously wound, Raw code '. The raw cord is manufactured by applying a ply twist to a nylon 6.6 yarn for a tire cord or a nylon 6 yarn and an aramid yarn, and then applying a cable twist to the aramid yarn. In general, the same yarn is applied to the upper and lower yarns.

Generally, when the twist is high, the strength decreases, and the midline and the twist tend to increase. My fatigue also shows a tendency to improve with increasing kinks. The hybrid tire cord manufactured according to the present invention was manufactured at 200 to 500 TPM (twist per meter) at the same time. At this time, when the temperature is less than 200/200 TPM, the loss of the cord is reduced and the fatigue resistance tends to be lowered. When the pressure is higher than 500 TPM, the strength drop is large and is not suitable for tire cords.

The fineness of nylon 6.6 or nylon 6 yarn and aramid yarn used in twisting yarns is preferably 500 to 3000 denier. Below 500 denier, the strength drop is very large at 500 TPM and above 3000 denier is not preferred because the fatigue is reduced at 200 TPM.

The manufactured 'Raw Cord' is woven using a weaving machine, and the obtained fabric is immersed and cured in the dipping solution to form a 'cord' Dip cord ".

The dipping process of the present invention will be described in more detail. Dipping is accomplished by impregnating the surface of the fiber with a resin layer called RFL (Resorcinol Formalin-Latex). The disadvantage of the fiber for tire cords, .

In the case of using polyethylene terephthalate or polyethylene naphthalate fiber, the surface of the polyethylene terephthalate is first exposed to the surface of the fiber because the reactor on the surface of the fiber is smaller than that of the rayon fiber or the nylon fiber After activation, the adhesive treatment is performed (2 bath dipping).

In the present invention, an adhesive liquid for bonding a hybrid cord and rubber can be manufactured by the following method. It is to be understood that the following examples are intended only for a better understanding of the present invention and are not intended to limit the scope of the present invention.

29.4 wt% resorcinol 45.6 parts by weight; 255.5 parts by weight of distilled water; 37% formalin 20 parts by weight; And 3.8 parts by weight of 10 wt% sodium hydroxide were prepared and reacted at 25 DEG C for 5 hours with stirring. Next, 300 parts by weight of 40% by weight of VP-latex, 129 parts by weight of distilled water and 23.8 parts by weight of 28% ammonia water were added and aged at 25 DEG C for 20 hours to maintain a solid concentration of 19.05%.

A stretch of 0 to 3% is required to adjust the adhesion amount of the adhesive liquid, and preferably 1 to 2% of the elongation can be achieved. If the elongation percentage is too high, the adhesion amount of the adhesive liquid can be adjusted but the yield is reduced and the fatigue resistance is reduced as a result. On the other hand, if the elongation percentage is too low, for example, if it is lowered to less than 0%, there is a problem that it is impossible to control the DPU by penetrating the dipping solution into the cord.

The adhesion amount of the adhesive is preferably 2 to 7% based on the weight of the fibers on a solid basis. After passing through the adhesive solution, the hybrid dip cords are dried at 120-180 占 폚. Dried for 180 seconds to 220 seconds, and dried in a state where the hybrid dipped cord is stretched to about 1 to 2% in the drying process. If the elongation ratio is low, the cords and the cord of the cord increase, which may result in a property that is difficult to apply to the tire cord. On the other hand, if the elongation ratio is more than 3%, the level of the medium is adequate but the turnover may be too small to reduce the fatigue resistance.

After drying, heat treatment is performed at a temperature range of 130 to 260 ° C. The elongation ratio during the heat treatment is maintained between -2 and 3%, and the heat treatment time is suitably between 50 and 90 seconds. If the heat treatment is performed for less than 50 seconds, the reaction time of the adhesive solution is insufficient and the adhesive force is lowered. If the heat treatment is performed for more than 90 seconds, the hardness of the adhesive solution becomes high and the fatigue resistance of the cord may be decreased have.

In order to further shrink the nylon 6.6 yarn or the nylon 6 yarn in the heat treatment step, one or more methods selected from the group consisting of a method of adjusting tension applied to the raw cord, a method of adjusting the heat treatment temperature, and a method of adjusting the heat treatment time Respectively.

