KR101103093B1 - Tire comprising Rubber Composition for a wear indicator - Google Patents

Abstract

The present invention relates to a tire including a wear composition rubber composition layer, and more particularly, a tire that can easily be grasped with the naked eye only by the thickness of the wear composition rubber composition layer exposed on the surface of the tread block when the tire wears. A wear indicator rubber composition layer having a different color from the tread block is placed in the tread block, and the wear indicator rubber composition may be added with dyes and pigments to give a different color from the tread rubber while maintaining physical properties of the tread rubber composition. It relates to a tire comprising a wear composition rubber composition layer.

Tread wear, rubber composition layer, tire

Description

Tire comprising rubber composition layer for wear indication {Tire comprising Rubber Composition for a wear indicator}

The present invention relates to a tire including a wear indicator rubber composition layer, and more particularly to a tire that can easily observe the degree of wear of the tire while maintaining the physical properties of the tread portion rubber.

Among the parts of the tire for the car, the tread part directly touches the ground, which is very important for the driver's safety. As the tire is used, the tread portion rubber gradually wears out, and as the tread portion rubber wears down, braking and cornering performance deteriorates. Therefore, various techniques have been proposed to check the wear state of the tread rubber.

A commonly used method is to have a wear indicator appear on the tread surface so that the tread is over worn. However, since these wear indicators are the same rubber as the tread part, they are not easily seen unless carefully examined, and there is an inconvenience in that the part having the indicators must be found on the circumference of the tire to check the wear state.

Therefore, a method of placing a wear indicator in the groove of the tire tread part on the deco portion above the sidewall part has also been proposed. In this method, because the wear indicator is black, the wear state cannot be easily checked without careful attention. There was this.

In addition, a technique for arranging different colored rubbers according to the height of the tread portion to make it easy to recognize the state of wear or ideal wear is proposed. However, in order to make different colors appear, several rubbers have to be used. In this case, the extruder equipment is required as many kinds of rubbers as tires are manufactured. There was a problem to be sacrificed.

Therefore, there is still a need for a tire that can visually check the degree of tire wear while maintaining the properties of the tread portion rubber.

The present invention is to meet the above technical requirements, one problem to be solved by the present invention is to provide a wear-resistant rubber composition layer to easily grasp the wear of the tire with the naked eye while maintaining the physical properties of the tread rubber composition It is to provide a tire containing.

One aspect of the present invention for achieving the above object comprises a wear indicator rubber composition layer different in color from the tread rubber inside the tread block of the tire, the wear indicator rubber composition layer is at least along the circumferential direction of the tire Located in one or more of the tread block, the wear indicator rubber composition layer relates to a tire having a triangular shape in which the cross section in the width direction of the tire narrows in the direction of the surface of the tread block from the inside of the tire.

The wear indicator rubber composition layer may display the wear degree of the tire, including 5 to 40 parts by weight of the dye and pigment based on 100 parts by weight of the raw rubber, the physical properties of the wear indicator rubber composition layer of the tire tread Similar to the physical properties of the block it is possible to provide a wear indicator tire without deteriorating the physical properties.

According to embodiments of the present invention, by including a wear-indicating rubber composition layer having a certain shape inside the tread of the tire and including dyes and pigments, the tread according to the degree of wear of the tire without affecting the physical properties of the tire tread portion Specific colored bands appear on the surface of the block, so that the wearer can easily grasp the degree of wear with the naked eye, thereby providing a tire for the driver's safety.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. The accompanying drawings show a schematic shape for easy understanding of the invention, and the invention is not limited to the width or thickness thereof.

The present invention relates to a tire including a wear indicator rubber composition layer having physical properties similar to those of a tread, which is an important part of the tire in contact with the ground, while being able to easily grasp the wear level of the tire.

1 is a cross-sectional view of the tread portion of a tire according to an embodiment of the present invention, the cross-sectional view is a cross-sectional view in the width direction of the tire.

Referring to FIG. 1, a tire according to an embodiment of the present invention includes a wear composition rubber composition layer 2 having a different color from a tread rubber in the tread block 1 of the tire, wherein the wear composition rubber composition is included. The layer 2 is located inside at least one of the tread blocks 1 along the circumferential direction of the tire, and the wear-resistant rubber composition layer 2 has a cross section in the width direction of the tire in the tread block. It has a triangular shape that narrows in the direction of the surface of.

