KR101922774B1 - Mdehtod of manufacturing filler for tyre inner liner and tyre containing the same - Google Patents

Abstract

The present invention discloses a method for manufacturing a tire innerliner filler composition and a composition thereof.
A method for manufacturing a tire inner liner filler composition according to the present invention comprises steps S1) of stirring the inorganic filler and asphalt at a temperature of 150 to 250 ° C to secure homogeneity to the initial viscosity, A step S2 of adding the coal ash and stirring the mixture to a final viscosity, and a step S3 in which the mixture is compacted at a final viscosity and molded into a plate. In this case, the flat inner liner It is possible to improve the permeability of the gas or the liquid of the inner liner and to increase the bonding force with the viscoelastic material having reactivity, thereby preventing the inner liner from deteriorating.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of manufacturing a tire innerliner filler composition and a tire containing the composition,

TECHNICAL FIELD The present invention relates to a method of manufacturing a tire inner liner filler composition and a tire including the composition, and more particularly, to a tire inner liner filler composition which improves the gas impermeability of a tire inner liner, A method for manufacturing a tire inner liner filler composition which increases bonding force with an elastic body to prevent deterioration of inner liner properties, and a tire including the composition.

The Inner Liner of the tire is located at the innermost position in the structure of the tire, so that it does not leak air from the tire and the rim when it is attached to the car, and maintains the air pressure in the tire.

Accordingly, the air permeability of the rubber composition for a tire innerliner is required, and since the inner liner portion is subjected to the load of the vehicle or repeated fatigue due to the nature of the inner liner portion, endurance and crack resistance are required.

In recent years, there has been a demand for improvement in regeneration of inner liners as the demand for improvement in regeneration of tires has increased. In order to regenerate the tire, a high modulus showing durability is favorable, but when the modulus is increased, There is a problem to be done.

In order to obtain such moderate level of modulus, a method of controlling the amount of oil or resin during the production of the rubber composition for inner liner has been used.

However, when the additive is varied, the air permeability may be lowered. If the air permeability is reduced, the air pressure inside the tire is hardly maintained and durability is deteriorated. If the tensile property is too low, fatigue resistance may be advantageous. However, since the gauge is reduced by repetitive fatigue, There is a problem in that the cords are exposed and the fatigue characteristics such as high strain, winter season and aging are very weak.

In order to solve this problem, in Korean Patent Laid-Open Publication No. 2016-31159, 40 to 60 parts by weight of carbon black, 15 to 35 parts by weight of a sheet-like inorganic filler, and 3 to 7 parts by weight of hindered phenol, By weight of the rubber composition for a tire innerliner has been disclosed and its solution has been proposed, however, the permeability is still unsatisfactory and the physical properties of the innerliner are lowered.

Therefore, the first technical problem to be solved by the present invention is to provide a tie-hard filler which can improve the permeability of a gas or liquid of a tire inner liner and increase the bonding strength with a viscoelastic material having reactivity, And a method for manufacturing the inner liner filler composition.

Therefore, a second technical problem to be solved by the present invention is to provide a tie hardening filler for a tire, which improves the permeability of gas or liquid of a tire inner liner and increases the bonding strength with a viscoelastic material having reactivity, And a tire containing the inner liner filler composition.

In order to solve the above-mentioned first technical problem, the present invention provides a method for manufacturing an asphalt pellet, comprising the steps of: S1 step of stirring the inorganic filler and asphalt at 150 to 250 degrees to secure homogeneity to a starting viscosity; A step S2 of stirring the mixture to a final viscosity, and a step S3 of compacting the mixture at a final viscosity and molding the mixture into a plate-like body. The present invention also provides a method for manufacturing a tire innerliner filler composition.

According to an embodiment of the present invention, the step S2 further includes adding an aramid short fiber, and the aramid short fiber may have a diameter of 0.1 to 2 탆.

According to another embodiment of the present invention, the step S2 may further include the step of increasing the end viscosity by further adding carbon black.

According to another aspect of the present invention, there is provided a tire comprising a tire inner liner filler composition produced by the above-described manufacturing method.

Therefore, according to the present invention, it is possible to improve the permeability of a gas or a liquid of a tire innerliner with a plate-like hardener filler, and to increase the bonding force with a viscoelastic material having reactivity, thereby preventing deterioration of the properties of the innerliner.

Hereinafter, the present invention will be described in detail.

It is noted that the technical terms used in the present invention are used only to describe specific embodiments and are not intended to limit the present invention.

In addition, the technical terms used in the present invention should be construed in a sense generally understood by a person having ordinary skill in the art to which the present invention belongs, unless otherwise defined in the present invention, Should not be construed to mean, or be interpreted in an excessively reduced sense.