The tension was controlled through the speed of the feed roller and the winding roller, the heat treatment temperature was 130 to 240 占 폚, and the heat treatment time was 50 to 90 seconds.

With respect to this heat treatment process, when the twist number of aramid yarn and nylon 6.6 or nylon 6 yarn is kept the same in the twisting step and the nylon 6.6 or nylon 6 yarn is shrunk when the raw cord is subjected to the heat treatment process, (Seaweed) Nylon 6.6 per unit length or aramid yarn is longer than six nylon yarns. As long as nylon 6.6 or nylon 6 shrinks and aramid yarn becomes longer, the initial strain is generated by nylon 6.6 or nylon 6 yarn during the tensile test, and then the deformation is caused by the aramid yarn.

The length difference caused by the shrinkage of the nylon 6.6 or nylon 6 yarn is effective when the length difference of each yarn is about 5 to 100 mm / m when the dipped cord is loosened, and it is effective that the aramid yarn is preferably long. If the difference is less than 5mm, the fatigue is reduced and it is not suitable. If the difference exceeds 100mm, the strength is decreased and it is not appropriate. According to one embodiment of the present invention, it is most preferable that the difference is 10 to 30 mm / m.

In the manufacturing method according to the present invention, the aramid yarn tends to have a lower strength and a higher mid / longer yarn strength as compared with nylon 6.6 or nylon 6 yarn, and the increase in fatigue due to the increase in aramid yarn length can be expected. The longer the length of nylon 6, but the shorter the length of aramid yarn), the higher the strength, the lower the mid / turn and fatigue. Especially in this case, the initial strain in tension test causes low modulus by nylon 6.6 or nylon 6 and high modulus is expressed from the section where aramid begins to receive force.

The hybrid dipped cord produced according to the above-described method is characterized by having an internal fatigue of 85% or more. If the fatigue strength is less than 85%, the durability of the tire is reduced.

The hybrid dipped cord manufactured through such a process is used for the manufacture of tires for passenger cars. When the aramid yarn is used solely for blasting the green tire inside the mold during vulcanization, Deformation can be easily performed as compared with the case where there is a difficulty in deformation, so that it is used for easy manufacture of a tire. The hybrid dipped cord manufactured through such a process is applied to tires for passenger cars. It is mainly applied to cap ply and carcass ply to improve low fatigue resistance and adhesion, which is a problem when aramid yarn is used alone, and nylon 6.6 It is used to manufacture high performance tires with excellent fatigue resistance by improving low modulus and heat resistance which are problematic when using nylon 6 alone.

Fig. 3 shows the structure of a tire for a passenger car in which the hybrid dipped cord according to the present invention is applied as a carcass ply or a cap ply.

Referring to Fig. 3, the bead region 35 of the tire 31 becomes an annular bead core 36 that is non-stretchable. The bead core 36 is preferably made of a single or single filament wire wound continuously. In a preferred embodiment, a high strength steel wire having a diameter of 0.95 mm to 1.00 mm forms a 4x4 structure and a 4x5 structure.

In an embodiment of the tire cord according to the present invention the bead region 35 may have a bead filler 37 and the bead filler 37 should have a hardness above a certain level and preferably a Shore A hardness 40 Or more.

According to the present invention, the tire 31 can be reinforced by the belt 38 and the cap ply 39. The belt 38 comprises a cut belt ply 40 consisting of two cords 41 and 42 and the cord 41 of the belt ply 40 is oriented at an angle of about 20 degrees with respect to the circumferential center plane of the tire. . One cord 41 of the belt ply 40 may be disposed opposite the direction of the cord 42 of the other belt ply 40 in a direction opposite the circumferential center plane. However, the belt 38 may comprise any number of plys, and may preferably be located in the range of 16 to 24 degrees. The belt 38 serves to provide lateral stiffness to minimize the rise of the tread 33 from the road surface during operation of the tire 31. The cords 41 and 42 of the belt 38 may be made of steel cords and have a 2 + 2 structure, but may be made of any structure. The cap ply 39 and the edge ply 44 are reinforced on the upper portion of the belt 38 so that the cord 45 of the cap ply 39 is reinforced in parallel with the circumferential direction of the tire, And the cord 45 of the cap ply 39 having a large heat-shrinking stress at a high temperature is used. One layer of cap ply 39 and one layer of edge ply 44 may be used, and preferably one or two layers of cap ply and one or two layers of edge ply may be reinforced.