2A, 2B and 2C are cross-sectional views of the tread portion and the tread block surface according to the wear level of the tire according to an embodiment of the present invention, the front view of the tread block surface is a front view of the tire surface viewed from the outside of the tire A partial cross-sectional view of the tread part corresponds to a cross-sectional view taken along the AA ′ direction, that is, the width direction of the tire, to more easily understand the change of the tire according to the degree of wear.

Figure 2a shows the state before the use of the tire, the tread block 10 has a wear indicator rubber composition layer 20 having a different color from the tread block, but such a wear indicator rubber composition layer is located outside the tire. Invisible This is because the wear-indicating rubber composition layer has a triangular cross-sectional shape that narrows toward the tread block surface of the tire.

FIG. 2B illustrates a state in which tire wear occurs according to the use of the tire, and as the tire wears, the wear composition rubber composition layer 21 positioned inside the tread block 11 appears on the outer surface of the tire. do.

Finally, Figure 2c shows the tire at the time of replacement according to the wear of the tire, the tread according to the wear of the tire by having a triangular cross-sectional shape narrowing toward the surface of the tread block of the wear rubber composition composition The wear indicator rubber composition layer 22 located inside the block 12 appears on the tire outer surface with a wider width than that shown in FIG. 2B.

For example, when the wear-resistant rubber composition layer is exposed to the outside of the tire based on the tread block width 1/3 or more of the surface may mean that the replacement time of the tire. That is, in this case, the wear limit line of the tire is 1/3 of the exposed portion of the wear composition rubber composition layer with respect to the width of the tread block of the tire, but is not necessarily limited thereto. It can be varied by adjusting the height of the or the width of the base.

The tire according to the embodiments of the present invention may be located in the at least one tread block in the wear-resistant rubber composition layer in the circumferential direction of the tire, that is, the tire traveling direction. That is, the tread portion of the tire may be included in the tread block between at least one neighboring circumferential main groove, and thus the abnormal wear state may also be visually observed due to the deviation of the exposure of the wear composition rubber composition layer in the circumferential direction. It is easy to see.

The wear indication rubber composition layer has a cross section in the width direction of the tire at the inner side of the tire, that is, at the inner liner portion of the tire. It has a triangular shape that narrows outwardly of the tire, i.e., toward the surface of the tread block, and the underside of the triangular cross section, i.e., the beginning of the wear-indicating rubber composition layer may be an under tread, but wear to the under tread of the tire is reduced. What happens is not desirable, depending on the practicality it is better to be similar to the beginning of the tread block. In addition, such a structure is made possible because the rubber composition for wear display according to the embodiments of the present invention has the same or similar physical properties as the rubber composition of the tread portion, unlike the prior art.

Therefore, the wear indication rubber composition layer comprises 5 to 40 parts by weight of dyes and pigments based on 100 parts by weight of the raw material rubber in order to exhibit a different color from the tread part rubber, the dyes and pigments within the range is a tread part rubber composition In order to express the physical properties of the dyes and pigments similar to the well and to avoid the use of carbon black in the reinforcing agent, by using silica to enable the difference in color with the tire tread portion.

The dyes and pigments usable in the present invention have a color which can be differentiated from the general index black of the tread portion of a tire, and as long as it is heat stable, those generally used in the art can be used, and are not particularly limited. The ratio of the dye and the pigment is preferably 1: 0.5 to 1: 1.5, but is not limited thereto. It is preferable to use a dye and a pigment having the same color together rather than using the dye or the pigment alone.

These dyes and pigments are merely for imparting color and do not affect the physical properties of the rubber composition of the tread portion of the tire.

Specifically, examples of the dye that can be used in one embodiment of the present invention include blue blue (Ultramarine Blue), red RED 120 of China Changsha Zhonglong Chemical RED, etc., but is not limited thereto. It is not.

In addition, examples of the pigment that can be used in one embodiment of the present invention include Sudan Blue of BASF, which has a blue color, and Remazol Red RR of Dysta, which has a red color, but are not limited thereto. It is not.