In addition, when a technical term used in the present invention is an erroneous technical term that does not accurately express the concept of the present invention, it should be understood that technical terms that can be understood by a person skilled in the art are replaced with a technical term. And should not be construed as being excessively reduced in meaning, and the singular expressions used in the present invention include plural expressions unless the context clearly dictates otherwise. ≪ RTI ID = 0.0 > In the present invention, the terms such as "comprising" or "comprising" and the like should not be construed as encompassing various elements or various steps described in the invention, May not be included, or may include additional components or steps Should be interpreted as possible.

The method of manufacturing a plate-like filler for tire rubber according to the present invention includes a step S1 of stirring an inorganic filler and asphalt at a temperature of 150 to 250 degrees to secure homogeneity and raising the initial viscosity to a starting viscosity, And then stirring the mixture to a final viscosity until the final viscosity is reached, and pressing the mixture at a final viscosity to form a platelike body.

First, in step S1, the inorganic filler and the asphalt are stirred at 150 to 250 degrees to ensure uniformity to thereby increase the initial viscosity. In order to uniformly mix the inorganic filler and the asphalt, the asphalt is preferably emulsified asphalt And mixed with an emulsifying agent to have a viscosity of 90 to 110 MU at a reference temperature of 100 ° C.

Here, the MU 10 as a viscosity ^- and ³ Ns / m ^2, N is the Newton, s is seconds, m is meter.

The average particle size of the asphalt can be controlled to 1 to 5 탆 to ensure compatibility with an average particle size of 2 탆 of the inorganic filler. As the inorganic filler, SiO ₂ , CaCO ₃ , Al ₂ O _3, or Fe ₂ O ₃ Can be used.

The asphalt and the inorganic filler are agitated at 150 to 250 ° C. If it is less than 150 ° C, the ester group is not only generated in the emulsified asphalt but also the reaction with the inorganic filler functional group may be difficult to occur. The subsequent process may be difficult because the paraffin oil may undergo denaturation or the reaction with the aramid short fiber may occur rapidly.

Next, step S2 is a step of adding the process oil and coal ash to the initial viscosity and then agitating the mixture to a final viscosity, wherein the initial viscosity is such that the viscosity of the asphalt and the inorganic filler in the step S1 is 90 - Means 135 to 165 MU, which is a 150% increase from 110 MU.

This is understood to be the formation of a group of asphalt particles having a high viscosity by setting water in the emulsified asphalt, and then the radical of the unsaturated asphalt is generated and a chemical reaction proceeds between the asphalt, the coal ash and the inorganic filler .

In addition, a process oil may be added to increase the mixing dispersibility and maintain the temperature.

It is advantageous to use paraffin oil as the process oil because it is excellent in compatibility with butyl rubber when applied to a rubber mixture compound of a tire inner liner.

Further, the aramid short fibers may be further added and maintained at 200 ° C at 20 RPM for 5 to 10 minutes. The aramid short fibers are fibers made of synthetic aromatic polyamide, and the length of the aramid short fibers May be in the range of from 5 탆 to 50 탆. If it is less than 5 탆, the reinforcing effect of the fibers may be insufficient and the plate shape may not be easily maintained. Conversely, if the thickness exceeds 50 탆, The endothelial characteristic and the exothermic characteristic can be remarkably lowered.

In addition, the diameter of the aramid short fibers may be 0.1 to 2 占 퐉. If the aramid short fibers are less than the lower limit, the endothelial property and cold resistance may decrease due to an increase in the high deformation tensile property in the rubber blend. On the other hand, The physical adhesion area with the matrix of the fiber is decreased and the reinforcing property is lowered, making it difficult to produce the sheet in the form of a plate.

Then, to increase the viscosity, carbon black is added, and the reaction can be stopped when the viscosity reaches about three times the viscosity at the start of the initial blending.

After the reaction is stopped, the viscosity tends to decrease by itself. If the reaction is continued even after the viscosity is increased by 3 times or more, the effect of the airtightness filler may be reduced because the radical bond is lost due to radical formation.

Next, the step S3 is a step of pressing the mixture to a high pressure at a final viscosity and molding the mixture into a plate. After the reaction is stopped, the mixture is uniformly milled to be dried and pressed. For example, The mixture is uniformly milled in a 1 cm mold, allowed to stand at room temperature for one day, pressed at a high pressure of 100 bar or more to form a plate having a specific gravity of 1.3 to 1.7 g / m ³ , The thickness is about 1 to 5 mu m.

If it is less than 1.3 g / m ³ , the specific gravity and shape of the plate may not be uniform. If it exceeds 1.7 g / m ³ , the hardness of the plate sharply increases sharply, And thus it is not preferable.

Such a plate may be crushed in the rubber compounding process to be mixed with fine particles, but it is of course possible to pulverize the crushed product by a crushing method such as milling for the uniformity of the particle size.