3, reference numerals 32 and 34 denote a carcass layer 32 and a fly turn 34. And reference numeral 33 denotes a carcass layer reinforcing cord 33. [

Embodiments and comparative examples which do not limit the scope of the present invention are described below. In the following Examples and Comparative Examples, the properties of the hybrid dip cords were evaluated by the following methods.

(a) Hybrid dip cord strength (kgf) and moderate elongation (%)

Dried at 107 DEG C for 2 hours, and then measured at a sample length of 250 mm and a tensile speed of 300 m / min using a low-speed stretching type tester manufactured by Instron. The elongation at specific load was measured at a load of 4.5 kg.

(b) Dry Heat Shrinkage (%, Shrinkage)

The ratio of the length (L0) measured at a constant load of 0.05 g / d and the length (L1) after treatment at a constant load of 0.05 g / d for 30 minutes at 150 ° C To show dry heat shrinkage ratio.

S (%) = (L0 - L1) / L0 100

(c) hybrid dip code E-S value

The term "elongation under a constant load" is referred to as "elongation (E)" in the present invention. "S" means the dry heat shrinkage rate in the above (b), and the sum of the elongation at break (E) Respectively.

E-S = moderate elongation (%) + dry heat shrinkage (%)

(d) My fatigue

The residual fatigue strength was measured by using a Belt Fatigue Tester, which is commonly used for fatigue test of tire cords, and fatigue resistance was compared. The fatigue test conditions were normal temperature, load of 80 kg, and repeated 37,500 times. After the fatigue test, the rubber and cord were separated and the residual strength was measured. The residual strength was measured according to the above method (a) using a normal tensile strength tester.

[Example 1]

Nylon 6.6 and aramid fibers were obtained in the same manner as described above to produce tire reinforcing fibers. One knot of nylon 6.6 yarn (1260D) and one yarn of aramid yarn (1500D) were each twisted at 400 TPM, and the yarn was folded to give a twist of 400 TPM. And then passed through an adhesive liquid prepared by the following method to give an adhesive liquid.

29.4 wt% resorcinol 45.6 parts by weight; 255.5 parts by weight of distilled water; 37% formalin 20 parts by weight; And 3.8 parts by weight of 10 wt% sodium hydroxide were prepared and reacted with stirring at 25 DEG C for 5 hours and the following components were added:

300 parts by weight of 40 wt% VP-latex, 129 parts by weight of distilled water, 28% ammonia water, 23.8 parts by weight After the components were added, they were aged at 25 캜 for 20 hours to maintain a solid content concentration of 19.05%.

After the adhesive solution was applied and dried at 150 ° C for 2 minutes, heat treatment was performed while stretching at 240 ° C for 60 seconds to shrink the nylon 6.6 yarn, and the aramid yarn was further lengthened by 10 mm / m to finish the adhesive treatment. The physical properties of the thus-prepared hybrid dip cords were evaluated and are shown in Table 1.

[Example 2]

A raw cord and a deep cord were prepared in the same manner as in Example 1, except that aramid yarn was longer by 20 mm / m when it was heat-treated for 90 seconds and then melted. The properties of the thus-prepared dip cords were evaluated and are shown in Table 1.

[Example 3]

A raw cord and a deep cord were prepared in the same manner as in Example 1, except that nylon 6.6 yarn (840D) and aramid yarn (1000D) were used. The properties of the thus-prepared dip cords were evaluated and are shown in Table 1.

[Example 4]

The raw cord and dip cord were produced in the same manner as in Example 1 except that nylon 6.6 yarn (840D) and aramid yarn (1000D) were used and the aramid yarn was longer by 20 mm / m when the yarn was heat treated for 90 seconds Respectively. The properties of the thus-prepared dip cords were evaluated and are shown in Table 1.

[Comparative Example 1]

The raw cord and the deep cord were prepared in the same manner as in Example 1, except that aramid yarn was inserted 10 mm / m longer at the time of lamination. The properties of the thus-prepared dip cords were evaluated and are shown in Table 1.