By using dyes and pigments of this color, the color of the wear indicator rubber composition layer may represent the color of dyes and pigments such as blue or red.

The wear indicator rubber composition layer included in the tire is specifically as follows.

The wear indicator rubber composition layer is 100 parts by weight of at least one synthetic rubber and 50 to 100 parts by weight of silica, 5 to 15 parts by weight of softener, 3 to 5 parts by weight of vulcanizing agent, dye and pigment based on 100 parts by weight of the synthetic rubber. 5 to 40 parts by weight, 1 to 5 parts by weight of vulcanizing agent and 1 to 5 parts by weight of vulcanization accelerator.

The raw material rubber usable in the present invention is preferably at least one synthetic rubber, and is not particularly limited to one which can be used in a conventional rubber composition for tires. Examples of the synthetic rubber include styrene butadiene rubber (SBR), butadiene rubber (BR), nitrile butadiene rubber (NBR), or chloroprene rubber (CR) as a diene polymer. ), Isoprene-isobutylene rubber (IIR), and the like. For example, 20 to 100 parts by weight of styrene butadiene rubber and 20 to 100 parts by weight of butadiene rubber may be used together, and the ratio between the synthetic rubbers may be appropriately adjusted.

The wear composition rubber composition layer of the present invention includes a filler to improve the physical properties of the vulcanized rubber and the processability of the unvulcanized rubber. As such a reinforcing agent, silica may be used.

Particularly, in the embodiments of the present invention, silica is mainly used without the use of carbon black as a reinforcing agent to impart different colors while exhibiting the same physical properties as the conventional tread part rubber composition layer. The silica may be included in an amount of 50 to 100 parts by weight based on 100 parts by weight of the raw rubber. If the content is less than 50 parts by weight, reinforcement may not be expected. Can be too large.

In addition to the reinforcing agent, the following fillers for workability may be additionally used in the wear indicator rubber composition layer of the present invention. Examples of the filler include titanium dioxide, clay, tungsten, talc, syndiotactic-1,2-polybutadiene (SPB), and the like. Can be used, but is not necessarily limited to these.

A softening agent may be used in the wear marking rubber composition layer of the present invention to soften the rubber to facilitate processing. Examples of the softener that can be used in the present invention include plant-based softeners such as castor oil, pine tar, and tall oil, and mineral-based softeners such as process oil. Hydrocarbons are classified into paraffins, naphthenes, and aromatics, but are not necessarily limited thereto. The softener may be included in an amount of 5 to 15 parts by weight based on 100 parts by weight of the raw rubber, and when the softener is less than 5 parts by weight, the plasticizer does not appear.

The wear composition rubber composition layer of the present invention may include a vulcanizing agent for giving a strong active effect to the crosslinking reaction of synthetic rubber, in particular, a diene-based rubber, and the vulcanizing agent reacts with sulfur, a vulcanization accelerator, and a vulcanizing agent by vulcanization. It forms a bridge to form a rubber. Examples of the vulcanizing agent include zinc oxide and stearic acid, but are not limited thereto. The vulcanizing active agent may be included in an amount of 3 to 5 parts by weight based on 100 parts by weight of the raw rubber. If the vulcanizing agent is out of the range, the vulcanization time may be lengthened or the physical properties of the vulcanized rubber may be reduced.

The wear composition rubber composition layer of the present invention may use a conventional vulcanizing agent (or vulcanizing agent) for the crosslinking of rubber, and the vulcanizing agent may include sulfur, organic peroxide, magnesium oxide, etc., but most sulfur is used. Through vulcanization, the compounded rubber containing various additives in the raw material rubber becomes vulcanized rubber.

In addition, the vulcanizing agent may be used in combination with a vulcanization accelerator (or vulcanization accelerator). Examples of the vulcanization accelerator that can be used in the present invention include ammonia, amine, guanidine, thiazole, thiuram, sulfamide, and the like, specifically diphenylguanidine (DPG). , N- (cyclohexyl benzothiazolyl-2- sulfenamide (CBS), but is not limited thereto. The vulcanizing agent is based on 100 parts by weight of the raw rubber It may be included in 1 to 5 parts by weight, when out of the range scorch stability is lowered rubber elasticity or elongation, modulus, etc. is too small or large, the vulcanization accelerator 1 to 5 with respect to 100 parts by weight of the raw rubber It may be included in parts by weight, if out of the above range crosslink density is small or large to obtain the desired physical properties.

