JP3283670B2 - tire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire having a pattern made of brightly colored rubber on a sidewall surface.

[0002]

2. Description of the Related Art Conventionally, as a tire whose side wall surface is decorated with a pattern made of bright rubber, there is a tire in which characters and lines made of bright rubber are provided on the sidewall surface. For example, a tire having a white line pattern as shown in FIG. 6 extrudes a sidewall rubber in a belt shape and coaxially extrudes a color rubber,
A rubber belt obtained by further laminating a black rubber layer 3 for coating on a belt surface in which the black rubber portion 1 and the brightly colored rubber portion 2 are combined is molded as a sidewall portion 5 into a green tire. After vulcanization, it is manufactured by buffing the black rubber layer 3 for coating along the tire peripheral surface using a grinder to expose a line 4 made of brightly colored rubber.

[0003] In addition, when characters made of bright colored rubber are applied, they are manufactured in the same manner. That is, letters were engraved at predetermined positions by embedding a clear rubber layer in a belt-like black rubber layer and using a rubber belt formed by laminating a black rubber layer for coating on the surface of the clear rubber layer as a sidewall. A green tire is molded in a mold and vulcanized. In the molded and vulcanized tire, the character portion protrudes from the sidewall surface, so buffing this protruding portion with a grinder to remove the black rubber layer for coating, the inside clear rubber layer becomes the shape of the character Exposed.

[0004]

However, since white lines and characters are monotonous in design, more complicated and various patterns have been demanded. On the other hand, according to the above manufacturing method, the design of the pattern is easy to be standardized,
Difficult to meet the varied demands of buyers, especially young people.

[0005] As a method of providing a desired design, Japanese Utility Model Application Laid-Open No. 58-56602 discloses a method in which a side wall surface of a tire molded and vulcanized by using a black rubber belt having embedded therein a clear rubber as a side wall as described above is used. A method has been proposed in which a desired design is carved by using an electric heating knife or the like for cutting out a groove in a tread portion, thereby exposing an inner clear rubber layer to form a pattern. However, when a pattern formed over the entire sidewall surface, for example, a woodgrain or marble pattern is applied,
Such a method is troublesome.

The present invention has been made based on such a technical background, and an object of the present invention is to provide a variety of and durable patterns capable of meeting the needs of consumers. In providing tires.

[0007]

The tire of the present invention has a black color.
When molding the rubber into a sheet,
With this, the side wall matri made of the black rubber
The bright colored rubber is mixed unevenly in the box 11a
Part on which the patterned part 11b is formed
10 is characterized. As the black rubber constituting the side wall matrix 11a, a diene rubber is 20 to 70 parts by weight in 100 parts by weight of a rubber component,
In addition, it is preferable to use a non-staining black rubber material containing 30 to 80 parts by weight of the total of at least one or both of the halogenated butyl rubber and the EPDM, and containing no staining antioxidant.

The bright colored rubber forming the pattern portion 11b is composed of 20 parts by weight of a diene rubber in 100 parts by weight of a rubber component.
〜60 parts by weight, preferably 20 parts by weight or more of halogenated butyl rubber and 20 parts by weight or more of EPDM.

[0009]

FIG. 1 shows an embodiment of a tire according to the present invention. In FIG. 1, reference numeral 10 denotes a sidewall portion which forms a sidewall portion of the tire and is provided on the carcass rubber portion 9. The side wall portion 10 includes a side wall matrix 11a made of black rubber, and a pattern portion 11b in which a brightly colored rubber is mixed in the side wall matrix 11a.

As the black rubber forming the side wall matrix 11a, it is necessary to use a rubber which is non-staining and is excellent in weather resistance and ozone resistance with respect to the bright colored rubber forming the pattern portion 11b. Specifically, diene rubber, ethylene-propylene-diene terpolymer (EP
DM) and a combination of a halogenated butyl rubber; a combination of a diene rubber and a halogenated butyl rubber; a rubber component of any one of a combination of a diene rubber and EPDM;
A black rubber material containing carbon black as a filler and no contaminating antioxidant is used (hereinafter, referred to as a “non-staining black rubber material”). More specifically, in 100 parts by weight of the rubber component, 20 to 70 parts by weight of the diene rubber and 30 parts by weight or more, preferably 50 to 80 parts by weight of the halogenated butyl rubber and EPDM alone or both are contained. As the diene rubber, natural rubber, butadiene rubber, isoprene rubber, styrene rubber and the like are used.