[Comparative Example 2]

A raw cord and a deep cord were prepared in the same manner as in Example 1, except that nylon 6.6 yarn was inserted 15 mm / m longer when the yarn was folded. The properties of the thus-prepared dip cords were evaluated and are shown in Table 1.

[Comparative Example 3]

The raw cord and the dip cord were prepared in the same manner as in Example 1, except that nylon 6.6 yarn was added at a distance of 20 mm / m to the yarn. The properties of the thus-prepared dip cords were evaluated and are shown in Table 1.

[Comparative Example 4]

A raw cord and a deep cord were prepared in the same manner as in Example 1, except that nylon 6.6 yarn was inserted 25 mm / m longer at the time of yarn winding. The properties of the thus-prepared dip cords were evaluated and are shown in Table 1.

[Comparative Example 5]

A raw cord and a deep cord were prepared in the same manner as in Example 1, except that nylon 6.6 yarn was inserted 30 mm / m longer when the yarn was folded. The properties of the thus-prepared dip cords were evaluated and are shown in Table 1.

division Processing Code Properties Remarks strong
(kg) Intermediate stretch
6.8kg (%) Shrinkage rate
(%) ES value
(%) My Fatigue
(%) Adhesion
(kg) Example 1 37.2 5.0 1.7 6.7 86.3 18.6 Example 2 37.0 5.5 1.5 7.0 89.2 19.2 Example 3 24.7 5.1 1.4 6.5 87.8 19.9 Example 4 24.3 5.6 1.2 6.8 85.9 18.8 Comparative Example 1 37.1 5.2 1.6 6.8 83.4 18.3 High ES value, low fatigue Comparative Example 2 36.8 5.4 1.5 6.9 83.2 18.2 High ES value, low fatigue Comparative Example 3 36.9 5.6 1.4 7.0 83.8 17.9 High ES value, low fatigue Comparative Example 4 36.5 5.8 1.3 7.1 82.9 18.0 High ES value, low fatigue Comparative Example 5 36.7 6.0 1.2 7.2 83.0 18.5 High ES value, low fatigue

In the case of the hybrid dipped cord according to the present invention (Examples 1, 2, 3 and 4), the length difference between the nylon 6.6 yarn and the aramid yarn It can be seen that the fatigue resistance is improved as compared with the hybrid dipped cord (Comparative Example 1) which does not suffer from cracking.

In addition, hybrid dipped cords (Comparative Examples 2, 3, 4, and 5) in which nylon 6.6 yarns were inserted for a longer time are superior in strength to hybrid dipped cords according to the present invention, but have low fatigue resistance.

[Example 5]

A radial tire manufactured using the hybrid dipped cord manufactured by Example 1 of the present invention as a cap ply has a carcass layer having a radially outer side fly-turn, and the carcass layer is provided so as to include one layer. At this time, the specifications of the carcass cords were as shown in the following Table 3 and aligned at an angle of 90 degrees with respect to the circumferential intermediate surface of the tire. The fly-turn 34 has a height of 40 to 80% with respect to the maximum cross-sectional height of the tire. The bead portion 35 has a bead core 36 having a high strength steel wire 4 having a diameter of 0.95 to 1.00 mm and a bead filler 37 having a hardness of 40 or more and a shore A hardness of 40 or more. The belt 38 is reinforced by a belt reinforcing layer consisting of one layer of cap ply 39 and one layer of edge ply 44 at the top so that the cap ply cords in the cap ply 39 are parallel to the circumferential direction of the tire Respectively.

[Example 6]

A tire was prepared in the same manner as in Example 5, except that the cord material for tire fabrication was the hybrid dipped cord prepared in Example 2. [

[Example 7]

A tire was produced in the same manner as in Example 5, except that the cord material for tire fabrication was the hybrid dipped cord prepared in Example 3.

[Example 8]

A tire was produced in the same manner as in Example 5, except that the cord material for tire fabrication was the hybrid dipped cord prepared in Example 4.

[Comparative Example 6]

Tires were prepared in the same manner as in Example 5, except that the cord material for tire fabrication was a hybrid dip cord manufactured by Comparative Example 1.