Further, in order to secure the degree of curing, it is possible to further cure the airtightness filler filler which has improved fatigue characteristics and resistance against deformation by further reacting the asphalt with ultraviolet rays.

It goes without saying that the plate material may be added to the inner liner compound so as to be molded into a semi-finished tire inner liner and applied to the tire as an inner liner layer.

Example

An inorganic filler mixed with SiO ₂ , Al ₂ O ₃ , CaCO ₃ and Fe ₂ O ₃ in an amount of 1: 5 by weight was added to emulsified asphalt having an average particle size of 2 μm and an initial viscosity of 100 MU (Mooney Sample) (Torque of ML (1 + 2.5)) was measured 2.5 minutes after preheating for 1 minute by operating S-type (Small rotor, diameter 30.5 mm, thickness 5.5 mm) motor at 2 rpm . Subsequently, a mixture of the mixture of the asphalt and the inorganic filler and a mixture of the added paraffin process oil, coal ash, and aramid short fibers (average diameter of 0.5 mu m, average length of 20 mu m) was mixed at a weight ratio of 1: Respectively. Carbon black (average particle size of 0.22 to 0.6㎛) is added slowly to the viscosity reached the 300MU by carbon black compression and crushing the mixed mixture at a pressure of 125bar density of 1.5g / m ³ and the average diameter of the longitudinal direction of plate material 3㎛ Tire inner liner filler composition was prepared.

Comparative Example

As a comparative example of the prior art, carbon black having a particle size of 140 nm or more, DBP 100 or less, and specific surface area (N2SA) of 40 or less was weakly developed in the tire inner liner was used in Comparative Example 1 and Comparative Examples 2 and 3 Used a calcium carbonate (CaCO ₃ ) single inorganic filler having an average particle size of 14 and 7 μm, which is conventionally used for improving the air permeability of the inner liner portion.

Experimental Example

To evaluate the efficiency of the filler prepared in the Examples and Comparative Examples, the tire innerliner compound was evaluated as shown in Table 1.

division Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Natural rubber (phr) 100 100 100 100 Carbon black (phr) 65 65 65 65 CaCO ₃ (phr) 20 20 Air tightness filler (phr) 10 Average particle size (um) 0.5 14 7 3 shape Aggregate Random, near-spherical three-dimensional Random, near-spherical three-dimensional Plate HD's 55 57 57 56 300% Modulus 40 37 36 39 T.S 85 75 74 70 E.B. 700 664 682 702 Permeability coefficient 127 118 122 109 Improvement rate (Index) 100 108 104 117 Fatigue Properties (Index) 100 88 92 99

* HD's: Hardness

* 300% Modulus: Stress at 300% elongation of vulcanized rubber (kg / cm ² )

* TS: Maximum stress (kg / cm ² ) when rubber is cut after vulcanized rubber is stretched at constant speed with tensile strength.

* E.B: The elongation of the vulcanized rubber after stretching at a constant speed as the elongation (%)

* Transmission coefficient: air permeability (cc / m ² atm.day) of vulcanized rubber of 1 mm thickness at 60 ° C

* Improvement index (Index): The degree of improvement of each item is expressed as a relative value based on Comparative Example 1 of the measured permeation coefficient of 100

* Fatigue characteristics (Index): Measured cracks after measuring 1 million cycles with DE MATTIA bending cracking tester. The degree of improvement of each item is shown as relative value based on Comparative Example 1 as 100

Referring to Table 1, when the spherical inorganic filler (CaCO ₃ ) is applied as in Comparative Examples 2 and 3, the air permeability improves as the particle size increases. However, the fatigue property is rapidly lowered. As shown in Example 1, the inner air permeability of the inner liner rubber is comparable to that of the inner liner rubber because the particle size of the inner liner rubber is smaller than that of the spherical shape by air tightness filler, and the air permeability is improved by 17% Or more.

Claims (4)

delete delete Step S1 in which inorganic filler and asphalt are stirred at 150 to 250 占 폚 to ensure homogeneity and to increase the initial viscosity to 90 to 110 MU at the start of the initial blending by 150% Which means a viscosity of 135 to 165 MU, which is a 150% increase from 90 to 110 MU at the start of the initial formulation);
When the initial viscosity is reached, the process oil and coal ash are added and the mixture is secondarily stirred to the final viscosity, further adding carbon black to bring the end viscosity to three times the viscosity at the start of the initial formulation; And
Pressing the mixture at a high pressure of at least 100 bar at an end viscosity to form a plate having a specific gravity characteristic of 1.3 to 1.7 g / m < ³ &
Wherein the step (S2) further comprises adding an aramid short fiber, wherein the aramid short fiber has a diameter of 0.1 to 2 mu m and a length of 5 to 50 mu m.
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