The term "stainable antioxidant" as used herein refers to an antioxidant having contamination, such as an amine antioxidant or a carbamate antioxidant, which migrates to the adjacent pattern portion 11b to form the antioxidant. Not blended because it contaminates bright colored rubber. If the weight ratio of the halogenated butyl rubber and EPDM is less than 30 parts by weight, the weather resistance and ozone resistance will be inferior. On the other hand, if the weight ratio of the halogenated butyl rubber and EPDM exceeds 80 parts by weight, the diene will be relatively reduced. Since the amount of the system rubber is reduced, the bending resistance is reduced and the durability as a tire is inferior.

The rubber material for the side wall matrix 11a will be described based on a specific example. Natural rubber (NR), butadiene rubber (BR), EPDM, and chlorinated butyl rubber (Cl-IIR) were blended in the amounts shown in Table 1 to give a rubber component of 100 parts by weight, and the additives shown in Table 2 were added thereto. The rubber composition Nos. Shown in Table 1 were blended in respective amounts. 1
~ 8. Among them, the rubber composition No. 3-6
Is a rubber composition (Example) according to the present invention. Rubber composition No. For 1 to 8, 300% modulus, tensile strength, flex resistance, ozone resistance (static and dynamic), and adhesion to the brightly colored rubber according to the present invention were examined. Table 1 also shows the results. In Table 1, the tensile strength is represented by the tensile strength when a vulcanized rubber test piece was prepared from the rubber composition, subjected to a tensile test, and broken. The flex resistance was measured by inserting a 2 mm crack into the prepared vulcanized rubber specimen and measuring the resistance to cracking when repeatedly bending (10,000 times). The evaluation was made in two stages of small (x). The ozone resistance (static) was evaluated by performing an ozone deterioration test on a vulcanized rubber test piece under the conditions of 40 ° C. and an ozone concentration of 50 pphm, and determining the degree of cracking according to JIS K6301.
It evaluated according to. That is, the number of cracks is A (small) to
C (innumerable), the size and depth of the cracks are evaluated by combining 1 (invisible to the naked eye but recognizable with a 10 × magnifying glass) to 5 (thresholding to cause a crack or cut of 3 mm or more) did. For ozone resistance (dynamic), a tire using the above rubber composition for a sidewall was prepared, and an ozone deterioration test was performed while running the tire under the same conditions as the static test. Evaluation was made based on the same criteria.

[0013]

[Table 1]

[0014]

[Table 2]

As can be seen from Table 1, the rubber composition No. 1 containing less than 30% by weight of EPDM and halogenated butyl rubber in total. 7 and 8 are inferior in ozone resistance. In addition, the rubber composition No. 1 containing less than 20 parts by weight of the diene rubber was used. 1 and 2 were inferior in bending resistance and adhesiveness. On the other hand, the rubber composition No. 3-6
Had satisfactory properties.

The bright rubber forming the pattern portion 11b is a rubber having good adhesion to the black rubber forming the sidewall matrix 11a and having excellent ozone resistance. Specifically, white fillers 40 to 8 are added to 100 to 100 parts by weight of a rubber component containing 20 to 60 parts by weight of diene rubber, 20 parts by weight or more of halogenated butyl rubber, and 20 parts by weight or more of EPDM.
A rubber material containing 0 parts by weight is preferably used.

As the halogenated butyl rubber, chlorinated butyl rubber, brominated butyl rubber, or a mixture thereof can be used. The reason why the weight ratio of the halogenated butyl rubber to 100 parts by weight of the rubber component is 20 parts by weight or more is that if less than 20 parts by weight, the bending resistance is poor. E
PDM usually has a monomer composition of 50 to 8 ethylene.
0% by weight and 20 to 50% by weight of propylene. Examples of the diene include rubbers using ethylidene norbornene, dicyclopentadiene, and 1,4 hexadiene. The weight ratio of EPDM to 100 parts by weight of the rubber component is 2
The reason why the amount is set to 0 parts by weight or more is that if it is less than 20 parts by weight, the ozone resistance is poor.

As the diene rubber, natural rubber, polyisoprene rubber, polybutadiene rubber or a mixture thereof is used. The weight ratio of the diene rubber is preferably 20 to 60 parts by weight based on 100 parts by weight of the rubber component. If the amount is less than 20 parts by weight, the adhesion of the side wall matrix 11a to the black rubber is inferior, and if it exceeds 60 parts by weight, the ozone resistance is inferior.