Example 5 Example 6 Example 7 Example 8 Comparative Example 6 Kakas Material PET PET PET PET PET Specification (d / summing speaker) 1500d / 2 1500d / 2 1500d / 2 1500d / 2 1500d / 2 Power (kg) 24 24 24 24 24 Modulus of elasticity (g / d) 60 60 60 60 60 Cap fly Material The hybrid dip code of Example 1 The hybrid dip code of Example 2 The hybrid dip code of Example 3 The hybrid dip code of Example 4 The hybrid dip code of Comparative Example 1 tire Flat rate 0.60 0.60 0.60 0.60 0.60 Number of carcass layers One One One One One Cap fly layer number One One One One One

[Example 9]

A radial tire manufactured using the hybrid dip code manufactured by Example 1 of the present invention has a carcass layer having a radially outer side fly-turn, and the carcass layer is provided so as to include one layer. The specifications of the cap ply and carcass cord were as shown in the following Table 3, and tires were produced in the same manner as in Example 5.

[Example 10]

A tire was prepared in the same manner as in Example 5, except that the cord material for tire fabrication was the hybrid dipped cord prepared in Example 2. [

[Example 11]

A tire was produced in the same manner as in Example 5, except that the cord material for tire fabrication was the hybrid dipped cord prepared in Example 3.

[Example 12]

A tire was produced in the same manner as in Example 5, except that the cord material for tire fabrication was the hybrid dipped cord prepared in Example 4.

[Comparative Example 7]

Tires were prepared in the same manner as in Example 5, except that the cord material for tire fabrication was a hybrid dip cord manufactured by Comparative Example 1.

Example 9 Example 10 Example 11 Example 12 Comparative Example 7 Kakas Material The hybrid dip code of Example 1 The hybrid dip code of Example 2 The hybrid dip code of Example 3 The hybrid dip code of Example 4 The hybrid dip code of Comparative Example 1 Cap fly Material Nylon 6.6 Nylon 6.6 Nylon 6.6 Nylon 6.6 Nylon 6.6 Specification (d / summing speaker) 1260D / 2P 1260D / 2P 1260D / 2P 1260D / 2P 1260D / 2P Power (kg) 22.4 22.4 22.4 22.4 22.4 tire Flat rate 0.60 0.60 0.60 0.60 0.60 Number of carcass layers 2 2 2 2 2 Cap fly layer number One One One One One

The 205/65 R15 V tire manufactured in accordance with Examples 5, 6, 7, 8, 9, 10, 11, 12 and Comparative Examples 6 and 7 was mounted on a 2000cc class passenger car and driven at a speed of 60 km / (DB) in the audible frequency range by measuring the noise generated in the vehicle. The steered driver rides the test course and evaluates the driving stability and riding comfort in five points on the scale of 100 points. The results are shown in Table 4 below. The durability was measured in accordance with the P-metric tire endurance test of FMVSS 109 at a temperature of 38 ° C (Celsius), 85, 90 and 100% of the rated tire load, at a running speed of 80 km / h And it was judged as OK (OK) when no traces such as bead separation, cord cutting, belt separation were found in any part such as tread, sidewall, carcass cord, inner liner and bead.

division Tire weight
(kg) Ride comfort Steering stability durability Uniformity Noise (dB) Example 5 9.54 100 100 OK 100 61.2 Example 6 9.70 100 100 OK 100 61.4 Example 7 9.55 100 100 OK 100 61.4 Example 8 9.69 100 100 OK 100 61.3 Comparative Example 6 9.60 96 95 OK 96 63.5 Example 9 9.64 100 100 OK 100 60.4 Example 10 9.70 100 100 OK 100 61.0 Example 11 9.63 100 100 OK 100 60.3 Example 12 9.71 100 100 OK 100 61.1 Comparative Example 7 9.60 93 94 OK 92 64.3

As a result of the test of Table 4, when using the hybrid cord according to the present invention (Examples 5, 6, 7, and 8), nylon 6.6 yarn and 6.6 yarn were inserted into the cap fly, It can be seen that the effect of noise reduction and steering stability is better than that of Comparative Example 6 using a hybrid dipped cord having no difference in length, and that the unity of the tire is also improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the above teachings. will be.