The wear indicator rubber composition layer of the present invention may further include an additive that is typically used in the rubber composition for tires. For example, examples of such other additives include silane coupling agents, antioxidants, plasticizers, antioxidants, ozonation inhibitors, extended oils, and the like.

Silane coupling agents usable in embodiments of the invention include bis- (3- (triethoxysilyl) -propyl) -disulfide (bis- (3- (triethoxysilyl) -propyl) -disulfide (TESPD) or bis- (3- (triethoxysilyl) -propyl) -tetrasulfide (bis- (3- (triethoxysilyl) -propyl) -tetrasulfide (TESPT)), but is not necessarily limited to these. These are each marketed under the trade names Si75 and Si69 by Degussa, Germany. The content of the silane coupling agent may be 20 to 170 parts by weight based on 100 parts by weight of the raw rubber.

Rubber products are gradually aging their properties during use, and anti-aging agents may be used to prevent or relax the progress of this aging and to prolong the service life. Such anti-aging agents require conditions such as high solubility in rubber in addition to anti-aging action and not inhibiting vulcanization, and phenols or aromatic amines are generally used. Examples of anti-aging agents usable in the present invention include 2,2'-methylenebis (4-methyl-6-t-butylphenol) (2,2'-Methylenebis (4-methyl-6-tert-butylphenol): MBMTB) , N- (1,3-dimethylbutyl) -N-phenyl-p-phenylenediamine (N- (1,3-Dimethyl butyl) -N-phenyl-p-phenylenediamine), N-phenyl-N'isopropyl N-phenyl-N'-isopropyl-p-phenylenediamine (IPPD) and polymerized 2,2,4-trimethyl-1,2-dihydroquinoline (polymerized 2,2,4-trimethyl -1,2-dihydroquinoline: TMDQ) and the like, but is not necessarily limited thereto.

In addition, the wear indicator rubber composition layer of the present invention may include processing aids such as lubricants such as waxes that improve fluidity during processing, active agents such as amines that can make sharp vulcanized rubbers, or dispersants that improve the dispersion of compounded rubbers. have.

The wear indicator rubber composition layer according to embodiments of the present invention may be prepared according to techniques known to those skilled in the art. For example, the rubber composition of the present invention is obtained by kneading using a kneader such as an open kneader such as an open mill, a roll, or a sealed kneader such as a Banbury Mixer, and after molding processing The vulcanizing agent and the vulcanizing accelerator are added to vulcanize at a constant temperature, whereby various rubber products can be produced.

Hereinafter, the present invention will be described in more detail with reference to the following examples in order to help understand the present invention, but various modifications may be made to the embodiments according to the present invention, and the scope of the present invention is limited to the following examples. It should not be interpreted.

Examples 1-4

In accordance with the composition shown in Table 1, based on 100 parts by weight of the raw material rubber and 100 parts by weight of the raw material rubber, silica, TESPT as a silane coupling agent, oil as a softener, zinc oxide as a vulcanizing agent and stearic acid together with rubber 10 parts by weight of dyes and pigments were added and mixed so as to show the color, and then mixed in a Banbury Mixer and released at 150 ° C. to prepare an unvulcanized rubber composition. A rubber specimen was prepared by additionally adding an accelerator and an anti-aging agent and quenching at 160 ° C. for about 9 minutes to 10 minutes.

Comparative example  1 to 2

As shown in Table 1, rubber samples for tread parts were prepared in the same manner as in Examples 1 to 2, except that dyes and pigments were not added in the rubber compositions of Examples 1 to 2.

* Silica: Ultra 7000Gr (Degussa)

* TESPT: Bis (3-triethoxysilylpropyl) tetrasulfide (Degus Co., Ltd.)

* Softener: Oil

* Antioxidant: N-1,3-dimethylbutyl-N-phenyl-p-phenylenediamine (trade name: Nocrac 6C (大 內))

* A1: Sudan Blue (BASF)

* A2: Remazol Red RR (Dysta)

* B1: Ultramarine Blue (Dongguan High Grade Chemical)

* B2: RED 120 (China Changsha Zhonglong Chemical)

DPG: diphenylguanidine

* CBS: N- (cyclohexyl benzothiazolyl-2-sulfenamide)

For reference, the physical properties of the dyes and pigments used in Examples 1 to 4 are as shown in Tables 2 and 3, respectively.