As the white filler, clays, calcium carbonate, white carbon, alumina, titanium oxide and the like are used. Further, an additive such as a coloring agent may be appropriately added as needed. The light-colored rubber for the pattern portion 11b will be described based on a specific example. NR, EPDM,
Each chlorinated butyl rubber (Cl-IIR) was blended in the amounts shown in Table 3 to give a rubber component of 100 parts by weight.
o. 9-18 were obtained. Among these rubber compositions, N
o. 13 to 16 are rubber compositions (examples) according to the present invention. These rubber compositions were examined for ozone resistance (static and dynamic) and adhesiveness with the brightly colored rubber according to the present invention. Table 3 also shows the results.

[0020]

[Table 3]

[0021]

[Table 4]

As can be seen from Table 3, the rubber composition No. 1 containing less than 20 parts by weight of natural rubber. 17 and 18 (Comparative Examples) were inferior in adhesion to black rubber. The rubber composition No. 1 containing less than 20 parts by weight of the halogenated butyl rubber. Rubber compositions Nos. 9 to 11 were inferior in flex resistance and contained less than 20 parts by weight of EPDM. 9, 10, and 12 were inferior in ozone resistance. On the other hand, the rubber composition No. 13
Nos. To 16 could satisfy all the characteristics.

Since the pattern portion 11b is formed by mixing bright colored rubber with the black rubber constituting the sidewall matrix 11a, the shape, size, etc. of the pattern portion 11b are determined by the method of mixing the bright colored rubber and the matrix. It depends on the occupancy ratio. Specifically, it can be formed by the following method. As shown in FIG. 2, the sidewall matrix 11 uniformly kneaded by a mixer such as a Banbury mixer.
The black rubber 23 for a is formed into a belt-like sheet between the calender rolls 25, 25, and the strip-shaped clear rubber 2
4 is formed into a sheet between the calender rolls 25, 25. When passing between the calender rolls 25, 25, a rubber belt 30 is formed in a state in which the bright rubber 24 is mixed non-uniformly in the belt-shaped black rubber 23 forming the sidewall matrix 11a. In such a rubber belt 30, the colored rubber 24 mixed unevenly in the sidewall matrix 11a made of the black rubber 23 becomes the pattern portion 11b. Therefore, each pattern part 11b has a complicated shape, and each has a different shape. Further, by adjusting the extruded amount of the bright colored rubber, the mixed state is different, and the black rubber and the bright colored rubber are mixed intricately, so that a marble or woodgrain pattern can be formed.

In addition to the method using a calender roll, a method using an extruder can similarly form a marble or woodgrain pattern. When an extruder is used, black rubber and light-colored rubber are put into the hopper at an appropriate ratio, and while passing through a screw, etc., the light-colored rubber is mixed unevenly in the black rubber, and The rubber belt on which the rubber pattern is formed is extruded.

The various pattern portions 11 thus obtained
The tire of the present invention can be obtained by molding and vulcanizing the tire by using the rubber belt 30 on which the b is formed for the sidewall portion. The obtained tire has high fashionability, unlike a monotonous pattern such as characters and lines in appearance. In addition, an innumerable variety of patterns can be formed depending on the arrangement of the pattern portions 11b, the amount of extrusion, and the like. Moreover, since the non-staining black rubber material is used around the pattern portion 11b, that is, for the side wall matrix 11a, it is possible to prevent the bright colored rubber of the pattern portion 11b from being discolored. Moreover, since the pattern portion 11b has a certain thickness, it is more resistant to wear and durable than a pattern formed using a film or the like. Further, according to the above-described manufacturing method, a buffing step or an engraving step for exposing the brightly colored rubber is not required, and the manufacturing for forming the pattern portion is facilitated.

It should be noted that not only one kind of brightly colored rubber but also
More than one kind may be used. By extruding different colored rubbers at an appropriate ratio or putting them into a hopper, more complicated and diverse patterns as shown in FIG. 3 can be formed. In FIG. 3, the pattern portion 11b1 and the pattern portion 11b2 are made of different colored rubbers. 2 bright colored rubber
By using more than one type, the variety of designs can be further expanded, and it is possible to easily meet the needs of various consumers.