31: Tire 32: Carcass layer
33: Carcass layer reinforcement cord 34: Fly turn-up
35: bead region 36: bead core
37: bead filler 38: belt structure
39: cap fly 40: belt fly
41, 42: belt cord 43: tread
44: edge fly 45: cap fly cord

Claims (13)

In hybrid dipped cords for radial pneumatic tires,
One raw nylon 6.6 yarn or nylon 6 yarn and one aramid yarn, each of which is made up of a raw cord; And
The raw cord is dipped in a dipping solution and then heat-treated to heat-shrink the nylon 6.6 yarn or the nylon 6 yarn so that the length of the yarn is shorter than that of the aramid yarn.
When the deep cords are finished, the aramid yarns are 10 to 30 mm / m long compared to nylon 6.6 yarns or nylon 6 yarns,
(Intermediate elongation + dry heat shrinkage) value of 6.5 to 7.0%, adhesion of 18.6 to 19.9 kg, and fatigue of 85.9 to 89.2%, respectively, with a strength of 24.3 to 37.2 kg, an intermediate elongation of 5.0 to 5.6%, a shrinkage of 1.2 to 1.7% % ≪ / RTI > The method according to claim 1,
Heat-shrinking the nylon 6.6 or nylon 6 yarn so that the length of the nylon 6.6 yarn or the nylon 6 yarn is shorter than that of the aramid yarn may be achieved by a method of adjusting the tension applied to the raw cord, a method of adjusting the heat treatment temperature, Hybrid dip code < RTI ID = 0.0 > delete delete delete A method of manufacturing a hybrid dipped cord for a radial pneumatic tire,
One yarn of nylon 6.6 yarn or nylon yarn 6 and one yarn of aramid yarn, respectively, to give a twist of 200 to 500 TPM yarns;
Folding the twisted yarn in two, and twisting the twisted yarn in a number of 200 to 500 TPM to produce a cord; And
Dipping the raw cord in a dipping solution and then heat treating the nylon 6.6 yarn or nylon 6 yarn so that the length of the nylon 6.6 yarn is shorter than that of the aramid yarn,
When the deep cords are formed, aramid yarns are 10 to 30 mm / m long compared to nylon 6.6 yarns or nylon 6 yarns,
The dip cord had a strength of 24.3 to 37.2 kg, an intermediate elongation of 5.0 to 5.6%, a shrinkage of 1.2 to 1.7%, an ES (modulus of elongation + dry heat shrinkage) of 6.5 to 7.0%, an adhesive strength of 18.6 to 19.9 kg, Is 85.9 to 89.2%. ≪ RTI ID = 0.0 > The method according to claim 6,
In order to further shrink the nylon 6.6 yarn or the nylon 6 yarn in the heat shrinking step, one or more methods selected from the group consisting of a method of controlling the tension applied to the raw cord, a method of adjusting the heat treatment temperature, and a method of controlling the heat treatment time A method for producing a hybrid dipped cord 8. The method of claim 7,
Wherein the tensile force is adjusted through the speed of the feed roller and the take-up roller, the heat treatment temperature is 130 to 240 ° C, and the heat treatment time is 50 to 90 seconds. delete delete The method according to claim 6,
Wherein the fineness of the nylon 6.6 yarn or the nylon 6 yarn and the aramid yarn are respectively 500 to 3000 denier A pair of parallel bead cores and at least one radial carcass layer wound around the bead cores, a belt layer laminated on the outer circumferential side of the carcass layer, and a radial air layer including a circumferential belt reinforcing layer formed on the outer circumferential side of the belt layer In the mouth tires,
Characterized in that the carcass layer comprises the hybrid dipped cord according to claims 1 or 2 and the carcass layer is used as one or two layers. A pair of parallel bead cores and at least one radial carcass layer wound around the bead cores, a belt layer laminated on the outer circumferential side of the carcass layer, and a radial air layer including a circumferential belt reinforcing layer formed on the outer circumferential side of the belt layer In the mouth tires,
Wherein the cap ply as the belt reinforcing layer comprises the hybrid dipped cord according to claim 1 or 2, wherein the cap ply is used as one or two layers.

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