<Property evaluation method>

The physical properties of the unvulcanized rubber composition and rubber specimens prepared in Examples 1 to 4 and Comparative Examples 1 and 2 were measured by ASTM-related regulations as follows, and the results are shown in Table 4 below.

Experimental Example  One - Unvulcanized  Rubber Scorch  stability

Scotch time was measured by a monetary viscosity. It is measured as the time from the lowest viscosity to 5 points of increase in the pattern unit. The longer the time, the more stable the scorch.

Experimental Example  2-Evaluation of tensile properties of rubber

(1) hardness measurement

Hardness is measured by using a spring type A hardness tester according to ASTM D2240, which measures the movement of the spring by sticking a pressure needle attached to the end of the spring with a constant elasticity to rubber.

(2) 300% modulus

Modulus refers to the force that can be maintained when the rubber specimen is stretched, and the modulus measurement is measured by using a universal testing machine (Instron) by cutting the manufactured rubber specimen into a dumbbell shape, 300% modulus When 300% elongation refers to the stress acting on the specimen.

(3) Elongation and tensile strength measurement

Elongation is the length obtained by dividing the length by the initial length until it breaks while holding one end of the dumbbell-shaped rubber specimen and pulling on the other. In addition, the tensile strength was compared by measuring the force applied when breaking.

As can be seen in Table 4, when compared to the physical properties of the rubber specimens used in the general tread portion of the wear indicator rubber specimens prepared in Examples 1 to 4, hardness, 300% modulus, It can be seen that there is no significant change in all tensile properties of elongation and tensile strength, and the evaluation of the workability of unvulcanized rubber, which is a rubber before vulcanization, has almost the same vulcanization time. There is no fear of deterioration of physical properties, and there is almost no difference in scorch time, and thus it can be confirmed that there is no difference in physical properties even in workability of unvulcanized rubber. That is, it can be confirmed that the physical properties of the rubber composition of the tire can be maintained even if the pigment and dye are included.

Although the present invention has been described in detail with reference to preferred embodiments of the present invention, these are merely exemplary, and those skilled in the art to which the present invention pertains have various modifications and equivalents therefrom. It will be appreciated that embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a cross-sectional view of the tread portion of a tire according to an embodiment of the present invention.

2A, 2B and 2C are cross-sectional views of the tread portion and the front surface of the tread block according to the degree of wear of the tire according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

1, 10, 11, 12: tread portion 2, 20, 21, 22: wear-resistant rubber composition layer

Claims (8)

A wear indicator rubber composition layer having a different color from the tread rubber is included in the tread block of the tire, and the wear indicator rubber composition layer is positioned in at least one of the tread blocks along the circumferential direction of the tire, and the wear indicator The rubber composition layer has a triangular shape in which the cross section in the width direction of the tire narrows from the inside of the tire toward the surface of the tread block. The wear indicator rubber composition layer is 100 parts by weight of at least one synthetic rubber and 50 to 100 parts by weight of silica, 5 to 15 parts by weight of softener, 3 to 5 parts by weight of vulcanizing agent, dye and pigment based on 100 parts by weight of the synthetic rubber. A tire comprising 5 to 40 parts by weight, 1 to 5 parts by weight of vulcanizing agent and 1 to 5 parts by weight of vulcanization accelerator. delete The tire as claimed in claim 1, wherein physical properties of the wear indicator rubber composition layer are similar to those of the tread block of the tire. The tire as claimed in claim 1, wherein a color of the wear indicator rubber composition layer is blue or red. According to claim 1, wherein the tire is a tire, characterized in that the tire replacement time when the wear-resistant rubber composition layer on the surface of the tread block of the tire is exposed more than 1/3 of the width of the tread block . delete A tire according to claim 1, wherein the ratio of dye and pigment is 1: 0.5 to 1: 1.5. The tire according to claim 1, wherein the wear indicator rubber composition layer further comprises a silane coupling agent or an anti-aging agent.

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