Further, in the tire of the embodiment shown in FIGS. 1 and 3, the sidewall portion 10 is constituted only by the matrix 11a and the pattern portion 11b, but the present invention is not limited to this. That is, any configuration may be used as long as the pattern portion 11b appears on the surface portion of the sidewall portion 10. For example,
As shown in FIG. 4, the side wall matrix 11a
A sidewall base portion 12 made of black rubber may be provided on the inner surface side of the tire. In this case, the black rubber forming the sidewall base portion 12 includes a rubber component 1
A non-staining black rubber containing 20 to 60 parts by weight of a diene rubber and 40 parts by weight or more of a halogenated butyl rubber in 00 parts by weight and containing no contaminating anti-aging agent such as an amine-based anti-aging agent. Use materials. By using a non-staining material for the sidewall base portion 12, the pattern portion 11b is not contaminated.

Further, a sidewall base inner rubber portion 13 is provided on the tire inner surface side of the sidewall portion 12,
The sidewall portion 10 may be configured. In this case, the black rubber material used for the sidewall base inner rubber portion 13 is not particularly limited as long as it is a rubber composition containing a diene rubber as a main component. For example, the rubber composition Nos. As in the case of 17, 18, any rubber composition can be used irrespective of the presence or absence of a contaminating antioxidant. In the case where a rubber in which an amine-based anti-aging agent is blended is used for the sidewall base inner rubber portion 13,
The thickness t of the sidewall base portion 12 is set so as not to contaminate the pattern portion 11b through the sidewall base portion 12.
Is preferably 2 mm or more.

[0029]

[Table 5]

As shown in the embodiment shown in FIGS. 4 and 5, the thickness of the sidewall matrix 11a is reduced by providing the sidewall base 12 and the sidewall base inner rubber 13 on the tire inner surface side of the sidewall matrix 11a. By making it thinner, the amount of brightly colored rubber used can be reduced, and the price increase of the patterned tire can be suppressed.

[0031]

The tire of the present invention has a black rubber sheet shape.
Black by adding bright rubber when molding into
Clear colored rubber in the rubber sidewall matrix
Pattern is formed by uneven mixing
Be one having a side wall portion, because of the use of rubber component having a specific chemical composition as a light迷色rubber constituting the side black rubber and the pattern portions constituting the wall matrix, for example, wood or marble Modest
A variety of patterns can be easily configured
You . Also, the pattern portion formed in this manner, Kokushokugo
Rubber itself added when forming the rubber sheet into a sheet
, And is more resistant to wear and durable than a pattern formed by printing or the like. Further, since the non-staining black rubber material is used for the black rubber forming the sidewall matrix, the bright rubber portion forming the pattern portion is hardly discolored, and a beautiful pattern can be maintained.

[Brief description of the drawings]

FIG. 1 is a sectional perspective view of a tire according to an embodiment of the present invention .

FIG. 2 is a diagram for explaining an example of a tire manufacturing method according to an embodiment of the present invention .

FIG. 3 is an enlarged sectional view of a tire according to another embodiment of the present invention .

FIG. 4 shows a tire according to another embodiment of the present invention in an arbitrary cross section.
It is a perspective view at the time of cutting .

FIG. 5 is a sectional perspective view of a tire according to an embodiment of the present invention .

FIG. 6 is a sectional perspective view showing a conventional tire.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Side wall part 11a Side wall matrix 11b Pattern part 12 Side wall base part 13 Side wall base inner rubber 23 Belt-like black rubber 24 Bright rubber 30 Rubber belt

Claims (2)

(57) [Claims] (1) When molding black rubber into a sheet,
By adding a colored rubber, the black rubber
In the id wall matrix (11a),
Pattern (11b) is formed by non-uniform mixing
In a tire having a sidewall portion (10) being
The black rubber constituting the sidewall matrix (11a) is composed of 20 to 70 parts by weight of a diene rubber, 100 parts by weight of a rubber component, and halogenated butyl rubber and E in 100 parts by weight of a rubber component.
A non-staining black rubber material containing 30 to 80 parts by weight of a total of at least one or both of the PDMs and containing no staining anti-aging agent, and constituting the pattern portion (11b). The bright colored rubber has a rubber component of 100
A tire containing 20 to 60 parts by weight of a diene rubber, 20 parts by weight or more of a halogenated butyl rubber, and 20 parts by weight or more of EPDM in parts by weight. 2. The sidewall portion (10) has a sidewall base portion (12) on the tire inner surface side of a sidewall matrix (11a), and the sidewall base portion (12) is made of a rubber component. 100 parts by weight, a non-staining black rubber material containing 20 to 60 parts by weight of a diene rubber and 40 parts by weight or more of a halogenated butyl rubber and containing no stain-resistant antioxidant. The tire according to claim 1, wherein: